Thermistor Or Related Abnormality - Daikin CTXG09QVJUW Service Manual

Troubleshooting for FFQ Series
6.5

Thermistor or Related Abnormality

C4 , C5 , C9
Error Code
Method of Error The temperatures detected by the thermistors determine thermistor errors.
Detection
Error Decision The thermistor is disconnected or shorted while the unit is running.
Conditions
Supposed
Causes
Troubleshooting If the cause of the problem is related to the thermistors, the thermistors should be checked prior to
changing the indoor unit PCB.
Check No.01
To check the thermistors, proceed as follows:
Refer to P.190
C4
C5
C9
Note: When replacing the defective thermistor(s), replace the thermistors as ASSY.
152
Disconnection of connector
Defective thermistor(s)
Breaking of wires
Defective indoor unit PCB
Step Action
1 Disconnect the thermistor from the indoor unit PCB.
2 Read the temperature and the resistance value.
Check if the measured values correspond with the values in the table of thermistor
3
resistance check.
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Check the connection of
connectors.
Normal?
YES
Check No. 01
Check the thermistor resistance
value.
Normal?
YES
: Indoor heat exchanger thermistor 1 (liquid pipe) (R2T)
: Indoor heat exchanger thermistor 2 (R3T)
: Room temperature thermistor (R1T)
NO
NO
SiUS121632EA
Correct the connection.
Replace the defective
thermistor(s).
Replace the indoor unit PCB
(control PCB).
(R24056)
Service Diagnosis