Cu-4E24Rbu - Panasonic CU-4E24RBU Service Manual

14.2 CU-4E24RBU

14.2.1 Pump down operation (SW1)

Operate the pump down process according to the following procedure.
Confirm the valve on the liquid side and gas side are open.
o
Press PUMP DOWN button (SW1) on the Display PCB inside the outdoor unit for more than 5 seconds.
o
Pump down (cooling) operation is performed for 15 minutes.
Set the liquid side 3 way valve to close position and wait until the pressure gauge indicates 0.01MPa
o
(1.45 PSI).
Immediate set the gas side valve to close position and then press the PUMP DOWN button (SW1) to stop the
o
pump down operation.
NOTE: Pump down operation will stop automatically after 15 minutes if PUMP DOWN switch (SW1) is not pressed
again. Pump down operation is not started within 3 minutes after compressor is stopped.
LED 2 3 4
O O O O
O O O
O O
O
: Flashing
O
14.2.2 Test Run Operation

Test operation can be carried out using OPERATION TEST button (SW2) on the Display PCB inside the outdoor
unit.

For Cooling test, press the OPERATION TEST button (SW2) for 5 seconds or more but less than 10 seconds,
LED1 and LED 2 will illuminate when shift into cooling test operation.

For Heating test, press the OPERATION TEST button (SW2) for more than 10 seconds, LED 1 and LED 3 will
illuminate when shift into heating test operation.

Press the OPERATION TEST button (SW2) again to cancel test operation.
Fig. 1
OFF ON
OFF ON
JP1 (COOL
ONLY)
5 Message
Pump down operation in progress
3 minutes before operation end
2 minutes before operation end
1 minute before operation end
Pump down operation end
SW5 (MODE PRIORITY)
SW4 (POWER SAVE)
SW1 (PUMP DOWN)
SW2 (OPERATION TEST)
SW3 (WIRING CHECK)
Unit A Unit B
Unit D
51
Unit C
Hexagonal
wrench
Gas shut-off valve
Liquid shut-off valve
Close
Valve lid