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What is a combi boiler?

What is a combi boiler?

A combi boiler provides heating and hot water directly from the boiler.

Here’s an example of a central heating and hot water system layout using a combi boiler:

Combi boiler layout Enlarge image

A combi (or combination) boiler is an ingenious space-saving idea, and an increasingly popular choice in UK homes. In fact, combis now account for well over half of all the new domestic boilers installed in Britain every year.

A combi boiler is both a high-efficiency water heater and a central heating boiler, combined (hence the name) within one compact unit. Therefore, no separate hot water cylinder is required, offering space saving within the property.

Further benefits of a combi boiler includes hot water being delivered through your taps or shower at mains pressure. So you can enjoy powerful showering* without the need for a pump.

Another combi boiler benefit is that it can generally save you money on installation time and costs, since no tank in the roof space means less pipe work and a shorter installation time.

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Use our Find an Installer search to find combi boiler installers in your area.

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*A thermostatically-controlled shower safeguards against sudden changes in water temperature.

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