Panasonic WH-MHF12G9E8 Service Manual page 93

16.5.5 Service Valve Error (H27)
Malfunction Decision Conditions:
During cooling operation, when:-
[a] Indoor refrigerant pipe temperature at compressor startup - present indoor refrigerant pipe temperature < 2°C
[b] Present high pressure - high pressure at compressor startup < 5kg/cm²
**Judgment only for first time cooling operation and not during pump down operation.
Malfunction Caused:
1 3 way valves closed.
2 Faulty high pressure sensor.
3 Faulty indoor refrigerant pipe temperature sensor
4 Faulty outdoor unit PCB (main).
Abnormality Judgment:
Continue for 5 minutes.
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