Daikin FTKS20D2VMWL, Service Manual

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SiENBE04-507A Troubleshooting
Service Diagnosis 133
4.19 Thermistor or Related Abnormality (Outdoor Unit)
Remote
Controller
Display
P4, J3, J6, H9
Method of
Malfunction
Detection
This type of error is detected by checking the thermistor input voltage to the microcomputer.
[A thermistor error is detected by checking the temperature.]
Malfunction
Decision
Conditions
The thermistor input is above 4.96 V or below 0.04 V with the power on.
Error
J3
is judged if the discharge pipe thermistor temperature is smaller than the condenser
thermistor temperature.
Supposed
Causes
„ Connector in poor contact
„ Thermistor defective
„ Outdoor unit PCB defective
„ Indoor unit PCB defective
„
Condenser thermistor defective in the case of
J3
error (outdoor unit heat exchanger
thermistor in the cooling mode, or indoor unit heat exchanger thermistor in the heating
mode)