GREE                                                                        GMV5E DC INVERTER VRF UNITS SERVICE MANUAL 
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Part 2 Exception and Troubleshooting 
2 Exception Analyzing and Troubleshooting 
2.1 Form analyzing 
2.1.1 Control 
Faults in the ODU's 
main board (such 
as memory and 
address chip 
exceptions) 
1.The clock chip on the main 
board is damaged. 
2.The memory chip on the main 
board is damaged. 
3.The address chip on the main 
board is damaged. 
1.Replace the small CPU board. 
2.Replace the control board. 
3.Replace the control board. 
Faults in the 
constant frequency 
compressor's 
current sensor 
1.The constant-frequency 
compressor is not started. 
2.The current detection board is 
faulty. 
3.The main board's detection 
circuit is faulty. 
1.If the compressor is not started, check if the AC 
contact is closed. If not, replace the AC contact.   
If the connection is loose, reconnect it;   
2.Replace the current detection board.   
3.Replace the main board.   
Wrong outdoor 
capacity code 
setting 
1.The capacity code is wrong. 
2.The dial component is faulty. 
1.Modify the capacity code setting. 
2.Replace the main board.   
Power phase 
sequence 
protection 
1.The three-phase power cable is 
not connected correctly. 
2.The main board's detection 
circuit is faulty. 
1.Check connection of the power cable. 
2.Replace the control board.   
Wrong emergency 
operation dial code 
1.The dial setting is wrong. 
2.The dial component is faulty. 
1.Modify the dial setting. 
2.Replace the main board.   
Communication 
failure between 
indoor and ODUs 
and IDU's 
communicator 
1.The communication cable is not 
connected. 
2.The communicator is 
disconnected. 
3.The communication cable is 
poorly connected. 
4.The communicator controller is 
faulty. 
If C0 is not displayed on the control board of the 
ODU, check the network between the IDU and 
communicator. If C0 is displayed, check the 
network between the IDUs and ODUs and 
between the IDU and communicator as follows: 
1)Check if the cables connecting the control board 
of the ODU and the IDU and connecting the IDU 
and communicator are loose. If yes, reconnect them; 
2)Check if the cables connecting the control board 
and IDU and connecting the IDU and 
communicator are broken. If yes, replace the 
cables;   
3)Check the contact of the communication cables;   
4)Replace the control board. If the fault is solved, 
the control board is faulty. Replace the IDU. If the 
fault is solved, the IDU is faulty.   
Communication 
failure between 
main control board 
and inverter 
compressor drive 
1.The communication cable is not 
connected. 
2.The communicator is 
disconnected. 
3.The communication cable is 
poorly connected. 
4.The communicator is faulty. 
1)Check if the cable connecting the control board 
and the compressor's drive board is loose. If yes, 
reconnect it; 
2)Check if the cable connecting the control board 
and compressor's drive board is broken. If yes, 
replace the cable;   
3)Check the contact of the communication cable 
connecting the control board and compressor's 
drive board;   
4)Replace the control board. If the fault is solved, 
the control board is faulty. Replace the