Troubleshooting Guide

8.4.2.12 P4 (Temperature protection of compressor discharge) diagnosis and solution.
Error Code P4
Malfunction decision
conditions
When the compressor discharge temperature(T5) is more
than 115℃ for 10 seconds, the compressor will stop and
restart till T5 is less than 90℃.
Supposed causes
● Refrigerant leakage
● Wiring mistake
● The discharge temperature sensor faulty
● Outdoor PCB faulty
Trouble shooting:
Temperatureprotectionof
compressordischarge
Checkwhetherthe
compressordischargetemp.is
morethan115°C?
Check whether the
connection is right between
compressor discharge temp.
sensor and PCB according
to wiring diagrams?
Measure the resistance value
of compressor discharge
temp. sensor. If the value is
not normal isnormal referto
theAppendix 2?
No
Yes
Yes
No
Correct the wiring connection
Stopleakingandaddrefrigerant
Replace the compressor discharge temp. sensorNo
Yes
Replace high pressure valve assy
Yes
No
Replace outdoor main PCB
No
Checkwhetherthe
refrigerantisleak
8.4.2.13 P5 (High temperature protection of condenser) diagnosis and solution.