Current Protection Of Compressor Error (P3) - Carrier 38MGR Series Service Manual

DIAGNOSIS AND SOLUTION (CONT)

Current protection of compressor error (P3)

ERROR CODE
MALFUNCTION DECISION
CONDITIONS
SUPPOSED CAUSES
Troubleshooting
58
P3
If the outdoor current exceeds the current limit value, the LED displays the failure.
• Wiring mistake
• Over load protector faulty
• System block
• Outdoor PCB faulty
Current Compressor Protection
Judge 1: Check if the power
supply wire input current is more
than 12.5A (18K) For 24K it is 17.
For 30K, it is 18.5. For 36K, it is 23A.
,
Yes
Check if the refrigerant system
is working as designed.
Judge 2: Check if the
outdoor ambient temperature
is higher than 122° F.
No
Judge 3: Check whether the
outdoor unit's ventilation is poor.
No
Judge 4: Check if the
heat exchanger is dirty.
No
Judge 5: The refrigerant
pipe is blocked.
No
Replace the outdoor main board
and check whether the system
can run normally.
No
Replace the electric control box.
Specifications subject to change without notice.
Replace the outdoor main board.
No
Stop the unit.
Yes
Yes Resolve the ventilation issue.
Yes Clean the heat exchanger.
Let the refrigerant out, and then use the high
Yes
pressure nitrogen or refrigerant to blow the
pipe, vacuum, and charge the refrigerant again.
Yes
Yes Problem solved.
38MGR-04SM