Insufficient Gas - Daikin FTXS30HVJU Service Manual

Troubleshooting

4.23 Insufficient Gas

U0
Remote
Controller
Display
Method of
Gas shortage detection I :
Malfunction A gas shortage is detected by checking the CT-detected input current value and the compressor
running frequency.
Detection
Gas shortage detection II :
A gas shortage is detected by checking the difference between 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 :
DC current 
Decision
However, when the status of running frequency > 40 (Hz) is kept on for a certain time.
Conditions
Note : The values are different from model to model.
30/36 class
Gas shortage detection II :
Electronic expansion valve opening
Discharge pipe temperature(°C)
30/36 class
If a gas shortage error takes place 4 times successively, 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).
 Refrigerant shortage (refrigerant leakage)
Supposed
 Poor compression performance of compressor
Causes
 Discharge pipe thermistor disconnected, or indoor unit or outdoor unit heat exchanger
 Stop valve closed
 Electronic expansion valve defective
102
(A/Hz) Output frequency +
27 / 1000
480
thermistor disconnected, room or outside air temperature thermistor disconnected
2
 
(pulse)

target discharge pipe temperature(°C) +
128/128 Cooling: 50, Heating: 45
SiUS04-924
(°C)
Service Diagnosis