Outdoor Unit Rotation - Daikin REYQ-XA Service Manual

SiUS371901E
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
•
•
•
•
Example) The following diagram shows outdoor unit rotation in combination of 3 outdoor units.
Startup control
Master Slave 1 Slave 2
Outdoor unit
Priority
rotation
A
Master Slave 1 Slave 2
Priority
∗ Master unit, slave unit 1 and slave unit 2 in this section are the names for installation.
Note:
Functions and Control
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).
Oil return control
or defrost control
Normal control
Priority Priority
1 2 3
Normal control
Priority Priority
3 1 2
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
Master Slave 1 Slave 2
Outdoor unit
Priority
rotation
3
One of the outdoor
units is stopped for
20 minutes or more
Normal control
Outdoor unit
rotation
Special Control
Priority Priority
1 2
Master Slave 1 Slave 2
Priority Priority Priority
2 3 1
A
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