Troubleshooting
Si10-417
124
Service Diagnosis
5.3 System
5.3.1 Insufficient Gas
Remote
Controller
Display
U0
Method of
Malfunction
Detection
Gas shortage detection I : A gas shortage is detected by
checking the CT-detected input current value and the
compressor running frequency.
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
Decision
Conditions
Gas shortage detection I :
Input current <
(A/Hz) x Compressor running
frequency × V
However, when the status of running frequency
>
(Hz) is kept on for a certain time.
Note : The values are different from model to model.
Gas shortage detection II :
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).
Supposed
Causes
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
FTK(X)S,
ATK(X)S series.
1120 / 256
–80
65
Others
2760 / 256
–140
55
Si10-417.fm Page 124 Wednesday, September 22, 2004 6:38 PM
