Error code:
P0
Reason:
If the power supply to the compressor controller is faulty, the display shows the error code
“P0” and the unit switches off
Cause:
n
Electrical connection faulty
n
Faulty control board
n
Condenser fan motor defective or blocked
n
Compressor defective
Check the connecting cables between the con-
trol board and compressor? Are they faulty?
YES
Establish a correct connection between the
control board and compressor.
NO
Check the inverter controller (see section
‘Check the inverter controller’ on page 53
).
Error rectified?
NO
Replace the control board.
YES
Check the condenser fan motor. Is it working
correctly?
NO
See troubleshooting fault F5
YES
Check the winding resistances of the com-
pressor. Are they OK?
NO
Replace the compressor.
YES
Exchange the control boards of the outdoor
unit.
Check the inverter controller
Switch off the power supply to the unit. Wait until the capacitors are fully discharged and disconnect the com-
pressor from the control board.
Check the resistances at the outputs of the control board with the aid of a digital voltmeter as follows:
ML 265 DC
ML 355 DC
ML 525 DC
ML 685 DC
blue - red
1.57
W
(20°C/68°F)
1.82
W
(20°C/68°F)
1.72
W
(20°C/68°F)
0.75
W
(20°C/68°F)
blue - black
red - blue
53