SiUS342004EB
Troubleshooting by Error Code
Part 6 Service Diagnosis
326
3.60 Power Supply Insufficient or Instantaneous Abnormality
Applicable
Models
All outdoor unit models
Error Code
U2
Method of Error
Detection
Detect the voltage of capacitor of the main circuit in the inverter PCB.
Error Decision
Conditions
When the voltage in the DC circuit (between diode module and power module) falls below 560
VDC.
Supposed
Causes
Abnormal power supply voltage
Instantaneous power failure
Open phase
Defective inverter PCB
Defective outdoor unit main PCB
Defective compressor
Defective main circuit wiring
Defective fan motor
Defective connection of signal cable
Troubleshooting
There are
some defects in the
power s
u
pply conditions
aforementioned.
The ins
u
lation
resistance of the
compressor is less than
100 k
.
NO
YES
YES
Fix the defects.
Replace the compressor
(M1C).
Check for power s
u
pply
conditions.
(1) Power s
u
pply
v
oltage falls
within ±10
%
of the rated
v
oltage?
(2) Any open phase in the
power s
u
pply wiring or any
wrong wiring?
(3) Im
b
alance in the power
s
u
pply
v
oltage is
maintained within 12 V?
A
NO
Caution
Be s
u
re to t
u
rn off the power switch
b
efore connecting or disconnecting
connectors, or parts may
b
e damaged.
Go to the next page.
Summary of Contents for VRV RXYQ72-384XAYCA
Page 1: ...Service Manual RXYQ72 384XAYCA RXYQ72 384XBYCA Heat Pump 60 Hz SiUS342004EB...
Page 395: ...SiUS342004EB Wiring Diagrams Part 7 Appendix 388 FXFQ07 09 12 15 18 24 30 36 48TVJU 3D086460B...
Page 397: ...SiUS342004EB Wiring Diagrams Part 7 Appendix 390 FXZQ05 07 09 12 15 18TAVJU 3D110443A...
Page 401: ...SiUS342004EB Wiring Diagrams Part 7 Appendix 394 FXEQ07 09 12 15 18 24PVJU 3D098557A...
Page 402: ...Wiring Diagrams SiUS342004EB 395 Part 7 Appendix FXDQ07 09 12 18 24MVJU C 3D050501C...
Page 409: ...SiUS342004EB Wiring Diagrams Part 7 Appendix 402 FXHQ12 24 36MVJU 3D048116C...
Page 410: ...Wiring Diagrams SiUS342004EB 403 Part 7 Appendix FXAQ07 09 12 18 24PVJU 3D075354F...
Page 418: ...Wiring Diagrams SiUS342004EB 411 Part 7 Appendix VAM1200GVJU 3D073270D...