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Control device
Cooling
Heating
Heat recovery
Defrost
Purpose
Contents
Purpose
Contents
Contents
High and low
pressure shut-off
valve (SVG)
Shut-off of high
and low pressure
in the cycle during
stoppage
Compressor
operating: ON
Compressor
stopped: OFF
Shut-off of high
and low pressure
in the cycle during
stoppage
Compressor
operating: ON
Compressor
stopped: OFF
Open
Pd: Discharge pressure.
Ps: Suction pressure.
SH: Superheat.
SC: Supercooling.
TdSH: Superheat of discharge gas temperature.
5.1.2 Compressor operation control
¿
Compressor rotation control
The compressor rotation control is carried out to match its operation time in each of the outdoor units.
This control is carried out during the Thermo-OFF of the outdoor unit.
In case of switch-OFF or Thermo-OFF after 120 minutes of operation, the inverter compressor with the shortest operation
time will be preferably turned on.
N O T E
In order to carry out this function, at least two outdoor units are required.
The operating sequence of the compressor rotation is described below.
RAS-20FSXN
Outdoor unit 1
Outdoor unit 2
-I-
Last time
1
2
Currently
2
1
Next time
1
2
-I-
Inverter compressor
RAS-(22-26)FSXN
Outdoor unit 1
Outdoor unit 2
-I-
-C-
-I-
Last time
1
3
2
Currently
2
3
1
Next time
1
3
2
-I-
Inverter compressor
-C-
Constant compressor
5 Control system
89
SMGB0065 rev. 1 - 12/2010
5