5.8 Control parameters
Control of valves
The motorized control valves are controlled by means of 3-point
control signal.
Valve control:
The motorized control valve is opened gradually when the flow
temperature is lower than the desired flow temperature and vice
versa.
The water flow through the control valve is managed by means
of an electric actuator. The combination "actuator" and "control
valve" is also called motorized control valve. The actuator can in
this way gradually increase or decrease the flow in order to change
the supplied energy. Different types of actuators are available.
3-point controlled actuator:
The electric actuator contains a reversible gear-motor. Electric
"open" and "close" signals come from the electronic outputs of the
ECL Comfort controller in order to manage the control valve. The
signals are in the ECL Comfort controller expressed as "Arrow-up"
(open) and "Arrow-down" (close) and displayed at the valve symbol.
When the flow temperature (for example at S3) is lower than the
desired flow temperature, short open-signals come from the ECL
Comfort controller in order to gradually increase the flow. By this,
the flow temperature will align with the desired temperature.
Oppositely, when the flow temperature is higher than the desired
flow temperature, short close-signals come from the ECL Comfort
controller in order to gradually reduce the flow. Again, the flow
temperature aligns with the desired temperature.
Neither open-signals nor close-signals will come as long as the flow
temperature corresponds to the desired temperature.
VI.GU.L2.02
© Danfoss | 2017.09 | 135
Operating Guide ECL Comfort 210/296/310, application A275/A375
