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SiBE18-821_C
Troubleshooting for BP Unit
Troubleshooting
379
6.4
Transmission Error between Indoor Unit and BP Unit
Outdoor Unit
Indication
U4
Method of
Malfunction
Detection
The data received from the BP unit in signal transmission is checked whether it is normal.
Malfunction
Decision
Conditions
When the data sent from the BP unit cannot be received normally, or when the content of the
data is abnormal.
Supposed
Causes
Defective BP unit PCB
Defective indoor unit PCB
Signal transmission error due to wiring error
Signal transmission error due to disturbed power supply waveform
Signal transmission error due to breaking of connection wires (wire No. 2).