Panasonic CS-RE18QKE Service Manual page 58

15.5.7 H23 (Indoor Pipe Temperature Sensor Abnormality)
Malfunction Decision Conditions

During startup and operation of cooling and heating, the temperatures detected by the indoor heat exchanger
temperature sensor are used to determine sensor errors.
Malfunction Caused

Faulty connector connection.

Faulty sensor.

Faulty PCB.
Troubleshooting
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