H99 (Indoor Freeze Prevention Protection: Cooling Or Soft Dry) - Panasonic CS-RE18PKR Service Manual

15.5.20 H99 (Indoor Freeze Prevention Protection: Cooling or Soft Dry)

Error Code will not display (no Timer LED blinking) but store in EEPROM
Malfunction Decision Conditions

Freeze prevention control takes place (when indoor pipe temperature is lower than 2°C).
Malfunction Caused

Air short circuit at indoor unit.

Clogged indoor unit air filter.

Dust accumulation on the indoor unit heat exchanger.

2/3 way valve closed.

Faulty indoor unit fan motor.

Refrigerant shortage (refrigerant leakage).

Clogged expansion valve or strainer.

Faulty indoor pipe temperature sensor.

Faulty indoor unit PCB.
Troubleshooting
91