Panasonic CS-PS9JKT, Service Manual

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53
14.4.10 H28 (Outdoor Pipe Temperature Sensor Abnormality)
Malfunction Decision Conditions
•
During startup and operation of cooling and heating, the temperatures detected by the outdoor pipe 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
Is the measured resistance of the outdoor heat exchanger
temperature sensor matches the value specified in its
characteristic chart?
YES
When abnormality indication starts again
Check the outdoor heat exchanger temperature sensor:
•
Plug out connector from the outdoor unit PCB
•
Measure the resistance of the outdoor heat exchanger
temperature sensor
•
Defect in outdoor heat exchanger
temperature sensor
•
Replace the outdoor heat exchanger
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?
•
Connector poor contact
•
Correct the connection
No
YES
No