SiUS371901EB
Troubleshooting by Error Code
Part 6 Service Diagnosis
380
Note(s)
Reference
Reference
3.61 Refrigerant Shortage
Applicable
Models
All outdoor unit models
Error Code
U0
Method of Error
Detection
Detect refrigerant shortage according to a low pressure level or a difference in heat exchanging
temperature from the suction pipe.
Error Decision
Conditions
Low pressure becomes 0.1 MPa (14.5 psi) or less.
∗
Error is not determined. The unit continues the operation.
Supposed
Causes
Refrigerant shortage or refrigerant clogging (wrong piping)
Defective thermistor
Defective low pressure sensor
Defective outdoor unit main PCB
Troubleshooting
CHECK 2
Refer to page 417.
CHECK 12
Refer to page 432.
Is the low
pressure 0.1 MPa
(14.5 psi) or less?
(
∗
1)
Is the
characteristics of
low pressure sensor
normal? (
∗
2)
Replace the low pressure
sensor (S1NPL).
Replace the outdoor unit
main PCB (A1P).
NO
NO
YES
YES
Eliminate factors that cause
decreasing low pressure.
CHECK 2
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
(1) Mount a pressure gauge at the service port on the low
pressure side.
(2) Reset the operation using the remote controller then
restart.
∗
1. Check the low pressure value by using pressure gauge in operation.
∗
2. Compare the actual measurement value by pressure sensor with the value by the
pressure gauge.
(To gain actual measurement value by pressure sensor, measure the voltage at the
connector [between (2)-(3)] and then convert the value into pressure.
CHECK 12
)
Summary of Contents for REYQ72-432XAYCU
Page 455: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 448 REYQ144 168XATJU REYQ144 168XATJA 2D119206B ...
Page 457: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 450 REYQ144 168XAYDU REYQ144 168XAYDA 2D119208C ...
Page 461: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 454 FXZQ05 07 09 12 15 18TAVJU 3D110443A ...
Page 463: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 456 FXEQ07 09 12 15 18 24PVJU 3D098557A ...
Page 464: ...Wiring Diagrams SiUS371901EB 457 Part 7 Appendix FXDQ07 09 12 18 24MVJU C 3D050501C ...
Page 468: ...Wiring Diagrams SiUS371901EB 461 Part 7 Appendix FXHQ12 24 36MVJU 3D048116C ...
Page 469: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 462 FXAQ07 09 12 18 24PVJU 3D075354F ...
Page 475: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 468 VAM1200GVJU 3D073270D ...
Page 478: ...Wiring Diagrams SiUS371901EB 471 Part 7 Appendix BS6 8Q54TVJ 2D089122B ...
Page 479: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 472 BS10 12Q54TVJ 2D089121B ...
Page 481: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 474 BSF6 8Q54TVJ 2D123905A ...