What boiler do I have?

Learn how to get the most out of your kit

Every home has a boiler. But not every home has the same type.

The type of boiler you have affects how it works, how it is cared for and how it is repaired.

Knowing which one you have will make it easier to keep your home in tip-top shape – and give our experts the information they need to perform the right service or maintenance.

Conventional boiler diagram

Conventional boilers

If you have a water cylinder and a storage tank then you are using what is known as a conventional boiler.

Some people might refer to them as a vent or ‘regular’ boiler and they are most common in larger properties with bigger hot water demands as gallons of hot water can be accessed at one time via the storage tank.

Unfortunately, once this supply runs out it can take a while to replenish and as the boiler uses a cylinder and tank it requires more storage space in your home.

It also needs to be connected to a cold water storage tank, which usually goes in your loft, and may not offer quite the same energy efficiency as some other boilers.


Brits love a combi-boiler. In fact, they’re the most common type you’ll find in UK homes.

These boilers do not use water cylinders or storage tanks so they’re far easier to fit in your home and supply hot water on demand direct from the mains.

This means you get instant hot water but turn on too many taps at once and you might exceed its capacity.

Maintaining a boiler can be a little tricky if you don’t know what you’re doing. But our expert engineers are always here to help.

You can also put fears of weak showers to rest as combi-boilers deliver hot water at the same pressure as the mains so you get a strong, powerful shower without fitting any pumps.

Combi-boilers diagram

System boilers diagram

System boilers

If you have a water cylinder but not storage tank then your home is using a system boiler.

Essentially a middle-ground between combi-boilers and conventional boilers, they are also known as sealed systems and allow you to draw hot water from multiple taps at once.

If you use up all the hot water in the cylinder then you’ll have to wait for it to reheat though so don’t go overboard.

You’ll also need to find somewhere to store the cylinder (most people use the airing cupboard) but at least you won’t need to clear space for the storage tank.

Also in this section

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