Service Manual

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