Thermistor Or Related Abnormality (Outdoor Unit) - Daikin H Series Service Manual

Troubleshooting

4.19 Thermistor or Related Abnormality (Outdoor Unit)

H9, J3, J6, P4
Remote
Controller
Display
Method of
This fault is identified based on the thermistor input voltage to the microcomputer.
Malfunction A thermistor fault is identified based on the temperature sensed by each thermistor.
Detection
 The thermistor input voltage is above 4.96 V or below 0.04 V with the power on.
Malfunction
 J3 error is judged if the discharge pipe temperature is lower than the heat exchanger
Decision
Conditions
 Disconnection of the connector for the thermistor
Supposed
 Defective thermistor corresponding to the error code
Causes
 Defective heat exchanger thermistor in the case of J3 error (outdoor heat exchanger thermistor
 Defective outdoor unit PCB
 Defective indoor unit PCB
Troubleshooting
In case of "P4"
Replace the outdoor unit PCB.
P4 : Radiation fin thermistor
Service Diagnosis
temperature.
in cooling operation, or indoor heat exchanger thermistor in heating operation)
Be sure to turn off the power switch before connecting or disconnecting
Caution
connectors, or parts may be damaged.
SiUS04-924_A
97