Two boiler tricks to slash hundreds off your energy bill

As temperatures drop, you may have tried a few tricks to help keep energy bills low, but could these two boiler tricks slash hundreds off your costs?

A hand adjusting a boiler
(Image credit: © Getty Images/iStockphoto)

As the cold snaps kicks in, energy bills are at the forefront of our minds again as we try to keep energy bills low.

Currently, household bills are somewhat protected with the government’s Energy Price Guarantee (EPG), under which the typical average household pays around £2,500 - but this is expected to rise to £3,000 in April. The increase coincides with the end of the government’s £400 energy grant, so households will be feeling added pressure from higher bills on top of rising inflation.

Given the uncertainty around energy prices in 2023, cutting costs now makes sense.

Subscribe to MoneyWeek

Subscribe to MoneyWeek today and get your first six magazine issues absolutely FREE

Get 6 issues free

Sign up to Money Morning

Don't miss the latest investment and personal finances news, market analysis, plus money-saving tips with our free twice-daily newsletter

Don't miss the latest investment and personal finances news, market analysis, plus money-saving tips with our free twice-daily newsletter

Sign up

And to help you, experts say these two simple boiler changes could save you up to £25 a month on your energy bill. Here’s what you need to know.

1. Turn off your boiler’s preheat function

When the preheat function of your boiler is on, hot water is ready to go at all times – even when you’re not using it.

By turning this function off you’ll have to wait a couple of minutes for the water to heat up, but it will shave anywhere between 5% to 10% off your energy bill.

2. Turn down your flow temperature

Combi boilers in the UK are typically set to around 80C, but this isn’t necessarily the most efficient temperature for a boiler to operate at, according to boiler experts.

Lowering your boiler’s flow temperature will regulate the water temperature when it goes from your boiler to your radiator. A lot of heat escapes into the air during this process, so experts recommend you keep your flow temperature low, as this means less heat is lost as the boiler recycles the majority of the heat back into the water to heat it up.

However this option is only available to those with a condensing combi boiler that is not connected to a hot water cylinder, where your hot water is stored. Experts say this tip could save people anywhere between 6% and 8% off their gas bills, and some could see their bills reduced by nearly £100.

To safely turn your boiler’s flow temperature down, have a look at your boiler manual. If you’ve lost it you can type your boiler model into a search engine to get a PDF copy. The lower the temperature, the more efficient your boiler will be.

It’s worth keeping in mind that turning your flow temperature down will mean your house will take a little longer to heat up, but you will be making savings on your energy bills.

A number of energy suppliers are recommending this move for households, including Octopus Energy. Octopus Energy said this is a little-known, but very effective tip for saving gas whilst staying warm. Its customers have reported saving over £100 on their bills.

There are further savings to be made if you have an Economy 7 meter.

Troubleshooting the most common boiler problems

If you’ve decided to turn your boiler on but find it’s not working, don’t panic. “Some problems require professional assistance,” says Ben Gallizzi, boiler expert at Uswitch.

“Others can be fixed by consulting your manufacturer’s manual. Here are some tips from our guide on how to troubleshoot common boiler problems.”

  • Check your manual – this is the first step to resolving an issue. Check the error code displayed on your boiler to identify the issue you need to be targeting.
  • Check your pipes – frozen outdoor pipes can prevent water from reaching the boiler. If your condensate pipe is frozen, heat the area with warm (not boiling) water, a hairdryer, or an electric blanket.
  • Check your thermostat – Make sure your thermostat isn’t disconnected from the boiler, and nudge it up a few degrees to kickstart it. Check any switches to make sure they haven’t been knocked out of place. You could also reset the thermostat if the problem persists.
  • Check your boiler pressure – Your boiler won’t run efficiently if the pressure is too high or too low. Check your pressure gauge, and if there’s an issue follow your boiler instruction manual to repressurise the system.
Nicole García Mérida

Nic studied for a BA in journalism at Cardiff University, and has an MA in magazine journalism from City University. She joined MoneyWeek in 2019.