Insufficient Gas - Daikin FT25CV1A Service Manual

Si01-406
Insufficient Gas (U0)
4.18
U0
Remote
Controller
Display
Method of Gas shortage detection I : A gas shortage is detected by checking the CT-detected input current
value and the compressor running frequency.
Malfunction
Gas shortage detection II : A gas shortage is detected by checking the difference between
Detection
indoor unit heat exchanger temperature and room temperature as well as the difference
between outdoor unit heat exchanger temperature and room temperature.
Malfunction Gas shortage detection I :
Input current < 1400 ✕ 256 (A/Hz) ✕ Compressor running frequency ✕ Voltage +180
Decision
However, when the status of running frequency > 62 (Hz) is kept on for a certain time.
Conditions
Note : The values are different from model to model.
Supposed
Causes
Service Diagnosis
Refrigerant shortage (refrigerant leakage)
Poor compression performance of compressor
Indoor unit or outdoor unit heat exchanger thermistor disconnected, room or outdoor air
temperature thermistor disconnected
Stop valve closed
Troubleshooting
113