Boilers: How to buy the best boiler Choosing a new boiler

There are numerous boiler brands out there, so a good place to start is Which?'s independent review of boilers to find out which new boilers and boiler brands we recommend as Best Buys. Cross reference these with our review of combi gas boiler brands - which scores boiler manufacturers, including Worcester Bosch, British Gas, Vaillant and Baxi, according to how their own customers rate them.

Boiler video buying guide

Buying a new boiler is likely to be one of the most expensive household purchases you'll make - so it's important to choose the best new boiler for your home, at the right price. Watch our video, below, to get top tips on buying the best boiler for you.


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New boiler checklist

First of all, you need to decide which type of new boiler to go for. Here are some key considerations you should bear in mind:

Fuel type

The majority of UK households have a gas heating system equipped with a gas boiler, but for the estimated 4.3m households not connected to the UK's gas network, there are alternatives. Other options include fitting an oil boiler, liquid petroleum gas or LPG boiler, or a wood burning stove fitted with a back boiler - see our home heating systems guide or heating oil guide for more information. 

Boiler type

Decide if you want to replace your boiler with a combination (or combi boiler), which provides heat for your radiators and domestic hot water on demand, or a heat-only boiler, which is connected to a hot water storage system - our combi boiler page will help you decide which type of boiler is best for you. Alternatively, ask a professional installer for their opinion.

Boiler efficiency 

If you have gas central heating, your boiler will account for around 60% of your home's CO2 emissions, according to the Energy Saving Trust. This makes your choice of boiler a key priority if you're looking to cut your energy bills and carbon footprint.

Boiler efficiency is a key part of our independent boiler reviews, you can filter our boiler reviews by efficiency rating using our boiler comparison tool.

Heating controls

Heating controls let you take charge of when, where and at which temperature your heating is operating. It’s a good way of managing your heating costs, as you can ensure that your heating is only on in the rooms and at the times you want it to be. When you come to replace your boiler, it may be a good time to install a heating control system, so a good place to start with this task is by checking out our guide to the best heating controls. 

Gas Safe Register logo

The Gas Safe Register replaced the Corgi scheme in 2009

Boiler installation 

Don't attempt to install a replacement boiler yourself - leave it to the professionals. Find a competent heating engineer on the Gas Safe Register - the gas registration scheme previously run by Corgi - to do the work for you. To be sure of a tradesperson's credentials, ask to see their Gas Safe Register ID card or run a check on the Gas Safe Register website.

Pete Tynan from Which? Local recommends shopping around and getting quotes from several different boiler installers. He says: 'Ask friends and family or look on Which? Local for recommendations for reliable traders. Always get at least three quotes for boiler installation and make sure they include all costs including any call-out fees. Don't be taken in by any headline discount figures - look at the total price of the boiler and labour charges.'

Which? Local only features heating engineers that have been recommended by other Which? members.

You may find that some installation companies, including services offered through British Gas and other energy companies, will suggest a replacement boiler for you rather than allowing you to choose your preferred model - if you already have a specific boiler model in mind, make this clear to the installer from the outset. 

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