GREE ELECTRIC GWHDND3EO Service Manual page 40

All the indoor units appear
communication malfunction
De-energize,check if the connection
wire of indoor and outdoor unit and
the wire of the eletric box is
connected correctly
Connected correctly?
yes
De-energize, check if the connection wire between
the outdoor mainboard and the filter board
according to the wiring diagram
Connected correctly?
yes
The connection wire is broken?
no
Check if there is power input
bewtween the netrual wire and live
wire of the outdoor mainboard
There is power input?
yes
Replace the outdoor
mainboard
Resume communication?
yes
End
38
no
Reconnect according to
the wiring diagram
Reconnect according to
no
the wiring diagram
yes Replace the
connection wire
no
Replace the filter board of
the outdoor unit
no
Replace indoor
mainboard
Eliminate the malfunction
yes
Eliminate the malfunction
no
yes
Eliminate the malfunction
no
yes
Eliminate the malfunction
no
Installation and Maintenance
Service Manual
yes