How energy efficient is my boiler?

How efficient is your boiler when it comes to turning fuel into heat? If you’ve got a modern A-rated condensing boiler then it’s going to be highly efficient. We’re talking 90% or more. But it’s a different story altogether if you’ve got an old inefficient boiler. In fact it could be wasting as much as 30% fuel compared to just 10% or less with a new high efficiency boiler. 

How energy efficient is your home?The fact is central heating is one of the biggest energy costs for homeowners. Boilers, if you didn’t already know, count for around 55-60% of your energy bills. That’s a big old chunk.

New legislation which came into effect in April 2018 requires that all new gas boilers installed into domestic homes must have an efficiency rating of at least 92%.

Replacing your old inefficient G-rated boiler with a new A-rated condensing gas boiler could see you reduce your heating bills by as much as £210 a year if you live in a semi-detached house and more (£320) if you live in a detached home. The savings aren’t as significant if you live in a mid terrace house (£180) or a mid floor flat (£100).

So you may be wondering how to find out how efficient your boiler is? Boiler efficiency ratings used to be calculated using a system called Seasonal Efficiency of Domestic Boilers in the UK. Also known as SEDBUK for short the system measured how efficient boilers are at converting fuel (gas and oil) into heat. SEDBUK Ratings ranged from A-G and had an efficiency percentage.

This system has since been replaced by the Energy related Products directive (ErP). Introduced in 2015, the ErP system also provides an efficiency percentage but rates products from A++ to G, with G being the least efficient a boiler can be.

To determine how efficient your boiler is visit

Most boilers with a SEDBUK Rating of A and B will be condensing boilers and waste a low percentage of fuel compared to older models. Boilers with a rating of C and G will waste the most fuel and are prime candidates for the boiler grants scheme.

Comparing boilers

Not every boiler delivers the same level of energy efficiency. To be sure you’re getting the best boiler for your budget it’s important to compare several models on a like for like basis.

Boiler Guide’s comparison tool is a quick and easy way to compare up to 4 different boilers at a time on their most important features such as energy efficiency, power output, length of warranty and typical prices.

With a few clicks you can compare both gas and oil boilers from all the leading UK manufacturers (including Combi, System and Regular models) and even request installation quotes from Gas Safe registered engineers.

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Benefits of installing a new boiler

  • Save money & make your home more energy efficient
  • New A-rated boilers waste less energy
  • They average family could reduce their annual energy bill by up to £320
  • Modern condensing boilers are at least 90% efficient
  • With a G-rated boiler you could be wasting around 30p in every £1 you spend to heat your home – compared to around 10p with a 90% efficient model

Isn’t it time you switched to a more efficient form of heating? Click on the ‘Get a quote now’ button below to source free quotes for a new boiler replacement from Gas Safe Registered heating engineers in your area.

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