Troubleshooting
DAMA-SM-21-001
79
Service Diagnosis
4.19 Thermistor or Related Abnormality (Outdoor Unit)
Error Code
H9, J3, J6 and P4
Description
Thermistor or Related Abnormality (Outdoor Unit)
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 both ends of the thermistor is either 4.96 V or more, or 0.04 V or less
with the power on.
J3
error is judged if the discharge pipe temperature is lower than the heat exchanger
temperature.
Possible Root
Causes
Disconnection of the connector for the thermistor
Defective thermistor(s)
Defective outdoor heat exchanger thermistor in the case of
J3
error
Defective outdoor unit PCB
Troubleshooting
In case of
P4
(Radiation fin thermistor)
Be sure to turn off the power switch before connecting or disconnecting connectors, or parts
may be damaged.
Replace the outdoor unit PCB (main PCB)
Troubleshooting
In case of
H9, J3, J6 and P4
Be sure to turn off the power switch before connecting or disconnecting connectors, or parts
may be damaged.
H9
: Outdoor temperature thermistor
Caution
Caution
Error displayed
again on remote
controller?
Indoor heat
exchanger thermistor
functioning?
Check the indoor heat exchanger
thermistor resistance value in the
heating operation.
Check the thermistor resistance value.
Normal?
No
Yes
Yes
Yes
No
Turn on the power again.
Replace the outdoor unit PCB.
Reconnect the connectors
or thermistors
No
J3 error: the discharge
pipe temperature is
lower than the heat
exchanger temperature.
Cooling : Outdoor heat
exchanger
temperature.
Heating : Indoor heat
exchanger
temperature.
Replace the defective
thermistor(s) of the following
thermistors.
• Outdoor temperature
thermistors.
• Discharge pipe thermistor.
• Outdoor heat exchanger
thermistor.
Replace the indoor heat
exchanger thermistor.
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
Caution
Summary of Contents for FTK Series
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