6.3.4.2 HP Mode
In HP mode the fan controls evaporator pressure since the outdoor unit works as an evaporator.
Optimal Pressure Ratio Control
In Optimal COP mode, the fan speed control attempts to maintain a constant pressure ratio
Pc/P0 = constant
across the compressor, see
. This ratio is the theoretically optimal pressure ratio for the compressor.
To run optimal COP mode:
Set THERMO_IN_FAN_MODE = 0
PI
Σ
1
----------
2
.
09
P 2 T
Pc
T 0
set
FanMotor
Evaporator
P 2 T
P 0
T 0
175ZB112.10
Illustration 6.11 HP Mode
Delta T Control
In Delta T mode, the fan speed control attempts to maintain a temperature difference of Delta T to ambient temperature,
see
In HP mode, the fan speed control attempts to maintain evaporator temperature Delta T below ambient temperature.
To run Delta T mode:
Set THERMO_IN_FAN_MODE = 1
The temperature difference Delta T is set through the register THERMO_SETUP_DELTA_TEMP.
PI
Σ
Tamb
- Delta T
FanMotor
Evaporator
P 2 T
P 0
T 0
175ZB113.10
Illustration 6.12 Delta T Control
Embedded Application Contro...
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