Gree GMV5 Series Service Manual page 133

Communication
failure between
C3 main control board
and variable
frequency fan drive
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
Project number
C5
conflict
Note: Solution of C5 fault when multiple cooling systems are controlled in a centralized way
When multiple cooling systems are controlled in a centralized way, the C5 fault, i.e. project
number conflict, may occur on different cooling systems. In such case, set project numbers of
each system and solve the fault as follows:
1) Project number conflict:
When multiple systems are controlled in a centralized way, if two or more IDUs share the same
project number, the engineer number conflict occurs. In that case, IDUs cannot be switched to
varied modes or be turned on or off. The whole device cannot be started before the conflict is
solved. The commissioning software will show the following page:
GMV5 DC INVERTER VRF UNITS SERVICE MANUAL
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. 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.
1. The SA8 dial switch of the ODU
is not switched to 00.
2. The SA8 dial switch of the ODU
is faulty.
1. SA8 dial switches of multiple
ODUs are switched to 00.
2. Dial switches of multiple ODUs
are faulty.
1. The master IDU is powered off.
2. The communication of the master
IDU fails.
3. The main board of the master
IDU is faulty.
4. No master IDU is set in the
system.
1. Multiple IDUs share one project
number.
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. 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.
1. Check if the master IDU is powered on. If yes,
replace the main board;
2. Check the contact of the communication cable of
the master IDU. If no communication failure (C0) is
reported, replace the main board.
3. Replace the IDU's main board and reset the
master IDU.
4. Set the master IDU.
1. Reset the repeated project number (useful when
there is no centralized control of multiple systems).
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