Gree GMV5E Series Service Manual page 131

GREE
Fault
Fault
code
Communication
failure between
C3 main control board
and variable
frequency fan drive
Malfunction of lack
C4
of indoor unit
Indoor unit project
C5 number conflict
warning
Outdoor unit
number
C6
inconsistency
warning
CC No controlling unit
Multiple controlling
CF
units
L7 No master IDU
GMV5E DC INVERTER VRF UNITS SERVICE MANUAL
Possible reasons
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.Some indoor units in the system
are not power-connected.
2.Communication wires of some
indoor units in the system are
disconnected or have loose
contact.
3.Controllers of some indoor units
in the system are abnormal.
1.Project numbers conflict with
each other.
1.Communication cables between
ODUs are loose.
2.Communication cables between
ODUs are broken.
3.Communication cables between
ODUs are poorly connected.
4.The control board is faulty.
The SA8 dial switch of the ODU is
not switched to 00.
The SA8 dial switch of the ODU is
faulty.
SA8 dial switches of multiple
ODUs are switched to 00.
Dial switches of multiple ODUs
are faulty.
The master IDU is powered off.
The communication of the master
127
Solution
compressor's drive board. If the fault is solved, the
compressor's drive board is faulty.
1)Check if the cable connecting the fan's drive
board and the compressor's drive board is loose. If
yes, reconnect it;
2)Check if the cable connecting the fan's drive
board and compressor's drive board is broken. If
yes, replace the cable;
3)Check the contact of the communication cable
connecting the fan's drive board and compressor's
drive board;
4)Replace the control board. If the fault is solved,
the control board is faulty. Replace the fan's drive
board. If the fault is solved, the fan's drive board is
faulty.
1. Check the number of online indoor units through
outdoor unit and compare it with the number of
indoor units that are actually installed. Confirm the
number of missing indoor units.
2. Check whether all the indoor units are
power-connected. If some are not, connect them
to power. If power connection is fine, check further
whether there is any indoor unit that fails to display
on wired controller or receiver board. If such
indoor unit exists, it means its main board is
abnormal and needs to be replaced. If everything
said above is confirmed OK, continue to check
according to step 3.
3. The missing indoor units will display error "C0"
on wired controller or receiver board. Check the
communication wire of the missing indoor unit
whether it is disconnected or has loose contact. If
yes, connect the communication wire tightly. If
communication wire is OK, check whether it is
connected reversely. Power on the indoor unit
again and see if error "C0" occurs. If "C0" is
displayed, it means main board is abnormal and
needs to be replaced.
1.Change conflicting project numbers and ensure
that no IDU's project number is repeated.
1.If the communication cable is loose, reconnect it;
2.If the communication cable is broken, replace it;
3.Check contact of the communication cable;
4.Replace the control board.
1.Switch the SA8 dial switch of an ODU to 00;
2.Replace the control board or switch an ODU's
SA8 dial switch to 00.
1.Leave one SA8 dial switch unchanged, while
switch all the other dial switches to 11;
2.Replace the control board.
Check if the master IDU is powered on. If yes,
replace the main board;