Troubleshooting
Si10-417
60
Service Diagnosis
5.2.17 Four Way Valve Abnormality
Remote
Controller
Display
EA
Method of
Malfunction
Detection
The indoor air temperature thermistor, the indoor unit
heat exchanger thermistor, the outdoor temperature
thermistor and the outdoor unit heat exchanger
thermistor are checked to see if they function within their
normal ranges in the operating mode.
Malfunction
Decision
Conditions
A following condition continues over 10 minute after
operating 5 minutes.
Cooling / dry operation
(room temp. – indoor heat exchanger temp.) < -10°C
Heating
(indoor unit heat exchanger temp. – room temp.) < -10°C
Supposed
Causes
Connector in poor contact
Thermistor defective
Outdoor unit PCB defective
Four way valve coil or harness defective
Four way valve defective
Foreign substance mixed in refrigerant
Insufficient gas
Si10-417.fm Page 60 Wednesday, September 22, 2004 6:38 PM
