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ESIE08-01
3.3.7
Outdoor Unit Functional Concept
Suction Pipe Superheat Protection Control (Heating Mode)
Outline
1
In case the suction superheat value in heating mode is too high, the oil return to the compressor will
be insufficient. In order to avoid that the compressor oil will be accumulated in the outdoor unit heat
exchanger, the upper limit frequency will be decreased.
2
Flow chart
· Suction SH > 12˚C
· Suction SH > 10˚C
· EV opening degree
OR
Normal operation
OR
= 480 pls
OR
· Suction SH < 6˚C
· & · Suction SH < 10˚C
· EV opening degree
< 450 pls
Lowering upper limit
frequency for 1-step
every 20 seconds
OR
· Suction SH < 6˚C
· & · Upper limit frequency = Maximum frequency
· OR · Suction SH < 8˚C
· & · Suction SH < 10˚C
· EV opening degree < 450 pls
Raising upper limit
frequency for 1-step
every 20 seconds
· Suction SH > 12˚C
· Suction SH > 10˚C
· & · EV opening degree = 450 pls
3
4
5
Part 2 – Functional Description
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