Thermistor Or Related Abnormality (Indoor Unit) - Daikin CTXU25G2V1B Service Manual

Troubleshooting

2.10 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 ∗ .
Decision
∗
Conditions
When above about 212°C (less than 120 Ω ) or below about –50°C (more than 1,860 k Ω ).
Note: The values vary slightly in some models.
Supposed
Causes
Troubleshooting
Check No.02
Refer to P.169
Check the connector connection.
C4
C9
125
(reference)
Faulty connector connection
Faulty thermistor
Faulty PCB
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Caution
Is it normal?
YES
Check No.02
Check the thermistor resistance
value.
Is it normal?
YES
: Heat exchanger thermistor
: Room temperature thermistor
NO
NO
SiBE12-908
Correct the connection.
Replace the thermistor.
(Replace the indoor unit PCB.)
Replace the indoor unit PCB.
(R9466)
Service Diagnosis