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(continued)

b. For units having a single-speed or two-capacity compressor, cycle the compressor OFF for 24 minutes and then ON for 6 minutes (?tcyc,dry = 0.5 hours). For units having a variable-speed compressor, cycle the compressor OFF for 48 minutes and then ON for 12 minutes (?tcyc,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.

c. Sections 3.5.1 and 3.5.2 specify airflow requirements through the indoor coil of ducted and non-ducted systems, respectively. In all cases, use the exhaust fan of the airflow measuring apparatus (covered under section 2.6) along with the indoor fan 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 fan 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 fan, 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 fan 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 blower, temporarily remove the blower.

e. After completing a minimum of two complete compressor OFF/ON cycles, determine the overall cooling delivered and total electrical energy consumption during any subsequent data collection interval where the test tolerances given in Table 8 are satisfied. If available, use electric resistance heaters (see section 2.1) to minimize the variation in the inlet air temperature.

f. With regard to the Table 8 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 fan (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 ?tcyc,dry. For ducted units tested with an indoor fan installed and operating, integrate electrical power from indoor fan OFF to indoor fan 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 8_Test Operating and Test Condition Tolerances for Cyclic Dry Coil
Cooling Mode Tests
------------------------------------------------------------------------
Test Test
Operating Condition
Tolerance Tolerance
\1\ \2\
------------------------------------------------------------------------
Indoor entering dry-bulb temperature \3\, 2.0 0.5
°F.....................................
Indoor entering wet-bulb temperature, °F ............ (\4\)
Outdoor entering dry-bulb temperature \3\, 2.0 0.5
°F.....................................
External resistance to airflow \3\, inches 0.05
of water...................................
Airflow nozzle pressure difference or 2.0 \5\ 2.0
velocity pressure \3\, % of reading........
Electrical voltage \6\, % of rdg............ 2.0 1.5
------------------------------------------------------------------------
\1\ See Definition 1.41.
\2\ See Definition 1.40.
\3\ 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 fan that ramps, the
tolerances listed for the external resistance to airflow apply from 30
seconds after achieving full speed until ramp down begins.
\4\ Shall at no time exceed a wet-bulb temperature that results in
condensate forming on the indoor coil.
\5\ The test condition shall be the average nozzle pressure difference
or velocity pressure measured during the steady-state dry coil test.
\6\ Applies during the interval when at least one of the following_the
compressor, the outdoor fan, or, if applicable, the indoor fan_are
operating except for the first 30 seconds after compressor start-up.


i. If the Table 8 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), and Wn are the values recorded during the section 3.4 dry coil steady-state test and,


Tal(t) = dry bulb temperature of the air entering the indoor coil at time t, °F.

Ta2(t) = dry bulb temperature of the air leaving the indoor coil at time t, °F.

t1 = 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.

t2 = the elapsed time when indoor coil airflow ceases, hr.

3.5.1 Procedures when testing ducted systems. The automatic controls that are normally installed with 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, if installed, the indoor fan of the test unit). For example, for ducted units tested without an indoor fan installed but rated based on using a fan time delay relay, control the indoor coil airflow according to the rated ON and/or OFF delays provided by the relay. For ducted units having a variable-speed indoor fan 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 units tested without an indoor fan installed, cycle the indoor coil airflow in unison with the cycling of the compressor. Close air dampers on the inlet (section 2.5.1) and outlet side (sections 2.5 and 2.5.4) 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 fan. For ducted units tested without an indoor fan installed (excluding the special case where a variable-speed fan is temporarily removed), increase ecyc,dry by the quantity,


and decrease qcyc,dry by,


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 fan that is disabled during the cyclic test, increase ecyc,dry and decrease qcyc,dry based on:

a. The product of [t2 - t1] and the indoor fan power measured during or following the dry coil steady-state test; or,

b. The following algorithm if the indoor fan ramps its speed when cycling.

1. Measure the electrical power consumed by the variable-speed indoor fan 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 fan 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 a manufacturer-supplied ramp interval exceeds 45 seconds, use a 45-second ramp interval nonetheless when estimating the fan energy.

The manufacturer is allowed to choose option a, and forego the extra testing burden of option b, even if the unit ramps indoor fan speed when cycling.

3.5.2 Procedures when testing non-ducted systems. Do not use air dampers when conducting cyclic tests on non-ducted 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 fan 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 fan during the 3 minutes prior to compressor cut-on from the integrated electrical energy, ecyc,dry. Add the electrical energy used by the indoor fan during the 3 minutes after compressor cutoff to the integrated cooling capacity, qcyc,dry. For the case where the non-ducted unit uses a variable-speed indoor fan which is disabled during the cyclic test, correct ecyc,dry and qcyc,dry using the same approach as prescribed in section 3.5.1 for ducted units having a disabled variable-speed indoor fan.

3.5.3 Cooling mode cyclic degradation coefficient calculation. Use two optional dry-coil tests 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. Evaluate CDc 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 CDc to the nearest 0.01. If CDc 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 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 three tests: The High Temperature (H1) Test, the Frost Accumulation (H2) Test, and the Low Temperature (H3) Test. Conduct the optional High Temperature Cyclic (H1C) Test to determine the heating mode cyclic degradation coefficient, CDh. If this optional test is not conducted, assign CDh the default value of 0.25. Test conditions for these four tests are specified in Table 9.


Table 9_Heating 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
Temperature ( °F) unit Temperature (
Test description -------------------------- °F) Heating air volume rate
--------------------------
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H1 Test (required, steady)...................... 70 60(max) 47 43 Heating Certified \1\
H1C Test (optional, cyclic)..................... 70 60(max) 47 43 (\2\)
H2 Test (required).............................. 70 60(max) 35 33 Heating Certified \1\
H3 Test (required, steady)...................... 70 60(max) 17 15 Heating Certified \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.4.
\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.


3.6.2 Tests for a heat pump having a single-speed compressor and a variable-speed, variable-air-volume-rate indoor fan: capacity modulation correlates with outdoor dry bulb temperature. 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) is optional. Conduct the optional High Temperature Cyclic (H1C1) Test to determine the heating mode cyclic degradation coefficient, CDh. If this optional test is not conducted, assign CDh the default value of 0.25. Table 10 specifies test conditions for these seven tests. If the optional H21 Test is not done, 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; 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; 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.


Table 10_Heating Mode Test Conditions for Units Having a Single-Speed Compressor and a Variable Air Volume Rate Indoor Fan
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit temperature Air entering outdoor
( °F) unit temperature (
Test description ---------------------------------------- °F) Heating air volume rate
--------------------------
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H12 Test (required, steady).............. 70 60(max).................. 47 43 Heating Certified.\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 Certified.\1\
H21 Test (optional)...................... 70 60(max).................. 35 33 Heating Minimum.\2\
H32 Test (required, steady).............. 70 60(max).................. 17 15 Heating Certified.\1\
H31 Test (required, steady).............. 70 60(max).................. 17 15 Heating Minimum.\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.4.
\2\ Defined in section 3.1.4.5.
\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.


3.6.3 Tests for a heat pump having a two-capacity compressor (see Definition 1.45), including two-capacity, northern heat pumps (see Definition 1.46). 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). 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 seasonal performance calculations, and

2. The heat pump's controls allow low capacity operation at outdoor temperatures of 37 °F and less.

b. Conduct the optional Maximum Temperature Cyclic Test (H0C1) to determine the heating mode cyclic degradation coefficient, CDh. If this optional test is not conducted, assign CDh the default value of 0.25. Table 11 specifies test conditions for these eight tests.


Table 11_Heating Mode Test Conditions for Units Having a Two-Capacity Compressor
----------------------------------------------------------------------------------------------------------------
Air entering indoor Air entering outdoor
unit Temperature ( unit Temperature (
Test description °F) °F) Compressor Heating air volume rate
-------------------------------------------- capacity
Dry Bulb Wet Bulb Dry Bulb Wet Bulb
----------------------------------------------------------------------------------------------------------------
H01 Test (required, steady). 70 60(max) 62 56.5 Low........ Heating Minimum \1\
H0C1 Test (optional, cyclic) 70 60(max) 62 56.5 Low........ (\2\)
H12 Test (required, steady). 70 60(max) 47 43 High....... Heating Certified \3\
H11 Test (required, steady). 70 60(max) 47 43 Low........ Heating Minimum \1\
H22 Test (required)......... 70 60(max) 35 33 High....... Heating Certified \3\
H21 Test \4\ (required)..... 70 60(max) 35 33 Low........ Heating Minimum \1\
H32 Test (required, steady). 70 60(max) 17 15 High....... Heating Certified \3\
H31 Test \4\ (required, 70 60(max) 17 15 Low........ Heating Minimum \1\
steady).
----------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5.
\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 H01 Test.
\3\ Defined in section 3.1.4.4.
\4\ 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 HSPF calculations.


3.6.4 Tests for a heat pump having a variable-speed compressor. a. Conduct one Maximum Temperature Test (H01), two High Temperature Tests (H12 and H11), one Frost Accumulation Test (H2V), and one Low Temperature Test (H32). Conducting one or both of the following tests is optional: An additional High Temperature Test (H1N ) and an additional Frost Accumulation Test (H22). Conduct the optional Maximum Temperature Cyclic (H0C1) Test to determine the heating mode cyclic degradation coefficient, CDh. If this optional test is not conducted, assign CDh the default value of 0.25. Table 12 specifies test conditions for these eight tests. Determine the intermediate compressor speed cited in Table 12 using the heating mode maximum and minimum compressors speeds and:


where a tolerance of plus 5 percent or the next higher inverter frequency step from that calculated is allowed. If the H22 Test is not done, use the following equations to approximate the capacity and electrical power at the H22 test conditions:


b. Determine the quantities Q hk=2(47) and from E hk=2(47) from the H12 Test and evaluate them according to section 3.7. Determine the quantities Q hk=2(17) and E hk=2(17) from the H32 Test and evaluate them according to section 3.10. For heat pumps where the heating mode maximum compressor speed exceeds its cooling mode maximum compressor speed, conduct the H1N Test if the manufacturer requests it. If the H1N Test is done, operate the heat pump's compressor at the same speed as the speed used for the cooling mode A2 Test. Refer to the last sentence of section 4.2 to see how the results of the H1N Test may be used in calculating the heating seasonal performance factor.


Table 12_Heating Mode Test Conditions for Units Having a Variable-Speed Compressor
----------------------------------------------------------------------------------------------------------------
Air entering indoor Air entering outdoor
unit temperature ( unit temperature (
Test description °F) °F) Compressor Heating air volume rate
-------------------------------------------- speed
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
H01 Test (required, steady). 70 60\(max)\ 62 56.5 Minimum.... Heating Minimum.\1\
H0C1 Test (optional, cyclic) 70 60\(max)\ 62 56.5 Minimum.... (\2\)
H12 Test (required, steady). 70 60\(max)\ 47 43 Maximum.... Heating Certified.\3\
H11 Test (required, steady). 70 60\(max)\ 47 43 Minimum.... Heating Minimum.\1\
H1N Test (optional, steady). 70 60\(max)\ 47 43 Cooling Heating Nominal.\4\
Mode
Maximum.
H22 Test (optional)......... 70 60\(max)\ 35 33 Maximum.... Heating Certified.\3\
H2V Test (required)......... 70 60\(max)\ 35 33 Intermediat Heating Intermediate.\5\
e.
H32 Test (required, steady). 70 60\(max)\ 17 15 Maximum.... Heating Certified.\3\
----------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5.
\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 H01 Test.
\3\ Defined in section 3.1.4.4.
\4\ Defined in section 3.1.4.7.
\5\ Defined in section 3.1.4.6.


3.6.5 Additional test for a heat pump having a heat comfort controller. Test any heat pump that has a heat comfort controller (see Definition 1.28) 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 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.)

3.7 Test procedures for steady-state Maximum Temperature and High Temperature heating mode tests (the H01, H1, H12, H11, and H1N Tests). 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 fan 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 for additional requirements that depend on the selected secondary test method. 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 a 30-minute period (e.g., four consecutive 10-minute samples) is reached where the test tolerances specified in Table 13 are satisfied. For those continuously recorded parameters, use the entire data set for the 30-minute interval when evaluating Table 13 compliance. Determine the average electrical power consumption of the heat pump over the same 30-minute interval.


Table 13_Test Operating and Test Condition Tolerances for Section 3.7
and Section 3.10 Steady-State Heating Mode Tests
------------------------------------------------------------------------
Test Test
operating condition
tolerance 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 .........
Leaving temperature........................... 1.0 .........
Outdoor dry-bulb, °F:
Entering temperature.......................... 2.0 0.5
Leaving temperature........................... \2\ 2.0 .........
Outdoor wet-bulb, °F:
Entering temperature.......................... 1.0 0.3
Leaving temperature........................... \3\ 1.0 .........
External resistance to airflow, inches of water... 0.05 \4\ 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 when the Outdoor Air Enthalpy Method is used.
\4\ Only applies when testing non-ducted units.


b. Calculate indoor-side total heating capacity as specified in section 7.3.4.1 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. Assign the average space heating capacity and electrical power over the 30-minute data collection interval to the variables Q hk and E hk(T) respectively. The “T” and superscripted “k” are the same as described in section 3.3. Additionally, for the heating mode, use the superscript to denote results from the optional H1N Test, if conducted.

c. For heat pumps tested without an indoor fan installed, increase Q hk(T) by


and increase E hk(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 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 13 test tolerances are satisfied. In this case, use only the results from the second 30-minute data collection interval to evaluate Q hk(47) and E hk(47).

d. If conducting the optional cyclic heating mode test, which is described in section 3.8, 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 fan motor (E fan,1):

1. The section 3.8 cyclic test will be conducted and the heat pump has a variable-speed indoor fan that is expected to be disabled during the cyclic test; or

2. The heat pump has a (variable-speed) constant-air volume-rate indoor fan and during the steady-state test the average external static pressure (?P1) exceeds the applicable section 3.1.4.4 minimum (or targeted) external static pressure (?Pmin) 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 ?P1):

i. 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).

ii. After re-establishing steady readings for 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.

iii. Approximate the average power consumption of the indoor fan motor if the 30-minute test had been conducted at ?Pmin using linear extrapolation:


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

3.8 Test procedures for the optional cyclic heating mode tests (the H0C1, H1C, and H1C1 Tests). a. Except as noted below, conduct the cyclic heating mode test as specified in section 3.5. 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 14 rather than Table 8. Record the outdoor coil entering wet-bulb temperature according to the requirements given in section 3.5 for the outdoor coil entering dry-bulb temperature. Drop the subscript “dry” used in variables cited in section 3.5 when referring to quantities from the cyclic heating mode test. Determine the total space heating delivered during the cyclic heating test, qcyc, as specified in section 3.5 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 G using,


b. For ducted heat pumps tested without an indoor fan installed (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 fan 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 fan 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 calculation. Use the results from the optional 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. If the optional test is not conducted, assign CDh the default value of 0.25.


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.

?tcyc = 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 14_Test operating and test condition tolerances for cyclic heating
mode tests.
------------------------------------------------------------------------
Test Test
operating condition
tolerance tolerance
\1\ \2\
------------------------------------------------------------------------
Indoor entering dry-bulb temperature,\3\ °F... 2.0 0.5
Indoor entering wet-bulb temperature,\3\ °F... 1.0
Outdoor entering dry-bulb temperature,\3\ °F.. 2.0 0.5
Outdoor entering wet-bulb temperature,\3\ °F.. 2.0 1.0
External resistance to air-flow,\3\ inches of 0.05
water............................................
Airflow nozzle pressure difference or velocity 2.0 \4\ 2.0
pressure,\3\ % of reading........................
Electrical voltage,\5\ % of rdg................... 2.0 1.5
------------------------------------------------------------------------
\1\ See Definition 1.41.
\2\ See Definition 1.40.
\3\ 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 fan that ramps, the
tolerances listed for the external resistance to airflow shall apply
from 30 seconds after achieving full speed until ramp down begins.
\4\ The test condition shall be the average nozzle pressure difference
or velocity pressure measured during the steady-state test conducted
at the same test conditions.
\5\ Applies during the interval that at least one of the following_the
compressor, the outdoor fan, or, if applicable, the indoor fan_are
operating, except for the first 30 seconds after compressor start-up.


3.9 Test procedures for Frost Accumulation heating mode tests (the H2, H22, H2V, and H21 Tests). a. Confirm that the defrost controls of the heat pump are set as specified in section 2.2.1. 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 Definition 1.42), 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 12 hours, immediately conclude the test and use the results from the full 12-hour period to calculate the average space heating capacity and average electrical power consumption. For heat pumps that turn the indoor fan 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 fan. If it is installed, use the outlet damper box described in section 2.5.4.1 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 15 during both the preliminary and official test periods. As noted in Table 15, 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 15) and (2) when defrosting, plus these same first 10 minutes after defrost termination (Sub-interval D, as described in Table 15). Evaluate compliance with Table 15 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 15 at equal intervals that span 10 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 fan 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 heat pumps tested without an indoor fan installed, determine the corresponding cumulative time (in hours) of indoor coil airflow, ?ta. Sample measurements used in calculating the air volume rate (refer to sections 7.8.3.1 and 7.8.3.2 of ASHRAE Standard 37–88 (incorporated by reference, see §430.22)) at equal intervals that span 10 minutes or less. Record the electrical energy consumed, expressed in watt-hours, from defrost termination to defrost termination, eDEFk(35), as well as the corresponding elapsed time in hours, ?tFR.


Table 15_Test Operating and Test Condition Tolerances for Frost
Accumulation Heating Mode Tests.
------------------------------------------------------------------------
Test operating tolerance Test
\1\ condition
-------------------------- tolerance
Sub- Sub- \2\ Sub-
interval H interval D interval H
\3\ \4\ \3\
------------------------------------------------------------------------
Indoor entering dry-bulb 2.0 \5\ 4.0 0.5
temperature, °F.............
Indoor entering wet-bulb 1.0 ...........
temperature, °F.............
Outdoor entering dry-bulb 2.0 10.0 1.0
temperature, °F.............
Outdoor entering wet-bulb 1.5 ........... 0.5
temperature, °F.............
External resistance to airflow, 0.05 ........... 0.02 \6\
inches of water.................
Electrical voltage, % of rdg..... 2.0 ........... 1.5
------------------------------------------------------------------------
\1\ See Definition 1.41.
\2\ See Definition 1.40.
\3\ Applies when the heat pump is in the heating mode, except for the
first 10 minutes after termination of a defrost cycle.
\4\ 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.
\5\ For heat pumps that turn off the indoor fan during the defrost
cycle, the noted tolerance only applies during the 10 minute interval
that follows defrost termination.
\6\ Only applies when testing non-ducted heat pumps.


3.9.1 Average space heating capacity and electrical power calculations. a. Evaluate average space heating capacity, Q hk(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.

?tFR = t2 - t1, the elapsed time from defrost termination to defrost termination, hr.


Tal(t) = dry bulb temperature of the air entering the indoor coil at elapsed time t, °F; only recorded when indoor coil airflow occurs; assigned the value of zero during periods (if any) where the indoor fan cycles off.

Ta2(t) = dry bulb temperature of the air leaving the indoor coil at elapsed time t, °F; only recorded when indoor coil airflow occurs; assigned the value of zero during periods (if any) where the indoor fan cycles off.

t1 = the elapsed time when the defrost termination occurs that begins the official test period, hr.

t2 = 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.

b. Evaluate average electrical power, E hk(35), when expressed in units of watts, using:


For heat pumps tested without an indoor fan installed, increase Q hk(35) by,


and increase E hk(35) by,


where V s is the average indoor air volume rate measured during the Frost Accumulation heating mode test and is expressed in units of cubic feet per minute of standard air (scfm).

c. For heat pumps having a constant-air-volume-rate indoor fan, 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 (?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 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 ?P1 + (?P1 - ?Pmin).

3. After re-establishing steady readings for 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 had the Frost Accumulation heating mode test been conducted at ?Pmin using linear extrapolation:


5. Decrease the total heating capacity, Q hk(35), by the quantity [(E fan,1 - E fan,min)· (?t a/?t FR], when expressed on a Btu/h basis. Decrease the total electrical power, Ehk(35), by the same quantity, now expressed in watts.

3.9.2 Demand defrost credit. a. Assign the demand defrost credit, Fdef, that is used in section 4.2 to the value of 1 in all cases except for heat pumps having a demand-defrost control system(Definition 1.21). For such qualifying heat pumps, evaluate Fdef using, (continued)