How do I know what type of boiler I have?
Updated: May 19
We reveal the three main types of boiler and how you can tell which one you've got at home.
Generally speaking, there are 3 main types of gas boiler. The common names for these are combination boilers, system boilers and regular boilers (also known as conventional or heat only boilers).
What is a combi boiler?
A combination boiler, or combi boiler, is an appliance that is installed on a sealed heating system without any tanks in the loft. The boiler heats hot water on demand as it runs through the appliance, and therefore doesn’t need a hot water cylinder.
This is a very efficient way of heating hot water as it only heats water that is being used when the taps are on. Combination boilers have been around for nearly 30 years and are the most common type of boiler installed in properties today. They are the perfect solution for properties with low hot water demand where there is adequate flow to run the outlets required.
Combination boilers are typically most suitable for houses where there is only one bathroom likely to be in use at any one time, and therefore a store of hot water is not required.
What is a system boiler and a regular boiler?
There is little difference between system and regular boilers. Both types are installed alongside a hot water cylinder making them ideal for use in larger properties where the demand for heating and hot water is higher.
Typically, the main difference between these boilers is that a system boiler will have a pressure gauge built into the appliance and will need to be manually topped up (see our guide to topping up boiler pressure here).
Regular boilers have been around the longest and will often be installed on to open-vented systems where the heating system is fed from a cistern installed in the loft. System boilers will often have the heating pump built into them, whereas a regular boiler will use an external pump to circulate water throughout the heating system.
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