Title 10
PART 430 APPENDIX M1
When
determined for a ducted coil-only system, EER must include, from
this appendix, the section 3.3 and 3.5.1 default values for the
heat output and power input of a fan motor. The represented value
of EER determined in accordance with appendix M1 is EER2.
2.1 Test Room
Requirements.
where: Vi (i=2,3,4
. . .) = the internal volume of the pressure measurement system
(pressure lines, fittings, and gauge and/or transducer) at the
location i (as indicated in Table 2), (cubic inches) fi (i=5,6) = 0
if the pressure measurement system is pitched upwards from the
pressure tap location to the gauge or transducer, 1 if it is not. r
= the density associated with liquid refrigerant at 100 °F bubble
point conditions (ounces per cubic inch)
| Location | |
|---|---|
| Compressor Discharge | 1 |
| Between Outdoor Coil and Outdoor Expansion Valve(s) | 2 |
| Liquid Service Valve | 3 |
| Indoor Coil Inlet | 4 |
| Indoor Coil Outlet | 5 |
| Common Suction Port (i.e., vapor service valve) | 6 |
| Compressor Suction | 7 |
Calculate the internal volume of each pressure measurement system using internal volume reported for pressure transducers and gauges in product literature, if available. If such information is not available, use the value of 0.1 cubic inch internal volume for each pressure transducer, and 0.2 cubic inches for each pressure gauge.
In addition, for heat pumps that have a single expansion device located in the outdoor unit to serve each indoor unit, the internal volume of the pressure system at location 2 (as indicated in Table 2) must be no more than 1 cubic inches. Once the pressure measurement lines are set up, no change should be made until all tests are finished.
2.2.1 Defrost Control SettingsSet heat pump defrost controls at the normal settings which most typify those encountered in generalized climatic region IV. (Refer to Figure 1 and Table 20 of section 4.2 of this appendix for information on region IV.) For heat pumps that use a time-adaptive defrost control system (see section 1.2 of this appendix, Definitions), the manufacturer must specify in the certification report the frosting interval to be used during frost accumulation tests and provide the procedure for manually initiating the defrost at the specified time.
2.2.2 Special Requirements for Units Having a Multiple-Speed Outdoor FanConfigure the multiple-speed outdoor fan according to the installation manual included with the unit by the manufacturer, and thereafter, leave it unchanged for all tests. The controls of the unit must regulate the operation of the outdoor fan during all lab tests except dry coil cooling mode tests. For dry coil cooling mode tests, the outdoor fan must operate at the same speed used during the required wet coil test conducted at the same outdoor test conditions.
2.2.3 Special Requirements for Multi-Split Air Conditioners and Heat Pumps and Ducted Systems Using a Single Indoor Section Containing Multiple Indoor Blowers That Would Normally Operate Using Two or More Indoor ThermostatsBecause these systems will have more than one indoor blower and possibly multiple outdoor fans and compressor systems, references in this test procedure to a singular indoor blower, outdoor fan, and/or compressor means all indoor blowers, all outdoor fans, and all compressor systems that are energized during the test.
a. Additional requirements for multi-split air conditioners and heat pumps. For any test where the system is operated at part load (i.e., one or more compressors “off”, operating at the intermediate or minimum compressor speed, or at low compressor capacity), the manufacturer must designate in the certification report the indoor coil(s) that are not providing heating or cooling during the test. For variable-speed systems, the manufacturer must designate in the certification report at least one indoor unit that is not providing heating or cooling for all tests conducted at minimum compressor speed. For all other part-load tests, the manufacturer must choose to turn off zero, one, two, or more indoor units. The chosen configuration must remain unchanged for all tests conducted at the same compressor speed/capacity. For any indoor coil that is not providing heating or cooling during a test, cease forced airflow through this indoor coil and block its outlet duct.
b. Additional requirements for ducted split systems with a single indoor unit containing multiple indoor blowers (or for single-package units with an indoor section containing multiple indoor blowers) where the indoor blowers are designed to cycle on and off independently of one another and are not controlled such that all indoor blowers are modulated to always operate at the same air volume rate or speed. For any test where the system is operated at its lowest capacity - i.e., the lowest total air volume rate allowed when operating the single-speed compressor or when operating at low compressor capacity - turn off indoor blowers accounting for at least one-third of the full-load air volume rate unless prevented by the controls of the unit. In such cases, turn off as many indoor blowers as permitted by the unit's controls. Where more than one option exists for meeting this “off” requirement, the manufacturer must indicate in its certification report which indoor blower(s) are turned off. The chosen configuration shall remain unchanged for all tests conducted at the same lowest capacity configuration. For any indoor coil turned off during a test, cease forced airflow through any outlet duct connected to a switched-off indoor blower.
c. For test setups where the laboratory's physical limitations require use of more than the required line length of 25 feet as listed in section 2.2.a.(4) of this appendix, then the actual refrigerant line length used by the laboratory may exceed the required length and the refrigerant line length correction factors in Table 4 of AHRI 1230-2010 are applied to the cooling capacity measured for each cooling mode test.
2.2.4 Wet-Bulb Temperature Requirements for the Air Entering the Indoor and Outdoor Coils 2.2.4.1 Cooling Mode TestsFor wet-coil cooling mode tests, regulate the water vapor content of the air entering the indoor unit so that the wet-bulb temperature is as listed in Tables 5 to 8. As noted in these same tables, achieve a wet-bulb temperature during dry-coil cooling mode tests that results in no condensate forming on the indoor coil. Controlling the water vapor content of the air entering the outdoor side of the unit is not required for cooling mode tests except when testing:
(1) Units that reject condensate to the outdoor coil during wet coil tests. Tables 5-8 list the applicable wet-bulb temperatures.
(2) Single-package units where all or part of the indoor section is located in the outdoor test room. The average dew point temperature of the air entering the outdoor coil during wet coil tests must be within ±3.0 °F of the average dew point temperature of the air entering the indoor coil over the 30-minute data collection interval described in section 3.3 of this appendix. For dry coil tests on such units, it may be necessary to limit the moisture content of the air entering the outdoor coil of the unit to meet the requirements of section 3.4 of this appendix.
2.2.4.2 Heating Mode TestsFor heating mode tests, regulate the water vapor content of the air entering the outdoor unit to the applicable wet-bulb temperature listed in Tables 12 to 15. The wet-bulb temperature entering the indoor side of the heat pump must not exceed 60 °F. Additionally, if the Outdoor Air Enthalpy test method (section 2.10.1 of this appendix) is used while testing a single-package heat pump where all or part of the outdoor section is located in the indoor test room, adjust the wet-bulb temperature for the air entering the indoor side to yield an indoor-side dew point temperature that is as close as reasonably possible to the dew point temperature of the outdoor-side entering air.
2.2.5 Additional Refrigerant Charging Requirements 2.2.5.1 Instructions to Use for Charginga. Where the manufacturer's installation instructions contain two sets of refrigerant charging criteria, one for field installations and one for lab testing, use the field installation criteria.
b. For systems consisting of an outdoor unit manufacturer's outdoor section and indoor section with differing charging procedures, adjust the refrigerant charge per the outdoor installation instructions.
c. For systems consisting of an outdoor unit manufacturer's outdoor unit and an independent coil manufacturer's indoor unit with differing charging procedures, adjust the refrigerant charge per the indoor unit's installation instructions. If instructions are provided only with the outdoor unit or are provided only with an independent coil manufacturer's indoor unit, then use the provided instructions.
2.2.5.2 Test(s) to Use for Charginga. Use the tests or operating conditions specified in the manufacturer's installation instructions for charging. The manufacturer's installation instructions may specify use of tests other than the A or A2 test for charging, but, unless the unit is a heating-only heat pump, determine the air volume rate by the A or A2 test as specified in section 3.1 of this appendix.
b. If the manufacturer's installation instructions do not specify a test or operating conditions for charging or there are no manufacturer's instructions, use the following test(s):
(1) For air conditioners or cooling and heating heat pumps, use the A or A2 test.
(2) For cooling and heating heat pumps that do not operate in the H1 or H12 test (e.g. due to shut down by the unit limiting devices) when tested using the charge determined at the A or A2 test, and for heating-only heat pumps, use the H1 or H12 test.
2.2.5.3 Parameters to Set and Their Target Valuesa. Consult the manufacturer's installation instructions regarding which parameters (e.g., superheat) to set and their target values. If the instructions provide ranges of values, select target values equal to the midpoints of the provided ranges.
b. In the event of conflicting information between charging instructions (i.e., multiple conditions given for charge adjustment where all conditions specified cannot be met), follow the following hierarchy.
(1) For fixed orifice systems:
(i) Superheat
(ii) High side pressure or corresponding saturation or dew-point temperature
(iii) Low side pressure or corresponding saturation or dew-point temperature
(iv) Low side temperature
(v) High side temperature
(vi) Charge weight
(2) For expansion valve systems:
(i) Subcooling
(ii) High side pressure or corresponding saturation or dew-point temperature
(iii) Low side pressure or corresponding saturation or dew-point temperature
(iv) Approach temperature (difference between temperature of liquid leaving condenser and condenser average inlet air temperature)
(v) Charge weight
c. If there are no installation instructions and/or they do not provide parameters and target values, set superheat to a target value of 12 °F for fixed orifice systems or set subcooling to a target value of 10 °F for expansion valve systems.
2.2.5.4 Charging Tolerancesa. If the manufacturer's installation instructions specify tolerances on target values for the charging parameters, set the values within these tolerances.
b. Otherwise, set parameter values within the following test condition tolerances for the different charging parameters:
11. Superheat: ± 2.0 °F
12. Subcooling: ± 2.0 °F
13. High side pressure or corresponding saturation or dew point temperature: ± 4.0 psi or ± 1.0 °F
14. Low side pressure or corresponding saturation or dew point temperature: ± 2.0 psi or ± 0.8 °F
15. High side temperature: ± 2.0 °F
16. Low side temperature: ± 2.0 °F
17. Approach temperature: ± 1.0 °F
18. Charge weight: ± 2.0 ounce
2.2.5.5 Special Charging Instructionsa. Cooling and Heating Heat Pumps
If, using the initial charge set in the A or A2 test, the conditions are not within the range specified in manufacturer's installation instructions for the H1 or H12 test, make as small as possible an adjustment to obtain conditions for this test in the specified range. After this adjustment, recheck conditions in the A or A2 test to confirm that they are still within the specified range for the A or A2 test.
b. Single-Package Systemsi. Unless otherwise directed by the manufacturer's installation instructions, install one or more refrigerant line pressure gauges during the setup of the unit, located depending on the parameters used to verify or set charge, as described:
(1) Install a pressure gauge at the location of the service valve on the liquid line if charging is on the basis of subcooling, or high side pressure or corresponding saturation or dew point temperature;
(2) Install a pressure gauge at the location of the service valve on the suction line if charging is on the basis of superheat, or low side pressure or corresponding saturation or dew point temperature.
ii. Use methods for installing pressure gauge(s) at the required location(s) as indicated in manufacturer's instructions if specified.
2.2.5.6 Near-Azeotropic and Zeotropic RefrigerantsPerform charging of near-azeotropic and zeotropic refrigerants only with refrigerant in the liquid state.
2.2.5.7 Adjustment of Charge Between TestsAfter charging the system as described in this test procedure, use the set refrigerant charge for all tests used to determine performance. Do not adjust the refrigerant charge at any point during testing. If measurements indicate that refrigerant charge has leaked during the test, repair the refrigerant leak, repeat any necessary set-up steps, and repeat all tests.
2.3 Indoor Air Volume RatesIf a unit's controls allow for overspeeding the indoor blower (usually on a temporary basis), take the necessary steps to prevent overspeeding during all tests.
2.3.1 Cooling Testsa. Set indoor blower airflow-control settings (e.g., fan motor pin settings, fan motor speed) according to the requirements that are specified in section 3.1.4 of this appendix.
b. Express the Cooling full-load air volume rate, the Cooling Minimum Air Volume Rate, and the Cooling Intermediate Air Volume Rate in terms of standard air.
2.3.2 Heating Testsa. Set indoor blower airflow-control settings (e.g., fan motor pin settings, fan motor speed) according to the requirements that are specified in section 3.1.4 of this appendix.
b. Express the heating full-load air volume rate, the heating minimum air volume rate, the heating intermediate air volume rate, and the heating nominal air volume rate in terms of standard air.
2.4 Indoor Coil Inlet and Outlet Duct ConnectionsInsulate and/or construct the outlet plenum as described in section 2.4.1 of this appendix and, if installed, the inlet plenum described in section 2.4.2 of this appendix with thermal insulation having a nominal overall resistance (R-value) of at least 19 hr·ft 2 °F/Btu.
2.4.1 Outlet Plenum for the Indoor Unita. Attach a plenum to the outlet of the indoor coil. (Note: For some packaged systems, the indoor coil may be located in the outdoor test room.)
b. For systems having multiple indoor coils, or multiple indoor blowers within a single indoor section, attach a plenum to each indoor coil or indoor blower outlet. In order to reduce the number of required airflow measurement apparatuses (section 2.6 of this appendix), each such apparatus may serve multiple outlet plenums connected to a single common duct leading to the apparatus. More than one indoor test room may be used, which may use one or more common ducts leading to one or more airflow measurement apparatuses within each test room that contains multiple indoor coils. At the plane where each plenum enters a common duct, install an adjustable airflow damper and use it to equalize the static pressure in each plenum. The outlet air temperature grid(s) (section 2.5.4 of this appendix) and airflow measuring apparatus shall be located downstream of the inlet(s) to the common duct(s). For multiple-circuit (or multi-circuit) systems for which each indoor coil outlet is measured separately and its outlet plenum is not connected to a common duct connecting multiple outlet plenums, install the outlet air temperature grid and airflow measuring apparatus at each outlet plenum.
c. For small-duct, high-velocity systems, install an outlet plenum that has a diameter that is equal to or less than the value listed in Table 3. The limit depends only on the Cooling full-load air volume rate (see section 3.1.4.1.1 of this appendix) and is effective regardless of the flange dimensions on the outlet of the unit (or an air supply plenum adapter accessory, if installed in accordance with the manufacturer's installation instructions).
d. Add a static pressure tap to each face of the (each) outlet plenum, if rectangular, or at four evenly distributed locations along the circumference of an oval or round plenum. Create a manifold that connects the four static pressure taps. Figure 9 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3) shows allowed options for the manifold configuration. The cross-sectional dimensions of plenum must be equal to the dimensions of the indoor unit outlet. See Figures 7a, 7b, and 7c of ANSI/ASHRAE 37-2009 for the minimum length of the (each) outlet plenum and the locations for adding the static pressure taps for ducted blower coil indoor units and single-package systems. See Figure 8 of ANSI/ASHRAE 37-2009 for coil-only indoor units.
Table 3 - Size of Outlet Plenum for Small-Duct High-Velocity Indoor Units
| Cooling full-load air volume rate (scfm) |
Maximum diameter* of outlet
plenum (inches) |
|---|---|
| ≤500 | 6 |
| 501 to 700 | 7 |
| 701 to 900 | 8 |
| 901 to 1100 | 9 |
| 1101 to 1400 | 10 |
| 1401 to 1750 | 11 |
* If the outlet plenum is rectangular, calculate its equivalent diameter using (4A/P,) where A is the cross-sectional area and P is the perimeter of the rectangular plenum, and compare it to the listed maximum diameter.
Install an inlet plenum when testing a coil-only indoor unit, a ducted blower coil indoor unit, or a single-package system. See Figures 7b and 7c of ANSI/ASHRAE 37-2009 for cross-sectional dimensions, the minimum length of the inlet plenum, and the locations of the static-pressure taps for ducted blower coil indoor units and single-package systems. See Figure 8 of ANSI/ASHRAE 37-2009 for coil-only indoor units. The inlet plenum duct size shall equal the size of the inlet opening of the air-handling (blower coil) unit or furnace. For a ducted blower coil indoor unit the set up may omit the inlet plenum if an inlet airflow prevention device is installed with a straight internally unobstructed duct on its outlet end with a minimum length equal to 1.5 times the square root of the cross-sectional area of the indoor unit inlet. See section 2.1.5.2 of this appendix for requirements for the locations of static pressure taps built into the inlet airflow prevention device. For all of these arrangements, make a manifold that connects the four static-pressure taps using one of the three configurations specified in section 2.4.1.d. of this appendix. Never use an inlet plenum when testing a non-ducted system.
2.5 Indoor Coil Air Property Measurements and Airflow Prevention Devices.Follow instructions for indoor coil air property measurements as described in section 2.14 of this appendix, unless otherwise instructed in this section.
a. Measure the dry-bulb temperature and water vapor content of the air entering and leaving the indoor coil. If needed, use an air sampling device to divert air to a sensor(s) that measures the water vapor content of the air. See section 5.3 of ANSI/ASHRAE 41.1-2013 (incorporated by reference, see § 430.3) for guidance on constructing an air sampling device. No part of the air sampling device or the tubing transferring the sampled air to the sensor must be within two inches of the test chamber floor, and the transfer tubing must be insulated. The sampling device may also be used for measurement of dry bulb temperature by transferring the sampled air to a remotely located sensor(s). The air sampling device and the remotely located temperature sensor(s) may be used to determine the entering air dry bulb temperature during any test. The air sampling device and the remotely located sensor(s) may be used to determine the leaving air dry bulb temperature for all tests except:
(1) Cyclic tests; and
(2) Frost accumulation tests.
b. Install grids of temperature sensors to measure dry bulb temperatures of both the entering and leaving airstreams of the indoor unit. These grids of dry bulb temperature sensors may be used to measure average dry bulb temperature entering and leaving the indoor unit in all cases (as an alternative to the dry bulb sensor measuring the sampled air). The leaving airstream grid is required for measurement of average dry bulb temperature leaving the indoor unit for cyclic tests and frost accumulation tests. The grids are also required to measure the air temperature distribution of the entering and leaving airstreams as described in sections 3.1.8 of this appendix. Two such grids may be applied as a thermopile, to directly obtain the average temperature difference rather than directly measuring both entering and leaving average temperatures.
c. Use of airflow prevention devices. Use an inlet and outlet air damper box, or use an inlet upturned duct and an outlet air damper box when conducting one or both of the cyclic tests listed in sections 3.2 and 3.6 of this appendix on ducted systems. If not conducting any cyclic tests, an outlet air damper box is required when testing ducted and non-ducted heat pumps that cycle off the indoor blower during defrost cycles and there is no other means for preventing natural or forced convection through the indoor unit when the indoor blower is off. Never use an inlet damper box or an inlet upturned duct when testing non-ducted indoor units. An inlet upturned duct is a length of ductwork installed upstream from the inlet such that the indoor duct inlet opening, facing upwards, is sufficiently high to prevent natural convection transfer out of the duct. If an inlet upturned duct is used, install a dry bulb temperature sensor near the inlet opening of the indoor duct at a centerline location not higher than the lowest elevation of the duct edges at the inlet, and ensure that any pair of 5-minute averages of the dry bulb temperature at this location, measured at least every minute during the compressor OFF period of the cyclic test, do not differ by more than 1.0 °F.
2.5.1 Test Set-Up on the Inlet Side of the Indoor Coil: for Cases Where the Inlet Airflow Prevention Device is Installeda. Install an airflow prevention device as specified in section 2.5.1.1 or 2.5.1.2 of this appendix, whichever applies.
b. For an inlet damper box, locate the grid of entering air dry-bulb temperature sensors, if used, and the air sampling device, or the sensor used to measure the water vapor content of the inlet air, at a location immediately upstream of the damper box inlet. For an inlet upturned duct, locate the grid of entering air dry-bulb temperature sensors, if used, and the air sampling device, or the sensor used to measure the water vapor content of the inlet air, at a location at least one foot downstream from the beginning of the insulated portion of the duct but before the static pressure measurement.
2.5.1.1 If the section 2.4.2 inlet plenum is installed, construct the airflow prevention device having a cross-sectional flow area equal to or greater than the flow area of the inlet plenum. Install the airflow prevention device upstream of the inlet plenum and construct ductwork connecting it to the inlet plenum. If needed, use an adaptor plate or a transition duct section to connect the airflow prevention device with the inlet plenum. Insulate the ductwork and inlet plenum with thermal insulation that has a nominal overall resistance (R-value) of at least 19 hr · ft 2 · °F/Btu.
2.5.1.2 If the section 2.4.2 inlet plenum is not installed, construct the airflow prevention device having a cross-sectional flow area equal to or greater than the flow area of the air inlet of the indoor unit. Install the airflow prevention device immediately upstream of the inlet of the indoor unit. If needed, use an adaptor plate or a short transition duct section to connect the airflow prevention device with the unit's air inlet. Add static pressure taps at the center of each face of a rectangular airflow prevention device, or at four evenly distributed locations along the circumference of an oval or round airflow prevention device. Locate the pressure taps at a distance from the indoor unit inlet equal to 0.5 times the square root of the cross sectional area of the indoor unit inlet. This location must be between the damper and the inlet of the indoor unit, if a damper is used. Make a manifold that connects the four static pressure taps using one of the configurations shown in Figure 9 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3). Insulate the ductwork with thermal insulation that has a nominal overall resistance (R-value) of at least 19 hr·ft 2· °F/Btu.
2.5.2 Test Set-Up on the Inlet Side of the Indoor Unit: for Cases Where No Airflow Prevention Device is InstalledIf using the section 2.4.2 inlet plenum and a grid of dry bulb temperature sensors, mount the grid at a location upstream of the static pressure taps described in section 2.4.2 of this appendix, preferably at the entrance plane of the inlet plenum. If the section 2.4.2 inlet plenum is not used (i.e. for non-ducted units) locate a grid approximately 6 inches upstream of the indoor unit inlet. In the case of a system having multiple non-ducted indoor units, do this for each indoor unit. Position an air sampling device, or the sensor used to measure the water vapor content of the inlet air, immediately upstream of the (each) entering air dry-bulb temperature sensor grid. If a grid of sensors is not used, position the entering air sampling device (or the sensor used to measure the water vapor content of the inlet air) as if the grid were present.
2.5.3 Indoor Coil Static Pressure Difference MeasurementFabricate pressure taps meeting all requirements described in section 6.5.2 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3) and illustrated in Figure 2A of AMCA 210-2007 (incorporated by reference, see § 430.3), however, if adhering strictly to the description in section 6.5.2 of ANSI/ASHRAE 37-2009, the minimum pressure tap length of 2.5 times the inner diameter of Figure 2A of AMCA 210-2007 is waived. Use a differential pressure measuring instrument that is accurate to within ±0.01 inches of water and has a resolution of at least 0.01 inches of water to measure the static pressure difference between the indoor coil air inlet and outlet. Connect one side of the differential pressure instrument to the manifolded pressure taps installed in the outlet plenum. Connect the other side of the instrument to the manifolded pressure taps located in either the inlet plenum or incorporated within the airflow prevention device. For non-ducted systems that are tested with multiple outlet plenums, measure the static pressure within each outlet plenum relative to the surrounding atmosphere.
2.5.4 Test Set-Up on the Outlet Side of the Indoor Coila. Install an interconnecting duct between the outlet plenum described in section 2.4.1 of this appendix and the airflow measuring apparatus described below in section 2.6 of this appendix. The cross-sectional flow area of the interconnecting duct must be equal to or greater than the flow area of the outlet plenum or the common duct used when testing non-ducted units having multiple indoor coils. If needed, use adaptor plates or transition duct sections to allow the connections. To minimize leakage, tape joints within the interconnecting duct (and the outlet plenum). Construct or insulate the entire flow section with thermal insulation having a nominal overall resistance (R-value) of at least 19 hr·ft 2· °F/Btu.
b. Install a grid(s) of dry-bulb temperature sensors inside the interconnecting duct. Also, install an air sampling device, or the sensor(s) used to measure the water vapor content of the outlet air, inside the interconnecting duct. Locate the dry-bulb temperature grid(s) upstream of the air sampling device (or the in-duct sensor(s) used to measure the water vapor content of the outlet air). Turn off the sampler fan motor during the cyclic tests. Air leaving an indoor unit that is sampled by an air sampling device for remote water-vapor-content measurement must be returned to the interconnecting duct at a location:
(1) Downstream of the air sampling device;
(2) On the same side of the outlet air damper as the air sampling device; and
(3) Upstream of the section 2.6 airflow measuring apparatus.
2.5.4.1 Outlet Air Damper Box Placement and RequirementsIf using an outlet air damper box (see section 2.5 of this appendix), the leakage rate from the combination of the outlet plenum, the closed damper, and the duct section that connects these two components must not exceed 20 cubic feet per minute when a negative pressure of 1 inch of water column is maintained at the plenum's inlet.
2.5.4.2 Procedures to Minimize Temperature MaldistributionUse these procedures if necessary to correct temperature maldistributions. Install a mixing device(s) upstream of the outlet air, dry-bulb temperature grid (but downstream of the outlet plenum static pressure taps). Use a perforated screen located between the mixing device and the dry-bulb temperature grid, with a maximum open area of 40 percent. One or both items should help to meet the maximum outlet air temperature distribution specified in section 3.1.8 of this appendix. Mixing devices are described in sections 5.3.2 and 5.3.3 of ANSI/ASHRAE 41.1-2013 and section 5.2.2 of ASHRAE 41.2-1987 (RA 1992) (incorporated by reference, see § 430.3).
2.5.4.3 Minimizing Air LeakageFor small-duct, high-velocity systems, install an air damper near the end of the interconnecting duct, just prior to the transition to the airflow measuring apparatus of section 2.6 of this appendix. To minimize air leakage, adjust this damper such that the pressure in the receiving chamber of the airflow measuring apparatus is no more than 0.5 inch of water higher than the surrounding test room ambient. If applicable, in lieu of installing a separate damper, use the outlet air damper box of sections 2.5 and 2.5.4.1 of this appendix if it allows variable positioning. Also apply these steps to any conventional indoor blower unit that creates a static pressure within the receiving chamber of the airflow measuring apparatus that exceeds the test room ambient pressure by more than 0.5 inches of water column.
2.5.5 Dry Bulb Temperature Measurementa. Measure dry bulb temperatures as specified in sections 4, 5.3, 6, and 7 of ANSI/ASHRAE 41.1-2013 (incorporated by reference, see § 430.3).
b. Distribute the sensors of a dry-bulb temperature grid over the entire flow area. The required minimum is 9 sensors per grid.
2.5.6 Water Vapor Content MeasurementDetermine water vapor content by measuring dry-bulb temperature combined with the air wet-bulb temperature, dew point temperature, or relative humidity. If used, construct and apply wet-bulb temperature sensors as specified in sections 4, 5, 6, 7.2, 7.3, and 7.4 of ASHRAE 41.6-2014 (incorporated by reference, see § 430.3). The temperature sensor (wick removed) must be accurate to within ±0.2 °F. If used, apply dew point hygrometers as specified in sections 4, 5, 6, 7.1, and 7.4 of ASHRAE 41.6-2014. The dew point hygrometers must be accurate to within ±0.4 °F when operated at conditions that result in the evaluation of dew points above 35 °F. If used, a relative humidity (RH) meter must be accurate to within ±0.7% RH. Other means to determine the psychrometric state of air may be used as long as the measurement accuracy is equivalent to or better than the accuracy achieved from using a wet-bulb temperature sensor that meets the above specifications.
2.5.7 Air Damper Box Performance RequirementsIf used (see section 2.5 of this appendix), the air damper box(es) must be capable of being completely opened or completely closed within 10 seconds for each action.
2.6 Airflow Measuring Apparatusa. Fabricate and operate an airflow measuring apparatus as specified in section 6.2 and 6.3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3). Place the static pressure taps and position the diffusion baffle (settling means) relative to the chamber inlet as indicated in Figure 12 of AMCA 210-07 and/or Figure 14 of ASHRAE 41.2-1987 (RA 1992) (incorporated by reference, see § 430.3). When measuring the static pressure difference across nozzles and/or velocity pressure at nozzle throats using electronic pressure transducers and a data acquisition system, if high frequency fluctuations cause measurement variations to exceed the test tolerance limits specified in section 9.2 and Table 2 of ANSI/ASHRAE 37-2009, dampen the measurement system such that the time constant associated with response to a step change in measurement (time for the response to change 63% of the way from the initial output to the final output) is no longer than five seconds.
b. Connect the airflow measuring apparatus to the interconnecting duct section described in section 2.5.4 of this appendix. See sections 6.1.1, 6.1.2, and 6.1.4, and Figures 1, 2, and 4 of ANSI/ASHRAE 37-2009; and Figures D1, D2, and D4 of AHRI 210/240-2008 (incorporated by reference, see § 430.3) with Addendum 1 and 2 for illustrative examples of how the test apparatus may be applied within a complete laboratory set-up. Instead of following one of these examples, an alternative set-up may be used to handle the air leaving the airflow measuring apparatus and to supply properly conditioned air to the test unit's inlet. The alternative set-up, however, must not interfere with the prescribed means for measuring airflow rate, inlet and outlet air temperatures, inlet and outlet water vapor contents, and external static pressures, nor create abnormal conditions surrounding the test unit. (Note: Do not use an enclosure as described in section 6.1.3 of ANSI/ASHRAE 37-2009 when testing triple-split units.)
2.7 Electrical Voltage SupplyPerform all tests at the voltage specified in section 6.1.3.2 of AHRI 210/240-2008 (incorporated by reference, see § 430.3) for “Standard Rating Tests.” If either the indoor or the outdoor unit has a 208V or 200V nameplate voltage and the other unit has a 230V nameplate rating, select the voltage supply on the outdoor unit for testing. Otherwise, supply each unit with its own nameplate voltage. Measure the supply voltage at the terminals on the test unit using a volt meter that provides a reading that is accurate to within ±1.0 percent of the measured quantity.
2.8 Electrical Power and Energy Measurementsa. Use an integrating power (watt-hour) measuring system to determine the electrical energy or average electrical power supplied to all components of the air conditioner or heat pump (including auxiliary components such as controls, transformers, crankcase heater, integral condensate pump on non-ducted indoor units, etc.). The watt-hour measuring system must give readings that are accurate to within ±0.5 percent. For cyclic tests, this accuracy is required during both the ON and OFF cycles. Use either two different scales on the same watt-hour meter or two separate watt-hour meters. Activate the scale or meter having the lower power rating within 15 seconds after beginning an OFF cycle. Activate the scale or meter having the higher power rating within 15 seconds prior to beginning an ON cycle. For ducted blower coil systems, the ON cycle lasts from compressor ON to indoor blower OFF. For ducted coil-only systems, the ON cycle lasts from compressor ON to compressor OFF. For non-ducted units, the ON cycle lasts from indoor blower ON to indoor blower OFF. When testing air conditioners and heat pumps having a variable-speed compressor, avoid using an induction watt/watt-hour meter.
b. When performing section 3.5 and/or 3.8 cyclic tests on non-ducted units, provide instrumentation to determine the average electrical power consumption of the indoor blower motor to within ±1.0 percent. If required according to sections 3.3, 3.4, 3.7, 3.9.1 of this appendix, and/or 3.10 of this appendix, this same instrumentation requirement (to determine the average electrical power consumption of the indoor blower motor to within ±1.0 percent) applies when testing air conditioners and heat pumps having a variable-speed constant-air-volume-rate indoor blower or a variable-speed, variable-air-volume-rate indoor blower.
2.9 Time MeasurementsMake elapsed time measurements using an instrument that yields readings accurate to within ±0.2 percent.
2.10 Test Apparatus for the Secondary Space Conditioning Capacity MeasurementFor all tests, use the indoor air enthalpy method to measure the unit's capacity. This method uses the test set-up specified in sections 2.4 to 2.6 of this appendix. In addition, for all steady-state tests, conduct a second, independent measurement of capacity as described in section 3.1.1 of this appendix. For split systems, use one of the following secondary measurement methods: outdoor air enthalpy method, compressor calibration method, or refrigerant enthalpy method. For single-package units, use either the outdoor air enthalpy method or the compressor calibration method as the secondary measurement.
2.10.1 Outdoor Air Enthalpy Methoda. To make a secondary measurement of indoor space conditioning capacity using the outdoor air enthalpy method, do the following:
(1) Measure the electrical power consumption of the test unit;
(2) Measure the air-side capacity at the outdoor coil; and
(3) Apply a heat balance on the refrigerant cycle.
b. The test apparatus required for the outdoor air enthalpy method is a subset of the apparatus used for the indoor air enthalpy method. Required apparatus includes the following:
(1) On the outlet side, an outlet plenum containing static pressure taps (sections 2.4, 2.4.1, and 2.5.3 of this appendix),
(2) An airflow measuring apparatus (section 2.6 of this appendix),
(3) A duct section that connects these two components and itself contains the instrumentation for measuring the dry-bulb temperature and water vapor content of the air leaving the outdoor coil (sections 2.5.4, 2.5.5, and 2.5.6 of this appendix), and
(4) On the inlet side, a sampling device and temperature grid (section 2.11.b of this appendix).
c. During the free outdoor air tests described in sections 3.11.1 and 3.11.1.1 of this appendix, measure the evaporator and condenser temperatures or pressures. On both the outdoor coil and the indoor coil, solder a thermocouple onto a return bend located at or near the midpoint of each coil or at points not affected by vapor superheat or liquid subcooling. Alternatively, if the test unit is not sensitive to the refrigerant charge, install pressure gages to the access valves or to ports created from tapping into the suction and discharge lines according to sections 7.4.2 and 8.2.5 of ANSI/ASHRAE 37-2009. Use this alternative approach when testing a unit charged with a zeotropic refrigerant having a temperature glide in excess of 1 °F at the specified test conditions.
2.10.2 Compressor Calibration MethodMeasure refrigerant pressures and temperatures to determine the evaporator superheat and the enthalpy of the refrigerant that enters and exits the indoor coil. Determine refrigerant flow rate or, when the superheat of the refrigerant leaving the evaporator is less than 5 °F, total capacity from separate calibration tests conducted under identical operating conditions. When using this method, install instrumentation and measure refrigerant properties according to section 7.4.2 and 8.2.5 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3). If removing the refrigerant before applying refrigerant lines and subsequently recharging, use the steps in 7.4.2 of ANSI/ASHRAE 37-2009 in addition to the methods of section 2.2.5 of this appendix to confirm the refrigerant charge. Use refrigerant temperature and pressure measuring instruments that meet the specifications given in sections 5.1.1 and 5.2 of ANSI/ASHRAE 37-2009.
2.10.3 Refrigerant Enthalpy MethodFor this method, calculate space conditioning capacity by determining the refrigerant enthalpy change for the indoor coil and directly measuring the refrigerant flow rate. Use section 7.5.2 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3) for the requirements for this method, including the additional instrumentation requirements, and information on placing the flow meter and a sight glass. Use refrigerant temperature, pressure, and flow measuring instruments that meet the specifications given in sections 5.1.1, 5.2, and 5.5.1 of ANSI/ASHRAE 37-2009. Refrigerant flow measurement device(s), if used, must be either elevated at least two feet from the test chamber floor or placed upon insulating material having a total thermal resistance of at least R-12 and extending at least one foot laterally beyond each side of the device(s)' exposed surfaces.
2.11 Measurement of Test Room Ambient ConditionsFollow instructions for setting up air sampling device and aspirating psychrometer as described in section 2.14 of this appendix, unless otherwise instructed in this section.
a. If using a test set-up where air is ducted directly from the conditioning apparatus to the indoor coil inlet (see Figure 2, Loop Air-Enthalpy Test Method Arrangement, of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3)), add instrumentation to permit measurement of the indoor test room dry-bulb temperature.
b. On the outdoor side, use one of the following two approaches, except that approach (1) is required for all evaporatively cooled units and units that transfer condensate to the outdoor unit for evaporation using condenser heat.
(1) Use sampling tree air collection on all air-inlet surfaces of the outdoor unit.
(2) Use sampling tree air collection on one or more faces of the outdoor unit and demonstrate air temperature uniformity as follows. Install a grid of evenly distributed thermocouples on each air-permitting face on the inlet of the outdoor unit. Install the thermocouples on the air sampling device, locate them individually or attach them to a wire structure. If not installed on the air sampling device, install the thermocouple grid 6 to 24 inches from the unit. Evenly space the thermocouples across the coil inlet surface and install them to avoid sampling of discharge air or blockage of air recirculation. The grid of thermocouples must provide at least 16 measuring points per face or one measurement per square foot of inlet face area, whichever is less. Construct this grid and use as per section 5.3 of ANSI/ASHRAE 41.1-2013 (incorporated by reference, see § 430.3). The maximum difference between the average temperatures measured during the test period of any two pairs of these individual thermocouples located at any of the faces of the inlet of the outdoor unit, must not exceed 2.0 °F, otherwise use approach (1).
Locate the air sampling devices at the geometric center of each side; the branches may be oriented either parallel or perpendicular to the longer edges of the air inlet area. Size the air sampling devices in the outdoor air inlet location such that they cover at least 75% of the face area of the side of the coil that they are measuring.
Review air distribution at the test facility point of supply to the unit and remediate as necessary prior to the beginning of testing. Mixing fans can be used to ensure adequate air distribution in the test room. If used, orient mixing fans such that they are pointed away from the air intake so that the mixing fan exhaust does not affect the outdoor coil air volume rate. Particular attention should be given to prevent the mixing fans from affecting (enhancing or limiting) recirculation of condenser fan exhaust air back through the unit. Any fan used to enhance test room air mixing shall not cause air velocities in the vicinity of the test unit to exceed 500 feet per minute.
The air sampling device may be larger than the face area of the side being measured. Take care, however, to prevent discharge air from being sampled. If an air sampling device dimension extends beyond the inlet area of the unit, block holes in the air sampling device to prevent sampling of discharge air. Holes can be blocked to reduce the region of coverage of the intake holes both in the direction of the trunk axis or perpendicular to the trunk axis. For intake hole region reduction in the direction of the trunk axis, block holes of one or more adjacent pairs of branches (the branches of a pair connect opposite each other at the same trunk location) at either the outlet end or the closed end of the trunk. For intake hole region reduction perpendicular to the trunk axis, block off the same number of holes on each branch on both sides of the trunk.
Connect a maximum of four (4) air sampling devices to each aspirating psychrometer. In order to proportionately divide the flow stream for multiple air sampling devices for a given aspirating psychrometer, the tubing or conduit conveying sampled air to the psychrometer must be of equivalent lengths for each air sampling device. Preferentially, the air sampling device should be hard connected to the aspirating psychrometer, but if space constraints do not allow this, the assembly shall have a means of allowing a flexible tube to connect the air sampling device to the aspirating psychrometer. Insulate and route the tubing or conduit to prevent heat transfer to the air stream. Insulate any surface of the air conveying tubing in contact with surrounding air at a different temperature than the sampled air with thermal insulation with a nominal thermal resistance (R-value) of at least 19 hr • ft 2 • °F/Btu. Alternatively the conduit may have lower thermal resistance if additional sensor(s) are used to measure dry bulb temperature at the outlet of each air sampling device. No part of the air sampling device or the tubing conducting the sampled air to the sensors may be within two inches of the test chamber floor.
Take pairs of measurements (e.g. dry bulb temperature and wet bulb temperature) used to determine water vapor content of sampled air in the same location.
2.12 Measurement of Indoor Blower SpeedWhen required, measure fan speed using a revolution counter, tachometer, or stroboscope that gives readings accurate to within ±1.0 percent.
2.13 Measurement of Barometric PressureDetermine the average barometric pressure during each test. Use an instrument that meets the requirements specified in section 5.2 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3).
2.14 Air Sampling Device and Aspirating Psychrometer RequirementsMake air temperature measurements in accordance with ANSI/ASHRAE 41.1-2013 (incorporated by reference, see § 430.3), unless otherwise instructed in this section.
2.14.1 Air Sampling Device RequirementsThe air sampling device is intended to draw in a sample of the air at the critical locations of a unit under test. Construct the device from stainless steel, plastic or other suitable, durable materials. It shall have a main flow trunk tube with a series of branch tubes connected to the trunk tube. Holes must be on the side of the sampler facing the upstream direction of the air source. Use other sizes and rectangular shapes, and scale them accordingly with the following guidelines:
1. Minimum hole density of 6 holes per square foot of area to be sampled.
2. Sampler branch tube pitch (spacing) of 6 ± 3 in.
3. Manifold trunk to branch diameter ratio having a minimum of 3:1 ratio.
4. Distribute hole pitch (spacing) equally over the branch ( 1/2 pitch from the closed end to the nearest hole).
5. Maximum individual hole to branch diameter ratio of 1:2 (1:3 preferred).
The minimum average velocity through the air sampling device holes must be 2.5 ft/s as determined by evaluating the sum of the open area of the holes as compared to the flow area in the aspirating psychrometer.
2.14.2 Aspirating PsychrometerThe psychrometer consists of a flow section and a fan to draw air through the flow section and measures an average value of the sampled air stream. At a minimum, the flow section shall have a means for measuring the dry bulb temperature (typically, a resistance temperature device (RTD) and a means for measuring the humidity (RTD with wetted sock, chilled mirror hygrometer, or relative humidity sensor). The aspirating psychrometer shall include a fan that either can be adjusted manually or automatically to maintain required velocity across the sensors.
Construct the psychrometer using suitable material which may be plastic (such as polycarbonate), aluminum or other metallic materials. Construct all psychrometers for a given system being tested, using the same material. Design the psychrometers such that radiant heat from the motor (for driving the fan that draws sampled air through the psychrometer) does not affect sensor measurements. For aspirating psychrometers, velocity across the wet bulb sensor must be 1000 ± 200 ft/min. For all other psychrometers, velocity must be as specified by the sensor manufacturer.
3 Testing Procedures 3.1 General RequirementsIf, during the testing process, an equipment set-up adjustment is made that would have altered the performance of the unit during any already completed test, then repeat all tests affected by the adjustment. For cyclic tests, instead of maintaining an air volume rate, for each airflow nozzle, maintain the static pressure difference or velocity pressure during an ON period at the same pressure difference or velocity pressure as measured during the steady-state test conducted at the same test conditions.
Use the testing procedures in this section to collect the data used for calculating
(1) Performance metrics for central air conditioners and heat pumps during the cooling season;
(2) Performance metrics for heat pumps during the heating season; and
(3) Power consumption metric(s) for central air conditioners and heat pumps during the off mode season(s).
3.1.1 Primary and Secondary Test MethodsFor all tests, use the indoor air enthalpy method test apparatus to determine the unit's space conditioning capacity. The procedure and data collected, however, differ slightly depending upon whether the test is a steady-state test, a cyclic test, or a frost accumulation test. The following sections described these differences. For full-capacity cooling-mode test and (for a heat pump) the full-capacity heating-mode test, use one of the acceptable secondary methods specified in section 2.10 of this appendix to determine indoor space conditioning capacity. Calculate this secondary check of capacity according to section 3.11 of this appendix. The two capacity measurements must agree to within 6 percent to constitute a valid test. For this capacity comparison, use the Indoor Air Enthalpy Method capacity that is calculated in section 7.3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3) (and, if testing a coil-only system, compare capacities before making the after-test fan heat adjustments described in section 3.3, 3.4, 3.7, and 3.10 of this appendix). However, include the appropriate section 3.3 to 3.5 and 3.7 to 3.10 fan heat adjustments within the indoor air enthalpy method capacities used for the section 4 seasonal calculations of this appendix.
3.1.2 Manufacturer-Provided Equipment OverridesWhere needed, the manufacturer must provide a means for overriding the controls of the test unit so that the compressor(s) operates at the specified speed or capacity and the indoor blower operates at the specified speed or delivers the specified air volume rate.
3.1.3 Airflow Through the Outdoor CoilFor all tests, meet the requirements given in section 6.1.3.4 of AHRI 210/240-2008 (incorporated by reference, see § 430.3) when obtaining the airflow through the outdoor coil.
3.1.3.1 Double-DuctedFor products intended to be installed with the outdoor airflow ducted, install the unit with outdoor coil ductwork installed per manufacturer installation instructions. The unit must operate between 0.10 and 0.15 in H2O external static pressure. Make external static pressure measurements in accordance with ANSI/ASHRAE 37-2009 section 6.4 and 6.5.
3.1.4 Airflow Through the Indoor CoilDetermine airflow setting(s) before testing begins. Unless otherwise specified within this or its subsections, make no changes to the airflow setting(s) after initiation of testing.
3.1.4.1 Cooling Full-Load Air Volume Rate 3.1.4.1.1 Cooling Full-Load Air Volume Rate for Ducted UnitsIdentify the certified Cooling full-load air volume rate and certified instructions for setting fan speed or controls. If there is no certified Cooling full-load air volume rate, use a value equal to the certified cooling capacity of the unit times 400 scfm per 12,000 Btu/h. If there are no instructions for setting fan speed or controls, use the as-shipped settings. Use the following procedure to confirm and, if necessary, adjust the Cooling full-load air volume rate and the fan speed or control settings to meet each test procedure requirement:
a. For all ducted blower coil systems, except those having a constant-air-volume-rate indoor blower:
Step (1) Operate the unit under conditions specified for the A (for single-stage units) or A2 test using the certified fan speed or controls settings, and adjust the exhaust fan of the airflow measuring apparatus to achieve the certified Cooling full-load air volume rate;
Step (2) Measure the external static pressure;
Step (3) If this external static pressure is equal to or greater than the applicable minimum external static pressure cited in Table 4, the pressure requirement is satisfied; proceed to step 7 of this section. If this external static pressure is not equal to or greater than the applicable minimum external static pressure cited in Table 4, proceed to step 4 of this section;
Step (4) Increase the external static pressure by adjusting the exhaust fan of the airflow measuring apparatus until either
(i) The applicable Table 4 minimum is equaled or
(ii) The measured air volume rate equals 90 percent or less of the Cooling full-load air volume rate, whichever occurs first;
Step (5) If the conditions of step 4 (i) of this section occur first, the pressure requirement is satisfied; proceed to step 7 of this section. If the conditions of step 4 (ii) of this section occur first, proceed to step 6 of this section;
Step (6) Make an incremental change to the setup of the indoor blower (e.g., next highest fan motor pin setting, next highest fan motor speed) and repeat the evaluation process beginning above, at step 1 of this section. If the indoor blower setup cannot be further changed, increase the external static pressure by adjusting the exhaust fan of the airflow measuring apparatus until the applicable Table 4 minimum is equaled; proceed to step 7 of this section;
Step (7) The airflow constraints have been satisfied. Use the measured air volume rate as the Cooling full-load air volume rate. Use the final fan speed or control settings for all tests that use the Cooling full-load air volume rate.
b. For ducted blower coil systems with a constant-air-volume-rate indoor blower. For all tests that specify the Cooling full-load air volume rate, obtain an external static pressure as close to (but not less than) the applicable Table 4 value that does not cause automatic shutdown of the indoor blower or air volume rate variation QVar, defined as follows, greater than 10 percent.
Where:
Qmax = maximum measured airflow value Qmin = minimum measured
airflow value QVar = airflow variance, percent
Additional test steps as described in section 3.3.e of this appendix are required if the measured external static pressure exceeds the target value by more than 0.03 inches of water.
c. For coil-only indoor units. For the A or A2 Test, (exclusively), the pressure drop across the indoor coil assembly must not exceed 0.30 inches of water. If this pressure drop is exceeded, reduce the air volume rate until the measured pressure drop equals the specified maximum. Use this reduced air volume rate for all tests that require the Cooling full-load air volume rate.
Table 4 - Minimum External Static Pressure for Ducted Blower Coil Systems
| Product variety | Minimum external static pressure (in. wc.) |
|---|---|
| Conventional (i.e., all central air conditioners and heat pumps not otherwise listed in this table) | 0.50 |
| Ceiling-mount and Wall-mount | 0.30 |
| Mobile Home | 0.30 |
| Low Static | 0.10 |
| Mid Static | 0.30 |
| Small Duct, High Velocity | 1.15 |
| Space-constrained | 0.30 |
1 For ducted units tested without an air filter installed, increase the applicable tabular value by 0.08 inches of water.
2 See section 1.2, Definitions, to determine for which Table 4 product variety and associated minimum external static pressure requirement equipment qualifies.
3 If a closed-loop, air-enthalpy test apparatus is used on the indoor side, limit the resistance to airflow on the inlet side of the indoor blower coil to a maximum value of 0.1 inch of water.
d. For ducted systems having multiple indoor blowers within a single indoor section, obtain the full-load air volume rate with all indoor blowers operating unless prevented by the controls of the unit. In such cases, turn on the maximum number of indoor blowers permitted by the unit's controls. Where more than one option exists for meeting this “on” indoor blower requirement, which indoor blower(s) are turned on must match that specified in the certification report. Conduct section 3.1.4.1.1 setup steps for each indoor blower separately. If two or more indoor blowers are connected to a common duct as per section 2.4.1 of this appendix, temporarily divert their air volume to the test room when confirming or adjusting the setup configuration of individual indoor blowers. The allocation of the system's full-load air volume rate assigned to each “on” indoor blower must match that specified by the manufacturer in the certification report.
3.1.4.1.2 Cooling Full-Load Air Volume Rate for Non-Ducted UnitsFor non-ducted units, the Cooling full-load air volume rate is the air volume rate that results during each test when the unit is operated at an external static pressure of zero inches of water.
3.1.4.2 Cooling Minimum Air Volume RateIdentify the certified cooling minimum air volume rate and certified instructions for setting fan speed or controls. If there is no certified cooling minimum air volume rate, use the final indoor blower control settings as determined when setting the cooling full-load air volume rate, and readjust the exhaust fan of the airflow measuring apparatus if necessary to reset to the cooling full load air volume obtained in section 3.1.4.1 of this appendix. Otherwise, calculate the target external static pressure and follow instructions a, b, c, d, or e of this section. The target external static pressure, ΔPst_i, for any test “i” with a specified air volume rate not equal to the Cooling full-load air volume rate is determined as follows:
Where:
ΔPst_i = target minimum external static pressure for test i;
ΔPst_full = minimum external static pressure for test A or A2
(Table 4); Qi = air volume rate for test i; and Qfull = Cooling
full-load air volume rate as measured after setting and/or
adjustment as described in section 3.1.4.1.1 of this appendix.
a. For a ducted blower coil system without a constant-air-volume indoor blower, adjust for external static pressure as follows:
Step (1) Operate the unit under conditions specified for the B1 test using the certified fan speed or controls settings, and adjust the exhaust fan of the airflow measuring apparatus to achieve the certified cooling minimum air volume rate;
Step (2) Measure the external static pressure;
Step (3) If this pressure is equal to or greater than the minimum external static pressure computed above, the pressure requirement is satisfied; proceed to step 7 of this section. If this pressure is not equal to or greater than the minimum external static pressure computed above, proceed to step 4 of this section;
Step (4) Increase the external static pressure by adjusting the exhaust fan of the airflow measuring apparatus until either
(i) The pressure is equal to the minimum external static pressure computed above or
(ii) The measured air volume rate equals 90 percent or less of the cooling minimum air volume rate, whichever occurs first;
Step (5) If the conditions of step 4 (i) of this section occur first, the pressure requirement is satisfied; proceed to step 7 of this section. If the conditions of step 4 (ii) of this section occur first, proceed to step 6 of this section;
Step (6) Make an incremental change to the setup of the indoor blower (e.g., next highest fan motor pin setting, next highest fan motor speed) and repeat the evaluation process beginning above, at step 1 of this section. If the indoor blower setup cannot be further changed, increase the external static pressure by adjusting the exhaust fan of the airflow measuring apparatus until it equals the minimum external static pressure computed above; proceed to step 7 of this section;
Step (7) The airflow constraints have been satisfied. Use the measured air volume rate as the cooling minimum air volume rate. Use the final fan speed or control settings for all tests that use the cooling minimum air volume rate.
b. For ducted units with constant-air-volume indoor blowers, conduct all tests that specify the cooling minimum air volume rate - (i.e., the A1, B1, C1, F1, and G1 Tests) - at an external static pressure that does not cause an automatic shutdown of the indoor blower or air volume rate variation QVar, defined in section 3.1.4.1.1.b of this appendix, greater than 10 percent, while being as close to, but not less than the target minimum external static pressure. Additional test steps as described in section 3.3.e of this appendix are required if the measured external static pressure exceeds the target value by more than 0.03 inches of water.
c. For ducted two-capacity coil-only systems, the cooling minimum air volume rate is the higher of -
(1) The rate specified by the installation instructions included with the unit by the manufacturer; or
(2) 75 percent of the cooling full-load air volume rate. During the laboratory tests on a coil-only (fanless) system, obtain this cooling minimum air volume rate regardless of the pressure drop across the indoor coil assembly.
d. For non-ducted units, the cooling minimum air volume rate is the air volume rate that results during each test when the unit operates at an external static pressure of zero inches of water and at the indoor blower setting used at low compressor capacity (two-capacity system) or minimum compressor speed (variable-speed system). For units having a single-speed compressor and a variable-speed variable-air-volume-rate indoor blower, use the lowest fan setting allowed for cooling.
e. For ducted systems having multiple indoor blowers within a single indoor section, operate the indoor blowers such that the lowest air volume rate allowed by the unit's controls is obtained when operating the lone single-speed compressor or when operating at low compressor capacity while meeting the requirements of section 2.2.3.2 of this appendix for the minimum number of blowers that must be turned off. Using the target external static pressure and the certified air volume rates, follow the procedures described in section 3.1.4.2.a of this appendix if the indoor blowers are not constant-air-volume indoor blowers or as described in section 3.1.4.2.b of this appendix if the indoor blowers are not constant-air-volume indoor blowers. The sum of the individual “on” indoor blowers' air volume rates is the cooling minimum air volume rate for the system.
3.1.4.3 Cooling Intermediate Air Volume RateIdentify the certified cooling intermediate air volume rate and certified instructions for setting fan speed or controls. If there is no certified cooling intermediate air volume rate, use the final indoor blower control settings as determined when setting the cooling full load air volume rate, and readjust the exhaust fan of the airflow measuring apparatus if necessary to reset to the cooling full load air volume obtained in section 3.1.4.1 of this appendix. Otherwise, calculate target minimum external static pressure as described in section 3.1.4.2 of this appendix, and set the air volume rate as follows.
a. For a ducted blower coil system without a constant-air-volume indoor blower, adjust for external static pressure as described in section 3.1.4.2.a of this appendix for cooling minimum air volume rate.
b. For a ducted blower coil system with a constant-air-volume indoor blower, conduct the EV Test at an external static pressure that does not cause an automatic shutdown of the indoor blower or air volume rate variation QVar, defined in section 3.1.4.1.1.b of this appendix, greater than 10 percent, while being as close to, but not less than the target minimum external static pressure. Additional test steps as described in section 3.3.e of this appendix are required if the measured external static pressure exceeds the target value by more than 0.03 inches of water.
c. For non-ducted units, the cooling intermediate air volume rate is the air volume rate that results when the unit operates at an external static pressure of zero inches of water and at the fan speed selected by the controls of the unit for the EV Test conditions.
3.1.4.4 Heating Full-Load Air Volume Rate 3.1.4.4.1 Ducted Heat Pumps Where the Heating and Cooling Full-Load Air Volume Rates Are the Samea. Use the Cooling full-load air volume rate as the heating full-load air volume rate for:
(1) Ducted blower coil system heat pumps that do not have a constant-air-volume indoor blower, and that operate at the same airflow-control setting during both the A (or A2) and the H1 (or H12) Tests;
(2) Ducted blower coil system heat pumps with constant-air-flow indoor blowers that provide the same airflow for the A (or A2) and the H1 (or H12) Tests; and
(3) Ducted heat pumps that are tested with a coil-only indoor unit (except two-capacity northern heat pumps that are tested only at low capacity cooling - see section 3.1.4.4.2 of this appendix).
b. For heat pumps that meet the above criteria “1” and “3,” no minimum requirements apply to the measured external or internal, respectively, static pressure. Use the final indoor blower control settings as determined when setting the Cooling full-load air volume rate, and readjust the exhaust fan of the airflow measuring apparatus if necessary to reset to the cooling full-load air volume obtained in section 3.1.4.1 of this appendix. For heat pumps that meet the above criterion “2,” test at an external static pressure that does not cause an automatic shutdown of the indoor blower or air volume rate variation QVar, defined in section 3.1.4.1.1.b of this appendix, greater than 10 percent, while being as close to, but not less than, the same Table 4 minimum external static pressure as was specified for the A (or A2) cooling mode test. Additional test steps as described in section 3.9.1.c of this appendix are required if the measured external static pressure exceeds the target value by more than 0.03 inches of water.
3.1.4.4.2 Ducted Heat Pumps Where the Heating and Cooling Full-Load Air Volume Rates Are Different Due to Changes in Indoor Blower Operation, i.e. Speed Adjustment by the System ControlsIdentify the certified heating full-load air volume rate and certified instructions for setting fan speed or controls. If there is no certified heating full-load air volume rate, use the final indoor blower control settings as determined when setting the cooling full-load air volume rate, and readjust the exhaust fan of the airflow measuring apparatus if necessary to reset to the cooling full-load air volume obtained in section 3.1.4.1 of this appendix. Otherwise, calculate the target minimum external static pressure as described in section 3.1.4.2 of this appendix and set the air volume rate as follows.
a. For ducted blower coil system heat pumps that do not have a constant-air-volume indoor blower, adjust for external static pressure as described in section 3.1.4.2.a of this appendix for cooling minimum air volume rate.
b. For ducted heat pumps tested with constant-air-volume indoor blowers installed, conduct all tests that specify the heating full-load air volume rate at an external static pressure that does not cause an automatic shutdown of the indoor blower or air volume rate variation QVar, defined in section 3.1.4.1.1.b of this appendix, greater than 10 percent, while being as close to, but not less than the target minimum external static pressure. Additional test steps as described in section 3.9.1.c of this appendix are required if the measured external static pressure exceeds the target value by more than 0.03 inches of water.
c. When testing ducted, two-capacity blower coil system northern heat pumps (see section 1.2 of this appendix, Definitions), use the appropriate approach of the above two cases. For coil-only system northern heat pumps, the heating full-load air volume rate is the lesser of the rate specified by the manufacturer in the installation instructions included with the unit or 133 percent of the cooling full-load air volume rate. For this latter case, obtain the heating full-load air volume rate regardless of the pressure drop across the indoor coil assembly.
d. For ducted systems having multiple indoor blowers within a single indoor section, obtain the heating full-load air volume rate using the same “on” indoor blowers as used for the Cooling full-load air volume rate. Using the target external static pressure and the certified air volume rates, follow the procedures as described in section 3.1.4.4.2.a of this appendix if the indoor blowers are not constant-air-volume indoor blowers or as described in section 3.1.4.4.2.b of this appendix if the indoor blowers are constant-air-volume indoor blowers. The sum of the individual “on” indoor blowers' air volume rates is the heating full-load air volume rate for the system.
3.1.4.4.3 Ducted Heating-Only Heat PumpsIdentify the certified heating full-load air volume rate and certified instructions for setting fan speed or controls. If there is no certified heating full-load air volume rate, use a value equal to the certified heating capacity of the unit times 400 scfm per 12,000 Btu/h. If there are no instructions for setting fan speed or controls, use the as-shipped settings.
a. For all ducted heating-only blower coil system heat pumps, except those having a constant-air-volume-rate indoor blower. Conduct the following steps only during the first test, the H1 or H12 test:
Step (1) Adjust the exhaust fan of the airflow measuring apparatus to achieve the certified heating full-load air volume rate.
Step (2) Measure the external static pressure.
Step (3) If this pressure is equal to or greater than the Table 4 minimum external static pressure that applies given the heating-only heat pump's rated heating capacity, the pressure requirement is satisfied; proceed to step 7 of this section. If this pressure is not equal to or greater than the applicable Table 4 minimum external static pressure, proceed to step 4 of this section;
Step (4) Increase the external static pressure by adjusting the exhaust fan of the airflow measuring apparatus until either -
(i) The pressure is equal to the applicable Table 4 minimum external static pressure; or
(ii) The measured air volume rate equals 90 percent or less of the heating full-load air volume rate, whichever occurs first;
Step (5) If the conditions of step 4 (i) of this section occur first, the pressure requirement is satisfied; proceed to step 7 of this section. If the conditions of step 4 (ii) of this section occur first, proceed to step 6 of this section;
Step (6) Make an incremental change to the setup of the indoor blower (e.g., next highest fan motor pin setting, next highest fan motor speed) and repeat the evaluation process beginning above, at step 1 of this section. If the indoor blower setup cannot be further changed, increase the external static pressure by adjusting the exhaust fan of the airflow measuring apparatus until it equals the applicable Table 4 minimum external static pressure; proceed to step 7 of this section;
Step (7) The airflow constraints have been satisfied. Use the measured air volume rate as the heating full-load air volume rate. Use the final fan speed or control settings for all tests that use the heating full-load air volume rate.
b. For ducted heating-only blower coil system heat pumps having a constant-air-volume-rate indoor blower. For all tests that specify the heating full-load air volume rate, obtain an external static pressure that does not cause an automatic shutdown of the indoor blower or air volume rate variation QVar, defined in section 3.1.4.1.1.b of this section, greater than 10 percent, while being as close to, but not less than, the applicable Table 4 minimum. Additional test steps as described in section 3.9.1.c of this appendix are required if the measured external static pressure exceeds the target value by more than 0.03 inches of water.
c. For ducted heating-only coil-only system heat pumps in the H1 or H12 Test, (exclusively), the pressure drop across the indoor coil assembly must not exceed 0.30 inches of water. If this pressure drop is exceeded, reduce the air volume rate until the measured pressure drop equals the specified maximum. Use this reduced air volume rate for all tests that require the heating full-load air volume rate.
3.1.4.4.4 Non-Ducted Heat Pumps, Including Non-Ducted Heating-Only Heat PumpsFor non-ducted heat pumps, the heating full-load air volume rate is the air volume rate that results during each test when the unit operates at an external static pressure of zero inches of water.
3.1.4.5 Heating Minimum Air Volume Rate 3.1.4.5.1 Ducted Heat Pumps Where the Heating and Cooling Minimum Air Volume Rates are the Samea. Use the cooling minimum air volume rate as the heating minimum air volume rate for:
(1) Ducted blower coil system heat pumps that do not have a constant-air-volume indoor blower, and that operates at the same airflow-control setting during both the A1 and the H11 tests;
(2) Ducted blower coil system heat pumps with constant-air-flow indoor blowers installed that provide the same airflow for the A1 and the H11 Tests; and
(3) Ducted coil-only system heat pumps.
b. For heat pumps that meet the above criteria “1” and “3,” no minimum requirements apply to the measured external or internal, respectively, static pressure. Use the final indoor blower control settings as determined when setting the cooling minimum air volume rate, and readjust the exhaust fan of the airflow measuring apparatus if necessary to reset to the cooling minimum air volume rate obtained in section 3.1.4.2 of this appendix. For heat pumps that meet the above criterion “2,” test at an external static pressure that does not cause an automatic shutdown of the indoor blower or air volume rate variation QVar, defined in section 3.1.4.1.1.b, greater than 10 percent, while being as close to, but not less than, the same target minimum external static pressure as was specified for the A1 cooling mode test. Additional test steps as described in section 3.9.1.c of this appendix are required if the measured external static pressure exceeds the target value by more than 0.03 inches of water.
3.1.4.5.2 Ducted Heat Pumps Where the Heating and Cooling Minimum Air Volume Rates Are Different Due to Indoor Blower Operation, i.e. Speed Adjustment by the System ControlsIdentify the certified heating minimum air volume rate and certified instructions for setting fan speed or controls. If there is no certified heating minimum air volume rate, use the final indoor blower control settings as determined when setting the cooling minimum air volume rate, and readjust the exhaust fan of the airflow measuring apparatus if necessary to reset to the cooling minimum air volume obtained in section 3.1.4.2 of this appendix. Otherwise, calculate the target minimum external static pressure as described in section 3.1.4.2 of this appendix.
a. For ducted blower coil system heat pumps that do not have a constant-air-volume indoor blower, adjust for external static pressure as described in section 3.1.4.2.a of this appendix for cooling minimum air volume rate.
b. For ducted heat pumps tested with constant-air-volume indoor blowers installed, conduct all tests that specify the heating minimum air volume rate - (i.e., the H01, H11, H21, and H31 Tests) - at an external static pressure that does not cause an automatic shutdown of the indoor blower while being as close to, but not less than the air volume rate variation QVar, defined in section 3.1.4.1.1.b of this appendix, greater than 10 percent, while being as close to, but not less than the target minimum external static pressure. Additional test steps as described in section 3.9.1.c of this appendix are required if the measured external static pressure exceeds the target value by more than 0.03 inches of water.
c. For ducted two-capacity blower coil system northern heat pumps, use the appropriate approach of the above two cases.
d. For ducted two-capacity coil-only system heat pumps, use the cooling minimum air volume rate as the heating minimum air volume rate. For ducted two-capacity coil-only system northern heat pumps, use the cooling full-load air volume rate as the heating minimum air volume rate. For ducted two-capacity heating-only coil-only system heat pumps, the heating minimum air volume rate is the higher of the rate specified by the manufacturer in the test setup instructions included with the unit or 75 percent of the heating full-load air volume rate. During the laboratory tests on a coil-only system, obtain the heating minimum air volume rate without regard to the pressure drop across the indoor coil assembly.
e. For non-ducted heat pumps, the heating minimum air volume rate is the air volume rate that results during each test when the unit operates at an external static pressure of zero inches of water and at the indoor blower setting used at low compressor capacity (two-capacity system) or minimum compressor speed (variable-speed system). For units having a single-speed compressor and a variable-speed, variable-air-volume-rate indoor blower, use the lowest fan setting allowed for heating.
f. For ducted systems with multiple indoor blowers within a single indoor section, obtain the heating minimum air volume rate using the same “on” indoor blowers as used for the cooling minimum air volume rate. Using the target external static pressure and the certified air volume rates, follow the procedures as described in section 3.1.4.5.2.a of this appendix if the indoor blowers are not constant-air-volume indoor blowers or as described in section 3.1.4.5.2.b of this appendix if the indoor blowers are constant-air-volume indoor blowers. The sum of the individual “on” indoor blowers' air volume rates is the heating full-load air volume rate for the system.
3.1.4.6 Heating Intermediate Air Volume RateIdentify the certified heating intermediate air volume rate and certified instructions for setting fan speed or controls. If there is no certified heating intermediate air volume rate, use the final indoor blower control settings as determined when setting the heating full-load air volume rate, and readjust the exhaust fan of the airflow measuring apparatus if necessary to reset to the cooling full-load air volume obtained in section 3.1.4.2 of this appendix. Calculate the target minimum external static pressure as described in section 3.1.4.2 of this appendix.
a. For ducted blower coil system heat pumps that do not have a constant-air-volume indoor blower, adjust for external static pressure as described in section 3.1.4.2.a of this appendix for cooling minimum air volume rate.
b. For ducted heat pumps tested with constant-air-volume indoor blowers installed, conduct the H2V Test at an external static pressure that does not cause an automatic shutdown of the indoor blower or air volume rate variation QVar, defined in section 3.1.4.1.1.b of this appendix, greater than 10 percent, while being as close to, but not less than the target minimum external static pressure. Additional test steps as described in section 3.9.1.c of this appendix are required if the measured external static pressure exceeds the target value by more than 0.03 inches of water.
c. For non-ducted heat pumps, the heating intermediate air volume rate is the air volume rate that results when the heat pump operates at an external static pressure of zero inches of water and at the fan speed selected by the controls of the unit for the H2V Test conditions.
3.1.4.7 Heating Nominal Air Volume RateThe manufacturer must specify the heating nominal air volume rate and the instructions for setting fan speed or controls. Calculate target minimum external static pressure as described in section 3.1.4.2 of this appendix. Make adjustments as described in section 3.14.6 of this appendix for heating intermediate air volume rate so that the target minimum external static pressure is met or exceeded.
3.1.5 Indoor Test Room Requirement When the Air Surrounding the Indoor Unit is Not Supplied From the Same Source as the Air Entering the Indoor UnitIf using a test set-up where air is ducted directly from the air reconditioning apparatus to the indoor coil inlet (see Figure 2, Loop Air-Enthalpy Test Method Arrangement, of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3)), maintain the dry bulb temperature within the test room within ±5.0 °F of the applicable sections 3.2 and 3.6 dry bulb temperature test condition for the air entering the indoor unit. Dew point must be within 2 °F of the required inlet conditions.
3.1.6 Air Volume Rate CalculationsFor all steady-state tests and for frost accumulation (H2, H21, H22, H2V) tests, calculate the air volume rate through the indoor coil as specified in sections 7.7.2.1 and 7.7.2.2 of ANSI/ASHRAE 37-2009. When using the outdoor air enthalpy method, follow sections 7.7.2.1 and 7.7.2.2 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3) to calculate the air volume rate through the outdoor coil. To express air volume rates in terms of standard air, use:
Where: V
s = air volume rate of standard (dry) air, (ft 3/min)da V mx = air
volume rate of the air-water vapor mixture, (ft 3/min)mx vn′ =
specific volume of air-water vapor mixture at the nozzle, ft 3 per
lbm of the air-water vapor mixture Wn = humidity ratio at the
nozzle, lbm of water vapor per lbm of dry air 0.075 = the density
associated with standard (dry) air, (lbm/ft 3) vn = specific volume
of the dry air portion of the mixture evaluated at the dry-bulb
temperature, vapor content, and barometric pressure existing at the
nozzle, ft 3 per lbm of dry air. Note:
In the first printing of ANSI/ASHRAE 37-2009, the second IP equation for Qmi should read,
3.1.7
Test Sequence
Before making test measurements used to calculate performance, operate the equipment for the “break-in” period specified in the certification report, which may not exceed 20 hours. Each compressor of the unit must undergo this “break-in” period. When testing a ducted unit (except if a heating-only heat pump), conduct the A or A2 Test first to establish the cooling full-load air volume rate. For ducted heat pumps where the heating and cooling full-load air volume rates are different, make the first heating mode test one that requires the heating full-load air volume rate. For ducted heating-only heat pumps, conduct the H1 or H12 Test first to establish the heating full-load air volume rate. When conducting a cyclic test, always conduct it immediately after the steady-state test that requires the same test conditions. For variable-speed systems, the first test using the cooling minimum air volume rate should precede the EV Test, and the first test using the heating minimum air volume rate must precede the H2V Test. The test laboratory makes all other decisions on the test sequence.
3.1.8 Requirement for the Air Temperature Distribution Leaving the Indoor CoilFor at least the first cooling mode test and the first heating mode test, monitor the temperature distribution of the air leaving the indoor coil using the grid of individual sensors described in sections 2.5 and 2.5.4 of this appendix. For the 30-minute data collection interval used to determine capacity, the maximum spread among the outlet dry bulb temperatures from any data sampling must not exceed 1.5 °F. Install the mixing devices described in section 2.5.4.2 of this appendix to minimize the temperature spread.
3.1.9 Requirement for the Air Temperature Distribution Entering the Outdoor CoilMonitor the Temperatures of the Air Entering the Outdoor Coil Using Air Sampling Devices and/or Temperature Sensor Grids, Maintaining the Required Tolerances, if Applicable, as Described in section 2.11 of this appendix
3.1.10 Control of Auxiliary Resistive Heating ElementsExcept as noted, disable heat pump resistance elements used for heating indoor air at all times, including during defrost cycles and if they are normally regulated by a heat comfort controller. For heat pumps equipped with a heat comfort controller, enable the heat pump resistance elements only during the below-described, short test. For single-speed heat pumps covered under section 3.6.1 of this appendix, the short test follows the H1 or, if conducted, the H1C Test. For two-capacity heat pumps and heat pumps covered under section 3.6.2 of this appendix, the short test follows the H12 Test. Set the heat comfort controller to provide the maximum supply air temperature. With the heat pump operating and while maintaining the heating full-load air volume rate, measure the temperature of the air leaving the indoor-side beginning 5 minutes after activating the heat comfort controller. Sample the outlet dry-bulb temperature at regular intervals that span 5 minutes or less. Collect data for 10 minutes, obtaining at least 3 samples. Calculate the average outlet temperature over the 10-minute interval, TCC.
3.2 Cooling Mode Tests for Different Types of Air Conditioners and Heat Pumps 3.2.1 Tests for a System Having a Single-Speed Compressor and Fixed Cooling Air Volume RateThis set of tests is for single-speed-compressor units that do not have a cooling minimum air volume rate or a cooling intermediate air volume rate that is different than the cooling full load air volume rate. Conduct two steady-state wet coil tests, the A and B Tests. Use the two optional dry-coil tests, the steady-state C Test and the cyclic D Test, to determine the cooling mode cyclic degradation coefficient, CD c. If the two optional tests are conducted but yield a tested CD c that exceeds the default CD c or if the two optional tests are not conducted, assign CD c the default value of 0.25 (for outdoor units with no match) or 0.2 (for all other systems). Table 5 specifies test conditions for these four tests.
Table 5 - Cooling Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed Cooling Air Volume Rate
| Test description | Air entering
indoor unit temperature ( °F) |
Air entering
outdoor unit temperature ( °F) |
Cooling air volume rate | ||
|---|---|---|---|---|---|
| Dry bulb | Wet bulb | Dry bulb | Wet bulb | ||
| A Test - required (steady, wet coil) | 80 | 67 | 95 | 1 75 | Cooling full-load 2. |
| B Test - required (steady, wet coil) | 80 | 67 | 82 | 1 65 | Cooling full-load 2. |
| C Test - optional (steady, dry coil) | 80 | ( 3) | 82 | Cooling full-load 2. | |
| D Test - optional (cyclic, dry coil) | 80 | ( 3) | 82 | ( 4). | |
1 The specified test condition only applies if the unit rejects condensate to the outdoor coil.
2 Defined in section 3.1.4.1 of this appendix.
3 The entering air must have a low enough moisture content so no condensate forms on the indoor coil. (It is recommended that an indoor wet-bulb temperature of 57 °F or less be used.)
4 Maintain the airflow nozzles static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity pressure as measured during the C Test.
Conduct four steady-state wet coil tests: The A2, A1, B2, and B1 tests. Use the two optional dry-coil tests, the steady-state C1 test and the cyclic D1 test, to determine the cooling mode cyclic degradation coefficient, CD c. If the two optional tests are conducted but yield a tested CD c that exceeds the default CD c or if the two optional tests are not conducted, assign CD c the default value of 0.2.
3.2.2.2 Indoor Blower Capacity Modulation Based on Adjusting the Sensible to Total (S/T) Cooling Capacity RatioThe testing requirements are the same as specified in section 3.2.1 of this appendix and Table 5. Use a cooling full-load air volume rate that represents a normal installation. If performed, conduct the steady-state C Test and the cyclic D Test with the unit operating in the same S/T capacity control mode as used for the B Test.
Table 6 - Cooling Mode Test Conditions for Units With a Single-Speed Compressor That Meet the Section 3.2.2.1 Indoor Unit Requirements
| Test description | Air entering
indoor unit temperature ( °F) |
Air entering
outdoor unit temperature ( °F) |
Cooling air volume rate | ||
|---|---|---|---|---|---|
| Dry bulb | Wet bulb | Dry bulb | Wet bulb | ||
| A2 Test - required (steady, wet coil) | 80 | 67 | 95 | 1 75 | Cooling full-load 2. |
| A1 Test - required (steady, wet coil) | 80 | 67 | 95 | 1 75 | Cooling minimum 3. |
| B2 Test - required (steady, wet coil) | 80 | 67 | 82 | 1 65 | Cooling full-load 2. |
| B1 Test - required (steady, wet coil) | 80 | 67 | 82 | 1 65 | Cooling minimum 3. |
| C1 Test 4 - optional (steady, dry coil) | 80 | ( 4) | 82 | Cooling minimum 3. | |
| D1 Test 4 - optional (cyclic, dry coil) | 80 | ( 4) | 82 | ( 5). | |
1 The specified test condition only applies if the unit rejects condensate to the outdoor coil.
2 Defined in section 3.1.4.1 of this appendix.
3 Defined in section 3.1.4.2 of this appendix.
4 The entering air must have a low enough moisture content so no condensate forms on the indoor coil. (It is recommended that an indoor wet-bulb temperature of 57 °F or less be used.)
5 Maintain the airflow nozzles static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity pressure as measured during the C1 Test.
a. Conduct four steady-state wet coil tests: the A2, B2, B1, and F1 Tests. Use the two optional dry-coil tests, the steady-state C1 Test and the cyclic D1 Test, to determine the cooling-mode cyclic-degradation coefficient, CD c. If the two optional tests are conducted but yield a tested CD c that exceeds the default CD c or if the two optional tests are not conducted, assign CD c the default value of 0.2. Table 7 specifies test conditions for these six tests.
b. For units having a variable-speed indoor blower that is modulated to adjust the sensible to total (S/T) cooling capacity ratio, use cooling full-load and cooling minimum air volume rates that represent a normal installation. Additionally, if conducting the dry-coil tests, operate the unit in the same S/T capacity control mode as used for the B1 Test.
c. Test two-capacity, northern heat pumps (see section 1.2 of this appendix, Definitions) in the same way as a single speed heat pump with the unit operating exclusively at low compressor capacity (see section 3.2.1 of this appendix and Table 5).
d. If a two-capacity air conditioner or heat pump locks out low-capacity operation at higher outdoor temperatures, then use the two dry-coil tests, the steady-state C2 Test and the cyclic D2 Test, to determine the cooling-mode cyclic-degradation coefficient that only applies to on/off cycling from high capacity, CD c(k=2). If the two optional tests are conducted but yield a tested CD c(k = 2) that exceeds the default CD c(k = 2) or if the two optional tests are not conducted, assign CD c(k = 2) the default value. The default CD c(k=2) is the same value as determined or assigned for the low-capacity cyclic-degradation coefficient, CD c [or equivalently, CD c(k=1)].
Table 7 - Cooling Mode Test Conditions for Units Having a Two-Capacity Compressor
| Test description | Air entering
indoor unit temperature ( °F) |
Air entering
outdoor unit temperature ( °F) |
Compressor capacity | Cooling air volume rate | ||
|---|---|---|---|---|---|---|
| Dry bulb | Wet bulb | Dry bulb | Wet bulb | |||
| A2 Test - required (steady, wet coil) | 80 | 67 | 95 | 1 75 | High | Cooling Full-Load. 2 |
| B2 Test - required (steady, wet coil) | 80 | 67 | 82 | 1 65 | High | Cooling Full-Load. 2 |
| B1 Test - required (steady, wet coil) | 80 | 67 | 82 | 1 65 | Low | Cooling Minimum. 3 |
| C2 Test - optional (steady, dry-coil) | 80 | ( 4) | 82 | High | Cooling Full-Load. 2 | |
| D2 Test - optional (cyclic, dry-coil) | 80 | ( 4) | 82 | High | ( 5). | |
| C1 Test - optional (steady, dry-coil) | 80 | ( 4) | 82 | Low | Cooling Minimum. 3 | |
| D1 Test - optional (cyclic, dry-coil) | 80 | ( 4) | 82 | Low | ( 6). | |
| F1 Test - required (steady, wet coil) | 80 | 67 | 67 | 1 53.5 | Low | Cooling Minimum. 3 |
1 The specified test condition only applies if the unit rejects condensate to the outdoor coil.
2 Defined in section 3.1.4.1 of this appendix.
3 Defined in section 3.1.4.2 of this appendix.
4 The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE recommends using an indoor air wet-bulb temperature of 57 °F or less.
5 Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured during the C2 Test.
6 Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured during the C1 Test.
a. Conduct five steady-state wet coil tests: The A2, EV, B2, B1, and F1 Tests. Use the two optional dry-coil tests, the steady-state G1 Test and the cyclic I1 Test, to determine the cooling mode cyclic degradation coefficient, CD c. If the two optional tests are conducted but yield a tested CD c that exceeds the default CD c or if the two optional tests are not conducted, assign CD c the default value of 0.25. Table 8 specifies test conditions for these seven tests. The compressor shall operate at the same cooling full speed, measured by RPM or power input frequency (Hz), for both the A2 and B2 tests. The compressor shall operate at the same cooling minimum speed, measured by RPM or power input frequency (Hz), for the B1, F1, G1, and I1 tests. Determine the cooling intermediate compressor speed cited in Table 8 using:
where a
tolerance of plus 5 percent or the next higher inverter frequency
step from that calculated is allowed.
b. For units that modulate the indoor blower speed to adjust the sensible to total (S/T) cooling capacity ratio, use cooling full-load, cooling intermediate, and cooling minimum air volume rates that represent a normal installation. Additionally, if conducting the dry-coil tests, operate the unit in the same S/T capacity control mode as used for the F1 Test.
c. For multiple-split air conditioners and heat pumps (except where noted), the following procedures supersede the above requirements: For all Table 8 tests specified for a minimum compressor speed, turn off at least one indoor unit. The manufacturer shall designate the particular indoor unit(s) that is turned off. The manufacturer must also specify the compressor speed used for the Table 8 EV Test, a cooling-mode intermediate compressor speed that falls within 1/4 and 3/4 of the difference between the full and minimum cooling-mode speeds. The manufacturer should prescribe an intermediate speed that is expected to yield the highest EER for the given EV Test conditions and bracketed compressor speed range. The manufacturer can designate that one or more indoor units are turned off for the EV Test.
Table 8 - Cooling Mode Test Condition for Units Having a Variable-Speed Compressor
| Test description | Air entering
indoor unit temperature ( °F) |
Air entering
outdoor unit temperature ( °F) |
Compressor speed | Cooling air volume rate | ||
|---|---|---|---|---|---|---|
| Dry bulb | Wet bulb | Dry bulb | Wet bulb | |||
| A2 Test - required (steady, wet coil) | 80 | 67 | 95 | 1 75 | Cooling Full | Cooling Full-Load. 2 |
| B2 Test - required (steady, wet coil) | 80 | 67 | 82 | 1 65 | Cooling Full | Cooling Full-Load. 2 |
| EV Test - required (steady, wet coil) | 80 | 67 | 87 | 1 69 | Cooling Intermediate | Cooling Intermediate. 3 |
| B1 Test - required (steady, wet coil) | 80 | 67 | 82 | 1 65 | Cooling Minimum | Cooling Minimum. 4 |
| F1 Test - required (steady, wet coil) | 80 | 67 | 67 | 1 53.5 | Cooling Minimum | Cooling Minimum. 4 |
| G1 Test 5 - optional (steady, dry-coil) | 80 | ( 6) | 67 | Cooling Minimum | Cooling Minimum. 4 | |
| I1 Tes t 5 - optional (cyclic, dry-coil) | 80 | ( 6) | 67 | Cooling Minimum | ( 6). | |
1 The specified test condition only applies if the unit rejects condensate to the outdoor coil.
2 Defined in section 3.1.4.1 of this appendix.
3 Defined in section 3.1.4.3 of this appendix.
4 Defined in section 3.1.4.2 of this appendix.
5 The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE recommends using an indoor air wet bulb temperature of 57 °F or less.
6 Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity pressure as measured during the G1 Test.
Test triple-capacity, northern heat pumps for the cooling mode in the same way as specified in section 3.2.3 of this appendix for units having a two-capacity compressor.
3.2.6 Tests for an Air Conditioner or Heat Pump Having a Single Indoor Unit Having Multiple Indoor Blowers and Offering Two Stages of Compressor ModulationConduct the cooling mode tests specified in section 3.2.3 of this appendix.
3.3 Test Procedures for Steady-State Wet Coil Cooling Mode Tests (the A, A2, A1, B, B2, B1, EV, and F1 Tests)a. For the pretest interval, operate the test room reconditioning apparatus and the unit to be tested until maintaining equilibrium conditions for at least 30 minutes at the specified section 3.2 test conditions. Use the exhaust fan of the airflow measuring apparatus and, if installed, the indoor blower of the test unit to obtain and then maintain the indoor air volume rate and/or external static pressure specified for the particular test. Continuously record (see section 1.2 of this appendix, Definitions):
(1) The dry-bulb temperature of the air entering the indoor coil,
(2) The water vapor content of the air entering the indoor coil,
(3) The dry-bulb temperature of the air entering the outdoor coil, and
(4) For the section 2.2.4 of this appendix cases where its control is required, the water vapor content of the air entering the outdoor coil.
Refer to section 3.11 of this appendix for additional requirements that depend on the selected secondary test method.
b. After satisfying the pretest equilibrium requirements, make the measurements specified in Table 3 of ANSI/ASHRAE 37-2009 for the indoor air enthalpy method and the user-selected secondary method. Make said Table 3 measurements at equal intervals that span 5 minutes or less. Continue data sampling until reaching a 30-minute period (e.g., seven consecutive 5-minute samples) where the test tolerances specified in Table 9 are satisfied. For those continuously recorded parameters, use the entire data set from the 30-minute interval to evaluate Table 9 compliance. Determine the average electrical power consumption of the air conditioner or heat pump over the same 30-minute interval.
c. Calculate indoor-side total cooling capacity and sensible cooling capacity as specified in sections 7.3.3.1 and 7.3.3.3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3). To calculate capacity, use the averages of the measurements (e.g. inlet and outlet dry bulb and wet bulb temperatures measured at the psychrometers) that are continuously recorded for the same 30-minute interval used as described above to evaluate compliance with test tolerances. Do not adjust the parameters used in calculating capacity for the permitted variations in test conditions. Evaluate air enthalpies based on the measured barometric pressure. Use the values of the specific heat of air given in section 7.3.3.1 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3) for calculation of the sensible cooling capacities. Assign the average total space cooling capacity, average sensible cooling capacity, and electrical power consumption over the 30-minute data collection interval to the variables Q c k(T), Q sc k(T) and E c k(T), respectively. For these three variables, replace the “T” with the nominal outdoor temperature at which the test was conducted. The superscript k is used only when testing multi-capacity units. Use the superscript k=2 to denote a test with the unit operating at high capacity or full speed, k=1 to denote low capacity or minimum speed, and k=v to denote the intermediate speed.
d. For mobile home and space-constrained ducted coil-only system tests, decrease Q c k(T) by
where V s
is the average measured indoor air volume rate expressed in units
of cubic feet per minute of standard air (scfm).
For non-mobile, non-space-constrained home ducted coil-only system tests, decrease Q c k(T) by
where V s
is the average measured indoor air volume rate expressed in units
of cubic feet per minute of standard air (scfm).
Table 9 - Test Operating and Test Condition Tolerances for Section 3.3 Steady-State Wet Coil Cooling Mode Tests and Section 3.4 Dry Coil Cooling Mode Tests
| Test operating tolerance 1 |
Test condition tolerance 1 |
|
|---|---|---|
| Indoor dry-bulb, °F | ||
| Entering temperature | 2.0 | 0.5 |
| Leaving temperature | 2.0 | |
| Indoor wet-bulb, °F | ||
| Entering temperature | 1.0 | 2 0.3 |
| Leaving temperature | 2 1.0 | |
| Outdoor dry-bulb, °F | ||
| Entering temperature | 2.0 | 0.5 |
| Leaving temperature | 3 2.0 | |
| Outdoor wet-bulb, °F | ||
| Entering temperature | 1.0 | 4 0.3 |
| Leaving temperature | 3 1.0 | |
| External resistance to airflow, inches of water | 0.05 | 5 0.02 |
| Electrical voltage, % of reading. | 2.0 | 1.5 |
| Nozzle pressure drop, % of reading. | 2.0 |
1 See section 1.2 of this appendix, Definitions.
2 Only applies during wet coil tests; does not apply during steady-state, dry coil cooling mode tests.
3 Only applies when using the outdoor air enthalpy method.
4 Only applies during wet coil cooling mode tests where the unit rejects condensate to the outdoor coil.
5 Only applies when testing non-ducted units.
e. For air conditioners and heat pumps having a constant-air-volume-rate indoor blower, the five additional steps listed below are required if the average of the measured external static pressures exceeds the applicable sections 3.1.4 minimum (or target) external static pressure (ΔPmin) by 0.03 inches of water or more.
(1) Measure the average power consumption of the indoor blower motor (E fan,1) and record the corresponding external static pressure (ΔP1) during or immediately following the 30-minute interval used for determining capacity.
(2) After completing the 30-minute interval and while maintaining the same test conditions, adjust the exhaust fan of the airflow measuring apparatus until the external static pressure increases to approximately ΔP1 + (ΔP1 − ΔPmin).
(3) After re-establishing steady readings of the fan motor power and external static pressure, determine average values for the indoor blower power (E fan,2) and the external static pressure (ΔP2) by making measurements over a 5-minute interval.
(4) Approximate the average power consumption of the indoor blower motor at ΔPmin using linear extrapolation:
(5) Increase the total space cooling capacity, Q c k(T), by the quantity (E fan,1 − E fan,min), when expressed on a Btu/h basis. Decrease the total electrical power, E c k(T), by the same fan power difference, now expressed in watts.
3.4 Test Procedures for the Steady-State Dry-Coil Cooling-Mode Tests (the C, C1, C2, and G1 Tests)a. Except for the modifications noted in this section, conduct the steady-state dry coil cooling mode tests as specified in section 3.3 of this appendix for wet coil tests. Prior to recording data during the steady-state dry coil test, operate the unit at least one hour after achieving dry coil conditions. Drain the drain pan and plug the drain opening. Thereafter, the drain pan should remain completely dry.
b. Denote the resulting total space cooling capacity and electrical power derived from the test as Q ss,dry and E ss,dry. With regard to a section 3.3 deviation, do not adjust Q ss,dry for duct losses (i.e., do not apply section 7.3.3.3 of ANSI/ASHRAE 37-2009). In preparing for the section 3.5 cyclic tests of this appendix, record the average indoor-side air volume rate, V , specific heat of the air, Cp,a (expressed on dry air basis), specific volume of the air at the nozzles, v′n, humidity ratio at the nozzles, Wn, and either pressure difference or velocity pressure for the flow nozzles. For units having a variable-speed indoor blower (that provides either a constant or variable air volume rate) that will or may be tested during the cyclic dry coil cooling mode test with the indoor blower turned off (see section 3.5 of this appendix), include the electrical power used by the indoor blower motor among the recorded parameters from the 30-minute test.
c. If the temperature sensors used to provide the primary measurement of the indoor-side dry bulb temperature difference during the steady-state dry-coil test and the subsequent cyclic dry-coil test are different, include measurements of the latter sensors among the regularly sampled data. Beginning at the start of the 30-minute data collection period, measure and compute the indoor-side air dry-bulb temperature difference using both sets of instrumentation, ΔT (Set SS) and ΔT (Set CYC), for each equally spaced data sample. If using a consistent data sampling rate that is less than 1 minute, calculate and record minutely averages for the two temperature differences. If using a consistent sampling rate of one minute or more, calculate and record the two temperature differences from each data sample. After having recorded the seventh (i=7) set of temperature differences, calculate the following ratio using the first seven sets of values:
Each time
a subsequent set of temperature differences is recorded (if
sampling more frequently than every 5 minutes), calculate
FCD using the most recent seven sets of values. Continue
these calculations until the 30-minute period is completed or until
a value for FCD is calculated that falls outside the
allowable range of 0.94-1.06. If the latter occurs, immediately
suspend the test and identify the cause for the disparity in the
two temperature difference measurements. Recalibration of one or
both sets of instrumentation may be required. If all the values for
FCD are within the allowable range, save the final value of
the ratio from the 30-minute test as FCD*. If the
temperature sensors used to provide the primary measurement of the
indoor-side dry bulb temperature difference during the steady-state
dry-coil test and the subsequent cyclic dry-coil test are the same,
set FCD*= 1. 3.5 Test Procedures for the Cyclic Dry-Coil
Cooling-Mode Tests (the D, D1, D2, and I1 Tests)
After completing the steady-state dry-coil test, remove the outdoor air enthalpy method test apparatus, if connected, and begin manual OFF/ON cycling of the unit's compressor. The test set-up should otherwise be identical to the set-up used during the steady-state dry coil test. When testing heat pumps, leave the reversing valve during the compressor OFF cycles in the same position as used for the compressor ON cycles, unless automatically changed by the controls of the unit. For units having a variable-speed indoor blower, the manufacturer has the option of electing at the outset whether to conduct the cyclic test with the indoor blower enabled or disabled. Always revert to testing with the indoor blower disabled if cyclic testing with the fan enabled is unsuccessful.
a. For all cyclic tests, the measured capacity must be adjusted for the thermal mass stored in devices and connections located between measured points. Follow the procedure outlined in section 7.4.3.4.5 of ASHRAE 116-2010 (incorporated by reference, see § 430.3) to ensure any required measurements are taken.
b. For units having a single-speed or two-capacity compressor, cycle the compressor OFF for 24 minutes and then ON for 6 minutes (Δτcyc,dry = 0.5 hours). For units having a variable-speed compressor, cycle the compressor OFF for 48 minutes and then ON for 12 minutes (Δτcyc,dry = 1.0 hours). Repeat the OFF/ON compressor cycling pattern until the test is completed. Allow the controls of the unit to regulate cycling of the outdoor fan. If an upturned duct is used, measure the dry-bulb temperature at the inlet of the device at least once every minute and ensure that its test operating tolerance is within 1.0 °F for each compressor OFF period.
c. Sections 3.5.1 and 3.5.2 of this appendix specify airflow requirements through the indoor coil of ducted and non-ducted indoor units, respectively. In all cases, use the exhaust fan of the airflow measuring apparatus (covered under section 2.6 of this appendix) along with the indoor blower of the unit, if installed and operating, to approximate a step response in the indoor coil airflow. Regulate the exhaust fan to quickly obtain and then maintain the flow nozzle static pressure difference or velocity pressure at the same value as was measured during the steady-state dry coil test. The pressure difference or velocity pressure should be within 2 percent of the value from the steady-state dry coil test within 15 seconds after airflow initiation. For units having a variable-speed indoor blower that ramps when cycling on and/or off, use the exhaust fan of the airflow measuring apparatus to impose a step response that begins at the initiation of ramp up and ends at the termination of ramp down.
d. For units having a variable-speed indoor blower, conduct the cyclic dry coil test using the pull-thru approach described below if any of the following occur when testing with the fan operating:
(1) The test unit automatically cycles off;
(2) Its blower motor reverses; or
(3) The unit operates for more than 30 seconds at an external static pressure that is 0.1 inches of water or more higher than the value measured during the prior steady-state test.
For the pull-thru approach, disable the indoor blower and use the exhaust fan of the airflow measuring apparatus to generate the specified flow nozzles static pressure difference or velocity pressure. If the exhaust fan cannot deliver the required pressure difference because of resistance created by the unpowered indoor blower, temporarily remove the indoor blower.
e. Conduct three complete compressor OFF/ON cycles with the test tolerances given in Table 10 satisfied. Calculate the degradation coefficient CD for each complete cycle. If all three CD values are within 0.02 of the average CD then stability has been achieved, use the highest CD value of these three. If stability has not been achieved, conduct additional cycles, up to a maximum of eight cycles, until stability has been achieved between three consecutive cycles. Once stability has been achieved, use the highest CD value of the three consecutive cycles that establish stability. If stability has not been achieved after eight cycles, use the highest CD from cycle one through cycle eight, or the default CD, whichever is lower.
f. With regard to the Table 10 parameters, continuously record the dry-bulb temperature of the air entering the indoor and outdoor coils during periods when air flows through the respective coils. Sample the water vapor content of the indoor coil inlet air at least every 2 minutes during periods when air flows through the coil. Record external static pressure and the air volume rate indicator (either nozzle pressure difference or velocity pressure) at least every minute during the interval that air flows through the indoor coil. (These regular measurements of the airflow rate indicator are in addition to the required measurement at 15 seconds after flow initiation.) Sample the electrical voltage at least every 2 minutes beginning 30 seconds after compressor start-up. Continue until the compressor, the outdoor fan, and the indoor blower (if it is installed and operating) cycle off.
g. For ducted units, continuously record the dry-bulb temperature of the air entering (as noted above) and leaving the indoor coil. Or if using a thermopile, continuously record the difference between these two temperatures during the interval that air flows through the indoor coil. For non-ducted units, make the same dry-bulb temperature measurements beginning when the compressor cycles on and ending when indoor coil airflow ceases.
h. Integrate the electrical power over complete cycles of length Δτcyc,dry. For ducted blower coil systems tested with the unit's indoor blower operating for the cycling test, integrate electrical power from indoor blower OFF to indoor blower OFF. For all other ducted units and for non-ducted units, integrate electrical power from compressor OFF to compressor OFF. (Some cyclic tests will use the same data collection intervals to determine the electrical energy and the total space cooling. For other units, terminate data collection used to determine the electrical energy before terminating data collection used to determine total space cooling.)
Table 10 - Test Operating and Test Condition Tolerances for Cyclic Dry Coil Cooling Mode Tests
| Test operating tolerance 1 | Test condition tolerance 1 | |
|---|---|---|
| Indoor entering dry-bulb temperature, 2 °F | 2.0 | 0.5 |
| Indoor entering wet-bulb temperature, °F | ( 3) | |
| Outdoor entering dry-bulb temperature, 2 °F | 2.0 | 0.5 |
| External resistance to airflow, 2 inches of water | 0.05 | |
| Airflow nozzle pressure difference or velocity pressure, 2% of reading | 2.0 | 4 2.0 |
| Electrical voltage, 5 % of reading | 2.0 | 1.5 |
1 See section 1.2 of this appendix, Definitions.
2 Applies during the interval that air flows through the indoor (outdoor) coil except for the first 30 seconds after flow initiation. For units having a variable-speed indoor blower that ramps, the tolerances listed for the external resistance to airflow apply from 30 seconds after achieving full speed until ramp down begins.
3 Shall at no time exceed a wet-bulb temperature that results in condensate forming on the indoor coil.
4 The test condition must be the average nozzle pressure difference or velocity pressure measured during the steady-state dry coil test.
5 Applies during the interval when at least one of the following - the compressor, the outdoor fan, or, if applicable, the indoor blower - are operating except for the first 30 seconds after compressor start-up.
If the Table 10 tolerances are satisfied over the complete cycle, record the measured electrical energy consumption as ecyc,dry and express it in units of watt-hours. Calculate the total space cooling delivered, qcyc,dry, in units of Btu using,
Where,
V , Cp,a, vn′ (or vn), Wn, and FCD* are the values
recorded during the section 3.4 dry coil steady-state test and
Tal(τ) = dry bulb temperature of the air entering the indoor coil
at time τ, °F. Ta2(τ) = dry bulb temperature of the air leaving the
indoor coil at time τ, °F. τ1 = for ducted units, the elapsed time
when airflow is initiated through the indoor coil; for non-ducted
units, the elapsed time when the compressor is cycled on, hr. τ2 =
the elapsed time when indoor coil airflow ceases, hr.
Adjust the total space cooling delivered, qcyc,dry, according to calculation method outlined in section 7.4.3.4.5 of ASHRAE 116-2010 (incorporated by reference, see § 430.3).
3.5.1 Procedures When Testing Ducted SystemsThe automatic controls that are installed in the test unit must govern the OFF/ON cycling of the air moving equipment on the indoor side (exhaust fan of the airflow measuring apparatus and the indoor blower of the test unit). For ducted coil-only systems rated based on using a fan time-delay relay, control the indoor coil airflow according to the OFF delay listed by the manufacturer in the certification report. For ducted units having a variable-speed indoor blower that has been disabled (and possibly removed), start and stop the indoor airflow at the same instances as if the fan were enabled. For all other ducted coil-only systems, cycle the indoor coil airflow in unison with the cycling of the compressor. If air damper boxes are used, close them on the inlet and outlet side during the OFF period. Airflow through the indoor coil should stop within 3 seconds after the automatic controls of the test unit (act to) de-energize the indoor blower. For mobile home and space-constrained ducted coil-only systems increase ecyc,dry by the quantity,
where V s
is the average indoor air volume rate from the section 3.4 dry coil
steady-state test and is expressed in units of cubic feet per
minute of standard air (scfm). For ducted non-mobile,
non-space-constrained home coil-only units increase ecyc,dry by the
quantity, 
where
V s is the average indoor air volume rate from the section
3.4 dry coil steady-state test and is expressed in units of cubic
feet per minute of standard air (scfm). For units having a
variable-speed indoor blower that is disabled during the cyclic
test, increase ecyc,dry and decrease qcyc,dry based on:
a. The product of [τ2 − τ 1] and the indoor blower power measured during or following the dry coil steady-state test; or,
b. The following algorithm if the indoor blower ramps its speed when cycling.
(1) Measure the electrical power consumed by the variable-speed indoor blower at a minimum of three operating conditions: at the speed/air volume rate/external static pressure that was measured during the steady-state test, at operating conditions associated with the midpoint of the ramp-up interval, and at conditions associated with the midpoint of the ramp-down interval. For these measurements, the tolerances on the airflow volume or the external static pressure are the same as required for the section 3.4 steady-state test.
(2) For each case, determine the fan power from measurements made over a minimum of 5 minutes.
(3) Approximate the electrical energy consumption of the indoor blower if it had operated during the cyclic test using all three power measurements. Assume a linear profile during the ramp intervals. The manufacturer must provide the durations of the ramp-up and ramp-down intervals. If the test setup instructions included with the unit by the manufacturer specifies a ramp interval that exceeds 45 seconds, use a 45-second ramp interval nonetheless when estimating the fan energy.
3.5.2 Procedures When Testing Non-Ducted Indoor UnitsDo not use airflow prevention devices when conducting cyclic tests on non-ducted indoor units. Until the last OFF/ON compressor cycle, airflow through the indoor coil must cycle off and on in unison with the compressor. For the last OFF/ON compressor cycle - the one used to determine ecyc,dry and qcyc,dry - use the exhaust fan of the airflow measuring apparatus and the indoor blower of the test unit to have indoor airflow start 3 minutes prior to compressor cut-on and end three minutes after compressor cutoff. Subtract the electrical energy used by the indoor blower during the 3 minutes prior to compressor cut-on from the integrated electrical energy, ecyc,dry. Add the electrical energy used by the indoor blower during the 3 minutes after compressor cutoff to the integrated cooling capacity, qcyc,dry. For the case where the non-ducted indoor unit uses a variable-speed indoor blower which is disabled during the cyclic test, correct ecyc,dry and qcyc,dry using the same approach as prescribed in section 3.5.1 of this appendix for ducted units having a disabled variable-speed indoor blower.
3.5.3 Cooling-Mode Cyclic-Degradation Coefficient CalculationUse the two dry-coil tests to determine the cooling-mode cyclic-degradation coefficient, CD c. Append “(k=2)” to the coefficient if it corresponds to a two-capacity unit cycling at high capacity. If the two optional tests are conducted but yield a tested CD c that exceeds the default CD c or if the two optional tests are not conducted, assign CD c the default value of 0.25 for variable-speed compressor systems and outdoor units with no match, and 0.20 for all other systems. The default value for two-capacity units cycling at high capacity, however, is the low-capacity coefficient, i.e., CD c(k=2) = CD c. Evaluate CD c using the above results and those from the section 3.4 dry-coil steady-state test.
Where:
the
average energy efficiency ratio during the cyclic dry coil cooling
mode test, Btu/W·h 
the average energy
efficiency ratio during the steady-state dry coil cooling mode
test, Btu/W·h 
the cooling load
factor dimensionless
Round the calculated value for CD c to the nearest 0.01. If CD c is negative, then set it equal to zero.
3.6 Heating Mode Tests for Different Types of Heat Pumps, Including Heating-Only Heat Pumps 3.6.1 Tests for a Heat Pump Having a Single-Speed Compressor and Fixed Heating Air Volume RateThis set of tests is for single-speed-compressor heat pumps that do not have a heating minimum air volume rate or a heating intermediate air volume rate that is different than the heating full load air volume rate. Conducting a very low temperature test (H4) is optional. Conduct the optional high temperature cyclic (H1C) test to determine the heating mode cyclic-degradation coefficient, CD h. If this optional test is conducted but yields a tested CD h that exceeds the default CD h or if the optional test is not conducted, assign CD h the default value of 0.25. Test conditions for the five tests are specified in Table 11 of this section.
Table 11 - Heating Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed-Speed Indoor Blower, a Constant Air Volume Rate Indoor Blower, or Coil-Only
| Test description | Air entering
indoor unit temperature ( °F) |
Air entering
outdoor unit temperature ( °F) |
Heating air volume rate | ||
|---|---|---|---|---|---|
| Dry bulb | Wet bulb | Dry bulb | Wet bulb | ||
| H1 Test (required, steady) | 70 | 60 (max) | 47 | 43 | Heating Full-load. 1 |
| H1C Test (optional, cyclic) | 70 | 60 (max) | 47 | 43 | ( 2). |
| H2 Test (required) | 70 | 60 (max) | 35 | 33 | Heating Full-load. 1 |
| H3 Test (required, steady) | 70 | 60 (max) | 17 | 15 | Heating Full-load. 1 |
| H4 Test (optional, steady) | 70 | 60 (max) | 5 | 3 (max) | Heating Full-load. 1 |
1 Defined in section 3.1.4.4 of this appendix.
2 Maintain the airflow nozzles static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity pressure as measured during the H1 Test.
Conduct five tests: Two high temperature tests (H12 and H11), one frost accumulation test (H22), and two low temperature tests (H32 and H31). Conducting an additional frost accumulation test (H21) and a very low temperature test (H42) is optional. Conduct the optional high temperature cyclic (H1C1) test to determine the heating mode cyclic-degradation coefficient, CD h. If this optional test is conducted but yields a tested CD h that exceeds the default CD h or if the optional test is not conducted, assign CD h the default value of 0.25. Test conditions for the seven tests are specified in Table 12. If the optional H21 test is not performed, use the following equations to approximate the capacity and electrical power of the heat pump at the H21 test conditions:
where,
The
quantities Q hk=2(47), E hk=2(47), Q hk=1(47),
and E hk=1(47) are determined from the H12 and H11 tests and
evaluated as specified in section 3.7 of this appendix; the
quantities Q hk=2(35) and E hk=2(35) are determined
from the H22 test and evaluated as specified in section 3.9 of this
appendix; and the quantities Q hk=2(17), E hk=2(17),
Q hk=1(17), and E hk=1(17), are determined from the
H32 and H31 tests and evaluated as specified in section 3.10 of
this appendix.
Table 12 - Heating Mode Test Conditions for Units With a Single-Speed Compressor That Meet the Section 3.6.2 Indoor Unit Requirements
| Test description | Air entering
indoor unit temperature ( °F) |
Air entering
outdoor unit temperature ( °F) |
Heating air volume rate | ||
|---|---|---|---|---|---|
| Dry bulb | Wet bulb | Dry bulb | Wet bulb | ||
| H12 Test (required, steady) | 70 | 60 (max) | 47 | 43 | Heating Full-load. 1 |
| H11 Test (required, steady) | 70 | 60 (max) | 47 | 43 | Heating Minimum. 2 |
| H1C1 Test (optional, cyclic) | 70 | 60 (max) | 47 | 43 | ( 3). |
| H22 Test (required) | 70 | 60 (max) | 35 | 33 | Heating Full-load. 1 |
| H21 Test (optional) | 70 | 60 (max) | 35 | 33 | Heating Minimum. 2 |
| H32 Test (required, steady) | 70 | 60 (max) | 17 | 15 | Heating Full-load. 1 |
| H31 Test (required, steady) | 70 | 60 (max) | 17 | 15 | Heating Minimum. 2 |
| H42 Test (optional, steady) | 70 | 60 (max) | 5 | 3 (max) | Heating Full-load. 1 |
1 Defined in section 3.1.4.4 of this appendix.
2 Defined in section 3.1.4.5 of this appendix.
3 Maintain the airflow nozzles static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity pressure as measured during the H11 test.
a. Conduct one maximum temperature test (H01), two high temperature tests (H12 and H11), one frost accumulation test (H22), and one low temperature test (H32). Conducting a very low temperature test (H42) is optional. Conduct an additional frost accumulation test (H21) and low temperature test (H31) if both of the following conditions exist:
(1) Knowledge of the heat pump's capacity and electrical power at low compressor capacity for outdoor temperatures of 37 °F and less is needed to complete the section 4.2.3 of this appendix seasonal performance calculations; and
(2) The heat pump's controls allow low-capacity operation at outdoor temperatures of 37 °F and less.
If the two conditions in a.(1) and a.(2) of this section are met, an alternative to conducting the H21 frost accumulation is to use the following equations to approximate the capacity and electrical power:
Determine the quantities Q hk=1 (47) and E hk=1 (47) from the H11 test and evaluate them according to section 3.7 of this appendix. Determine the quantities Q hk=1 (17) and E hk=1 (17) from the H31 test and evaluate them according to section 3.10 of this appendix.
b. Conduct the optional high temperature cyclic test (H1C1) to determine the heating mode cyclic-degradation coefficient, CD h. If this optional test is conducted but yields a tested CD h that exceeds the default CD h or if the optional test is not conducted, assign CD h the default value of 0.25. If a two-capacity heat pump locks out low capacity operation at lower outdoor temperatures, conduct the high temperature cyclic test (H1C2) to determine the high-capacity heating mode cyclic-degradation coefficient, CD h (k=2). If this optional test at high capacity is conducted but yields a tested CD h (k = 2) that exceeds the default CD h (k = 2) or if the optional test is not conducted, assign CD h the default value. The default CD h (k=2) is the same value as determined or assigned for the low-capacity cyclic-degradation coefficient, CD h [or equivalently, CD h (k=1)]. Table 13 specifies test conditions for these nine tests.
Table 13 - Heating Mode Test Conditions for Units Having a Two-Capacity Compressor
| Test description | Air entering
indoor unit temperature ( °F) |
Air entering
outdoor unit temperature ( °F) |
Compressor capacity | Heating air volume rate | ||
|---|---|---|---|---|---|---|
| Dry bulb | Wet bulb | Dry bulb | Wet bulb | |||
| H01 Test (required, steady) | 70 | 60 (max) | 62 | 56.5 | Low | Heating Minimum. 1 |
| H12 Test (required, steady) | 70 | 60 (max) | 47 | 43 | High | Heating Full-Load. 2 |
| H1C2 Test (optional 7, cyclic) | 70 | 60 (max) | 47 | 43 | High | ( 3) |
| H11 Test (required) | 70 | 60 (max) | 47 | 43 | Low | Heating Minimum. 1 |
| H1C1 Test (optional, cyclic) | 70 | 60 (max) | 47 | 43 | Low | ( 4) |
| H22 Test (required) | 70 | 60 (max) | 35 | 33 | High | Heating Full-Load. 2 |
| H21 Test 5 6 (required) | 70 | 60 (max) | 35 | 33 | Low | Heating Minimum. 1 |
| H32 Test (required, steady) | 70 | 60 (max) | 17 | 15 | High | Heating Full-Load. 2 |
| H31 Test 5 (required, steady) | 70 | 60 (max) | 17 | 15 | Low | Heating Minimum. 1 |
| H42 Test (Optional, steady) | 70 | 60 (max) | 5 | 3 (max) | High | Heating Full-Load. 2 |
1 Defined in section 3.1.4.5 of this appendix.
2 Defined in section 3.1.4.4 of this appendix.
3 Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured during the H12 test.
4 Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured during the H11 test.
5 Required only if the heat pump's performance when operating at low compressor capacity and outdoor temperatures less than 37 °F is needed to complete the section 4.2.3 HSPF2 calculations.
6 If table note #5 applies, the section 3.6.3 equations for Q hk=1 (35) and E hk=1 (17) may be used in lieu of conducting the H21 test.
7 Required only if the heat pump locks out low capacity operation at lower outdoor temperatures.
a. Conduct one maximum temperature test (H01), two high temperature tests (H1N and H11), one frost accumulation test (H2V), and one low temperature test (H32). Conducting one or more of the following tests is optional: An additional high temperature test (H12), an additional frost accumulation test (H22), and a very low temperature test (H42). Conduct the optional high temperature cyclic (H1C1) test to determine the heating mode cyclic-degradation coefficient, CD h. If this optional test is conducted but yields a tested CD h that exceeds the default CD h or if the optional test is not conducted, assign CD h the default value of 0.25. Test conditions for the nine tests are specified in Table 14. The compressor shall operate at the same heating full speed, measured by RPM or power input frequency (Hz), as the maximum speed at which the system controls would operate the compressor in normal operation in 17 °F ambient temperature, for the H12, H22 and H32 Tests. The compressor shall operate for the H1N test at the maximum speed at which the system controls would operate the compressor in normal operation in 47 °F ambient temperature. The compressor shall operate at the same heating minimum speed, measured by RPM or power input frequency (Hz), for the H01, H1C1, and H11 Tests. Determine the heating intermediate compressor speed cited in Table 14 using the heating mode full and minimum compressors speeds and:
Where a
tolerance of plus 5 percent or the next higher inverter frequency
step from that calculated is allowed.
b. If one of the high temperature tests (H12 or H1N) is conducted using the same compressor speed (RPM or power input frequency) as the H32 test, set the 47 °F capacity and power input values used for calculation of HSPF2 equal to the measured values for that test:
Where:
Q hcalck=2(47) and E hcalck=2(47) are the capacity
and power input representing full-speed operation at 47 °F for the
HSPF2 calculations, Q hk=2(47) is the capacity measured in
the high temperature test (H12 or H1N) which used the same
compressor speed as the H32 test, and E hk=2(47) is the
power input measured in the high temperature test (H12 or H1N)
which used the same compressor speed as the H32 test.
Evaluate the quantities Q hk=2(47) and from E hk=2(47) according to section 3.7.
Otherwise (if no high temperature test is conducted using the same speed (RPM or power input frequency) as the H32 test), calculate the 47 °F capacity and power input values used for calculation of HSPF2 as follows:
Where:
Q hcalck=2(47) and E hcalck=2(47) are the capacity
and power input representing full-speed operation at 47 °F for the
HSPF2 calculations, Q hk=2(17) is the capacity measured in
the H32 test, E hk=2(17) is the power input measured in the
H32 test, CSF is the capacity slope factor, equal to 0.0204/ °F for
split systems and 0.0262/ °F for single-package systems, and PSF is
the Power Slope Factor, equal to 0.00455/ °F.
c. If the H22 test is not done, use the following equations to approximate the capacity and electrical power at the H22 test conditions:
Where:
Q hcalck=2(47) and E hcalck=2(47) are the capacity and power input representing full-speed operation at 47 °F for the HSPF2 calculations, calculated as described in section b above.
Q hk=2(17) and E hk=2(17) are the capacity and power input measured in the H32 test.
d. Determine the quantities Q hk=2(17) and E hk=2(17) from the H32 test, determine the quantities Qhk=2(5) and Ehk=2(5) from the H42 test, and evaluate all four according to section 3.10.
Table 14 - Heating Mode Test Conditions for Units Having a Variable-Speed Compressor
| Test description | Air entering indoor unit temperature ( °F) |
Air entering outdoor unit temperature ( °F) |
Compressor speed | Heating air volume rate | ||
|---|---|---|---|---|---|---|
| Dry bulb | Wet bulb | Dry bulb | Wet bulb | |||
| H01 test (required, steady) | 70 | 60 (max) | 62 | 56.5 | Heating Minimum | Heating Minimum. 1 |
| H12 test (optional, steady) | 70 | 60 (max) | 47 | 43 | Heating Full 4 | Heating Full-Load. 3 |
| H11 test (required, steady) | 70 | 60 (max) | 47 | 43 | Heating Minimum | Heating Minimum. 1 |
| H1N test (required, steady) | 70 | 60 (max) | 47 | 43 | Heating Full 5 | Heating Full-Load. 3 |
| H1C1 test (optional, cyclic) | 70 | 60 (max) | 47 | 43 | Heating Minimum | ( 2) |
| H22 test (optional) | 70 | 60 (max) | 35 | 33 | Heating Full 4 | Heating Full-Load. 3 |
| H2V test (required) | 70 | 60 (max) | 35 | 33 | Heating Intermediate | Heating Intermediate. 6 |
| H32 test (required, steady) | 70 | 60 (max) | 17 | 15 | Heating Full 4 | Heating Full-Load. 3 |
| H42 test (optional, steady) | 70 | 60 (max) | 5 | 3 (max) | Heating Full | Heating Full-Load. 3 |
1 Defined in section 3.1.4.5 of this appendix.
2 Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured during the H11 test.
3 Defined in section 3.1.4.4 of this appendix.
4 Maximum speed that the system controls would operate the compressor in normal operation in 17 °F ambient temperature. The H12 test is not needed if the H1N test uses this same compressor speed.
5 Maximum speed that the system controls would operate the compressor in normal operation in 47 °F ambient temperature.
6 Defined in section 3.1.4.6 of this appendix.
e. For multiple-split heat pumps (only), the following procedures supersede the above requirements. For all Table 14 tests specified for a minimum compressor speed, turn off at least one indoor unit. The manufacturer shall designate the particular indoor unit(s) that is turned off. The manufacturer must also specify the compressor speed used for the Table 14 H2V test, a heating mode intermediate compressor speed that falls within 1/4 and 3/4 of the difference between the full and minimum heating mode speeds. The manufacturer should prescribe an intermediate speed that is expected to yield the highest COP for the given H2V test conditions and bracketed compressor speed range. The manufacturer can designate that one or more specific indoor units are turned off for the H2V test.
3.6.5 Additional Test for a Heat Pump Having a Heat Comfort ControllerTest any heat pump that has a heat comfort controller (see section 1.2 of this appendix, Definitions) according to section 3.6.1, 3.6.2, or 3.6.3, whichever applies, with the heat comfort controller disabled. Additionally, conduct the abbreviated test described in section 3.1.9 of this appendix with the heat comfort controller active to determine the system's maximum supply air temperature. ( Note: heat pumps having a variable-speed compressor and a heat comfort controller are not covered in the test procedure at this time.)
3.6.6 Heating Mode Tests for Northern Heat Pumps with Triple-Capacity CompressorsTest triple-capacity, northern heat pumps for the heating mode as follows:
a. Conduct one maximum temperature test (H01), two high temperature tests (H12 and H11), one frost accumulation test (H22), two low temperature tests (H32, H33), and one very low temperature test (H43). Conduct an additional frost accumulation test (H21) and low temperature test (H31) if both of the following conditions exist: (1) Knowledge of the heat pump's capacity and electrical power at low compressor capacity for outdoor temperatures of 37 °F and less is needed to complete the section 4.2.6 seasonal performance calculations; and (2) the heat pump's controls allow low capacity operation at outdoor temperatures of 37 °F and less. If the above two conditions are met, an alternative to conducting the H21 frost accumulation test to determine Q hk=1(35) and Ehk=1(35) is to use the following equations to approximate this capacity and electrical power:
In evaluating the above equations, determine the quantities Qhk=1(47) from the H11 test and evaluate them according to section 3.7 of this appendix. Determine the quantities Q hk=1(17) and E hk=1(17) from the H31 test and evaluate them according to section 3.10 of this appendix. Use the paired values of Q hk=1(35) and E hk=1(35) derived from conducting the H21 frost accumulation test and evaluated as specified in section 3.9.1 of this appendix or use the paired values calculated using the above default equations, whichever contribute to a higher Region IV HSPF2 based on the DHRmin.
b. Conducting a frost accumulation test (H23) with the heat pump operating at its booster capacity is optional. If this optional test is not conducted, determine Q hk=3(35) and E hk=3(35) using the following equations to approximate this capacity and electrical power:
Where:Determine the quantities Q hk=2(47) and E hk=2(47) from the H12 test and evaluate them according to section 3.7 of this appendix. Determine the quantities Q hk=2(35) and E hk=2(35) from the H22 test and evaluate them according to section 3.9.1 of this appendix. Determine the quantities Q hk=2(17) and E hk=2(17) from the H32 test, determine the quantities Q hk=3(17) and E hk=3(17) from the H33 test, and determine the quantities Q hk=3(5) and E hk=3(5) from the H43 test. Evaluate all six quantities according to section 3.10 of this appendix. Use the paired values of Q hk=3(35) and E hk=3(35) derived from conducting the H23 frost accumulation test and calculated as specified in section 3.9.1 of this appendix or use the paired values calculated using the above default equations, whichever contribute to a higher Region IV HSPF2 based on the DHRmin.
c. Conduct the optional high temperature cyclic test (H1C1) to determine the heating mode cyclic-degradation coefficient, CD h. A default value for CD h of 0.25 may be used in lieu of conducting the cyclic. If a triple-capacity heat pump locks out low capacity operation at lower outdoor temperatures, conduct the high temperature cyclic test (H1C2) to determine the high capacity heating mode cyclic-degradation coefficient, CD h (k=2). The default CD h (k=2) is the same value as determined or assigned for the low-capacity cyclic-degradation coefficient, CD h [or equivalently, CD h (k=1)]. Finally, if a triple-capacity heat pump locks out both low and high capacity operation at the lowest outdoor temperatures, conduct the low temperature cyclic test (H3C3) to determine the booster-capacity heating mode cyclic-degradation coefficient, CD h (k=3). The default CD h (k=3) is the same value as determined or assigned for the high capacity cyclic-degradation coefficient, CD h [or equivalently, CD h (k=2)]. Table 15 specifies test conditions for all 13 tests.
Table 15 - Heating Mode Test Conditions for Units With a Triple-Capacity Compressor
| Test description | Air entering
indoor unit temperature °F |
Air entering
outdoor unit temperature °F |
Compressor capacity |
Heating air volume rate |
||
|---|---|---|---|---|---|---|
| Dry bulb | Wet bulb | Dry bulb | Wet bulb | |||
| H01 Test (required, steady) | 70 | 60 (max) | 62 | 56.5 | Low | Heating Minimum 1 |
| H12 Test (required, steady) | 70 | 60 (max) | 47 | 43 | High | Heating Full-Load 2 |
| H1C2 Test (optional, 8 cyclic) | 70 | 60 (max) | 47 | 43 | High | ( 3) |
| H11 Test (required) | 70 | 60 (max) | 47 | 43 | Low | Heating Minimum 1 |
| H1C1 Test (optional, cyclic) | 70 | 60 (max) | 47 | 43 | Low | ( 4) |
| H23 Test (optional, steady) | 70 | 60 (max) | 35 | 33 | Booster | Heating Full-Load 2 |
| H22 Test (required) | 70 | 60 (max) | 35 | 33 | High | Heating Full-Load 2 |
| H21 Test (required) | 70 | 60 (max) | 35 | 33 | Low | Heating Minimum 1 |
| H33 Test (required, steady) | 70 | 60 (max) | 17 | 15 | Booster | Heating Full-Load 2 |
| H3C3 Test 5 6 (optional, cyclic) | 70 | 60(max) | 17 | 15 | Booster | ( 7) |
| H32 Test (required, steady) | 70 | 60 (max) | 17 | 15 | High | Heating Full-Load 2 |
| H31 Test 5 (required, steady) | 70 | 60 (max) | 17 | 15 | Low | Heating Minimum 1 |
| H43 Test (required, steady) | 70 | 60 (max) | 5 | 3 (max) | Booster | Heating Full-Load 2 |
1 Defined in section 3.1.4.5 of this appendix.
2 Defined in section 3.1.4.4 of this appendix.
3 Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured during the H12 test.
4 Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured during the H11 test.
5 Required only if the heat pump's performance when operating at low compressor capacity and outdoor temperatures less than 37 °F is needed to complete the section 4.2.6 HSPF2 calculations.
6 If table note 5 applies, the section 3.6.6 equations for Q hk=1(35) and E hk=1(17) may be used in lieu of conducting the H21 test.
7 Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured during the H33 test.
8 Required only if the heat pump locks out low capacity operation at lower outdoor temperatures
a. For the pretest interval, operate the test room reconditioning apparatus and the heat pump until equilibrium conditions are maintained for at least 30 minutes at the specified section 3.6 test conditions. Use the exhaust fan of the airflow measuring apparatus and, if installed, the indoor blower of the heat pump to obtain and then maintain the indoor air volume rate and/or the external static pressure specified for the particular test. Continuously record the dry-bulb temperature of the air entering the indoor coil, and the dry-bulb temperature and water vapor content of the air entering the outdoor coil. Refer to section 3.11 of this appendix for additional requirements that depend on the selected secondary test method. After satisfying the pretest equilibrium requirements, make the measurements specified in Table 3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3) for the indoor air enthalpy method and the user-selected secondary method. Make said Table 3 measurements at equal intervals that span 5 minutes or less. Continue data sampling until a 30-minute period (e.g., seven consecutive 5-minute samples) is reached where the test tolerances specified in Table 16 are satisfied. For those continuously recorded parameters, use the entire data set for the 30-minute interval when evaluating Table 16 compliance. Determine the average electrical power consumption of the heat pump over the same 30-minute interval.
Table 16 - Test Operating and Test Condition Tolerances for Section 3.7 and Section 3.10 Steady-State Heating Mode Tests
| Test operating tolerance 1 | Test condition tolerance 1 | |
|---|---|---|
| Indoor dry-bulb, °F: | ||
| Entering temperature | 2.0 | 0.5 |
| Leaving temperature | 2.0 | |
| Indoor wet-bulb, °F: | ||
| Entering temperature | 1.0 | |
| Leaving temperature | 1.0 | |
| Outdoor dry-bulb, °F: | ||
| Entering temperature | 2.0 | 0.5 |
| Leaving temperature | 22.0 | |
| Outdoor wet-bulb, °F: | ||
| Entering temperature | 1.0 | 0.3 |
| Leaving temperature | 2 1.0 | |
| External resistance to airflow, inches of water | 0.05 | 3 0.02 |
| Electrical voltage, % of reading | 2.0 | 1.5 |
| Nozzle pressure drop, % of reading | 2.0 |
1 See section 1.2 of this appendix, Definitions.
2 Only applies when the Outdoor Air Enthalpy Method is used.
3 Only applies when testing non-ducted units.
b. Calculate indoor-side total heating capacity as specified in sections 7.3.4.1 and 7.3.4.3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3). To calculate capacity, use the averages of the measurements (e.g. inlet and outlet dry bulb temperatures measured at the psychrometers) that are continuously recorded for the same 30-minute interval used as described above to evaluate compliance with test tolerances. Do not adjust the parameters used in calculating capacity for the permitted variations in test conditions. Assign the average space heating capacity and electrical power over the 30-minute data collection interval to the variables Q h k and E h k(T) respectively. The “T” and superscripted “k” are the same as described in section 3.3 of this appendix. Additionally, for the heating mode, use the superscript to denote results from the optional H1N test, if conducted.
c. For mobile home and space-constrained coil-only system heat pumps, increase Q h k(T) by
where V s is the average measured indoor air volume rate expressed in units of cubic feet per minute of standard air (scfm).For non-mobile home, non-space-constrained coil-only system heat pumps, increase Q h k(T) by
where V s is the average measured indoor air volume rate expressed in units of cubic feet per minute of standard air (scfm). During the 30-minute data collection interval of a high temperature test, pay attention to preventing a defrost cycle. Prior to this time, allow the heat pump to perform a defrost cycle if automatically initiated by its own controls. As in all cases, wait for the heat pump's defrost controls to automatically terminate the defrost cycle. Heat pumps that undergo a defrost cycle should operate in the heating mode for at least 10 minutes after defrost termination prior to beginning the 30-minute data collection interval. For some heat pumps, frost may accumulate on the outdoor coil during a high temperature test. If the indoor coil leaving air temperature or the difference between the leaving and entering air temperatures decreases by more than 1.5 °F over the 30-minute data collection interval, then do not use the collected data to determine capacity. Instead, initiate a defrost cycle. Begin collecting data no sooner than 10 minutes after defrost termination. Collect 30 minutes of new data during which the Table 16 test tolerances are satisfied. In this case, use only the results from the second 30-minute data collection interval to evaluate Q h k(47) and E h k(47).d. If conducting the cyclic heating mode test, which is described in section 3.8 of this appendix, record the average indoor-side air volume rate, V , specific heat of the air, Cp,a (expressed on dry air basis), specific volume of the air at the nozzles, vn′ (or vn), humidity ratio at the nozzles, Wn, and either pressure difference or velocity pressure for the flow nozzles. If either or both of the below criteria apply, determine the average, steady-state, electrical power consumption of the indoor blower motor (E fan,1):
(1) The section 3.8 cyclic test will be conducted and the heat pump has a variable-speed indoor blower that is expected to be disabled during the cyclic test; or
(2) The heat pump has a (variable-speed) constant-air volume-rate indoor blower and during the steady-state test the average external static pressure (ΔP1) exceeds the applicable section 3.1.4.4 minimum (or targeted) external static pressure (ΔPmin) by 0.03 inches of water or more.
Determine E fan,1 by making measurements during the 30-minute data collection interval, or immediately following the test and prior to changing the test conditions. When the above “2” criteria applies, conduct the following four steps after determining E fan,1 (which corresponds to ΔP1):
(i) While maintaining the same test conditions, adjust the exhaust fan of the airflow measuring apparatus until the external static pressure increases to approximately ΔP1 + (ΔP1 − ΔPmin).
(ii) After re-establishing steady readings for fan motor power and external static pressure, determine average values for the indoor blower power (E fan,2) and the external static pressure (ΔP2) by making measurements over a 5-minute interval.
(iii) Approximate the average power consumption of the indoor blower motor if the 30-minute test had been conducted at ΔPmin using linear extrapolation:
(iv) Decrease the total space heating capacity, Q h k(T), by the quantity (E fan,1 − E fan,min), when expressed on a Btu/h basis. Decrease the total electrical power, E h k(T) by the same fan power difference, now expressed in watts.
e. If the temperature sensors used to provide the primary measurement of the indoor-side dry bulb temperature difference during the steady-state dry-coil test and the subsequent cyclic dry-coil test are different, include measurements of the latter sensors among the regularly sampled data. Beginning at the start of the 30-minute data collection period, measure and compute the indoor-side air dry-bulb temperature difference using both sets of instrumentation, ΔT (Set SS) and ΔT (Set CYC), for each equally spaced data sample. If using a consistent data sampling rate that is less than 1 minute, calculate and record minutely averages for the two temperature differences. If using a consistent sampling rate of one minute or more, calculate and record the two temperature differences from each data sample. After having recorded the seventh (i=7) set of temperature differences, calculate the following ratio using the first seven sets of values:
Each time a subsequent set of temperature differences is recorded (if sampling more frequently than every 5 minutes), calculate FCD using the most recent seven sets of values. Continue these calculations until the 30-minute period is completed or until a value for FCD is calculated that falls outside the allowable range of 0.94-1.06. If the latter occurs, immediately suspend the test and identify the cause for the disparity in the two temperature difference measurements. Recalibration of one or both sets of instrumentation may be required. If all the values for FCD are within the allowable range, save the final value of the ratio from the 30-minute test as FCD*. If the temperature sensors used to provide the primary measurement of the indoor-side dry bulb temperature difference during the steady-state dry-coil test and the subsequent cyclic dry-coil test are the same, set FCD*= 1. 3.8 Test Procedures for the Cyclic Heating Mode Tests (the H0C1, H1C, H1C1 and H1C2 Tests).a. Except as noted below, conduct the cyclic heating mode test as specified in section 3.5 of this appendix. As adapted to the heating mode, replace section 3.5 references to “the steady-state dry coil test” with “the heating mode steady-state test conducted at the same test conditions as the cyclic heating mode test.” Use the test tolerances in Table 17 rather than Table 10. Record the outdoor coil entering wet-bulb temperature according to the requirements given in section 3.5 of this appendix for the outdoor coil entering dry-bulb temperature. Drop the subscript “dry” used in variables cited in section 3.5 of this appendix when referring to quantities from the cyclic heating mode test. If available, use electric resistance heaters (see section 2.1 of this appendix) to minimize the variation in the inlet air temperature. Determine the total space heating delivered during the cyclic heating test, qcyc, as specified in section 3.5 of this appendix except for making the following changes:
(1) When evaluating Equation 3.5-1, use the values of V , Cp,a,vn′, (or vn), and Wn that were recorded during the section 3.7 steady-state test conducted at the same test conditions.
(2) Calculate
where FCD* is the value recorded during the section 3.7 steady-state test conducted at the same test condition.b. For ducted coil-only system heat pumps (excluding the special case where a variable-speed fan is temporarily removed), increase qcyc by the amount calculated using Equation 3.5-3. Additionally, increase ecyc by the amount calculated using Equation 3.5-2. In making these calculations, use the average indoor air volume rate (V s) determined from the section 3.7 steady-state heating mode test conducted at the same test conditions.
c. For non-ducted heat pumps, subtract the electrical energy used by the indoor blower during the 3 minutes after compressor cutoff from the non-ducted heat pump's integrated heating capacity, qcyc.
d. If a heat pump defrost cycle is manually or automatically initiated immediately prior to or during the OFF/ON cycling, operate the heat pump continuously until 10 minutes after defrost termination. After that, begin cycling the heat pump immediately or delay until the specified test conditions have been re-established. Pay attention to preventing defrosts after beginning the cycling process. For heat pumps that cycle off the indoor blower during a defrost cycle, make no effort here to restrict the air movement through the indoor coil while the fan is off. Resume the OFF/ON cycling while conducting a minimum of two complete compressor OFF/ON cycles before determining qcyc and ecyc.
3.8.1 Heating Mode Cyclic-Degradation Coefficient CalculationUse the results from the required cyclic test and the required steady-state test that were conducted at the same test conditions to determine the heating mode cyclic-degradation coefficient CDh. Add “(k=2)” to the coefficient if it corresponds to a two-capacity unit cycling at high capacity. For the below calculation of the heating mode cyclic degradation coefficient, do not include the duct loss correction from section 7.3.3.3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3) in determining Q h k(Tcyc) (or qcyc). If the optional cyclic test is conducted but yields a tested CDh that exceeds the default CDh or if the optional test is not conducted, assign CDh the default value of 0.25. The default value for two-capacity units cycling at high capacity, however, is the low-capacity coefficient, i.e., CDh (k=2) = CDh. The tested CDh is calculated as follows:
Where: the average coefficient of performance during the cyclic heating mode test, dimensionless. the average coefficient of performance during the steady-state heating mode test conducted at the same test conditions - i.e., same outdoor dry bulb temperature, Tcyc, and speed/capacity, k, if applicable - as specified for the cyclic heating mode test, dimensionless. the heating load factor, dimensionless. Tcyc = the nominal outdoor temperature at which the cyclic heating mode test is conducted, 62 or 47 °F. Δτcyc = the duration of the OFF/ON intervals; 0.5 hours when testing a heat pump having a single-speed or two-capacity compressor and 1.0 hour when testing a heat pump having a variable-speed compressor.Round the calculated value for CDh to the nearest 0.01. If CDh is negative, then set it equal to zero.
Table 17 - Test Operating and Test Condition Tolerances for Cyclic Heating Mode Tests
| Test operating tolerance 1 | Test condition tolerance 1 | |
|---|---|---|
| Indoor entering dry-bulb temperature, 2 °F | 2.0 | 0.5 |
| Indoor entering wet-bulb temperature, 2 °F | 1.0 | |
| Outdoor entering dry-bulb temperature, 2 °F | 2.0 | 0.5 |
| Outdoor entering wet-bulb temperature, 2 °F | 2.0 | 1.0 |
| External resistance to air-flow, 2 inches of water | 0.05 | |
| Airflow nozzle pressure difference or velocity pressure, 2% of reading | 2.0 | 3 2.0 |
| Electrical voltage, 4% of reading | 2.0 | 1.5 |
1 See section 1.2 of this appendix, Definitions.
2 Applies during the interval that air flows through the indoor (outdoor) coil except for the first 30 seconds after flow initiation. For units having a variable-speed indoor blower that ramps, the tolerances listed for the external resistance to airflow shall apply from 30 seconds after achieving full speed until ramp down begins.
3 The test condition must be the average nozzle pressure difference or velocity pressure measured during the steady-state test conducted at the same test conditions.
4 Applies during the interval that at least one of the following - the compressor, the outdoor fan, or, if applicable, the indoor blower - are operating, except for the first 30 seconds after compressor start-up.
a. Confirm that the defrost controls of the heat pump are set as specified in section 2.2.1 of this appendix. Operate the test room reconditioning apparatus and the heat pump for at least 30 minutes at the specified section 3.6 test conditions before starting the “preliminary” test period. The preliminary test period must immediately precede the “official” test period, which is the heating and defrost interval over which data are collected for evaluating average space heating capacity and average electrical power consumption.
b. For heat pumps containing defrost controls which are likely to cause defrosts at intervals less than one hour, the preliminary test period starts at the termination of an automatic defrost cycle and ends at the termination of the next occurring automatic defrost cycle. For heat pumps containing defrost controls which are likely to cause defrosts at intervals exceeding one hour, the preliminary test period must consist of a heating interval lasting at least one hour followed by a defrost cycle that is either manually or automatically initiated. In all cases, the heat pump's own controls must govern when a defrost cycle terminates.
c. The official test period begins when the preliminary test period ends, at defrost termination. The official test period ends at the termination of the next occurring automatic defrost cycle. When testing a heat pump that uses a time-adaptive defrost control system (see section 1.2 of this appendix, Definitions), however, manually initiate the defrost cycle that ends the official test period at the instant indicated by instructions provided by the manufacturer. If the heat pump has not undergone a defrost after 6 hours, immediately conclude the test and use the results from the full 6-hour period to calculate the average space heating capacity and average electrical power consumption.
For heat pumps that turn the indoor blower off during the defrost cycle, take steps to cease forced airflow through the indoor coil and block the outlet duct whenever the heat pump's controls cycle off the indoor blower. If it is installed, use the outlet damper box described in section 2.5.4.1 of this appendix to affect the blocked outlet duct.
d. Defrost termination occurs when the controls of the heat pump actuate the first change in converting from defrost operation to normal heating operation. Defrost initiation occurs when the controls of the heat pump first alter its normal heating operation in order to eliminate possible accumulations of frost on the outdoor coil.
e. To constitute a valid frost accumulation test, satisfy the test tolerances specified in Table 18 during both the preliminary and official test periods. As noted in Table 18, test operating tolerances are specified for two sub-intervals:
(1) When heating, except for the first 10 minutes after the termination of a defrost cycle (sub-interval H, as described in Table 18) and
(2) When defrosting, plus these same first 10 minutes after defrost termination (sub-interval D, as described in Table 18). Evaluate compliance with Table 18 test condition tolerances and the majority of the test operating tolerances using the averages from measurements recorded only during sub-interval H. Continuously record the dry bulb temperature of the air entering the indoor coil, and the dry bulb temperature and water vapor content of the air entering the outdoor coil. Sample the remaining parameters listed in Table 18 at equal intervals that span 5 minutes or less.
f. For the official test period, collect and use the following data to calculate average space heating capacity and electrical power. During heating and defrosting intervals when the controls of the heat pump have the indoor blower on, continuously record the dry-bulb temperature of the air entering (as noted above) and leaving the indoor coil. If using a thermopile, continuously record the difference between the leaving and entering dry-bulb temperatures during the interval(s) that air flows through the indoor coil. For coil-only system heat pumps, determine the corresponding cumulative time (in hours) of indoor coil airflow, Δτa. Sample measurements used in calculating the air volume rate (refer to sections 7.7.2.1 and 7.7.2.2 of ANSI/ASHRAE 37-2009) at equal intervals that span 10 minutes or less. (Note: In the first printing of ANSI/ASHRAE 37-2009, the second IP equation for Qmi should read:) Record the electrical energy consumed, expressed in watt-hours, from defrost termination to defrost termination, eDEF k(35), as well as the corresponding elapsed time in hours, ΔτFR.
Table 18 - Test Operating and Test Condition Tolerances for Frost Accumulation Heating Mode Tests
| Test operating tolerance 1 | Test condition tolerance 1 Sub-interval H 2 | ||
|---|---|---|---|
| Sub-interval H 2 | Sub-interval D 3 | ||
| Indoor entering dry-bulb temperature, °F | 2.0 | 4 4.0 | 0.5 |
| Indoor entering wet-bulb temperature, °F | 1.0 | ||
| Outdoor entering dry-bulb temperature, °F | 2.0 | 10.0 | 1.0 |
| Outdoor entering wet-bulb temperature, °F | 1.5 | 0.5 | |
| External resistance to airflow, inches of water | 0.05 | 5 0.02 | |
| Electrical voltage, % of reading | 2.0 | 1.5 | |
1 See section 1.2 of this appendix, Definitions.
2 Applies when the heat pump is in the heating mode, except for the first 10 minutes after termination of a defrost cycle.
3 Applies during a defrost cycle and during the first 10 minutes after the termination of a defrost cycle when the heat pump is operating in the heating mode.
4 For heat pumps that turn off the indoor blower during the defrost cycle, the noted tolerance only applies during the 10 minute interval that follows defrost termination.
5 Only applies when testing non-ducted heat pumps.
a. Evaluate average space heating capacity, Q h k(35), when expressed in units of Btu per hour, using:
where, V = the average indoor air volume rate measured during sub-interval H, cfm. Cp,a = 0.24 + 0.444 · Wn, the constant pressure specific heat of the air-water vapor mixture that flows through the indoor coil and is expressed on a dry air basis, Btu/lbmda · °F. vn′ = specific volume of the air-water vapor mixture at the nozzle, ft 3/lbmmx. Wn = humidity ratio of the air-water vapor mixture at the nozzle, lbm of water vapor per lbm of dry air. ΔτFR = τ2 − τ1, the elapsed time from defrost termination to defrost termination, hr. Tal(τ) = dry bulb temperature of the air entering the indoor coil at elapsed time τ, °F; only recorded when indoor coil airflow occurs; assigned the value of zero during periods (if any) where the indoor blower cycles off. Ta2(τ) = dry bulb temperature of the air leaving the indoor coil at elapsed time τ, °F; only recorded when indoor coil airflow occurs; assigned the value of zero during periods (if any) where the indoor blower cycles off. τ1 = the elapsed time when the defrost termination occurs that begins the official test period, hr. τ2 = the elapsed time when the next automatically occurring defrost termination occurs, thus ending the official test period, hr. vn = specific volume of the dry air portion of the mixture evaluated at the dry-bulb temperature, vapor content, and barometric pressure existing at the nozzle, ft 3 per lbm of dry air.To account for the effect of duct losses between the outlet of the indoor unit and the section 2.5.4 dry-bulb temperature grid, adjust Q h k(35) in accordance with section 7.3.4.3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3).
b. Evaluate average electrical power, E h k(35), when expressed in units of watts, using:
For mobile home and space-constrained coil-only system heat pumps, increase Q h k(35) bywhere V s is the average measured indoor air volume rate expressed in units of cubic feet per minute of standard air (scfm).
For non-mobile home, non-space-constrained coil-only system heat pumps, increase Q h k(35) by
where V s is the average measured indoor air volume rate expressed in units of cubic feet per minute of standard air (scfm).c. For heat pumps having a constant-air-volume-rate indoor blower, the five additional steps listed below are required if the average of the external static pressures measured during sub-interval H exceeds the applicable section 3.1.4.4, 3.1.4.5, or 3.1.4.6 minimum (or targeted) external static pressure (ΔPmin) by 0.03 inches of water or more:
(1) Measure the average power consumption of the indoor blower motor (E fan,1) and record the corresponding external static pressure (ΔP1) during or immediately following the frost accumulation heating mode test. Make the measurement at a time when the heat pump is heating, except for the first 10 minutes after the termination of a defrost cycle.
(2) After the frost accumulation heating mode test is completed and while maintaining the same test conditions, adjust the exhaust fan of the airflow measuring apparatus until the external static pressure increases to approximately ΔP1 + (ΔP1 − ΔPmin).
(3) After re-establishing steady readings for the fan motor power and external static pressure, determine average values for the indoor blower power (E fan,2) and the external static pressure (ΔP2) by making measurements over a 5-minute interval.
(4) Approximate the average power consumption of the indoor blower motor had the frost accumulation heating mode test been conducted at ΔPmin using linear extrapolation:
(5) Decrease the total heating capacity, Q h k(35), by the quantity [(E fan,1 − E fan,min)· (Δτ a/Δτ FR], when expressed on a Btu/h basis. Decrease the total electrical power, Eh k(35), by the same quantity, now expressed in watts.
3.9.2 Demand Defrost Credita. Assign the demand defrost credit, Fdef, that is used in section 4.2 of this appendix to the value of 1 in all cases except for heat pumps having a demand-defrost control system (see section 1.2 of this appendix, Definitions). For such qualifying heat pumps, evaluate Fdef using,
where: Δτdef = the time between defrost terminations (in hours) or 1.5, whichever is greater. Assign a value of 6 to Δτdef if this limit is reached during a frost accumulation test and the heat pump has not completed a defrost cycle. Δτmax = maximum time between defrosts as allowed by the controls (in hours) or 12, whichever is less, as provided in the certification report.b. For two-capacity heat pumps and for section 3.6.2 units, evaluate the above equation using the Δτdef that applies based on the frost accumulation test conducted at high capacity and/or at the heating full-load air volume rate. For variable-speed heat pumps, evaluate Δτdef based on the required frost accumulation test conducted at the intermediate compressor speed.
3.10 Test Procedures for Steady-State Low Temperature and Very Low Temperature Heating Mode Tests (the H3, H32, H31, H33, H4, H42, and H43 Tests)Except for the modifications noted in this section, conduct the low temperature and very low temperature heating mode tests using the same approach as specified in section 3.7 of this appendix for the maximum and high temperature tests. After satisfying the section 3.7 requirements for the pretest interval but before beginning to collect data to determine the capacity and power input, conduct a defrost cycle. This defrost cycle may be manually or automatically initiated. Terminate the defrost sequence using the heat pump's defrost controls. Begin the 30-minute data collection interval described in section 3.7 of this appendix, from which the capacity and power input are determined, no sooner than 10 minutes after defrost termination. Defrosts should be prevented over the 30-minute data collection interval.
3.11 Additional Requirements for the Secondary Test Methods 3.11.1 If Using the Outdoor Air Enthalpy Method as the Secondary Test Method.a. For all cooling mode and heating mode tests, first conduct a test without the outdoor air-side test apparatus described in section 2.10.1 of this appendix connected to the outdoor unit (“free outdoor air” test).
b. For the first section 3.2 steady-state cooling mode test and the first section 3.6 steady-state heating mode test, conduct a second test in which the outdoor-side apparatus is connected (“ducted outdoor air” test). No other cooling mode or heating mode tests require the ducted outdoor air test so long as the unit operates the outdoor fan during all cooling mode steady-state tests at the same speed and all heating mode steady-state tests at the same speed. If using more than one outdoor fan speed for the cooling mode steady-state tests, however, conduct the ducted outdoor air test for each cooling mode test where a different fan speed is first used. This same requirement applies for the heating mode tests.
3.11.1.1 Free Outdoor Air Testa. For the free outdoor air test, connect the indoor air-side test apparatus to the indoor coil; do not connect the outdoor air-side test apparatus. Allow the test room reconditioning apparatus and the unit being tested to operate for at least one hour. After attaining equilibrium conditions, measure the following quantities at equal intervals that span 5 minutes or less:
(1) The section 2.10.1 evaporator and condenser temperatures or pressures;
(2) Parameters required according to the Indoor Air Enthalpy Method.
Continue these measurements until a 30-minute period (e.g., seven consecutive 5-minute samples) is obtained where the Table 9 or Table 16, whichever applies, test tolerances are satisfied.
b. For cases where a ducted outdoor air test is not required per section 3.11.1.b of this appendix, the free outdoor air test constitutes the “official” test for which validity is not based on comparison with a secondary test.
c. For cases where a ducted outdoor air test is required per section 3.11.1.b of this appendix, the following conditions must be met for the free outdoor air test to constitute a valid “official” test:
(1) The energy balance specified in section 3.1.1 of this appendix is achieved for the ducted outdoor air test (i.e., compare the capacities determined using the indoor air enthalpy method and the outdoor air enthalpy method).
(2) The capacities determined using the indoor air enthalpy method from the ducted outdoor air and free outdoor air tests must agree within 2 percent.
3.11.1.2 Ducted Outdoor Air Testa. The test conditions and tolerances for the ducted outdoor air test are the same as specified for the official test, where the official test is the free outdoor air test described in section 3.11.1.1 of this appendix.
b. After collecting 30 minutes of steady-state data during the free outdoor air test, connect the outdoor air-side test apparatus to the unit for the ducted outdoor air test. Adjust the exhaust fan of the outdoor airflow measuring apparatus until averages for the evaporator and condenser temperatures, or the saturated temperatures corresponding to the measured pressures, agree within ±0.5 °F of the averages achieved during the free outdoor air test. Collect 30 minutes of steady-state data after re-establishing equilibrium conditions.
c. During the ducted outdoor air test, at intervals of 5 minutes or less, measure the parameters required according to the indoor air enthalpy method and the outdoor air enthalpy method for the prescribed 30 minutes.
d. For cooling mode ducted outdoor air tests, calculate capacity based on outdoor air-enthalpy measurements as specified in sections 7.3.3.2 and 7.3.3.3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3). For heating mode ducted tests, calculate heating capacity based on outdoor air-enthalpy measurements as specified in sections 7.3.4.2 and 7.3.3.4.3 of the same ANSI/ASHRAE Standard. Adjust the outdoor-side capacity according to section 7.3.3.4 of ANSI/ASHRAE 37-2009 to account for line losses when testing split systems. As described in section 8.6.2 of ANSI/ASHRAE 37-2009, use the outdoor air volume rate as measured during the ducted outdoor air tests to calculate capacity for checking the agreement with the capacity calculated using the indoor air enthalpy method.
3.11.2 If Using the Compressor Calibration Method as the Secondary Test Methoda. Conduct separate calibration tests using a calorimeter to determine the refrigerant flow rate. Or for cases where the superheat of the refrigerant leaving the evaporator is less than 5 °F, use the calorimeter to measure total capacity rather than refrigerant flow rate. Conduct these calibration tests at the same test conditions as specified for the tests in this appendix. Operate the unit for at least one hour or until obtaining equilibrium conditions before collecting data that will be used in determining the average refrigerant flow rate or total capacity. Sample the data at equal intervals that span 5 minutes or less. Determine average flow rate or average capacity from data sampled over a 30-minute period where the Table 9 (cooling) or the Table 16 (heating) tolerances are satisfied. Otherwise, conduct the calibration tests according to sections 5, 6, 7, and 8 of ASHRAE 23.1-2010 (incorporated by reference, see § 430.3); sections 5, 6, 7, 8, 9, and 11 of ASHRAE 41.9-2011 (incorporated by reference, see § 430.3); and section 7.4 of ANSI/ASHRAE 37-2009 (incorporated by reference, see § 430.3).
b. Calculate space cooling and space heating capacities using the compressor calibration method measurements as specified in section 7.4.5 and 7.4.6 respectively, of ANSI/ASHRAE 37-2009.
3.11.3 If Using the Refrigerant-Enthalpy Method as the Secondary Test MethodConduct this secondary method according to section 7.5 of ANSI/ASHRAE 37-2009. Calculate space cooling and heating capacities using the refrigerant-enthalpy method measurements as specified in sections 7.5.4 and 7.5.5, respectively, of the same ANSI/ASHRAE Standard.
3.12 Rounding of Space Conditioning Capacities for Reporting Purposesa. When reporting rated capacities, round them off as specified in § 430.23 (for a single unit) and in 10 CFR 429.16 (for a sample).
b. For the capacities used to perform the calculations in section 4 of this appendix, however, round only to the nearest integer.
3.13 Laboratory Testing To Determine Off Mode Average Power RatingsVoltage tolerances: As a percentage of reading, test operating tolerance must be 2.0 percent and test condition tolerance must be 1.5 percent (see section 1.2 of this appendix for definitions of these tolerances).
Conduct one of the following tests: If the central air conditioner or heat pump lacks a compressor crankcase heater, perform the test in section 3.13.1 of this appendix; if the central air conditioner or heat pump has a compressor crankcase heater that lacks controls and is not self-regulating, perform the test in section 3.13.1 of this appendix; if the central air conditioner or heat pump has a crankcase heater with a fixed power input controlled with a thermostat that measures ambient temperature and whose sensing element temperature is not affected by the heater, perform the test in section 3.13.1 of this appendix; if the central air conditioner or heat pump has a compressor crankcase heater equipped with self-regulating control or with controls for which the sensing element temperature is affected by the heater, perform the test in section 3.13.2 of this appendix.
3.13.1 This Test Determines the Off Mode Average Power Rating for Central Air Conditioners and Heat Pumps That Lack a Compressor Crankcase Heater, or Have a Compressor Crankcase Heating System That Can Be Tested Without Control of Ambient Temperature During the Test. This Test Has No Ambient Condition Requirementsa. Test Sample Set-up and Power Measurement: For coil-only systems, provide a furnace or modular blower that is compatible with the system to serve as an interface with the thermostat (if used for the test) and to provide low-voltage control circuit power. Make all control circuit connections between the furnace (or modular blower) and the outdoor unit as specified by the manufacturer's installation instructions. Measure power supplied to both the furnace (or modular blower) and power supplied to the outdoor unit. Alternatively, provide a compatible transformer to supply low-voltage control circuit power, as described in section 2.2.d of this appendix. Measure transformer power, either supplied to the primary winding or supplied by the secondary winding of the transformer, and power supplied to the outdoor unit. For blower coil and single-package systems, make all control circuit connections between components as specified by the manufacturer's installation instructions, and provide power and measure power supplied to all system components.
b. Configure Controls: Configure the controls of the central air conditioner or heat pump so that it operates as if connected to a building thermostat that is set to the OFF position. Use a compatible building thermostat if necessary to achieve this configuration. For a thermostat-controlled crankcase heater with a fixed power input, bypass the crankcase heater thermostat if necessary to energize the heater.
c. Measure P2x: If the unit has a crankcase heater time delay, make sure that time-delay function is disabled or wait until delay time has passed. Determine the average power from non-zero value data measured over a 5-minute interval of the non-operating central air conditioner or heat pump and designate the average power as P2x, the heating season total off mode power.
d. Measure Px for coil-only split systems and for blower coil split systems for which a furnace or a modular blower is the designated air mover: Disconnect all low-voltage wiring for the outdoor components and outdoor controls from the low-voltage transformer. Determine the average power from non-zero value data measured over a 5-minute interval of the power supplied to the (remaining) low-voltage components of the central air conditioner or heat pump, or low-voltage power, Px. This power measurement does not include line power supplied to the outdoor unit. It is the line power supplied to the air mover, or, if a compatible transformer is used instead of an air mover, it is the line power supplied to the transformer primary coil. If a compatible transformer is used instead of an air mover and power output of the low-voltage secondary circuit is measured, Px is zero.
e. Calculate P2: Set the number of compressors equal to the unit's number of single-stage compressors plus 1.75 times the unit's number of compressors that are not single-stage.
For single-package systems and blower coil split systems for which the designated air mover is not a furnace or modular blower, divide the heating season total off mode power (P2x) by the number of compressors to calculate P2, the heating season per-compressor off mode power. Round P2 to the nearest watt. The expression for calculating P2 is as follows:
For coil-only split systems and blower coil split systems for which a furnace or a modular blower is the designated air mover, subtract the low-voltage power (Px) from the heating season total off mode power (Px) and divide by the number of compressors to calculate P2, the heating season per-compressor off mode power. Round P2 to the nearest watt. The expression for calculating P2 is as follows:
f. Shoulder-season per-compressor off mode power, P1: If the system does not have a crankcase heater, has a crankcase heater without controls that is not self-regulating, or has a value for the crankcase heater turn-on temperature (as certified to DOE) that is higher than 71 °F, P1 is equal to P2.
Otherwise, de-energize the crankcase heater (by removing the thermostat bypass or otherwise disconnecting only the power supply to the crankcase heater) and repeat the measurement as described in section 3.13.1.c of this appendix. Designate the measured average power as P1x, the shoulder season total off mode power.
Determine the number of compressors as described in section 3.13.1.e of this appendix.
For single-package systems and blower coil systems for which the designated air mover is not a furnace or modular blower, divide the shoulder season total off mode power (P1x) by the number of compressors to calculate P1, the shoulder season per-compressor off mode power. Round P1 to the nearest watt. The expression for calculating P1 is as follows:
For coil-only split systems and blower coil split systems for which a furnace or a modular blower is the designated air mover, subtract the low-voltage power (Px) from the shoulder season total off mode power (P1x) and divide by the number of compressors to calculate P1, the shoulder season per-compressor off mode power. Round P1 to the nearest watt. The expression for calculating P1 is as follows:
3.13.2 This Test Determines the Off Mode Average Power Rating for Central Air Conditioners and Heat Pumps for Which Ambient Temperature Can Affect the Measurement of Crankcase Heater Powera. Test Sample Set-up and Power Measurement: set up the test and measurement as described in section 3.13.1.a of this appendix.
b. Configure Controls: Position a temperature sensor to measure the outdoor dry-bulb temperature in the air between 2 and 6 inches from the crankcase heater control temperature sensor or, if no such temperature sensor exists, position it in the air between 2 and 6 inches from the crankcase heater. Utilize the temperature measurements from this sensor for this portion of the test procedure. Configure the controls of the central air conditioner or heat pump so that it operates as if connected to a building thermostat that is set to the OFF position. Use a compatible building thermostat if necessary to achieve this configuration.
Conduct the test after completion of the B, B1, or B2 test. Alternatively, start the test when the outdoor dry-bulb temperature is at 82 °F and the temperature of the compressor shell (or temperature of each compressor's shell if there is more than one compressor) is at least 81 °F. Then adjust the outdoor temperature and achieve an outdoor dry-bulb temperature of 72 °F. If the unit's compressor has no sound blanket, wait at least 4 hours after the outdoor temperature reaches 72 °F. Otherwise, wait at least 8 hours after the outdoor temperature reaches 72 °F. Maintain this temperature within ±2 °F while the compressor temperature equilibrates and while making the power measurement, as described in section 3.13.2.c of this appendix.
c. Measure P1x: If the unit has a crankcase heater time delay, make sure that time-delay function is disabled or wait until delay time has passed. Determine the average power from non-zero value data measured over a 5-minute interval of the non-operating central air conditioner or heat pump and designate the average power as P1x, the shoulder season total off mode power. For units with crankcase heaters which operate during this part of the test and whose controls cycle or vary crankcase heater power over time, the test period shall consist of three complete crankcase heater cycles or 18 hours, whichever comes first. Designate the average power over the test period as P1x, the shoulder season total off mode power.
d. Reduce outdoor temperature: Approach the target outdoor dry-bulb temperature by adjusting the outdoor temperature. This target temperature is five degrees Fahrenheit less than the temperature certified by the manufacturer as the temperature at which the crankcase heater turns on. If the unit's compressor has no sound blanket, wait at least 4 hours after the outdoor temperature reaches the target temperature. Otherwise, wait at least 8 hours after the outdoor temperature reaches the target temperature. Maintain the target temperature within ±2 °F while the compressor temperature equilibrates and while making the power measurement, as described in section 3.13.2.e of this appendix.
e. Measure P2x: If the unit has a crankcase heater time delay, make sure that time-delay function is disabled or wait until delay time has passed. Determine the average non-zero power of the non-operating central air conditioner or heat pump over a 5-minute interval and designate it as P2x, the heating season total off mode power. For units with crankcase heaters whose controls cycle or vary crankcase heater power over time, the test period shall consist of three complete crankcase heater cycles or 18 hours, whichever comes first. Designate the average power over the test period as P2x, the heating season total off mode power.
f. Measure Px for coil-only split systems and for blower coil split systems for which a furnace or modular blower is the designated air mover: Disconnect all low-voltage wiring for the outdoor components and outdoor controls from the low-voltage transformer. Determine the average power from non-zero value data measured over a 5-minute interval of the power supplied to the (remaining) low-voltage components of the central air conditioner or heat pump, or low-voltage power, Px. This power measurement does not include line power supplied to the outdoor unit. It is the line power supplied to the air mover, or, if a compatible transformer is used instead of an air mover, it is the line power supplied to the transformer primary coil. If a compatible transformer is used instead of an air mover and power output of the low-voltage secondary circuit is measured, Px is zero.
g. Calculate P1:
Set the number of compressors equal to the unit's number of single-stage compressors plus 1.75 times the unit's number of compressors that are not single-stage.
For single-package systems and blower coil split systems for which the air mover is not a furnace or modular blower, divide the shoulder season total off mode power (P1x) by the number of compressors to calculate P1, the shoulder season per-compressor off mode power. Round to the nearest watt. The expression for calculating P1 is as follows:
For coil-only split systems and blower coil split systems for which a furnace or a modular blower is the designated air mover, subtract the low-voltage power (Px) from the shoulder season total off mode power (P1x) and divide by the number of compressors to calculate P1, the shoulder season per-compressor off mode power. Round to the nearest watt. The expression for calculating P1 is as follows:
h. Calculate P2:
Determine the number of compressors as described in section 3.13.2.g of this appendix.
For, single-package systems and blower coil split systems for which the air mover is not a furnace, divide the heating season total off mode power (P2x) by the number of compressors to calculate P2, the heating season per-compressor off mode power. Round to the nearest watt. The expression for calculating P2 is as follows:
For coil-only split systems and blower coil split systems for which a furnace or a modular blower is the designated air mover, subtract the low-voltage power (Px) from the heating season total off mode power (P2x) and divide by the number of compressors to calculate P2, the heating season per-compressor off mode power. Round to the nearest watt. The expression for calculating P2 is as follows:
4 Calculations of Seasonal Performance Descriptors 4.1 Seasonal Energy Efficiency Ratio (SEER2) CalculationsCalculate SEER2 as follows: For equipment covered under sections 4.1.2, 4.1.3, and 4.1.4 of this appendix, evaluate the seasonal energy efficiency ratio,
where,
Tj = the
outdoor bin temperature, °F. Outdoor temperatures are grouped or
“binned.” Use bins of 5 °F with the 8 cooling season bin
temperatures being 67, 72, 77, 82, 87, 92, 97, and 102 °F. j = the
bin number. For cooling season calculations, j ranges from 1 to 8.
Additionally, for sections 4.1.2, 4.1.3, and 4.1.4 of this appendix, use a building cooling load, BL(Tj). When referenced, evaluate BL(Tj) for cooling using,
where: Q
ck=2(95) = the space cooling capacity determined from the A2 test
and calculated as specified in section 3.3 of this appendix, Btu/h.
1.1 = sizing factor, dimensionless. The temperatures 95 °F and 65
°F in the building load equation represent the selected outdoor
design temperature and the zero-load base temperature,
respectively. V is a factor equal to 0.93 for variable-speed heat
pumps and otherwise equal to 1.0. 4.1.1 SEER2 Calculations for a
Blower Coil System Having a Single-Speed Compressor and Either a
Fixed-Speed Indoor Blower or a Constant-Air-Volume-Rate Indoor
Blower, or a Single-Speed Coil-Only System Air Conditioner or Heat
Pump
a. Evaluate the seasonal energy efficiency ratio, expressed in units of Btu/watt-hour, using:
SEER2 = PLF(0.5) * EERB
where:
PLF(0.5) = 1 − 0.5 · CD c, the part-load performance factor
evaluated at a cooling load factor of 0.5, dimensionless.
b. Refer to section 3.3 of this appendix regarding the definition and calculation of Q c(82) and E c(82). Evaluate the cooling mode cyclic degradation factor CD c as specified in section 3.5.3 of this appendix.
4.1.2 SEER2 Calculations for an Air Conditioner or Heat Pump Having a Single-Speed Compressor and a Variable-Speed Variable-Air-Volume-Rate Indoor Blower 4.1.2.1 Units Covered by Section 3.2.2.1 of This Appendix Where Indoor Blower Capacity Modulation Correlates With the Outdoor Dry Bulb TemperatureThe manufacturer must provide information on how the indoor air volume rate or the indoor blower speed varies over the outdoor temperature range of 67 °F to 102 °F. Calculate SEER2 using Equation 4.1-1. Evaluate the quantity qc(Tj)/N in Equation 4.1-1 using,
where:
Q c(Tj) =
the space cooling capacity of the test unit when operating at
outdoor temperature, Tj, Btu/h. nj/N = fractional bin hours for the
cooling season; the ratio of the number of hours during the cooling
season when the outdoor temperature fell within the range
represented by bin temperature Tj to the total number of hours in
the cooling season, dimensionless.
a. For the space cooling season, assign nj/N as specified in Table 19. Use Equation 4.1-2 to calculate the building load, BL(Tj). Evaluate Q c(Tj) using,
where:
the space
cooling capacity of the test unit at outdoor temperature Tj if
operated at the cooling minimum air volume rate, Btu/h. 
the space cooling
capacity of the test unit at outdoor temperature Tj if operated at
the Cooling full-load air volume rate, Btu/h.
b. For units where indoor blower speed is the primary control variable, FPck=1 denotes the fan speed used during the required A1 and B1 tests (see section 3.2.2.1 of this appendix), FPck=2 denotes the fan speed used during the required A2 and B2 tests, and FPc(Tj) denotes the fan speed used by the unit when the outdoor temperature equals Tj. For units where indoor air volume rate is the primary control variable, the three FPc's are similarly defined only now being expressed in terms of air volume rates rather than fan speeds. Refer to sections 3.2.2.1, 3.1.4 to 3.1.4.2, and 3.3 of this appendix regarding the definitions and calculations of Q ck=1(82), Q ck=1(95),Q c k=2(82), and Q ck=2(95).
Calculate ec(Tj)/N in Equation 4.1-1 using, Equation 4.1.2-3
where:
PLFj = 1 − CD c · [1 − X(Tj)], the part load factor, dimensionless.
E c(Tj) = the electrical power consumption of the test unit when
operating at outdoor temperature Tj, W.
c. The quantities X(Tj) and nj/N are the same quantities as used in Equation 4.1.2-1. Evaluate the cooling mode cyclic degradation factor CD c as specified in section 3.5.3 of this appendix.
d. Evaluate E c(Tj) using,
the
electrical power consumption of the test unit at outdoor
temperature Tj if operated at the cooling minimum air volume rate,
W. 
e. The parameters FPck=1, and FPck=2, and FPc(Tj) are the same quantities that are used when evaluating Equation 4.1.2-2. Refer to sections 3.2.2.1, 3.1.4 to 3.1.4.2, and 3.3 of this appendix regarding the definitions and calculations of E ck=1(82), E ck=1(95), E ck=2(82), and E ck=2(95).
4.1.2.2 Units Covered by Section 3.2.2.2 of This Appendix Where Indoor Blower Capacity Modulation is Used to Adjust the Sensible to Total Cooling Capacity RatioCalculate SEER2 as specified in section 4.1.1 of this appendix.
4.1.3 SEER2 Calculations for an Air Conditioner or Heat Pump Having a Two-Capacity CompressorCalculate SEER2 using Equation 4.1-1. Evaluate the space cooling capacity, Q ck=1 (Tj), and electrical power consumption, E ck=1 (Tj), of the test unit when operating at low compressor capacity and outdoor temperature Tj using,
where Q ck=1 (82)
and E ck=1 (82) are determined from the B1 test, Q ck=1 (67) and E
ck=1 (67) are determined from the F1 test, and all four quantities
are calculated as specified in section 3.3 of this appendix.
Evaluate the space cooling capacity, Q ck=2 (Tj), and electrical
power consumption, E ck=2 (Tj), of the test unit when operating at
high compressor capacity and outdoor temperature Tj using,
where Q ck=2(95)
and E ck=2(95) are determined from the A2 test, Q ck=2(82), and E
ck=2(82), are determined from the B2 test, and all are calculated
as specified in section 3.3 of this appendix.
The calculation of Equation 4.1-1 quantities qc(Tj)/N and ec(Tj)/N differs depending on whether the test unit would operate at low capacity (section 4.1.3.1 of this appendix), cycle between low and high capacity (section 4.1.3.2 of this appendix), or operate at high capacity (sections 4.1.3.3 and 4.1.3.4 of this appendix) in responding to the building load. For units that lock out low capacity operation at higher outdoor temperatures, the outdoor temperature at which the unit locks out must be that specified by the manufacturer in the certification report so that the appropriate equations are used. Use Equation 4.1-2 to calculate the building load, BL(Tj), for each temperature bin.
4.1.3.1 Steady-state Space Cooling Capacity at Low Compressor Capacity Is Greater Than or Equal to the Building Cooling Load at Temperature Tj, Q ck=1(Tj) ≥BL(Tj)
Where: Xk=1(Tj) =
BL(Tj)/Q ck=1(Tj), the cooling mode low capacity load factor for
temperature bin j, dimensionless. PLFj = 1 − CD c · [1 − Xk=1(Tj)],
the part load factor, dimensionless.
nj/N = fractional bin hours for the cooling season; the ratio of the number of hours during the cooling season when the outdoor temperature fell within the range represented by bin temperature Tj to the total number of hours in the cooling season, dimensionless.
Obtain the fractional bin hours for the cooling season, nj/N, from Table 19. Use Equations 4.1.3-1 and 4.1.3-2, respectively, to evaluate Q ck=1(Tj) and E ck=1(Tj). Evaluate the cooling mode cyclic degradation factor CD c as specified in section 3.5.3 of this appendix.
Table 19 - Distribution of Fractional Hours Within Cooling Season Temperature Bins
| Bin number, j | Bin temperature range °F | Representative temperature for bin °F | Fraction of of total temperature bin hours, nj/N |
|---|---|---|---|
| 1 | 65-69 | 67 | 0.214 |
| 2 | 70-74 | 72 | 0.231 |
| 3 | 75-79 | 77 | 0.216 |
| 4 | 80-84 | 82 | 0.161 |
| 5 | 85-89 | 87 | 0.104 |
| 6 | 90-94 | 92 | 0.052 |
| 7 | 95-99 | 97 | 0.018 |
| 8 | 100-104 | 102 | 0.004 |
Where: 
Xk=2(Tj) = 1 − Xk=1(Tj), the cooling mode, high capacity load factor for temperature bin j, dimensionless.
Obtain the fractional bin hours for the cooling season, nj/N, from Table 19. Use Equations 4.1.3-1 and 4.1.3-2, respectively, to evaluate Q ck=1(Tj) and E ck=1(Tj). Use Equations 4.1.3-3 and 4.1.3-4, respectively, to evaluate Q ck=2(Tj) and E ck=2(Tj).
4.1.3.3 Unit Only Operates at High (k=2) Compressor Capacity at Temperature Tj and Its Capacity Is Greater Than the Building Cooling Load, BL(Tj) <Q ck=2(Tj). This section applies to units that lock out low compressor capacity operation at higher outdoor temperatures.
Where,
Xk=2(Tj) = BL(Tj)/Q ck=2(Tj), the cooling mode high capacity load factor for temperature bin j, dimensionless.
PLFj = 1−CDc(k = 2) * [1−Xk=2(Tj)], the part load factor, dimensionless.Obtain the fractional bin hours for the cooling season, nj/N, from Table 19. Use Equations 4.1.3-3 and 4.1.3-4, respectively, to evaluate Q ck=2 (Tj) and E ck=2 (Tj). If the C2 and D2 tests described in section 3.2.3 and Table 7 of this appendix are not conducted, set CD c (k=2) equal to the default value specified in section 3.5.3 of this appendix.
4.1.3.4 Unit Must Operate Continuously at High (k=2) Compressor Capacity at Temperature Tj, BL(Tj) ≥Q ck=2(Tj)
Obtain the
fractional bin hours for the cooling season, nj/N, from Table 19.
Use Equations 4.1.3-3 and 4.1.3-4, respectively, to evaluate Q
ck=2(Tj) and E ck=2(Tj). 4.1.4 SEER2 Calculations for an Air
Conditioner or Heat Pump Having a Variable-Speed Compressor
Calculate SEER2 using Equation 4.1-1. Evaluate the space cooling capacity, Q ck=1(Tj), and electrical power consumption, E ck=1(Tj), of the test unit when operating at minimum compressor speed and outdoor temperature Tj. Use,
where Q ck=1(82)
and E ck=1(82) are determined from the B1 test, Q ck=1(67) and E
ck=1(67) are determined from the F1 test, and all four quantities
are calculated as specified in section 3.3 of this appendix.
Evaluate the space cooling capacity, Q ck=2(Tj), and electrical
power consumption, E ck=2(Tj), of the test unit when operating at
full compressor speed and outdoor temperature Tj. Use Equations
4.1.3-3 and 4.1.3-4, respectively, where Q ck=2(95) and E ck=2(95)
are determined from the A2 test, Q ck=2(82) and E ck=2(82) are
determined from the B2 test, and all four quantities are calculated
as specified in section 3.3 of this appendix. Calculate the space
cooling capacity, Q ck=v(Tj), and electrical power consumption, E
ck=v(Tj), of the test unit when operating at outdoor temperature Tj
and the intermediate compressor speed used during the section 3.2.4
(and Table 8) EV test of this appendix using, 
where Q ck=v(87)
and E ck=v(87) are determined from the EV test and calculated as
specified in section 3.3 of this appendix. Approximate the slopes
of the k=v intermediate speed cooling capacity and electrical power
input curves, MQ and ME, as follows: 
Use Equations 4.1.4-1 and 4.1.4-2, respectively, to calculate Q ck=1(87) and E ck=1(87).
4.1.4.1 Steady-state space cooling capacity when operating at minimum compressor speed is greater than or equal to the building cooling load at temperature Tj, Q ck=1(Tj) ≥BL(Tj).
Where:
Xk=1(Tj) = BL(Tj)/Q ck=1(Tj), the cooling mode minimum speed load
factor for temperature bin j, dimensionless. PLFj = 1 − CD c · [1 −
Xk=1(Tj)], the part load factor, dimensionless. nj/N = fractional
bin hours for the cooling season; the ratio of the number of hours
during the cooling season when the outdoor temperature fell within
the range represented by bin temperature Tj to the total number of
hours in the cooling season, dimensionless.
Obtain the fractional bin hours for the cooling season, nj/N, from Table 19. Use Equations 4.1.3-1 and 4.1.3-2, respectively, to evaluate Q c k=l (Tj) and E c k=l (Tj). Evaluate the cooling mode cyclic degradation factor CD c as specified in section 3.5.3 of this appendix.
4.1.4.2 Unit operates at an intermediate compressor speed (k=i) in order to match the building cooling load at temperature Tj, Q ck=1(Tj) <BL(Tj) <Q ck=2(Tj).
Where: Q
ck=i(Tj) = BL(Tj), the space cooling capacity delivered by the unit
in matching the building load at temperature Tj, Btu/h. The
matching occurs with the unit operating at compressor speed k = i.
EERk=i(Tj) = the steady-state energy efficiency ratio of the test
unit when operating at a compressor speed of k = i and temperature
Tj, Btu/h per W.
Obtain the fractional bin hours for the cooling season, nj/N, from Table 19 of this section. For each temperature bin where the unit operates at an intermediate compressor speed, determine the energy efficiency ratio EERk=i(Tj) using the following equations,
For each temperature bin where Q ck=1(Tj) <BL(Tj) <Q ck=v(Tj),
For each temperature bin where Q ck=v(Tj) ≤BL(Tj) <Q ck=2(Tj),
Where:
EERk=1(Tj) is the steady-state energy efficiency ratio of the test unit when operating at minimum compressor speed and temperature Tj, Btu/h per W, calculated using capacity Q ck=1(Tj) calculated using Equation 4.1.4-1 and electrical power consumption E ck=1(Tj) calculated using Equation 4.1.4-2;
EERk=v(Tj) is the steady-state energy efficiency ratio of the test unit when operating at intermediate compressor speed and temperature Tj, Btu/h per W, calculated using capacity Q ck=v(Tj) calculated using Equation 4.1.4-3 and electrical power consumption E ck=v(Tj) calculated using Equation 4.1.4-4;
EER2k=2(Tj) is the steady-state energy efficiency ratio of the test unit when operating at full compressor speed and temperature Tj, Btu/h per W, calculated using capacity Q ck=2(Tj) and electrical power consumption E ck=2(Tj), both calculated as described in section 4.1.4; and
BL(Tj) is the building cooling load at temperature Tj, Btu/h.
4.1.4.3 Unit must operate continuously at full (k=2) compressor speed at temperature Tj, BL(Tj) ≥Q ck=2(Tj). Evaluate the Equation 4.1-1 quantities
as
specified in section 4.1.3.4 of this appendix with the
understanding that Q ck=2(Tj) and E ck=2(Tj) correspond to full
compressor speed operation and are derived from the results of the
tests specified in section 3.2.4 of this appendix. 4.1.5 SEER2
Calculations for an Air Conditioner or Heat Pump Having a Single
Indoor Unit With Multiple Indoor Blowers
Calculate SEER2 using Eq. 4.1-1, where qc(Tj)/N and ec(Tj)/N are evaluated as specified in the applicable subsection.
4.1.5.1 For Multiple Indoor Blower Systems That Are Connected to a Single, Single-Speed Outdoor Unita. Calculate the space cooling capacity, Q ck=1(Tj), and electrical power consumption, E ck=1(Tj), of the test unit when operating at the cooling minimum air volume rate and outdoor temperature Tj using the equations given in section 4.1.2.1 of this appendix. Calculate the space cooling capacity, Q ck=2(Tj), and electrical power consumption, E ck=2(Tj), of the test unit when operating at the cooling full-load air volume rate and outdoor temperature Tj using the equations given in section 4.1.2.1 of this appendix. In evaluating the section 4.1.2.1 equations, determine the quantities Q ck=1(82) and E ck=1(82) from the B1 test, Q ck=1(95) and E ck=1(95) from the Al test, Q ck=2(82) and E ck=2(82) from the B2 test, and Q ck=2(95) and E ck=2(95) from the A2 test. Evaluate all eight quantities as specified in section 3.3. Refer to section 3.2.2.1 and Table 6 for additional information on the four referenced laboratory tests.
b. Determine the cooling mode cyclic degradation coefficient, CD c, as per sections 3.2.2.1 and 3.5 to 3.5.3 of this appendix. Assign this same value to CD c(K=2).
c. Except for using the above values of Q ck=1(Tj), E ck=1(Tj), E ck=2(Tj), Q ck=2(Tj), CD c, and CD c (K=2), calculate the quantities qc(Tj)/N and ec(Tj)/N as specified in section 4.1.3.1 of this appendix for cases where Q ck=1(Tj) ≥ BL(Tj). For all other outdoor bin temperatures, Tj, calculate qc(Tj)/N and ec(Tj)/N as specified in section 4.1.3.3 of this appendix if Q ck=2(Tj) > BL (Tj) or as specified in section 4.1.3.4 of this appendix if Q ck=2(Tj) ≤ BL(Tj).
4.1.5.2 For Multiple Indoor Blower Systems That Are Connected to Either a Lone Outdoor Unit Having a Two-Capacity Compressor or Two Separate But Identical Model Single-Speed Outdoor Units. Calculate the Quantities qc(Tj)/N and ec(Tj)/N as Specified in Section 4.1.3 of This Appendix 4.2 Heating Seasonal Performance Factor 2 (HSPF2) CalculationsUnless an approved alternative efficiency determination method is used, as set forth in 10 CFR 429.70(e). Calculate HSPF2 as follows: Six generalized climatic regions are depicted in Figure 1 and otherwise defined in Table 20. For each of these regions and for each applicable standardized design heating requirement, evaluate the heating seasonal performance factor using,
Where:
eh(Tj)/N = The ratio of the electrical energy consumed by the heat
pump during periods of the heating season when the outdoor
temperature fell within the range represented by bin temperature Tj
to the total number of hours in the heating season (N), W. For heat
pumps having a heat comfort controller, this ratio may also include
electrical energy used by resistive elements to maintain a minimum
air delivery temperature (see 4.2.5). RH(Tj)/N = The ratio of the
electrical energy used for resistive space heating during periods
when the outdoor temperature fell within the range represented by
bin temperature Tj to the total number of hours in the heating
season (N), W. Except as noted in section 4.2.5 of this appendix,
resistive space heating is modeled as being used to meet that
portion of the building load that the heat pump does not meet
because of insufficient capacity or because the heat pump
automatically turns off at the lowest outdoor temperatures. For
heat pumps having a heat comfort controller, all or part of the
electrical energy used by resistive heaters at a particular bin
temperature may be reflected in eh(Tj)/N (see section 4.2.5 of this
appendix). Tj = the outdoor bin temperature, °F. Outdoor
temperatures are “binned” such that calculations are only performed
based one temperature within the bin. Bins of 5 °F are used. nj/N =
Fractional bin hours for the heating season; the ratio of the
number of hours during the heating season when the outdoor
temperature fell within the range represented by bin temperature Tj
to the total number of hours in the heating season, dimensionless.
Obtain nj/N values from Table 20. j = the bin number,
dimensionless. J = for each generalized climatic region, the total
number of temperature bins, dimensionless. Referring to Table 20, J
is the highest bin number (j) having a nonzero entry for the
fractional bin hours for the generalized climatic region of
interest. Fdef = the demand defrost credit described in section
3.9.2 of this appendix, dimensionless. BL(Tj) = the building space
conditioning load corresponding to an outdoor temperature of Tj;
the heating season building load also depends on the generalized
climatic region's outdoor design temperature and the design heating
requirement, Btu/h.
Table 20 - Generalized Climatic Region Information
| Region Number | I | II | III | IV | V | * VI |
|---|---|---|---|---|---|---|
| Heating Load Hours, HLH | 493 | 857 | 1247 | 1701 | 2202 | 1842 |
| Outdoor Design Temperature, TOD | 37 | 27 | 17 | 5 | −10 | 30 |
| Heating Load Line Equation Slope Factor, C | 1.10 | 1.06 | 1.30 | 1.15 | 1.16 | 1.11 |
| Variable-speed Slope Factor, CVS | 1.03 | 0.99 | 1.21 | 1.07 | 1.08 | 1.03 |
| Zero-Load Temperature, Tzl | 58 | 57 | 56 | 55 | 55 | 57 |
| j Tj ( °F) | Fractional Bin Hours, nj/N | |||||
| 1 62 | 0 | 0 | 0 | 0 | 0 | 0 |
| 2 57 | .239 | 0 | 0 | 0 | 0 | 0 |
| 3 52 | .194 | .163 | .138 | .103 | .086 | .215 |
| 4 47 | .129 | .143 | .137 | .093 | .076 | .204 |
| 5 42 | .081 | .112 | .135 | .100 | .078 | .141 |
| 6 37 | .041 | .088 | .118 | .109 | .087 | .076 |
| 7 32 | .019 | .056 | .092 | .126 | .102 | .034 |
| 8 27 | .005 | .024 | .047 | .087 | .094 | .008 |
| 9 22 | .001 | .008 | .021 | .055 | .074 | .003 |
| 10 17 | 0 | .002 | .009 | .036 | .055 | 0 |
| 11 12 | 0 | 0 | .005 | .026 | .047 | 0 |
| 12 7 | 0 | 0 | .002 | .013 | .038 | 0 |
| 13 2 | 0 | 0 | .001 | .006 | .029 | 0 |
| 14 −3 | 0 | 0 | 0 | .002 | .018 | 0 |
| 15 −8 | 0 | 0 | 0 | .001 | .010 | 0 |
| 16 −13 | 0 | 0 | 0 | 0 | .005 | 0 |
| 17 −18 | 0 | 0 | 0 | 0 | .002 | 0 |
| 18 −23 | 0 | 0 | 0 | 0 | .001 | 0 |
* Pacific Coast Region.
Evaluate the building heating load using
where, Tj
= the outdoor bin temperature, °F Tzl = the zero-load temperature,
°F, which varies by climate region according to Table 20 C = the
slope (adjustment) factor, which varies by climate region according
to Table 20 Q c(95°F) = the cooling capacity at 95 °F
determined from the A or A2 test,Btu/h For heating-only heat pump
units, replace Q c(95°F) in Equation 4.2-2 with
Q h(47°F) Q h(47°F)= the heating
capacity at 47 °F determined from the H, H12 or H1N test, Btu/h.
a. For all heat pumps, HSPF2 accounts for the heating delivered and the energy consumed by auxiliary resistive elements when operating below the balance point. This condition occurs when the building load exceeds the space heating capacity of the heat pump condenser. For HSPF2 calculations for all heat pumps, see either section 4.2.1, 4.2.2, 4.2.3, or 4.2.4 of this appendix, whichever applies.
b. For heat pumps with heat comfort controllers (see section 1.2 of this appendix, Definitions), HSPF2 also accounts for resistive heating contributed when operating above the heat-pump-plus-comfort-controller balance point as a result of maintaining a minimum supply temperature. For heat pumps having a heat comfort controller, see section 4.2.5 of this appendix for the additional steps required for calculating the HSPF2.
4.2.1 Additional Steps for Calculating the HSPF2 of a Blower Coil System Heat Pump Having a Single-Speed Compressor and Either a Fixed-Speed Indoor Blower or a Constant-Air-Volume-Rate Indoor Blower, or a Single-Speed Coil-Only System Heat Pump
Where: 
whichever is less;
the heating mode load factor for temperature bin j, dimensionless.
Q h(Tj) = the space heating capacity of the heat pump when
operating at outdoor temperature Tj, Btu/h. E h(Tj) = the
electrical power consumption of the heat pump when operating at
outdoor temperature Tj, W. δ(Tj) = the heat pump low temperature
cut-out factor, dimensionless. PLFj = 1 − C Dh · [1 −X(Tj)] the
part load factor, dimensionless.
Use Equation 4.2-2 to determine BL(Tj). Obtain fractional bin hours for the heating season, nj/N, from Table 20. Evaluate the heating mode cyclic degradation factor CDh as specified in section 3.8.1 of this appendix.
Determine the low temperature cut-out factor using
Where:
Toff = the outdoor temperature when the compressor is automatically
shut off, °F. (If no such temperature exists, Tj is always greater
than Toff and Ton).
Ton = the outdoor temperature when the compressor is automatically turned back on, if applicable, following an automatic shut-off, °F.
If the H4 test is not conducted, calculate Qh(Tj) and Eh(Tj) using
where Q h(47) and
E h(47) are determined from the H1 test and calculated as specified
in section 3.7 of this appendix; Q h(35) and E h(35) are determined
from the H2 test and calculated as specified in section 3.9.1 of
this appendix; and Q h(17) and E h(17) are determined from the H3
test and calculated as specified in section 3.10 of this appendix.
If the H4 test is conducted, calculate Q h(Tj) and E h(Tj) using
where Q h(47) and
E h(47) are determined from the H1 test and calculated as specified
in section 3.7 of this appendix; Q h(35) and E h(35) are determined
from the H2 test and calculated as specified in section 3.9.1 of
this appendix; Q h(17) and E h(17) are determined from the H3 test
and calculated as specified in section 3.10 of this appendix; Q
h(5) and E h(5) are determined from the H4 test and calculated as
specified in section 3.10 of this appendix. 4.2.2 Additional Steps
for Calculating the HSPF2 of a Heat Pump Having a Single-Speed
Compressor and a Variable-Speed, Variable-Air-Volume-Rate Indoor
Blower
The manufacturer must provide information about how the indoor air volume rate or the indoor blower speed varies over the outdoor temperature range of 65 °F to −23 °F. Calculate the quantities
in
Equation 4.2-1 as specified in section 4.2.1 of this appendix with
the exception of replacing references to the H1C test and section
3.6.1 of this appendix with the H1C1 test and section 3.6.2 of this
appendix. In addition, evaluate the space heating capacity and
electrical power consumption of the heat pump Q h(Tj) and E h(Tj)
using 
where the
space heating capacity and electrical power consumption at low
capacity (k=1) at outdoor temperature Tj are determined using
If the H42 test is not conducted, calculate the space heating capacity and electrical power consumption at high capacity (k=2) at outdoor temperature Tj using Equations 4.2.2-3 and 4.2.2-4 for k=2.
If the H42 test is conducted, calculate the space heating capacity and electrical power consumption at high capacity (k=2) at outdoor temperature Tj using Equations 4.2.2-5 and 4.2.2-6.
For units where indoor blower speed is the primary control variable, FPhk=1 denotes the fan speed used during the required H11 and H31 tests (see Table 12), FPhk=2 denotes the fan speed used during the required H12, H22, and H32 tests, and FPh(Tj) denotes the fan speed used by the unit when the outdoor temperature equals Tj. For units where indoor air volume rate is the primary control variable, the three FPh's are similarly defined only now being expressed in terms of air volume rates rather than fan speeds. Determine Q hk=1(47) and E hk=1(47) from the H11 test, and Q hk=2(47) and E hk=2(47) from the H12 test. Calculate all four quantities as specified in section 3.7 of this appendix. Determine Q hk=1(35) and E hk=1(35) as specified in section 3.6.2 of this appendix; determine Q hk=2(35) and E hk=2(35) and from the H22 test and the calculation specified in section 3.9 of this appendix. Determine Q hk=1(17) and E hk=1(17 from the H31 test, and Q hk=2(17) and E hk=2(17) from the H32 test. Calculate all four quantities as specified in section 3.10 of this appendix. Determine Q hk=2(5) and E hk=2(5) from the H42 test and the calculation specified in section 3.10 of this appendix.
4.2.3 Additional Steps for Calculating the HSPF2 of a Heat Pump Having a Two-Capacity CompressorThe calculation of the Equation 4.2-1 quantities differ depending upon whether the heat pump would operate at low capacity (section 4.2.3.1 of this appendix), cycle between low and high capacity (section 4.2.3.2 of this appendix), or operate at high capacity (sections 4.2.3.3 and 4.2.3.4 of this appendix) in responding to the building load. For heat pumps that lock out low capacity operation at low outdoor temperatures, the outdoor temperature at which the unit locks out must be that specified by the manufacturer in the certification report so that the appropriate equations can be selected.
a. Evaluate the space heating capacity and electrical power consumption of the heat pump when operating at low compressor capacity and outdoor temperature Tj using
b. If the H42 test is not conducted, evaluate the space heating capacity and electrical power consumption (Q hk=2(Tj) and E hk=2 (Tj)) of the heat pump when operating at high compressor capacity and outdoor temperature Tj by solving Equations 4.2.2-3 and 4.2.2-4, respectively, for k=2. If the H42 test is conducted, evaluate the space heating capacity and electrical power consumption (Q hk=2(Tj) and E hk=2 (Tj)) of the heat pump when operating at high compressor capacity and outdoor temperature Tj using Equations 4.2.2-5 and 4.2.2-6, respectively.
Determine Q hk=1(62) and E hk=1(62) from the H01 test, Q hk=1(47) and E hk=1(47) from the H11 test, and Q hk=2(47) and E hk=2(47) from the H12 test. Calculate all six quantities as specified in section 3.7 of this appendix. Determine Q hk=2(35) and E hk=2(35) from the H22 test and, if required as described in section 3.6.3 of this appendix, determine Q hk=1(35) and E hk=1(35) from the H21 test. Calculate the required 35 °F quantities as specified in section 3.9 in this appendix. Determine Q hk=2(17) and E hk=2(17) from the H32 test and, if required as described in section 3.6.3 of this appendix, determine Q hk=1(17) and E hk=1(17) from the H31 test. Calculate the required 17 °F quantities as specified in section 3.10 of this appendix. Determine Q hk=2(5) and E hk=2(5) from the H42 test and the calculation specified in section 3.10 of this appendix.
4.2.3.1 Steady-State Space Heating Capacity When Operating at Low Compressor Capacity Is Greater Than or Equal to the Building Heating Load at Temperature Tj, Q hk=1(Tj) ≥BL(Tj)
Where: Xk=1(Tj) =
BL(Tj)/Q hk=1(Tj), the heating mode low capacity load factor for
temperature bin j, dimensionless. PLFj = 1 − CDh · [ 1 −
Xk=1(Tj) ], the part load factor, dimensionless. δ′(Tj) = the low
temperature cutoff factor, dimensionless.
Evaluate the heating mode cyclic degradation factor CDh as specified in section 3.8.1 of this appendix.
Determine the low temperature cut-out factor using
