Four Way Valve Abnormality - Daikin FTX-N Series Service Manual

SiUS041638EA

4.15 Four Way Valve Abnormality

EA
Error Code
Method of Error
The room temperature thermistor and the indoor heat exchanger thermistor are checked if they
Detection
function within their normal ranges in each operation mode.
Error Decision
The following condition continues over 10 minutes after operating for 5 minutes.
Conditions  Cooling/Dry
 Heating
 If the error repeats, the system is shut down.
 Reset condition: Continuous run for about 60 minutes without any other error
Supposed
 Disconnection of four way valve coil
Causes
 Defective four way valve, coil, or harness
 Defective outdoor unit PCB
 Defective thermistor(s)
 Refrigerant shortage
 Water mixed in refrigerant
 Defective stop valve
Service Diagnosis
A – B < –5°C (A – B < –9°F)
B – A < –5°C (B – A < –9°F)
A: Room thermistor temperature
B: Indoor heat exchanger temperature
Troubleshooting
78