Panasonic CS-MS9SD3H Service Manual page 50

13.5.8 H24 (Indoor Pipe Temperature Sensor 2 Abnormality)
Malfunction Decision Conditions

During startup and operation of cooling, the temperatures detected by the indoor heat exchanger temperature
sensor 2 are used to determine sensor errors.
Malfunction Caused

Faulty connector connection.

Faulty sensor.

Faulty PCB.
Troubleshooting
When abnormality indication starts again
Check the connector connection:
● Plug out connector from the indoor unit PCB
● Measure the resistance of the indoor pipe temperature
sensor
Is the connector connection normal?
Check the outdoor air temperaturesensor:
● Plug out connector from the outdoor unit PCB
● Measure the resistance of the outdoor intake air
temperature sensor
Is the measured resistance of the outdoor intake air
temperature sensor matches the value specified in its
characteristic chart?
Sensor (Thermistor)
Characteristics
70
1 Pipe temp. Sensor 1 & 2
60
2 Intake Air Temp. Sensor
50
1
40
2
30
20
10
0
-10 0 10 20
Temperature (ºC)
YES
YES
30 40 50
For safety reason and to prevent component
breakdown, always switch off the power
Caution
before remove and connect the component.
● Connector poor contact
NO
● Correct the connection
●
Defect in outdoor intake air temperature sensor
NO
● Replace the outdoor intake air temperature
sensor
●
Defect in outdoor unit PCB
● Replace the outdoor unit PCB
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