Thermistor Or Related Abnormality (Indoor Unit) - Daikin FTXS09HVJU Service Manual

Troubleshooting
4.5

Thermistor or Related Abnormality (Indoor Unit)

C4, C9
Remote
Controller
Display
Method of The temperatures detected by the thermistors are used to determine thermistor errors.
Malfunction
Detection
Malfunction When the thermistor input is more than 4.96 V or less than 0.04 V during compressor operation.
 (reference)
Decision
When above about 414°F (212°C) (less than 120 ) or below about –58°F (–50°C) (more than
Conditions
1,860 k).
Note: The values vary slightly in some models.
 Faulty connector connection
Supposed
 Faulty thermistor
Causes
 Faulty PCB
Troubleshooting
Check No.06
Refer to P.146
C4 : Heat exchanger thermistor
C9 : Room temperature thermistor
Service Diagnosis
Be sure to turn off the power switch before connecting or disconnecting
Caution
the connector, or parts damage may occur.
Check the connector connection.
Is it normal?
YES
Check No. 06
Check the thermistor resistance
value.
Is it normal?
YES
NO
NO
SiUS04-904
Correct the connection.
Replace the thermistor.
(Replace the indoor unit PCB.)
Replace the indoor unit PCB.
(R7134)
105