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Condensing, conventional, combi? Cracking the boiler code

Need a new boiler but can't tell your combis from your conventionals? Take a look at our jargon buster and work out which type of boiler would suit your home.

Thinking about getting a new boiler? With a few types to choose from, you're probably wondering what sets each one apart from another. Here we tell you all the important stuff you need to know about the different types of boiler so you can decide which one would be most suitable for your home.

Why a condensing boiler?

No matter what type of boiler you're thinking of having installed, the law says that it must be a condensing one. All condensing boilers are at least 90% energy efficient, are able to harness excess energy to heat your home, are better for the environment and will help to reduce your heating bills.

The conventional route

A great choice for bigger properties, a conventional boiler (otherwise known as a regular or traditional boiler) is able to heat water for several bathrooms. You could cut your energy bills down by combining it with a solar heating system.

However, a conventional boiler may not be compatible with some newer heating systems, and you might have to wait a while for water to get up to the right temperature. Also, bear in mind that you'll need somewhere roomy to store the boiler's cylinder and water tank.

The ultimate combination

If you're looking for a boiler that's highly energy efficient, a combi (combination) boiler might be the solution. They can be used to heat the home as well as its water, saving you a wedge on heating bills. Their compact size makes them ideal for even the smallest of properties, and since they use the mains to heat water up, you won't have to make space for a cumbersome water tank or cylinder. Another plus is that because they can instantly heat the water you need, you won't have to wait around for that warm shower.

Yet there are a few drawbacks to consider. You can only have one shower or bath running at once in your home, so if you've got a larger property with a few bathrooms, this might not be the right choice for you. Also, a combi boiler won't work effectively if the mains water pressure isn't at a certain level


Settle in between with a system boiler

A system boiler is like the middle ground between a conventional and a combi boiler. Although it's more compact than a conventional one because it doesn't need a water tank, you'll still have to make room for a cylinder somewhere in your home. However, unlike a combi boiler, it's a great option for properties with a few bathrooms

You can use system boilers with solar heating systems to maximise energy efficiency and further cut your heating bills, while the lack of a tank makes them less hassle to maintain and less susceptible to damage from leaks or frost. Installation won't be too much of an issue either, because the majority of the boiler's parts are already integrated within its system.

Just bear in mind that you'll only be able to heat a certain amount of water at a time, and because system boilers can lose heat, you'll have to insulate yours well.

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Heatable is registered in England and Wales No. 08804726 (VAT No. GB205805920 ). Trading address is 1 Station Road, Great Sankey, Warrington, Cheshire, WA5 1RH. Heatable acts as a credit broker (not as a lender) and offers credit products through a panel of lenders. Heatable is authorised and regulated by the Financial Conduct Authority (reference no. 805259).

[1] Price based on a like for like combi swap in a 2 bed, 1 bathroom terraced home with a standard flue

[*] Installation dates are subject to installer availability

[¹] only available on combi boiler installations