USE OM - JANUARY 2017
73
Heating mode high stage
Heating mode low stage
7.6.1.3
For variable speed product, each individual stage shall be considered an operational
mode.
7.6.1.4
The independent third party lab shall work with the Participant to identify any other test
where free air may be required
7.6.2
For each operational mode identified in Section 7.6.1, there shall be one (1) free air (FA) test performed
with no ductwork or attachments added to the Unit Under Test (UUT). This FA test may be conducted on any test
in a given operational mode. All steady state requirements per AHRI Standard 210/240, ASHRAE Standard 37
and 10 CFR 430 Appendix M to Subpart B shall be met. During this FA test, the following items shall be recorded
along with all other data requirements:
7.6.2.1
Either Fan motor current, Fan motor speed or fan motor watts.
7.6.2.2
When applicable refrigerant pressures at the high side and low side unit service
connections closest to compressor.
7.6.2.3
When pressures cannot be measured on round tube plate fin coils, the midpoint of the
uppermost refrigerant circuit, and the midpoint of the lowermost refrigerant circuit of the outdoor coil.
7.6.3
Outdoor duct losses shall be calculated for all closed duct tests per ASHRAE Standard 37 Section
7.3.3.3 for cooling mode and ASHRAE Standard 37 Section 7.3.4.3 for heating mode. Net capacities shall be
adjusted accordingly.
7.6.4
Immediately following the FA test conducted per Section 7.6.2 of this appendix, the ductwork meeting
requirements of Section 7.5 shall be added to the Outdoor Unit, and a Closed Duct test shall be conducted. All
steady state requirements per AHRI Standard 210/240, ASHRAE Standard 37 and 10 CFR 430 Appendix M to
Subpart B shall be met. During this CD test the following parameters shall be met:
7.6.4.1
The average inlet indoor DB temperature must be within 0.25°F of the FA test.
7.6.4.2
The average inlet indoor WB temperature must be within 0.15°F of the FA test.
7.6.4.3
The average inlet outdoor DB temperature must be within 0.25°F of the FA test.
7.6.4.4
The average inlet outdoor WB temperature must be within 0.25°F of the FA test.
7.6.4.5
Fan motor current, if measured shall be within 3.0% of the value measured in Section
7.6.1.1.
7.6.4.6
Fan speed, if measured for Section 7.6.1.2, shall be within 5 rpm of the FA test.
7.6.4.7
Fan watts, if measured for Section 7.6.1.2, shall be within 3.0% of the FA test.
7.6.4.8
Refrigerant high side pressures of the closed duct test measured per Section 7.6.1.3
shall be within 2 psig of the FA test for systems using refrigerants R-410A or R-22.
7.6.4.8.1
For other refrigerants, the pressure of the closed duct test shall be within
0.5°F saturation temperature of the FA test.
7.6.4.9
Refrigerant low side pressures of the closed duct test measured per Section 7.6.1.3
shall be within 0.5 psig of the FA test for systems using refrigerants R-410A or R-22.
