Panasonic CS-YE18NKV-6 Service Manual page 62

15.5.13 H98 (Indoor High Pressure Protection)
Error Code will not display (no Timer LED blinking) but store in EEPROM
Malfunction Decision Conditions

During heating operation, the temperature detected by the indoor pipe temperature sensor is above 60°C.
Malfunction Caused

Clogged air filter of the indoor unit

Dust accumulation on the indoor unit heat exchanger

Air short circuit

Detection error due to faulty indoor pipe temperature sensor

Detection error due to faulty indoor unit PCB
Troubleshooting
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