Thermistor Or Related Abnormality (Outdoor Unit) - Daikin 2MXS40H2V1B Service Manual

Troubleshooting for Outdoor Unit

7.15 Thermistor or Related Abnormality (Outdoor Unit)

H9 , J3 , J6 , J8 , J9 , P4
Error Code
Method of Error This type of error is detected by checking the thermistor input voltage to the microcomputer.
A thermistor error is detected by checking the temperature sensed by each thermistor.
Detection
Error Decision
Conditions
Supposed
Causes
In case of " P4 "
Troubleshooting
Replace the outdoor unit PCB.
P4
199
The thermistor input is above 4.98 V or below 0.02 V with the power on.
J3
error is judged if the discharge pipe temperature is lower than the heat exchanger
temperature.
The system is shut down if all the units are judged as the J8 or J9 error.
Disconnection of the connector for the thermistor
Defective thermistor corresponding to the error code
Defective heat exchanger thermistor in the case of J3 error (outdoor heat exchanger
thermistor in cooling operation, or indoor heat exchanger thermistor in heating operation)
Defective outdoor unit PCB
Be sure to turn off the power switch before connecting or disconnecting
Caution
connectors, or parts may be damaged.
: Radiation fin thermistor
SiBE121123_A
Service Diagnosis