Carrier 38MGRBQ18B-3 - DIAGNOSIS AND SOLUTION (CONT); High Temperature Protection of Compressor Top

38MGRBQ: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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DIAGNOSIS AND SOLUTION (CONT)
High temperature protection of compressor top (IDU P2/ODU P0/PC 02)
Troubleshooting
ERROR CODE
P2/ODU P0/PC 02
MALFUNCTION DECISION
CONDITIONS
If the sampling voltage is not 5V, the LED displays the failure.
SUPPOSED CAUSES
Wiring mistake
Faulty overload protector
System leak or block
Faulty PCB
Check if the air flow system
of indoor and outdoor units
are obstructed
Clear up the air inlet and outlet or the heat
exchanger of indoor and outdoor units.
Yes
No
Yes
Yes
Turn of f the power supply and tur n
back on 10 minutes later
Check if the compressor top
temperature is higher than
194°F(90°C)
No
Check if the refrigerant
system is normal.
Repair the refrigerant
system
Replace the outdoor control PCB
Yes
Check if all the connections,
especially the OLP connection
(Over Load Protector) sensor is good.
Correct the connection.
No
Yes
Replace the OLP
No
Replace the outdoor control PCB.Yes
No
Measure the resistance
betwwen the two OLP ports.
Is it zero?