Weather compensation: adjusting flow temperature to the outdoor climate

How we read weather compensation control on site

On a cold, still night the boiler runs hotter water through the radiators; on a mild afternoon it runs noticeably cooler water, since the house needs far less heat input to stay comfortable. This keeps the boiler operating in its most efficient condensing range for longer than a fixed high flow temperature ever would, and tends to reduce the on-off cycling that wears components out faster.

Weather compensation control: engineer's shortlist

• An outdoor sensor feeds live temperature data to the boiler's controller
• Flow temperature is adjusted automatically rather than set by a dial
• It works best alongside correctly sized radiators for the property
• Reduced cycling can extend the working life of pumps and valves
• Compatible boilers need an OpenTherm or manufacturer-specific link

Questions we get asked

Does weather compensation make rooms colder in mild weather?

No — it delivers exactly the flow temperature needed for the outdoor conditions, so rooms stay at the target temperature with less energy input.

Can any boiler use weather compensation?

It needs a compatible control interface, so it is worth checking against your specific boiler model before fitting the sensor.

Where we deal with this

• Bath (BA1) · 8 mi
• Twerton (BA2) · 7 mi
• Glastonbury (BA6) · 13 mi