Gree GMV-1015WM/G-U, Service Manual

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Gree GMV6 DC Inverter VRF Units Service Manual
98
Step 1: for the mode exchanger with several main boards, please check if error is reported for every main
board, if no, please make sure at least one branch is connected with IDU under the main board of every mode
exchanger;
Step 2: check the terminal between mode exchanger main board and IDU to see if it is loose or any foreign
objects inside? If yes, reconnect it after treatment;
Step 3: check if the communication cord between mode exchanger and IDU is damaged or short-connected,
if yes, please replace it;
Step 4: if the above inspections are normal, the detecting circuit might be abnormal, please replace the mode
exchanger main board and IDU main board in turn; then replace the main board after confirming the faulted board.
2.43 "CF" Multi-master Units Fault
Fault display: main board of outdoor unit, wired controller of indoor unit and receiver of indoor unit
display
Fault diagnosis:
The main board detects the master DIP switch (SA8) and determines whether it is the master.
When multiple master units are detected in the multi-module communication network, the fault is
generated.
Possible causes:
■ The master DIP switch is abnormal and multiple master units exist in the network;
■ Abnormal detection circuit.
Troubleshooting:
No
"CF" Multi-master Units
Fault
Make sure that only one master
unit exists in the network. After
redialing, power on the redialed
modules again
The main control board
may be abnormal
Yes
Replace the main control
board
Yes
Whether DIP switch is dialed
properly for the master unit (SA8)
among all the modules in
the network?
2.44 "CJ" System Address Code Conflict
Fault display: main board of outdoor unit, wired controller of indoor unit and receiver of indoor unit
display
Fault diagnosis:
When multiple refrigerant systems are connected through the CAN2 network of the unit's main board,
only one primary system is allowed in the network.
If two or more master units' DIP switches (SA2) are detected to be master unit's DIP switches in the
network (that is, SA2 DIP switch is "00000"), the fault of multiple master units is reported.