Boiler flow temperature at 55°C — saved me £94 in 3 months, here is how to do it

Most boilers are set to 75-80°C flow temperature by default, which is far higher than needed for modern radiators and wastes a huge amount of energy. I dropped mine to 55°C in January and have saved around £94 over 3 months based on my smart meter readings.

How to do it: On most combi boilers there is a dial or button labelled “CH” (central heating) or a flame symbol — not the hot water dial. Turn this down to around 55-60°C. Your radiators will take slightly longer to heat up but the house reaches the same temperature — the boiler just runs more efficiently in “condensing mode” at lower flow temperatures.

Works best with: modern combi boilers, well-insulated homes, and if you have a heat pump it already runs at these temperatures.

Does NOT work well if: you have old single-panel radiators that are already undersized, or if you have a hot water cylinder (that needs to stay at 60°C for legionella safety).

Has anyone else tried this? What savings did you see?