Sinclair SYMPHONY MS-H09AISW PT Service Manual page 34

Communication malfunction of
all indoor units
De-energize the unit and check if the
connecting wire of indoor and outdoor unit
and wiring of electric box are correct.
Is wire connected
correctly
Yes
De-energize the unit. Check if the connecting wire
between outdoor mainbaord and filter plate is correct.
Is wire connected
correctly
Yes
Is connecting wire
damaged
No
Check if there is power input between
neutral wire and live wire of outdoor unit.
Is there power
input?
Yes
Replace mainboard of outdoor unit
Does communication
resume normal
Yes
End
Connect wires
No
according to the
wiring diagram
Connect wires
No
according to the
wiring diagram
Yes
Replace the
connecting wire
No
Replace filter plate of
outdoor unit
No
Replace mainboard
of indoor unit
Yes
Is malfunction
removed
No
Yes
Is malfunction
removed
No
Yes
Is malfunction
removed
No
Yes
Is malfunction
removed
No
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