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7. Check that the compressor is operating correctly.
The scroll compressors in these units MUST operate
in the proper rotation. To ensure the compressors
are operating in the correct direction, check the
compressor discharge line pressure or temperature
after the compressor is started. The discharge
pressure and discharge line temperature should
increase. If this does not occur and the compressor
is producing an exceptional amount of noise,this
indicates that there is a phasing issue. Perform the
following to correct:
7.1 Turn power to the unit OFF.
7.2 Switch any two leads of power supply at unit
Single Point Power Block.
7.3 Turn power to the unit ON.
7.4 Perform step 7 again.
8. Turn the temperature setting to the highest position,
stopping the unit. The indoor blower will continue to
run for 60 seconds.
9. Turn the thermostat system switch to "OFF" and
disconnect all power when servicing the unit.
NOTE: The compressor has 180 second re-start
delay on timer to avoid short cycling.
HIGH VOLTAGE!
Disconnect all power before
servicing or installing this unit.
Multiple power sources may be
present. Failure to do so may cause
property damage, personal injury or
death.
Heat Pump Start-Up Procedure
10. Check the cooling mode for the heat pump in
the same manner as above. The reversing valve
is energized when the thermostat is placed in
the cooling position. A clicking sound should be
noticeable from the reversing valve. By lowering the
temperature setting to call for cooling, the solenoid
valve is energized. The compressor, blower and fan
should then be running. After the cooling mode is
checked out, turn the thermostat system switch to
"OFF".
11. Turn the thermostat system switch to "HEAT" and fan
switch to "AUTO".
12. Slowly raise the heating temperature setting. When
the heating first stage makes contact, stop raising
the temperature setting.. The compressor, blower
and fan should now be running with the reversing
valve in the deenergized (heating) position. After
giving the unit time to settle out, make sure the unit
is supplying heated air.
WARNING
Note: If the outdoor ambient is above 80°F, the
unit may trip on its high pressure cut out when on
heating. The compressor should stop. The heating
cycle must be thoroughly checked, so postpone
the test to another day when conditions are more
suitable but-DO NOT FAIL TO TEST. If the outdoor
ambient is low and the unit operates properly on the
heating cycle, you may check the pressure cutout
operation by blocking off the indoor return air until
the unit trips.
13. Once the heating has been confirmed, raise the
temperature setting until the second stage heating
makes contact. Supplemental resistance heat, if
installed should now come on. Make sure it operates
properly.
14. For thermostats with emergency heat switch, set
thermostat to Emergency Heat mode. The heat
pump will stop, the blower will continue to run, all
heaters will come on and the thermostat emergency
heat light will come on. Confirm heaters operate
normally.
Final System Checks
15. Check to see if all supply and return air grilles are
adjusted and the air distribution system is balanced
for the best compromise between heating and
cooling.
16. Check for air leaks in the ductwork. See Sections
on Air Flow Adjustments.
17. Make sure the unit is free of "rattles", and the tubing
in the unit is free from excessive vibration. Also
make sure tubes or lines are not rubbing against
each other or sheet metal surfaces or edges. If so,
correct the trouble.
18. Set the thermostat at the appropriate setting for
cooling and heating or automatic changeover for
normal use.
19. Be sure the Owner is instructed on the unit
operation, filter, servicing, correct thermostat
operation, etc.
Refrigeration Performance Check
Check that compressor RLA corresponds to values shown
in Appendix B. RLA draw can be much lower than values
listed at low load conditions and low ambient condensing
temperatures. Values in Appendix B can slightly exceed
at high load conditions and high ambient condensing
temperatures.
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