Which? research has revealed the best gas and oil boiler brands. There are only three gas boiler brands and two oil boiler brands that are reliable enough to get our Best Buy recommendation.
To determine the best and worst brands, we surveyed more than 12,000 boiler owners and 166 Which? Trusted Trader heating engineers.
These surveys give the UK’s boiler manufacturers nowhere to hide. Our quest to discover the best finds out how often their boilers break down in real people’s homes, and gets the views of trusted heating engineers who work on these boilers every day.
Our research shows that it isn’t necessarily the biggest boiler brands that are the best. Keep reading to find out more – including what trusted heating engineers had to say about the best and worst brands.
To find out how each manufacturer performs, head to our best boiler brands.
Best new boilers
To find out how reliable each boiler manufacturer is, we ask owners that have purchased their boiler new in the past seven years to tell us whether their boiler has broken down and, if so, how often.
After seven years, the best boiler brands are half as likely to have developed any kind of fault, compared with the worst.
This means that our Best Buys will last for longer before they need costly repairs, and will need fewer of them.
Go to our Best Buy boilers.
What did heating engineers say about the least reliable brand?
Heating engineers couldn’t be more negative about our least reliable boiler brand. In our survey, they said it has the worst build quality, is the one they’re least likely to recommend and is the hardest to fix of all the brands in our survey.
Here’s what Which? Trusted traders said about the least reliable brand:
‘Its boilers are unreliable and cheap, with expensive parts; they’re very poorly designed and manufactured.’
‘It’s particularly difficult to identify faults on these boilers and diagnose them. The availability of parts isn’t as good as some manufacturers on the market.’
Here’s what Which? Trusted traders had to say about our Best Buy boiler brands:
‘A quality product, great price… they’re the best boiler you could ever fit for your favourite customers.’
‘By far the best on the market – easy to install, service and change parts on. If fitted right and on a clean system, they’re the most reliable.’
Find a local, trustworthy heating engineer with Which? Trusted Traders.
Why you can trust our boiler reviews
With the cost of any boiler repair at almost £200, not to mention the inconvenience of days without hot water and heating, it’s well worth finding out which are the most reliable brands.
In our boiler reviews, as well as each manufacturer’s reliability record, we’ll tell you how owners of the brand rate them for customer score.
We also reveal how expert heating engineers rate each manufacturer on six factors, including build quality, the availability of parts and spares, how easy the boilers are to repair and service, and more.
So our research is a treasure trove of information on every major gas and oil boiler manufacturer in the UK. We can tell you which brands break down the least, and which keep their customers happy long after the installer has left.
We turn all of this rigorous data into easy-to-understand star ratings and an overall Which? test score, so you can see at a glance the brands we recommend and the ones you should avoid. We also pair this with detailed specification information from every boiler within each brand’s range.
See our boiler reviews.