Troubleshooting by Error Code
SiUS371901E
339
Service Diagnosis
3.61 Refrigerant Shortage
Error Code
U0
Applicable
Models
All outdoor unit models
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 and refrigerant clogging (wrong piping)
Defective thermistor
Defective low pressure sensor
Defective outdoor unit main PCB
Troubleshooting
Notes:
∗
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.
)
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.
CHECK 12
CHECK 2
CHECK 12
Summary of Contents for REYQ72-456XATJU
Page 415: ...SiUS371901E Wiring Diagrams Appendix 402 REYQ144 168XATJU 2D119206A ...
Page 416: ...Wiring Diagrams SiUS371901E 403 Appendix REYQ72 96 120XAYDU 2D119207B ...
Page 417: ...SiUS371901E Wiring Diagrams Appendix 404 REYQ144 168XAYDU 2D119208B ...
Page 418: ...Wiring Diagrams SiUS371901E 405 Appendix REYQ72 96 120 144 168XAYCU 2D119209A ...
Page 421: ...SiUS371901E Wiring Diagrams Appendix 408 FXZQ05 07 09 12 15 18TAVJU 3D110443A ...
Page 423: ...SiUS371901E Wiring Diagrams Appendix 410 FXEQ07 09 12 15 18 24PVJU 3D098557A ...
Page 426: ...Wiring Diagrams SiUS371901E 413 Appendix FXMQ07 09 12 15 18 24 30 36 48 54PBVJU 3D093209B ...
Page 428: ...Wiring Diagrams SiUS371901E 415 Appendix FXHQ12 24 36MVJU 3D048116C ...
Page 429: ...SiUS371901E Wiring Diagrams Appendix 416 FXAQ07 09 12 18 24PVJU C 3D075354D ...
Page 435: ...SiUS371901E Wiring Diagrams Appendix 422 VAM1200GVJU 3D073270D ...
Page 437: ...SiUS371901E Wiring Diagrams Appendix 424 1 4 2 Multi Branch Selector Unit BS4Q54TVJ 3D089123B ...
Page 438: ...Wiring Diagrams SiUS371901E 425 Appendix BS6 8Q54TVJ 2D089122B ...
Page 439: ...SiUS371901E Wiring Diagrams Appendix 426 BS10 12Q54TVJ 2D089121B ...
Page 440: ...Revision History Month Year Version Revised contents 04 2019 SiUS371901E First edition ...