47
Installation and Maintenance
Service Manual
2.IPM protection, desynchronizing malfunction, phase current of compressor is overcurrent (AP1 below is control board
of outdoor unit)
Main detection point:
● If control board AP1 and compressor COMP is well connected? If they are loosened? If the connection sequence is correct?
● Is voltage input in the normal range (Test the voltage between L, N of wiring board XT by DC voltage meter)?
● If coil resistance of compressor is normal? Is compressor coil insulating to copper pipe well?
● If the work load of unit is heavy? If radiating of unit is well?
● If the refrigerant charging is appropriate?
Malfunction diagnosis process:
