Four Way Valve Abnormality - Daikin FLKS25BVMB Service Manual

SiBE05-311

4.10 Four Way Valve Abnormality

EA
Remote
Controller
Display
Method of
The indoor air temperature thermistor, the indoor unit heat exchanger thermistor, the outdoor
Malfunction temperature thermistor and the outdoor unit heat exchanger thermistor are checked to see if
they function within their normal ranges in the operating mode.
Detection
Malfunction A following condition continues over 10 minute after operating 5 minutes.
Decision
Conditions
Supposed
Causes
Service Diagnosis
Cooling / dry operation
(room temp. – indoor heat exchanger temp.) < -10˚C
Heating
(indoor unit heat exchanger temp. – room temp.) < -10˚C
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
Troubleshooting
85