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Troubleshooting for Outdoor Unit
SiUS121632EA
184
Service Diagnosis
7.17 Thermistor or Related Abnormality (Outdoor Unit)
Error Code
H9
,
J3
,
J6
,
J8
,
J9
,
P4
Outdoor Unit LED
Display
A
j
1
i
2
i
3
h
4
h
5
h
Method of Error
Detection
This fault is identified based on the thermistor input voltage to the microcomputer.
A thermistor fault is identified based on the temperature sensed by each thermistor.
Error Decision
Conditions
The voltage between the both ends of the thermistor is above 4.96 V or below 0.04 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
error.
Supposed
Causes
Disconnection of the connector for the thermistor
Thermistor corresponding to the error code is defective.
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
Troubleshooting
In case of
P4
Replace the outdoor unit PCB (main PCB).
P4
: Radiation fin thermistor
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.