Other Control; Outdoor Unit Rotation - Daikin RXYQ5-48MAY1 Service Manual

Si39-407
5.

Other Control

5.1

Outdoor Unit Rotation

In the case of multi-outdoor-unit system, this outdoor unit rotation is used to prevent the
compressor from burning out 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.
Outdoor unit rotation makes it possible to change the operating priority of outdoor units.
Thus, the system becomes free of compressors that stop over an extended period of time at the
time of partial loading, preventing unbalanced oil level.
[Timing of outdoor unit rotation]
or
Example) The following diagram shows outdoor unit rotation in combination of 3 outdoor units.
Starting
control
Normal operation
Master Slave 1 Slave 2
Outdoor unit
Priority
rotation
1
* "Master unit", "slave unit 1" and "slave unit 2" in this section are the names for installation.
Function
• After oil return operation
• After defrosting operation
• At the beginning of the starting control
• When any of compressors stops for a period of 20 minutes or more (in heating
operation)
Oil return operation
or defrosting
operation
Priority Priority
2 3
Normal operation
Master Slave 1 Slave 2
Priority Priority Priority
3 1
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 main PCB for "master unit", "slave unit 1" and "slave
unit 2" do not change. (Refer to the page 90.)
Normal operation
Outdoor unit
Priority
rotation
Any of compressors
stops for a period of 20
minutes or more.
Outdoor unit
rotation
2
Master Slave 1 Slave 2
Priority Priority
3 1 2
Normal operation
Master Slave 1 Slave 2
Priority Priority
2 3

Other Control

Priority
1
99