Combi (or combination) boilers have everything needed to heat your radiators and deliver hot water to your taps. The boiler is a compact unit which means it is easy to fit in any home as there is no need for a hot water cylinder or water tanks in the loft.

How it works

When you turn on a hot tap your combi boiler heats water instantly. The water comes straight from the mains, so the flow rate at the tap is usually very good. This all means that because the boiler only heats the water you need, when you need it, it is extremely energy efficient.

Suitable for:

Combi boilers are ideally suited to homes with only one bathroom, this is because flow of hot water can be reduced if more than one hot tap is running at the same time. A system boiler may be more suitable for homes with several bathrooms, low mains water pressure or a high demand for hot water.

What is Boiler Plus?

Boiler Plus brought in a change to the Buildings Regulations in 2018 aiming to improve the way people use energy in their homes by giving them a greater choice on how to maximise energy efficiency. This meant that all boiler installations must include a timer and room thermostat.  Combi boiler installations must also include one of the following extra energy efficiency measures:

  • Weather compensation
  • Load compensation
  • Flue gas heat recovery
  • Smart control with automation and optimisations

Looking for a different type of boiler?

Find out more about Heat Only Boilers and System Boilers.