Panasonic WH-UD28AE Service Manual page 63

16.5.21. IPM Overheating (F96)
Malfunction Decision Conditions:
During operation of heating, temperature 95°C is detected by the outdoor IPM temperature sensor.
Malfunction Caused:
1. IPM overheat due to short circuit of hot discharge air flow.
2. IPM overheat due to defective of outdoor fan motor.
3. IPM overheat due to defective of internal circuitry of IPM.
4. IPM overheat due to defective IPM temperature sensor.
Abnormality Judgment:
Continue 3 times in 30 minutes.
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