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Self-diagnosis function
n
Error diagnosis and countermeasure flow chart
1. Bad connection of air temperature connector
2. Defect of air temperature connector(Open/Short)
3. Defect of outdoor PCB
1. Bad connection of air temperature connector
2. Defect of air temperature connector(Open/Short)
3. Defect of outdoor PCB
1. Bad connection of air temperature connector
2. Defect of air temperature connector(Open/Short)
3. Defect of outdoor PCB
Error No.
Error Type
Error Point
Main Reasons
Abnormal value of
sensor (Open/Short)
Abnormal value of
sensor
(Open/Short)
Abnormal value of
sensor (Open/Short)
Sensor error of
outdoor air temper-
ature
Piping temperature
sensor error of heat
exchanger in
master & slave out-
door unit heat
exchanger (A,B)
Compressor suc-
tion temperature
sensor error
44
46
45
Is sensor connected
to PCB correctly??
Is sensor value correct?*
Connect sensor to PCB correctly
Replace sensor
Replace corresponding
outdoor unit PCB
Yes
No
No
Yes
* If value is 100 kΩ
↑
(open) or 100 Ω
↓
(short), error occurs
NB: Resistance value of temperature sensor change according to
temperature
It is normal if value shown as below (±5 % error)
Sensor of air temperature: 10 °C = 20.7 kΩ : 25 °C= 10 kΩ : 50 °C= 3.4 kΩ
Sensor of piping temperature: 10 °C = 10 kΩ : 25 °C= 5 kΩ : 50 °C= 1.8 kΩ