What is a heat only boiler?

A heat only boiler works works with a small expansion tank and a larger cold water storage cistern usually located in your loft space. If you have a heat only boiler which you want to replace, the best option may be to replace it with a newer, more efficient model. This is because the system may not cope with the higher water pressure from a combi boiler or system boiler. Heat only boilers are also a good solution if your home has low water pressure or you have several bathrooms.

How it works

Heat only boilers work with two water tanks in the loft, a hot water storage cylinder and a pump to push the hot water around the system, plus a timer and room thermostat. The way it works if that one of the tanks draws water from the mains which fills the hot water cylinder, this is then heated by the boiler to supply all your hot water to all the taps in the home. The other tank, known as the feed and expansion tank, is usually smaller and keeps the water in the heating system at the correct level. It also allows for expansion in both tanks when the water gets hot.

Suitable for:

The real benefit of a heat only boiler is that several hot water taps can be run at the same time, making it the perfect option for busy families and homes with several bathrooms.

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, including heat only systems, must include a timer and room thermostat.

Compatible with:

Heat only boilers are compatible with Megaflo Eco cylinders

Looking for a different type of boiler?

Find out more about Combi Boilers and System Boilers.