Heating Curve


The desired target temperature can be set with the analogue input T (= temperature). The desired temperature can either be set with a virtual input connector or a timer switch.
An actual temperature reading from a temperature sensor in the respective room should be connected to the analogue input AI.

Activating the disable input Dis locks the input T, which means that the last value for T to be entered is used for temperature control. Any further changes to the set temperature will be ignored. This could be used, for example, as a child lock.


The parameter S is used to adjust the gradient of the heating system, this parameter must be adjusted for each heating system.

Setting values for slope S:

Under floor heating 0.25-0.5
Panel radiators 1.26-1.33
Heaters conforming to DIN 4703 1.3
Convection heater 1.25-1.45

The parameter N adjusts the heating curve’s offset. This enables you to increase the desired flow temperature by a value N.

The parameters Min and Max set the maximum and minimum flow temperatures.


Heating Curve Diagram

a: Supply Temperature in °C; b: Outdoor Temperature in °C; c: Gradient; d: Offset
Photo Source: http://de.wikipedia.org/wiki/Heizkurve
This behaviour is based on a target value (parameter d) of 20°C.


The analogue output AQ gives the actual flow temperature required. For temperature compensation enable the Dis input and then AQ will be based on the input temperature at AI and the parameters. The output Q is a digital error output which is activated if:

  • The outside temperature exceeds the room temperature (in which case the minimum flow temperature is output).
  • The temperature of the room exceeds the outside temperature by more than 80°C. i.e. if the room temperature is 20°C the outside temperature must not fall below -60°C otherwise the error output will be issued and the maximum flow temperature will be the output.