Troubleshooting by Error Code
SiUS341802EC
339
Part 6 Service Diagnosis
3.66 Transmission Error between Indoor Units and Outdoor
Units, Open Phase in Power Supply Wiring
Applicable
Models
All indoor unit models
All outdoor unit models
Error Code
U4
Method of Error
Detection
Microcomputer checks if transmission between indoor and outdoor units is normal.
Error Decision
Conditions
Transmission is not carried out normally for a certain amount of time.
Supposed
Causes
Open phase in power supply wiring
Short circuit in indoor-outdoor or outdoor-outdoor transmission wiring (F1/F2), or wrong wiring
Outdoor unit power supply is OFF
System address does not match
Defective indoor unit control PCB
Defective outdoor unit main PCB
Multi-tenant function is ON.
Summary of Contents for VRV Aurora RXLQ-TATJU Series
Page 407: ...SiUS341802EC Wiring Diagrams Part 7 Appendix 400 RXLQ96 120TATJU RXLQ96 120TATJA 2D112581C...
Page 409: ...SiUS341802EC Wiring Diagrams Part 7 Appendix 402 RXLQ72TAYDU RXLQ72TAYDA 2D112582D...
Page 411: ...SiUS341802EC Wiring Diagrams Part 7 Appendix 404 RXLQ96 120TAYDU RXLQ96 120TAYDA 2D112583D...
Page 417: ...SiUS341802EC Wiring Diagrams Part 7 Appendix 410 FXFQ07 09 12 15 18 24 30 36 48TVJU 3D086460B...
Page 420: ...Wiring Diagrams SiUS341802EC 413 Part 7 Appendix FXZQ05 07 09 12 15 18TAVJU 3D110443A...
Page 425: ...SiUS341802EC Wiring Diagrams Part 7 Appendix 418 FXEQ07 09 12 15 18 24PVJU 3D098557A...
Page 426: ...Wiring Diagrams SiUS341802EC 419 Part 7 Appendix FXDQ07 09 12 18 24MVJU C 3D050501C...
Page 433: ...SiUS341802EC Wiring Diagrams Part 7 Appendix 426 FXHQ12 24 36MVJU 3D048116C...
Page 434: ...Wiring Diagrams SiUS341802EC 427 Part 7 Appendix FXAQ07 09 12 18 24PVJU 3D075354F...
Page 441: ...SiUS341802EC Wiring Diagrams Part 7 Appendix 434 VAM1200GVJU 3D073270D...