Sinclair SCV-1400EB, Service Manual

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5.12 P4, P5 Troubleshooting
Digital display output
Description
 1 P4 indicates system A current protection

2 P4 indicates system A DC bus current protection

1 P5 indicates system B current protection

2 P5 indicates system B DC bus current protection

When the compressor current rises above the protection value 33A, the system displays P4 or P5 protection and all units
stop running. When the current returns to the normal range, P4 or P5 is removed and normal operation resumes. When P4
or P5 error occurs 3 times in 60 minutes, a manual system restart is required before the system can resume operation.

Error code is displayed on main PCB and user interface.
Possible causes
 Power supply abnormal.

Poor condenser heat exchange.

High pressure side blockage.

Excess refrigerant.

System contains air or nitrogen.
 Inverter module damaged.

Compressor damaged.

Main PCB damaged.