Panasonic CS-PS9JKT, Service Manual

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52
14.4.9 H27 (Outdoor Air Temperature Sensor Abnormality)
Malfunction Decision Conditions
•
During startup and operation of cooling and heating, the temperatures detected by the outdoor air temperature
sensor are used to determine sensor errors.
Malfunction Caused
•
Faulty connector connection.
•
Faulty sensor.
•
Faulty PCB.
Troubleshooting
Sensor (Thermistor)
Characteristics
70
60
50
Res
is
tanc
e
(k
Ω
)
40
30
20
10
0
Temperature (ºC)
-10 0 10 20 30 40 50
1 Outdoor Air Sensor
2 Outdoor Heat Exchanger
Sensor
1
2
When abnormality indication starts again
Check the outdoor air temperature sensor:
•
Plug out connector from the outdoor unit PCB
•
Measure the resistance of the outdoor air temperature
sensor
Is the measured resistance of the outdoor air temperature
sensor matches the value specified in its characteristic
chart?
•
Defect in outdoor air temperature sensor
•
Replace the outdoor air temperature sensor
•
Defect in outdoor unit PCB
•
Replace the outdoor unit PCB
For safety reason and to prevent component
breakdown, always switch off the power
before remove and connect the component.
Check the connector connection:
•
Turn off the power
•
Check the connector connection
Is the connector connection normal?
YES
•
Connector poor contact
•
Correct the connection
NO
YES
NO