Why vary the flow temperature?
A building generally needs less heat when it is mild outside and more when outdoor temperature falls. Rather than using the same heating-water temperature in every condition, weather compensation adjusts the target according to a configured heating curve.
Heat pumps
This approach is particularly relevant to heat pumps because avoiding unnecessarily high flow temperatures can support efficient operation. The correct curve still needs to deliver enough heat to maintain the required indoor temperature.
Boilers
Compatible modern boilers can also benefit from more sophisticated temperature control rather than simply operating at a fixed high flow temperature, subject to the boiler and system design.
What is a heating curve?
The curve defines the relationship between outdoor temperature and target heating-water temperature. If the curve is set incorrectly, rooms may be too cool or the system may run hotter than necessary.
Do not change settings blindly
Control adjustments should be made with an understanding of the building and system. If a heat pump is not achieving comfort, the cause could also involve emitters, circulation or system design rather than the weather-compensation setting alone.
Read our heat pump flow temperature guide for more information.