How to decide between boiler cover, boiler repair or boiler replacement

Get to know your options when it comes to keeping your boiler running smoothly so you stay warm and cosy.

What’s best for my boiler?

When your boiler is having issues, it can be tricky to know what to do. Repair it? Buy some boiler cover? Replace it altogether? There’s a lot to think about when all you want is a nice warm home and hot water.

And even if your boiler is behaving itself at the moment, it’s worth considering your options to ensure that you have cover if you need it or know what to do in case of difficulties.

Replacing a perfectly decent boiler before you need to might be expensive – but it’s worth doing the sums because newer models are more energy-efficient than older ones, so a replacement could actually work out cheaper in the long run. Similarly, although you could look at boiler cover as an extra outlay, it could work out the most cost-effective way to keep your home running smoothly, compared to paying for one-off repairs as and when you need them.

We run through the options in different scenarios – and do the workings out so you don’t have to!

Boiler cover

It used to be that the only choice you had was between shelling out for boiler replacement cover, or taking the hit and paying for one-off repairs or replacements as and when you needed them. On the one hand, you might end up paying over the odds for cover that you don’t end up making use of. On the other, you could be faced with a big old bill when you least expect it.

Lots of companies offer boiler insurance, but British Gas HomeCare offers four different levels of cover that you can choose from depending on your needs and budget – and all of them include an annual service visit to keep your boiler in tip-top shape.

What is a boiler service?

An annual service is a bit like an MOT for your boiler. An engineer from British Gas will carry out essential maintenance checks on all the key parts of your boiler, which helps to reduce the risk of breakdowns and other problems in the future.

You can either book a one-off boiler service by a British Gas engineer, or get one included at no extra cost with any level of HomeCare cover. With a HomeCare boiler service, you don’t need to remember to book one the following year. We’ll just get in touch when it’s time for your next annual check.

Our Summer Sale

Summer Sale 25% off HomeCare​

Protect your home against heating, plumbing and electrical breakdowns. Offer ends 9th September. T&Cs apply.1

Get covered​

Summer Sale Get an annual boiler service for only £79

Save big on an annual service (normally £109) – or pay just £69 if you join British Gas Membership for free! Sale ends 9th Sep. T&Cs apply.2

Book yours now

What does a boiler service include?

Your engineer will carry out a range of important checks to make sure your boiler is working properly. These include:

  • Inspecting your boiler and controls to make sure everything’s safe
  • Opening up your boiler to check internal components
  • Checking for corrosion and leaks in the boiler
  • Cleaning the system filter
  • Giving you a boiler safety checklist, plus advice on energy efficiency

Does a boiler service include radiator checks?

No, a standard boiler service doesn’t include radiator checks. However, with British Gas you can always ask your engineer to upgrade to a System Service Plus.

This costs a little bit more, but it gives you the extra peace of mind that comes from having radiators, pipework and the whole central heating system inspected at the same time as your boiler is serviced.

Also, if you take out HomeCare Essential, Classic or Complete, your annual boiler service will include a check of your whole central heating system.

Boiler repairs

If you’re having issues with your boiler or your central heating, it could be something that you can sort out yourself, or get repaired by a Gas Safe engineer. For example:

Water pressure issues

Take a look at our handy guide to water pressure issues to see if you can diagnose and resolve the problem yourself. If not, calling out a Gas Safe engineer is likely to be more economical than boiler replacement.

Radiators heating poorly

With any luck, this is easily solved (for free!) by bleeding your radiators. If not, it could be down to deposits building up in your system, slowing it down. A Gas Safe engineer can arrange a chemical Powerflush to clear the system before any major damage is done. This is more cost effective than boiler replacement, but might not be the answer if the corrosion is extensive.

Minor low-cost issues

The ten most common boiler faults had an average repair cost ranging from £115 (to replace an overheat thermostat or automatic air vent) to £305 (to replace a printed circuit board). However, it’s worth bearing in mind that some repairs can cost over £1000.

So if your boiler has a few years of safe and efficient service left in it, it’s worth fixing them rather than replacing your boiler straight away.

Boiler replacements

To replace or not to replace, that is the question. Even if you’re not experiencing any issues with your boiler, you might still want to consider replacing it if it’s getting on a bit. Today’s boilers are far more energy efficient than those of even just a few years ago, so replacing your boiler with a newer model can help you save money on your bills, as well as helping you reduce the carbon emissions of your home. If you want to find out more about energy efficiency, you can read our dedicated guide.

A new boiler can cost anything from £500 to £3150, according to Which? and we can help you find the right boiler for you. And if you’ve got HomeCare, it might be even lighter on your wallet.

You’ll need to consider replacing your boiler if it experiences:

Heavy corrosion

Impurities and water acidity can eat away at your boiler’s internal electrics and seals if it isn’t serviced regularly. Efficiency will suffer as a result, and it’ll need extensive repairs – so a replacement might make more sense. Have a Gas Safe engineer take a look if you notice signs of rust or corrosion on the outer casing, seams, or water inlet of your boiler.

Water leaks

While a leaky modern boiler is often straightforward to fix, cast-iron boilers are more of a challenge. They will most likely need to be dismantled if the leak is caused by a crack in the iron body, and the extra labour will be expensive so it could be better to replace it. Learn more in our guide to the different types of boilers.

Poor combustion

This poses serious risks, including carbon monoxide leaks, fire and even explosion. Telltale signs are soot on or around your boiler, or the pilot light repeatedly blowing out, get it inspected by a Gas Safe engineer straight away.

They might condemn the boiler, but don’t panic. Scary as it sounds, your engineer will make sure everything’s safe, before advising you on the next step. For safety’s sake, this may well be replacement.

Dangerous flue

Your entire flue, along with your boiler, needs to be inspected annually to make sure it meets safety standards. All modern gas boilers have flues with inspection hatches and so meet current Gas Safe Regulations, but if your boiler is older and has a concealed flue (in a ceiling or wall void) your Gas Safe engineer must mark it as ‘at risk’ because they're unable to check its whole length and so can't confirm it won’t become dangerous. They’ll also recommend that you no longer use your boiler.

You may need to put in inspection hatches, move your boiler or install a new flue – or even all three. When you add up the cost of the work, it could end up costing as much as a full installation. If it does, it's worth considering a boiler upgrade.

Need help?

Remember, your trusted Gas Safe engineer will always be the best person to advise you on your individual circumstances. So if you're unsure about any aspect of your boiler's performance, or safety, you can book a heating consultation  or see our guide to finding your own trusted Gas Engineer.

Additional information

  1. This offer is available to homeowners who do not currently have HomeCare at their specified property and have not held a HomeCare product for that property in the previous 3 months. For new British Gas Services customers, the discount will apply to the first year’s cost only. For existing British Gas Services customers, the discount will apply to the remaining term of your existing services contract for that property. Renewals will be charged in accordance with our standard pricing. We will contact you about any change to the price. A maximum of 9 properties can be covered per customer (whether as homeowner or landlord). Offer cannot be used in conjunction with any other offers that may be available on your chosen HomeCare product. Offer ends 9th September 2025.​

  2. The discount is applied to either the one-off boiler service cost or the first year of an annual boiler service, depending on your selection. If you choose an annual boiler service, it will renew at standard pricing according to your renewal preference. This offer cannot be used in conjunction with any other Boiler Service-related offers. Offer not available to existing HomeCare or boiler service contract customers. Promotion ends 09/09/2025. Boiler service must be completed by 30/09/2025 to qualify.