Boiler basics

Buying a new boiler isn’t as easy as it may seem. You may have just gone onto the British Gas website, had a brief look at the boilers on offer and decided that that is it. Not so my friend. Now you must decide what type of boiler you want. For there are many, and you might end up getting the wrong one.

Firstly there is the Combination boiler. This is the most popular type of boiler, now in around 70 per cent of homes because they provide both central heating and hot water without the need for a separate tank to store water. They can be tucked away into small spaces such as kitchen cabinets - perfect for smaller homes with only one bathroom. They provide instant, unlimited hot water and are compact, but are unable to run more than one shower or bath at the same time and the hot water flow rate will be lower than with other types of boiler.

The next main type of boiler is called a System boiler. These are also known as a “sealed system boilers” and they provide central heating and hot water through a storage cylinder housed in an airing cupboard so there’s no need for a water tank in the loft, as with an open vent boiler. System boilers are ideally suited to larger homes with more than one bathroom or en suites housing families who’ll want a lot of hot water and the ability to run more than one shower or bath at a time. However, hot water won’t be instant and once the storage cylinder has run out you’ll need to wait for the water to reheat.

The final type is an open vent boiler. Also known as a heating only boiler, this one provides central heating and hot water through a boiler, a storage cylinder and water tanks in your loft. This is quite a dated system and most people doing a full central heating overhaul will opt to switch to a sealed system.

Open vent boilers are good for larger homes with an existing open vent boiler. They have the same advantages as system boilers such as a high flow rate and being able to run more than one shower or bath at a time. But they take up more space than a system boiler and also have the same disadvantages such as having to wait for the water to reheat once it has run out. For this reason, many people choose to have them replaced.

You can find examples of all the above boilers on the British Gas website.