Main Control Logic; Compressor Capacity Control - Siemens POLYCOOL RWR470.10 Basic Documentation

Siemens Building Technologies
HVAC Products
9

Main Control Logic

Compressor Capacity Control

For the compressor with stages, it will be started with full capacity when the system on.
+
Band1
Cooling
Setpoint
Band1
In cooling mode:
• When the actual supply/return temperature is higher than the cooling setpoint (ST01)
+ temperature band (ST03), the compressor capacity will be gradually increased by
stages every a preset time (ST17).
• When the actual supply/return temperature is lower than the cooling setpoint (ST01) -
temperature band (ST03), the compressor capacity will be gradually decreased by
stages every a preset time (ST17).
+
Band2
Heating
Setpoint
Band2
In heating mode:
• When the actual supply/return temperature is lower than the heating setpoint (ST02) -
temperature band (ST04), the compressor capacity will be gradually increased by
stages every a preset time (ST17).
• When the actual supply/return temperature is higher than the heating setpoint (ST02)
+ temperature band (ST04), the compressor capacity will be gradually decreased by
stages every a preset time (ST17).
SIEMENS Controller
+
Time
+
Time
HEAT PUMP controller
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27.11.2006