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(continued)

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 fan motor to within ±1.0 percent. If required according to sections 3.3, 3.4, 3.7, 3.9.1, and/or 3.10, this same instrumentation requirement applies when testing air conditioners and heat pumps having a variable-speed constant-air-volume-rate indoor fan or a variable-speed, variable-air-volume-rate indoor fan.

2.9 Time measurements. Make 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 measurement. For 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. In addition, for all steady-state tests, conduct a second, independent measurement of capacity as described in section 3.1.1. For split systems, use one of the following secondary measurement methods: Outdoor Air Enthalpy Method, Compressor Calibration Method, or Refrigerant Enthalpy Method. For single packaged units, use either the Outdoor Air Enthalpy Method or the Compressor Calibration Method as the secondary measurement.

2.10.1 Outdoor Air Enthalpy Method. a. 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) An outlet plenum containing static pressure taps (sections 2.4, 2.4.1, and 2.5.3),

(2) An airflow measuring apparatus (section 2.6),

(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), and

(4) On the inlet side, a sampling device and optional temperature grid (sections 2.5 and 2.5.2).

c. During the preliminary tests described in sections 3.11.1 and 3.11.1.1, 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, connect pressure gages to the access valves or to ports created from tapping into the suction and discharge lines. 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 Method. Measure 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, measure refrigerant properties, and adjust the refrigerant charge according to section 7.4.2 of ASHRAE Standard 37–88 (incorporated by reference, see §430.22). Use refrigerant temperature and pressure measuring instruments that meet the specifications given in sections 5.1.1 and 5.2 of ASHRAE Standard 37–88 (incorporated by reference, see §430.22).

2.10.3 Refrigerant Enthalpy Method. For 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 7.6.2 of ASHRAE Standard 37–88 (incorporated by reference, see §430.22) 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 ASHRAE Standard 37–88 (incorporated by reference, see §430.22).

2.11 Measurement of test room ambient conditions. 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 ASHRAE Standard 37–88 (incorporated by reference, see §430.22)), add instrumentation to permit measurement of the indoor test room dry-bulb temperature.

b. If the Outdoor Air Enthalpy Method is not used, add instrumentation to measure the dry-bulb temperature and the water vapor content of the air entering the outdoor coil. If an air sampling device is used, construct and apply the device as per section 6 of ASHRAE Standard 41.1–86 (RA 01) (incorporated by reference, see §430.22). Take steps (e.g., add or re-position a lab circulating fan), as needed, to minimize the magnitude of the temperature distribution non-uniformity. Position any fan in the outdoor test room while trying to keep air velocities in the vicinity of the test unit below 500 feet per minute.

c. Measure dry bulb temperatures as specified in sections 4, 5, 6.1–6.10, 9, 10, and 11 of ASHRAE Standard 41.1–86 (RA 01) (incorporated by reference, see §430.22). Measure water vapor content as stated above in section 2.5.6.

2.12 Measurement of indoor fan speed. When 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 pressure. Determine the average barometric pressure during each test. Use an instrument that meets the requirements specified in section 5.2 of ASHRAE Standard 37–88 (incorporated by reference, see §430.22).

3. Testing Procedures

3.1 General Requirements. If, during the testing process, an equipment set-up adjustment is made that would alter the performance of the unit when conducting an 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.

3.1.1 Primary and secondary test methods. For 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 all steady-state tests (i.e., the A, A2, A1, B, B2, B1, C, C1, EV, F1, G1, H01, H1, H12, H11, HIN, H3, H32, and H31 Tests), in addition, use one of the acceptable secondary methods specified in section 2.10 to determine indoor space conditioning capacity. Calculate this secondary check of capacity according to section 3.11. 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 ASHRAE Standard 37–88 (incorporated by reference, see §430.22) (and do not make the after-test fan heat adjustments described in sections 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.

3.1.2 Manufacturer-provided equipment overrides. Where 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 fan operates at the specified speed or delivers the specified air volume rate.

3.1.3 Airflow through the outdoor coil. For all tests, meet the requirements given in section 6.1.3.4 of ARI Standard 210/240–2003 (incorporated by reference, see §430.22) when obtaining the airflow through the outdoor coil.

3.1.4 Airflow through the indoor coil.

3.1.4.1 Cooling Certified Air Volume Rate.

3.1.4.1.1 Cooling Certified Air Volume Rate for Ducted Units. The manufacturer must specify the Cooling Certified Air Volume Rate. Use this value as long as the following two requirements are satisfied. First, when conducting the A or A2 Test (exclusively), the measured air volume rate, when divided by the measured indoor air-side total cooling capacity, must not exceed 37.5 cubic feet per minute of standard air (scfm) per 1000 Btu/h. If this ratio is exceeded, reduce the air volume rate until this ratio is equaled. Use this reduced air volume rate for all tests that call for using the Cooling Certified Air Volume Rate. The second requirement is as follows:

a. For ducted units that are tested with a fixed-speed, multi-speed, or variable-speed variable-air-volume-rate indoor fan installed. For the A or A2 Test (exclusively), the measured external static pressure must be equal to or greater than the applicable minimum external static pressure cited in Table 2. If the Table 2 minimum is not equaled or exceeded, incrementally change the set-up of the indoor fan (e.g., fan motor pin settings, fan motor speed) until the Table 2 requirement is met while maintaining the same air volume rate. If the indoor fan set-up changes cannot provide the minimum external static, then reduce the air volume rate until the correct Table 2 minimum is equaled. For the last scenario, use the reduced air volume rate for all tests that require the Cooling Certified Air Volume Rate.

b. For ducted units that are tested with a constant-air-volume-rate indoor fan installed. For all tests that specify the Cooling Certified Air Volume Rate, obtain an external static pressure as close to (but not less than) the applicable Table 2 value that does not cause instability or an automatic shutdown of the indoor blower.

c. For ducted units that are tested without an indoor fan installed. 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 Certified Air Volume Rate.


Table 2_Minimum External Static Pressure for Ducted Systems Tested With
an Indoor Fan Installed
------------------------------------------------------------------------
Rated Cooling \1\ or Heating \2\ Minimum External Resistance \3\
Capacity (Btu/h) (Inches of Water)
------------------------------------------------------------------------
Up Thru 28,800........................ 0.10
29,000 to 42,500...................... 0.15
43,000 and Above...................... 0.20
------------------------------------------------------------------------
\1\ For air conditioners and heat pumps, the value cited by the
manufacturer in published literature for the unit's capacity when
operated at the A or A2 Test conditions.
\2\ For heating-only heat pumps, the value the manufacturer cites in
published literature for the unit's capacity when operated at the H1
or H12 Test conditions.
\3\ For ducted units tested without an air filter installed, increase
the applicable tabular value by 0.08 inches of water.


3.1.4.1.2 Cooling Certified Air Volume Rate for Non-ducted Units. For non-ducted units, the Cooling Certified 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 Rate. a. For ducted units that regulate the speed (as opposed to the cfm) of the indoor fan,


where “Cooling Minimum Fan Speed” corresponds to the fan speed used when operating at low compressor capacity (two-capacity system), the fan speed used when operating at the minimum compressor speed (variable-speed system), or the lowest fan speed used when cooling (single-speed compressor and a variable-speed variable-air-volume-rate indoor fan). For such systems, obtain the Cooling Minimum Air Volume Rate regardless of the external static pressure.

b. For ducted units that regulate the air volume rate provided by the indoor fan, the manufacturer must specify the Cooling Minimum Air Volume Rate. For such systems, 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 instability or an automatic shutdown of the indoor blower while being as close to, but not less than,


where ?Pst,A2 is the applicable Table 2 minimum external static pressure that was targeted during the A2 (and B2) Test.

c. For ducted two-capacity units that are tested without an indoor fan installed, the Cooling Minimum Air Volume Rate is the higher of (1) the rate specified by the manufacturer or (2) 75 percent of the Cooling Certified Air Volume Rate. During the laboratory tests on a coil-only (fanless) unit, 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 fan 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 fan, use the lowest fan setting allowed for cooling.

3.1.4.3 Cooling Intermediate Air Volume Rate. a. For ducted units that regulate the speed of the indoor fan,


For such units, obtain the Cooling Intermediate Air Volume Rate regardless of the external static pressure.

b. For ducted units that regulate the air volume rate provided by the indoor fan, the manufacturer must specify the Cooling Intermediate Air Volume Rate. For such systems, conduct the EV Test at an external static pressure that does not cause instability or an automatic shutdown of the indoor blower while being as close to, but not less than,


where ?Pst,A2 is the applicable Table 2 minimum external static pressure that was targeted during the A2 (and B2) Test.

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 Certified Air Volume Rate.

3.1.4.4.1 Ducted heat pumps where the Heating and Cooling Certified Air Volume Rates are the same. a. Use the Cooling Certified Air Volume Rate as the Heating Certified Air Volume Rate for:

1. Ducted heat pumps that operate at the same indoor fan speed during both the A (or A2) and the H1 (or H12) Tests;

2. Ducted heat pumps that regulate fan speed to deliver the same constant air volume rate during both the A (or A2) and the H1 (or H12) Tests; and

3. Ducted heat pumps that are tested without an indoor fan installed (except two-capacity northern heat pumps that are tested only at low capacity cooling—see 3.1.4.4.2).

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. For heat pumps that meet the above criterion “2,” test at an external static pressure that does not cause instability or an automatic shutdown of the indoor blower while being as close to, but not less than, the same Table 2 minimum external static pressure as was specified for the A (or A2) cooling mode test.

3.1.4.4.2 Ducted heat pumps where the Heating and Cooling Certified Air Volume Rates are different due to indoor fan operation. a. For ducted heat pumps that regulate the speed (as opposed to the cfm) of the indoor fan,


For such heat pumps, obtain the Heating Certified Air Volume Rate without regard to the external static pressure.

b. For ducted heat pumps that regulate the air volume rate delivered by the indoor fan, the manufacturer must specify the Heating Certified Air Volume Rate. For such heat pumps, conduct all tests that specify the Heating Certified Air Volume Rate at an external static pressure that does not cause instability or an automatic shutdown of the indoor blower while being as close to, but not less than,


where the Cooling Certified ?Pst is the applicable Table 2 minimum external static pressure that was specified for the A or A2 Test.

c. When testing ducted, two-capacity northern heat pumps (see Definition 1.46), use the appropriate approach of the above two cases for units that are tested with an indoor fan installed. For coil-only (fanless) northern heat pumps, the Heating Certified Air Volume Rate is the lesser of the rate specified by the manufacturer or 133 percent of the Cooling Certified Air Volume Rate. For this latter case, obtain the Heating Certified Air Volume Rate regardless of the pressure drop across the indoor coil assembly.

3.1.4.4.3 Ducted heating-only heat pumps. The manufacturer must specify the Heating Certified Air Volume Rate. Use this value when the following two requirements are satisfied. First, when conducting the H1 or H12 Test (exclusively), the measured air volume rate, when divided by the measured indoor air-side total heating capacity, must not exceed 37.5 cubic feet per minute of standard air (scfm) per 1000 Btu/h. If this ratio is exceeded, reduce the air volume rate until this ratio is equaled. Use this reduced air volume rate for all tests of heating-only heat pumps that call for the Heating Certified Air Volume Rate. The second requirement is as follows:

a. For heating-only heat pumps that are tested with a fixed-speed, multi-speed, or variable-speed variable-air-volume-rate indoor fan installed. For the H1 or H12 Test (exclusively), the measured external static pressure must be equal to or greater than the Table 2 minimum external static pressure that applies given the heating-only heat pump's rated heating capacity. If the Table 2 minimum is not equaled or exceeded, incrementally change the set-up of the indoor fan until the Table 2 requirement is met while maintaining the same air volume rate. If the indoor fan set-up changes cannot provide the necessary external static pressure, then reduce the air volume rate until the correct Table 2 minimum is equaled. For the last scenario, use the reduced air volume rate for all tests that require the Heating Certified Air Volume Rate.

b. For ducted heating-only heat pumps having a constant-air-volume-rate indoor fan. For all tests that specify the Heating Certified Air Volume Rate, obtain an external static pressure that does not cause instability or an automatic shutdown of the indoor blower while being as close to, but not less than, the applicable Table 2 minimum.

c. For ducted heating-only heat pumps that are tested without an indoor fan installed. For 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 Certified Air Volume Rate.

3.1.4.4.4 Non-ducted heat pumps, including non-ducted heating-only heat pumps. For non-ducted heat pumps, the Heating Certified 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. a. For ducted heat pumps that regulate the speed (as opposed to the cfm) of the indoor fan,


where “Heating Minimum Fan Speed” corresponds to the fan speed used when operating at low compressor capacity (two-capacity system), the lowest fan speed used at any time when operating at the minimum compressor speed (variable-speed system), or the lowest fan speed used when heating (single-speed compressor and a variable-speed variable-air-volume-rate indoor fan). For such heat pumps, obtain the Heating Minimum Air Volume Rate without regard to the external static pressure.

b. For ducted heat pumps that regulate the air volume rate delivered by the indoor fan, the manufacturer must specify the Heating Minimum Air Volume Rate. For such heat pumps, 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 instability or an automatic shutdown of the indoor blower while being as close to, but not less than,


is the minimum external static pressure that was targeted during the H12 Test.

c. For ducted two-capacity northern heat pumps that are tested with an indoor fan installed, use the appropriate approach of the above two cases.

d. For ducted two-capacity heat pumps that are tested without an indoor fan installed, use the Cooling Minimum Air Volume Rate as the Heating Minimum Air Volume Rate. For ducted two-capacity northern heat pumps that are tested without an indoor fan installed, use the Cooling Certified Air Volume Rate as the Heating Minimum Air Volume Rate. For ducted two-capacity heating-only heat pumps that are tested without an indoor fan installed, the Heating Minimum Air Volume Rate is the higher of the rate specified by the manufacturer or 75 percent of the Heating Certified Air Volume Rate. During the laboratory tests on a coil-only (fanless) unit, 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 fan 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 fan, use the lowest fan setting allowed for heating.

3.1.4.6 Heating Intermediate Air Volume Rate. a. For ducted heat pumps that regulate the speed of the indoor fan,


For such heat pumps, obtain the Heating Intermediate Air Volume Rate without regard to the external static pressure.

b. For ducted heat pumps that regulate the air volume rate delivered by the indoor fan, the manufacturer must specify the Heating Intermediate Air Volume Rate. For such heat pumps, conduct the H2V Test at an external static pressure that does not cause instability or an automatic shutdown of the indoor blower while being as close to, but not less than,


is the minimum external static pressure that was specified for the H12 Test.

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 Rate. Except for the noted changes, determine the Heating Nominal Air Volume Rate using the approach described in section 3.1.4.6. Required changes include substituting “H1N Test” for H2V Test” within the first section 3.1.4.6 equation, substituting “H1N Test ?Pst” for “H2V Test ?Pst” in the second section 3.1.4.6 equation, substituting “H1N Test” for each “H2V Test”, and substituting “Heating Nominal Air Volume Rate” for each “Heating Intermediate Air Volume Rate.”


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 unit. If 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 ASHRAE Standard 37–88) (incorporated by reference, see §430.22), 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.

3.1.6 Air volume rate calculations. For 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 7.8.3.1 and 7.8.3.2 of ASHRAE Standard 37–88 (incorporated by reference, see §430.22). When using the Outdoor Air Enthalpy Method, follow sections 7.8.3.1 and 7.8.3.2 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.

3.1.7 Test sequence. When testing a ducted unit (except if a heating-only heat pump), conduct the A or A2 Test first to establish the Cooling Certified Air Volume Rate. For ducted heat pumps where the Heating and Cooling Certified Air Volume Rates are different, make the first heating mode test one that requires the Heating Certified Air Volume Rate. For ducted heating-only heat pumps, conduct the H1 or H12 Test first to establish the Heating Certified Air Volume Rate. When conducting an optional 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 if one expects to adjust the indoor fan control options when preparing for the first Minimum Air Volume Rate test. Under the same circumstances, the first test using the Heating Minimum Air Volume Rate should 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 coil. For 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. 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 to minimize the temperature spread.

3.1.9 Control of auxiliary resistive heating elements. Except 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, 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, 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 Certified 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 unit having a single-speed compressor that is tested with a fixed-speed indoor fan installed, with a constant-air-volume-rate indoor fan installed, or with no indoor fan installed. 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, CDc. If the two optional tests are not conducted, assign CDc the default value of 0.25. Table 3 specifies test conditions for these four tests.


Table 3_Cooling Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed-Speed Indoor Fan, a Constant Air Volume Rate Indoor Fan, or
No Indoor Fan
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ( °F) temperature ( °F)
Test description -------------------------------------------------------- Cooling air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
A Test_required (steady, wet coil)............ 80 67 95 \1\ 75 Cooling certified \2\
B Test_required (steady, wet coil)............ 80 67 82 \1\ 65 Cooling certified \2\
C Test_optional (steady, dry coil)............ 80 (\3\) 82 ............ Cooling certified \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.
\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.


3.2.2 Tests for a unit having a single-speed compressor and a variable-speed variable-air-volume-rate indoor fan installed.

3.2.2.1 Indoor fan capacity modulation that correlates with the outdoor dry bulb temperature. 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, CDc. If the two optional tests are not conducted, assign CDc the default value of 0.25. Table 4 specifies test conditions for these six tests.

3.2.2.2 Indoor fan capacity modulation based on adjusting the sensible to total (S/T) cooling capacity ratio. The testing requirements are the same as specified in section 3.2.1 and Table 3. Use a Cooling Certified Air Volume Rate that represents a normal residential 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 4_Cooling Mode Test Conditions for Units Having a Single-Speed Compressor and a Variable Air Volume Rate Indoor Fan That correlates With the
Outdoor Dry Bulb Temperature (Sec. 3.2.2.1)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ( °F) temperature ( °F)
Test description -------------------------------------------------------- Cooling air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
A2 Test_required (steady, wet coil)........... 80 67 95 \1\ 75 Cooling certified \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 certified \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.
\3\ Defined in section 3.1.4.2.
\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.


3.2.3 Tests for a unit having a two-capacity compressor. (See Definition 1.45.) a. 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, CDc. If the two optional tests are not conducted, assign CDc the default value of 0.25. Table 5 specifies test conditions for these six tests.

b. For units having a variable speed indoor fan that is modulated to adjust the sensible to total (S/T) cooling capacity ratio, use Cooling Certified and Cooling Minimum Air Volume Rates that represent a normal residential installation. Additionally, if conducting the optional 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 Definition 1.46) in the same way as a single speed heat pump with the unit operating exclusively at low compressor capacity (see section 3.2.1 and Table 3).

d. If a two-capacity air conditioner or heat pump locks out low capacity operation at outdoor temperatures that are less than 95 °F, conduct the A1 Test using the outdoor temperature conditions listed for the F1 Test in Table 6 rather than using the outdoor temperature conditions listed in Table 5 for the A1 Test.


Table 5_Cooling Mode Test Conditions for Units Having a Two-Capacity Compressor
----------------------------------------------------------------------------------------------------------------
Air entering Air entering
indoor unit outdoor unit
temperature ( temperature ( Compressor
Test description °F) °F) capacity Cooling air volume rate
----------------------------------------
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
A2 Test_required (steady, 80 67 95 \1\ 75 High Cooling Certified \2\
wet coil).
A1 Test_required (steady, 80 67 95 \1\ 75 Low Cooling Minimum \3\
wet coil).
B2 Test_required (steady, 80 67 82 \1\ 65 High Cooling Certified \2\
wet coil).
B1 Test_required (steady, 80 67 82 \1\ 65 Low Cooling Minimum \3\
wet coil).
C1 Test \4\_optional 80 (\4\) 82 ........ Low Cooling Minimum \3\
(steady, dry coil).
D1 Test \4\_optional 80 (\4\) 82 ........ Low (\5\)
(cyclic, dry coil).
----------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in section 3.1.4.1.
\3\ Defined in section 3.1.4.2.
\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.


3.2.4 Tests for a unit having a variable-speed compressor. 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,CDc. If the two optional tests are not conducted, assign CDc the default value of 0.25. Table 6 specifies test conditions for these seven tests. Determine the intermediate compressor speed cited in Table 6 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 fan speed to adjust the sensible to total (S/T) cooling capacity ratio, use Cooling Certified, Cooling Intermediate, and Cooling Minimum Air Volume Rates that represent a normal residential installation. Additionally, if conducting the optional dry-coil tests, operate the unit in the same S/T capacity control mode as used for the F1 Test.


Table 6_Cooling Mode Test Conditions for Units Having a Variable-Speed Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering Air entering
indoor unit outdoor unit
Temperature ( Temperature (
Test description °F) °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 Maximum Cooling Certified \2\
B2 Test_required (steady, wet coil).......... 80 67 82 \1\ 65 Maximum Cooling Certified \2\
EV Test_required (steady, wet coil).......... 80 67 87 \1\ 69 Intermediate Cooling Intermediate \3\
B1 Test_required (steady, wet coil).......... 80 67 82 \1\ 65 Minimum Cooling Minimum \4\
F1 Test_required (steady, wet coil).......... 80 67 67 \1\ 53.5 Minimum Cooling Minimum \4\
G1 Test \5\_optional (steady, dry coil)...... 80 (\5\) 67 ........ Minimum Cooling Minimum \4\
I1 Test \5\_optional (cyclic, dry coil)...... 80 (\5\) 67 ........ 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.
\3\ Defined in section 3.1.4.3.
\4\ Defined in section 3.1.4.2.
\5\ 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.)
\6\ 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 G1 Test.


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 fan 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 Definition 1.15):

(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 cases where its control is required, the water vapor content of the air entering the outdoor coil.

Refer to section 3.11 for additional requirements that depend on the selected secondary test method.

b. After satisfying the pretest equilibrium requirements, make the measurements specified in Table 5 of ASHRAE Standard 37–88 (incorporated by reference, see §430.22) for the Indoor Air Enthalpy method and the user-selected secondary method. Except for external static pressure, make the Table 5 measurements at equal intervals that span 10 minutes or less. Measure external static pressure every 5 minutes or less. Continue data sampling until reaching a 30-minute period (e.g., four consecutive 10-minute samples) where the test tolerances specified in Table 7 are satisfied. For those continuously recorded parameters, use the entire data set from the 30-minute interval to evaluate Table 7 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 as specified in section 7.3.3.1 of ASHRAE Standard 37–88 (incorporated by reference, see §430.22). 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. Assign the average total space cooling capacity and electrical power consumption over the 30-minute data collection interval to the variables Q ck(T) and E ck(T), respectively. For these two 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 maximum speed, k=1 to denote low capacity or minimum speed, and k=v to denote the intermediate speed.

d. For units tested without an indoor fan installed, decrease Q ck(T) by


and increase E ck(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 7_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 Test condition tolerance
\1\ \2\
----------------------------------------------------------------------------------------------------------------
Indoor dry-bulb, °F
Entering temperature.................................. 2.0 0.5
Leaving temperature................................... 2.0
Indoor wet-bulb, °F
Entering temperature.................................. 1.0 \3\ 0.3
Leaving temperature................................... \3\ 1.0
Outdoor dry-bulb, °F
Entering temperature.................................. 2.0 0.5
Leaving temperature................................... \4\ 2.0
Outdoor wet-bulb, °F
Entering temperature.................................. 1.0 \5\ 0.3
Leaving temperature................................... \4\ 1.0
External resistance to airflow, inches of water........... 0.05 \6\ 0.02
Electrical voltage, % of rdg.............................. 2.0 1.5
Nozzle pressure drop, % of rdg............................ 2.0
----------------------------------------------------------------------------------------------------------------
\1\ See Definition 1.41.
\2\ See Definition 1.40.
\3\ Only applies during wet coil tests; does not apply during steady-state, dry coil cooling mode tests.
\4\ Only applies when using the Outdoor Air Enthalpy Method.
\5\ Only applies during wet coil cooling mode tests where the unit rejects condensate to the outdoor coil.
\6\ Only applies when testing non-ducted units.


d. For air conditioners and heat pumps having a constant-air-volume-rate indoor fan, 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 (?Pmin) by 0.03 inches of water or more.

1. Measure the average power consumption of the indoor fan motor (E fan,1) and record the corresponding external static pressure (?P1) 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 ?P1 + (?P1 - ?Pmin).

3. After re-establishing steady readings of the fan motor power and external static pressure, determine average values for the indoor fan power (E fan,2) and the external static pressure (?P2) by making measurements over a 5-minute interval.

4. Approximate the average power consumption of the indoor fan motor at ?Pmin using linear extrapolation:


5. Increase the total space cooling capacity, Q ck(T), by the quantity (E fan,1 - E fan,min), when expressed on a Btu/h basis. Decrease the total electrical power, E ck(T), by the same fan power difference, now expressed in watts.

3.4 Test procedures for the optional steady-state dry coil cooling mode tests (the C, C1, 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 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(T). In preparing for the section 3.5 cyclic test, 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 fan (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 fan turned off (see section 3.5), include the electrical power used by the indoor fan motor among the recorded parameters from the 30-minute test.

3.5 Test procedures for the optional cyclic dry coil cooling mode tests (the D, D1, and I1 Tests). a. 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 fan, the manufacturer has the option of electing at the outset whether to conduct the cyclic test with the indoor fan enabled or disabled. Always revert to testing with the indoor fan disabled if cyclic testing with the fan enabled is unsuccessful. (continued)