SiUS371901E
Special Control
Functions and Control
128
7.4
Outdoor Unit Rotation
In the case of multi outdoor unit system, this outdoor unit rotation prevents the compressor from
breaking down due to unbalanced oil level between outdoor units.
Details of outdoor unit rotation
In the case of multi outdoor unit system, each outdoor unit is given an operating priority for the
control.
The operating priority of outdoor units is changed by outdoor unit rotation. The outdoor unit rotation
prevents unbalanced oil level between outdoor units by eliminating the long stop of compressors
during partial load.
Timing of outdoor unit rotation
•
At the beginning of the startup control, or;
•
After oil return control, or;
•
After defrost control, or;
•
One of the outdoor units is stopped for 20 minutes or more (only in cooling).
Example) The following diagram shows outdoor unit rotation in combination of 3 outdoor units.
Note:
∗
Master unit, slave unit 1 and slave unit 2 in this section are the names for installation.
They are determined in installation work, and not changed thereafter. (These names are different
from master unit and slave unit for control.)
The outdoor unit connected the control wires (F1 and F2) for the indoor unit should be designated
as master unit.
Consequently, The LED display on the outdoor unit main PCB for master unit, slave unit 1 and
slave unit 2 do not change.
Normal control
Normal control
Normal control
Normal control
Master Slave 1 Slave 2
Master Slave 1 Slave 2
Master Slave 1 Slave 2
Master Slave 1 Slave 2
A
A
Startup control
Outdoor unit
rotation
Outdoor unit
rotation
Outdoor unit
rotation
Priority
1
Priority
1
Priority
2
Priority
2
Priority
3
Priority
3
Priority
1
Priority
2
Priority
3
Priority
3
Priority
1
Priority
2
Oil return control
or defrost control
One of the outdoor
units is stopped for
20 minutes or more
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 ...