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A boiler is the engine room of a heating system,and is likely to be one of the most expensive appliances in your home that you know least about.

A boiler heats the water that circulates around your radiators to keep you warm. Some boilers i.e. ‘Combi' boilers also provide you with instanateous hot water to your taps, whereas others ‘System' or ‘Open Vent'boilers are connected to a hot water cylinder and heats your water for your taps via the cylinder.

Gas or oil Boilers come in 2 forms:

  • a 'Combi' boiler that provides both heated water for your radiators  and hot water for your taps

Typically boilers burn gas or oil to heat water, Modern boilers known as ‘condensing boilers', do this in the most efficient way possible. The types of boilers described above are available in ‘condensing' forms e.g. Combi condensing boiler, System condensing boiler and Open Vent Condensing boiler.

Since 2005 (2007 for oil) it became part of legislation that all new boilers installed have to be Condensing boilers, except in exceptional circumstances. If you have a 25 year old boiler that clanks away in a cupboard somewhere, don't worry the Boiler police won't be coming around to confiscate it. However you could be saving  money on your fuel bills (up to 35%) by getting it changed, not to mention helping the environment as condensing boilers are more efficient.

Further information:

Find out more about boilers.

Combi Condensing Boilers


System Condensing Boilers


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