What’s the difference between a conventional and combination boiler?

Conventional boilers - also called open vent or regular boilers - have both a cylinder and a tank. Combination (or combi) boilers provide heat and hot water without a water tank or cylinder. This is the most popular kind of boiler in the UK, and you can pick either a gas or electric one.

Which one’s best for me?

Conventional boilers mean you can get hot water from multiple taps at the same time. But the hot water can run out and you’ll have to wait for it to reheat. You also need to have room for both the cylinder (for example in a large cupboard) and the tank (like a loft or attic).

Combi boilers mean you get unlimited heat and hot water whenever you need it. There’s no need for a tank in your loft and they don’t take up much space. But if you need hot water from more than one tap at a time the water pressure might be reduced.

Find out more about boilers

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