Troubleshooting
SiUS091133
119
Service Diagnosis
4.16 FourWay Valve Abnormality
Remote
Controller
Display
EA
Method of
Malfunction
Detection
The room temperature thermistor and the indoor heat exchanger thermistor are checked if they
function within their normal ranges in each operation mode.
Malfunction
Decision
Conditions
A following condition continues over 1 ~ 10 minutes after operating for 5 ~ 10 minutes.
Cooling / Dry
(room thermistor temp. – indoor heat exchanger temp.) < –5°C (–9°F)
Heating
(indoor heat exchanger temp. – room thermistor temp.) < –5°C (–9°F)
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 fourway valve coil
Defective fourway valve, coil, or harness
Defective outdoor unit PCB
Defective thermistor
Refrigerant shortage
Water mixed in refrigerant
Defective stop valve
