Home improvements. British Gas Powerflush

A British Gas Powerflush will improve your central heating system, help you use less energy and keep you warm at home. It comes with a lifetime guarantee. 1

Learn more about Powerflush

Everything you need to know about getting a Powerflush

Watch our short video to learn more about our British Gas Powerflush, how it works and why getting one might help improve the performance of your central heating system.

Why you may need a Powerflush

A Powerflush helps deal with heating problems that you can't always see.

Reduced efficiency

Sludge, rust and limescale causes leaks and blocked pipes. Dirty water in your pipes causes heating problems and reduces efficiency.

Cold spots on your radiators

Sludge build-up causes cold spots in your radiators. This means they have to work harder to heat a room and you waste more energy.

Boiler breakdowns

A clogged boiler and pump causes breakdowns. 87% of boiler breakdowns are due to dirty water in your heating system.

Powerflush savings and efficiency

A Powerflush helps prolong the life of your system, lower your bills and reduce the risk of breakdowns.

  • Helps your home heat up faster and wastes less energy
  • Reduces system wear and tear and helps to protect your boiler
  • Lifetime guarantee for all Powerflush customers, provided you have an existing and ongoing HomeCare contract 1

Already have a quote? Accept it online.

Book a free quote

How does a Powerflush work?

Before a Powerflush

The sludge in your radiators creates cold spots so the heat can't flow around them effectively.

During a Powerflush

We'll use a machine and three-step chemical process to thoroughly clean out your boiler, pipes and radiators, and replace dirty sludge with clean water.

After a Powerflush

After the Powerflush has removed sludge from your pipes, radiators and boiler, your system should work much better.

How to book a Powerflush

  • Book a free appointment and one of our engineers will pop over and check your central heating system, then provide a fixed-price quote
  • If you decide to go ahead with a Powerflush, we'll help you book an appointment (it can take around eight hours to complete a Powerflush)
  • We offer a lifetime guarantee for all Powerflush customers, provided they have an existing and ongoing HomeCare contract (read our T&Cs at the bottom of the page for more details)

Already have a quote? Accept it online.

Book a free quote

Need to know more?

How much does a Powerflush cost and what's included?

The price will depend on the size and number of radiators in your home. Contact British Gas for a no obligation quote. We offer a number of easy ways to pay for a Powerflush, including instalments.

What’s included in a Powerflush:

  • Lifetime guarantee – Your British Gas Powerflush is guaranteed for life as long as you remain on an existing and ongoing HomeCare contract, this means that we’ll re-flush your system for free as many times as you need it in the future
  • Each radiator is isolated and flushed individually
  • A full system drain down, de-sludge with a chemical inhibitor added afterwards to prevent future build-up
  • A British Gas engineer completing fixed-price work
  • Read our terms and conditions (PDF, 50.9KB) for more details

How do I check if I need a Powerflush?

Check for cold spots on your radiators by feeling the bottom of them. If they're cooler at the bottom than at the top, you may have a blocked radiator with sludge inside it. A Powerflush will remove the sludge and make your radiators hotter and more efficient. If your heating or hot water is slow to heat up or it's not feeling as hot as usual, your system may be blocked. If you have an old boiler, or one that hasn’t been serviced for a number of years, it may be inefficient or blocked. A qualified gas engineer will confirm this for you. Contact British Gas for an Annual Boiler Service. If you have old pipework or radiators, they may be rusting and causing a build-up of sludge in your heating system. If you have a new boiler, it is important that all sludge is removed from the system, or this could clog up your new boiler, making it less efficient and leading to future breakdowns. Your engineer will check your boiler efficiency during your Annual Boiler Service.

How do I book a Powerflush?

Contact British Gas for a quote, we'll send an engineer over to take a look at your system and give you a free quote. We’ll then contact you to arrange an appointment to carry out the work. If you have already accepted a quote and want to proceed with your Powerflush please contact us to carry out your Powerflush.

How long does a Powerflush take?

Most of our Powerflushes take a full-day appointment that lasts around eight hours. Our engineers will tell you when they are working out your quote. It will depend on the size of your home, how many radiators you have and how blocked or dirty your current heating system is.

How does a Powerflush help?

It improves the circulation of water within your system and makes it more efficient. Your radiators will heat more quickly. It'll reduce the risk of breakdowns, cold radiators and noisy boilers. It'll help prolong the life of your boiler, radiators and systems.

How is a Powerflush done and how does it work?

We'll use a machine and three step chemical process to thoroughly clean out your boiler, pipes and radiators, and replace dirty sludge with clean water using a cleansing agent. We'll need to drain the heating system down and flush every radiator individually. We can then get rid of the waste down a suitable outside drain.

Is my heating suitable for a Powerflush?

We’ll arrange for an engineer to check your heating system is suitable for a Powerflush. The following systems can't be Powerflushed:

  • Electrical heating systems
  • Twin-entry radiator valves
  • Pipes of less than 15mm in diameter

I already have Homecare, is my Powerflush included as a part of that?

Powerflush is not included in any of our HomeCare packages. However, if you buy a British Gas Powerflush, it comes with a Lifetime Guarantee, as long as you have an existing and ongoing Homecare 2, 3 or 4 contract that covers your central heating system. This means we’ll re-flush your system for free as many times as you need it in the future.

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Additional information

  1. A lifetime guarantee is offered to all customers who have purchased a Powerflush, provided they have an existing and ongoing HomeCare contract that covers your central heating system.