Daikin AT12BV1LS Pocket Manual page 128

Si10-417
5.3.2 Insufficient Gas
Remote
Controller
Display
Method of
Malfunction
Detection
Malfunction
Decision
Conditions
Supposed
Causes
Service Diagnosis
U0
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.
Gas shortage detection I :
Input current <
frequency × Voltage +
However, when the status of running frequency > 55
(Hz) is kept on for a certain time.
Note : The values are different from model to model.
R410A
R22
RXD71BVMA
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).
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 outside air temperature
thermistor disconnected
Stop valve closed
Electronic expansion valve defective
(A/Hz) x Compressor running
1756 / 256
2600 / 256
2420 / 256
Troubleshooting
–50
–300
55
127