Panasonic Aquarea T-CAP R32 fault H27

What it means

During cooling operation, this error is triggered when: [a] Indoor refrigerant pipe temperature at compressor startup minus present indoor refrigerant pipe temperature is less than 3°C, AND [b] Present high pressure minus high pressure at compressor startup is less than 3kg/cm2. Judgment only applies for first time cooling operation and not during pump down operation.

Likely causes

1. High pressure sensor defective or disconnected
2. Faulty high pressure sensor
3. Faulty indoor refrigerant pipe temperature sensor
4. Excess insertion of refrigerant
5. Dirty condenser, attachment of impurity
6. Lack of refrigerant gas

Where to start

1. Check high pressure sensor wiring and continuity
2. If 3 way valve is not closed, check for clogged expansion valve or strainer (ice formed). If clogged: replace the expansion valve and/or strainer, and reclaim and recharge refrigerant.
3. If expansion valve/strainer not clogged, check the indoor refrigerant pipe temperature sensor against the sensor characteristic chart. If it does not conform: replace the indoor refrigerant pipe temperature sensor.