Millions of British households could be unknowingly burning through cash every time they turn up the heating, according to energy efficiency experts. A remarkably simple adjustment to your combi boiler's settings could potentially save the average home over £100 per year on gas bills.
The Hidden Setting Costing You Money
Most modern combi boilers come with a default flow temperature setting that's often higher than necessary. This is the temperature at which water leaves your boiler to heat your radiators and provide hot water. While manufacturers typically set this between 75°C and 80°C, experts from Nesta argue this is inefficient for most homes.
"Many people are essentially overheating their homes without realising it," explains one energy consultant. "Your boiler works much more efficiently at lower temperatures, and you'll barely notice the difference in comfort."
How to Make the Change in Minutes
Adjusting your flow temperature is surprisingly straightforward and requires no technical expertise:
- Locate the central heating flow temperature dial on your boiler (usually marked with radiator icons)
- Gradually reduce the temperature to 60°C for heating
- For hot water, aim for 50°C to balance efficiency and safety
- Allow 24 hours to assess comfort levels
- Adjust slightly if needed, but avoid returning to original high settings
Why This Simple Change Works
Combi boilers operate most efficiently in condensing mode, which occurs when return water temperature is below 55°C. By lowering flow temperature, your boiler condenses more effectively, capturing additional heat that would otherwise escape through the flue.
"This isn't about being cold - it's about being smart with your heating," says a Nesta spokesperson. "Most households will maintain comfortable temperatures while using significantly less gas."
The Potential National Impact
If just 10 million households made this adjustment, the collective savings could reach approximately £1 billion annually. With energy prices remaining historically high, this simple hack represents one of the easiest ways to reduce household expenses without compromising comfort.
The adjustment is particularly effective during milder weather when full heating capacity is unnecessary. Many users report their homes feel more consistently comfortable with fewer temperature fluctuations.
Important note: While this advice applies to most modern combi boilers, households with older heating systems or specific health requirements should consult with a qualified heating engineer before making changes.
