Panasonic WH-UD28AE Service Manual page 57

16.5.15. Indoor Water Inlet Temperature Sensor Abnormality (H68)
Malfunction Decision Conditions:
During startup and operation of heating, the temperatures detected by the indoor water inlet temperature sensor are used to
determine sensor error.
Malfunction Caused:
1. Faulty connector connection.
2. Faulty sensor.
3. Faulty PCB.
Abnormality Judgment:
Continue for 5 seconds.
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