Gree GMV5E Series Service Manual page 219

GREE
Troubleshooting:
2.2.4.102 "L7" No master IDU
Error display: IDU wired controller and IDU receive light board will display
Error judgment condition and method:
No master IDU error will happen when there is no master IDU in the system
Possible reason：
■Master IDU is offline
■The mainboard of master IDU is replaced
■The mainboard of master IDU has error
GMV5E DC INVERTER VRF UNITS SERVICE MANUAL
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