Insufficient Gas - Daikin ATXS35EV1B7 Service Manual

Troubleshooting
4.24

Insufficient Gas

4.24.1 25/35 Class
U0
Remote
Controller
Display
Method of Gas shortage detection I:
Gas shortage is detected by checking the input current value and the compressor running
Malfunction
frequency. If the gas is short, the input current is smaller than the normal value.
Detection
Gas shortage detection II:
Gas shortage is detected by checking the discharge temperature and the opening of the
electronic expansion valve. If the gas is short, the discharge temperature tends to rise.
Gas shortage detection III:
A gas shortage is detected by checking the difference between inhale and exhale temperature.
Malfunction Gas shortage detection I:
The following conditions continue for 7 minutes.
Decision
Conditions
Gas shortage detection II:
The following conditions continue for 80 seconds.
Gas shortage detection III:
When the difference of the temperature is smaller than
Cooling
Heating
If a gas shortage error takes place 4 times straight, the system will be shut down. The error
counter will reset itself if this or any other error does not occur during the following 60-minute
compressor running time (total time).
Supposed
Causes
122
Input current × input voltage
Output frequency > 55 (Hz)
Target opening of the electronic expansion valve ≥ 480 (pulse)
Discharge temperature > 255 / 256 × target discharge temperature +30 (°C)
room temperature – indoor heat exchanger temperature
outdoor heat exchanger temperature – outdoor temperature
indoor heat exchanger temperature – room temperature
outdoor temperature – outdoor heat exchanger temperature
Refrigerant shortage (refrigerant leakage)
Poor compression performance of compressor
Discharge pipe thermistor disconnected, or indoor unit or outdoor unit heat exchanger
thermistor disconnected, room or outdoor air temperature thermistor disconnected
Stop valve closed
Electronic expansion valve defective
≤
640 / 256 × output frequency
SiBE04-824
, it is regarded as insufficient gas.
4.0°C
4.0°C
3.0°C
3.0°C
Service Diagnosis