Gree GWH07AA-K3DNA1B/I Service Manual page 50

Communication malfunction of
some indoor units
De-energize the unit and check
if the connecting wire of indoor
and outdoor unit and wiring of
electric box are correct.
Yes
Connect wires
No
Is malfunction
Is wire connected
according to the
removed
correctly
wiring diagram
Yes No
De-energize the unit. Change the communication cable
of indoor units. Energize the unit and wait for 3 min
Does the
Yes
Replace mainboard
broken-down indoor
of outdoor unit
unit resume normal?
No
Replace the broken-down
mainboard of the indoor unit
End