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Do you know how energy efficient your boiler really is?

When it comes to heating a home, we often hear from customers who want a boiler that’s going to perform well, whilst costing them as little as possible to run. But do you know what makes an efficient boiler, and what the true cost of an older system is on your utility bills?

What does it mean when we talk about a boiler’s energy efficiency?

For most of us, our gas boilers contribute to the majority of our monthly energy bills, particularly throughout the winter months, so ensuring we are getting the results we are paying for is key to protecting the pennies.

When talking about a gas boiler’s efficiency, we are referring to the total amount of energy out of the 100% produced that actually goes into heating your home, as some energy will be lost during the combustion process. Unfortunately, due to how boilers operate, no boiler is ever 100% energy efficient, however modern gas boilers can achieve extremely high energy efficiency ratings.

So if your boiler is operating at 60% efficiency, you will be losing 40% of the energy produced, whereas an extremely efficient boiler operating at 90% will only be losing 10% of the energy produced – and this difference will make a substantial impact on your energy bills over the course of a month. Regardless of your boiler’s output, you’ll still be paying for 100% of that energy bill!

So how is a gas boilers efficiency actually measured?

There are two main ways in which the efficiency of gas boilers is measured – by using the ‘Energy-Related Products’ (ERP) measurement, or the ‘Seasonal Efficiency of a Domestic Boiler in the UK’ (SEBDUK) scale. Whilst these measurements vary slightly, they each tell us the approximate efficiency of a gas boiler using a rating scale from A to D (ERP) or A to G (SEBDUK).

Due to laws surrounding energy efficiency, all new gas boilers that are produced in the UK must having a rating of ‘A’ which will be clearly indicated using the ERP rating scale – good news for our wallets and our carbon footprint!

How to ensure maximum energy efficiency of your gas boiler.

If your boiler is relatively new then chances are, it is an energy efficient appliance, however ensuring that it is regularly maintained will keep it in tip-top shape and keep you getting the best performance possible. Over time it’s likely that elements of your boiler may need repairing or replacing to make certain that it’s functioning optimally and by guaranteeing your boiler is serviced annually, you can rest assured that you are getting the best energy output possible.

My boiler is quite old – should I replace it?

Due to changes in the law in the UK that came into effect in 2007, all boilers produced since this date are known as ‘condensing’ boilers. Due to the design of the condensing boiler, they are able to utilise the hot gasses that are created and expelled during the combustion process rather than simply letting that heat be wasted, therefore at a minimum these boilers operate at around 90% efficiency.

So, if your boiler was installed before 2007, it could be incredibly beneficial to upgrade your boiler to a newer energy efficient model. Boilers installed before this cut off could have ratings as low as G on the SEBDUK scale, meaning they operate at around only 60% efficiency, causing you to spend a lot more money than necessary to heat your home.

Whether it’s for protecting your pennies, or for protecting the environment, we should all know whether our gas boilers are performing optimally. To schedule your annual service or enquire about getting your new energy efficient boiler installed, contact George Kitchen at or alternatively you can call us on 07496 901102. Our team of experts are on hand to talk you through the options to best suit you and your home to ensure you are getting the very best out of your appliances.


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