MXZ-SM36NAMHZ Service Manual

108
OCH789
Check code
Abnormal points and detection methods Causes and checkpoints
When the connected indoor unit is not compatible with the outdoor unit,
the outdoor unit detects the error at startup.
Connecting indoor unit(s) which is not authorized to
connect to the outdoor unit.
●Diagnosis of defects
Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards.
Diagnosis Remedy
7130
(EF)
Incompatible unit combination error
No
Is the indoor unit authorized to
connect with the outdoor unit?
Replace the indoor unit(s) to the one that
is compatible.
Refer to the service manual of the outdoor
unit or the connected indoor unit for the
authorized combination.
Yes
No
Yes
Check whether the model
selection switch is set correctly.
Are they correct?
Set the model selection switch correctly,
then restart.
Replace the outdoor controller board.