GREE GMV5E DC INVERTER VRF UNITS SERVICE MANUAL
230
2.2.4.131
“U0” Insufficient compressor preheating time
Error display:
ODU mainboard, IDU wired controller and IDU receive light board will
display
Error judgment condition and method:
If it is detected that the oil temperature preheating time of compressor before startup doesn
’t reach 8
hours, it will report this error.
Possible reason
：——
Troubleshooting:
The complete unit shall be preheated for more than 8 hours before startup.
2.2.4.132
“U2” ODU capacity DIP switch/jumper cap setting error
Error display:
ODU mainboard, IDU wired controller and IDU receive light board will
display
Error judgment condition and method:
ODU mainboard detects that the capacity code doesn
’t comply with the actual unit capacity, or ODU
mainboard detects that the jumper cap value doesn
’t comply with the actual unit
Possible reason
：
■Capacity DIP switch is wrong or jumper cap is wrong (for those models without jumper cap, it won’t
be detected)
■DIP switch or jumper cap is broken
■Detecting circuit is abnormal
Troubleshooting:
2.2.4.133
“U3” Power phase sequence protection
Error display:
ODU mainboard, IDU wired controller and IDU receive light board will
display
Error judgment condition and method:
If phase loss or reverse of three-phase power is detected (e.g. incorrect connection of power supply
