Weather Compensation.
01
MEASURE
An outdoor sensor reads the temperature.
02
CALCULATE
The heating curve determines the target flow temperature.
03
ADJUST
The system raises or lowers water temperature.
04
MAINTAIN
Heat output follows the home’s changing needs.
THE SIMPLE VERSION
It watches the weather outside.
Weather compensation automatically adjusts the water temperature circulating through your heating system according to outdoor conditions.
Rather than always sending water around at a fixed high temperature, a correctly configured controller makes small, controlled adjustments to match the heat your home is losing.
The result can be steadier comfort and more efficient operation, particularly with heat pumps.
CHANGING WEATHER
Different days. Different heating needs.
Mild outside.
The heating can use a lower flow temperature and run gently.
Cold outside.
The system raises the flow temperature to replace the additional heat being lost.
Freezing outside.
A higher flow temperature may be needed to maintain the indoor set point.
HEAT PUMPS
This is where weather compensation really matters.
Heat pumps generally work most efficiently when they can supply the required heat at the lowest practical water temperature .
Weather compensation helps them avoid unnecessarily high flow temperatures while maintaining comfort. The correct heating curve depends on the building and its heat emitters.
Illustrative flow temperatures
Mild day → 35°C
Cool day → 40°C
Cold day → 45°C
These are examples, not recommended settings for every property.
THE HEATING CURVE
The clever bit is the curve.
A heating curve describes how the required flow temperature changes as outdoor temperature rises or falls.
Its slope and position need to suit your insulation, room-by-room heat loss, radiator or underfloor-heating output and comfort requirements.
Set it. Fine-tune it. Then let it work.
- Allow time for the system and rooms to settle after changes.
- Avoid repeated large thermostat adjustments.
- If the home stays consistently too warm or cold, review the curve.
- Consult the installer or system designer before making major control changes.
THE DIFFERENCE
Reactive control versus weather compensation.
Room temperature control
The thermostat responds when the indoor temperature deviates from its set point. With simple on/off controls, this can create more noticeable heating cycles.
This is a simplified comparison; many modern systems also modulate their output.
Weather-compensated control
The controller anticipates changing heat demand from the outdoor temperature and adjusts the flow-temperature target.
Room sensors and thermostats may still be used alongside weather compensation to refine comfort and prevent overheating.
WHAT DOES IT FEEL LIKE?
Heating becomes less dramatic.
A correctly designed and commissioned system can deliver more consistent background warmth, with fewer big shifts between cooling down and reheating.
STEADIER WARMTH
APPROPRIATE FLOW TEMPERATURES
FEWER LARGE SWINGS
CONTROLLED HEATING
THE BIGGER PICTURE
Smart controls don’t create heat. They manage it.
Insulation reduces heat loss. Your heating system replaces the heat that escapes. Good controls help supply that heat at an appropriate time and temperature .