Service Manual

Troubleshooting SiUS091133
105 Service Diagnosis
Refrigerant shortage detection III: (09/12 class only)
When the difference of the temperature is smaller than L, it is regarded as refrigerant shortage.
 If the error repeats, the system is shut down.
 Reset condition: Continuous run for about 60 minutes without any other error
Supposed
Causes
 Disconnection of the discharge pipe thermistor, indoor or outdoor heat exchanger thermistor,
room or outdoor temperature thermistor
 Closed stop valve
 Refrigerant shortage (refrigerant leakage)
 Poor compression performance of compressor
 Defective electronic expansion valve
L
Cooling
room thermistor temperature – indoor heat exchanger temperature 4.0°C (7.2°F)
outdoor heat exchanger temperature – outdoor temperature 4.0°C (7.2°F)
Heating
indoor heat exchanger temperature – room thermistor temperature 3.0°C (5.4°F)
outdoor temperature – outdoor heat exchanger temperature 3.0°C (5.4°F)