GREE ELECTRIC GWHDND3EO Service Manual page 39

Service Manual
8. Communication malfunction
Main checking points:
If the connection wire between the indoor unit and outdoor unit is connected well, if the wires inside the unit is connected well;
If the indoor mainboard or outdoor main board is broken;
Flow chart:
Communication malfunction of some
De-energize,check if the connection
wire of indoor and outdoor unit and
the wire of the eletric box is
connected correctly
Connected correctly
De-energize, change the communication wire of the well-
communicated indoor unit and malfunction indoor unit,
then energize the unit and wait for 3min
The malfunction indoor unit
Replace the mainboard of the
malfunction indoor unit
Installation and Maintenance
indoor units
no
yes
yes
resumes normal
no
End
Reconnect according to
the wiring diagram
Replace outdoor
mainboard
yes
Eliminate the malfunction
no
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