Panasonic WH-UD30BE5-1 Service Manual page 60

16.5.17. Refrigeration Cycle Abnormality (F24)
Malfunction Decision Conditions:
1. During operation of heating, compressor frequency > Fhrated.
2. During operation of heating, running current: 0.65A < I < 1.65A.
3. During operation of heating, indoor pipe temperature — water inlet temperature < 5°C.
Malfunction Caused:
1. Faulty indoor water inlet or indoor pipe temperature sensors.
2. 2/3 way valve closed.
3. Refrigerant shortage (refrigerant leakage).
4. Clogged expansion valve or strainer.
5. Faulty outdoor unit PCB.
6. Poor compression of compressor.
Abnormality Judgment:
Continue 2 times in 20 minutes.
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