Daikin DRG0361DL00001S Service Instructions Manual page 42

SYSTEM OPERATION
5. Compressor contactor closes its contacts to provide
power to the compressor motor. In addition, the
condenser fan motor is energized through the
compressor contactor.
BURN HAZARD!
Do not touch! Discharge line may be hot!
6. Check that the compressor is operating correctly.
The scroll compressors in these units MUST operate
in the proper rotation. To ensure the compressor
is 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, perform the
following checks.
• If the compressor is operating backward, disconnect
the unit power supply and lock it in the "OFF" position.
Switch two leads of the power supply at the unit Single
Point Power Block. Reconnect power and check for
compressor and condenser fan motor operation.
7. With all safety devices closed, the system will
continue cooling operation until the room
temperature is satisfied.
8. Increasing the room cooling setpoint to a value above
the current room temperature will simulate a satisfied
thermostat. The compressor and the supply fan will
cycle off.
9. After a time delay of approximately 3 minutes, the
compressor control circuits will be ready to respond
to a subsequent call for cooling.
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.
42
WARNING
Final System Checks
1. 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.
2. Check for air leaks in the ductwork. See Sections on
Air Flow Adjustments.
3. 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.
4. Set the thermostat at the appropriate setting for
cooling and heating or automatic changeover for
normal use.
5. Be sure the Owner is instructed on the unit operation,
filter, servicing, correct thermostat operation, etc.