boiler efficiency

How Efficient Is Your Boiler?

Are you sick of having to deal with high energy bills? It might be time to take a closer look at your boiler. If your boiler is not working efficiently it could be using too much gas, which will result in unnecessarily expensive running costs.

In this guide, I’ll be explain how boiler efficiency is calculated and share some benefits of getting a more energy efficient boiler. If you have any questions, give Quantum Gas Engineering a call on 0203 633 2322.

How Is The Energy Efficiency Of A Boiler Calculated?

Up until 2015, boiler efficiency was calculated using SEDBUK, which stands for Seasonal Efficiency of Domestic Boilers in the UK. It’s a simple rating system which tells consumers how efficiently a boiler can turn gas into heat.

There are also two types of SEDBUK ratings. SEDBUK 2005, which used a letter system (A to G) and SEDBUK 2009 which showed efficiency as a percentage. These systems both sorted boilers into one of seven categories:

• Band A (Above 90% efficiency)
• Band B (Between 86 to 90% efficiency)
• Band C (Between 86 to 90% efficiency)
• Band D (Between 86 to 90% efficiency)
• Band E (Between 86 to 90% efficiency)
• Band F (Between 86 to 90% efficiency)
• Band G (Below 70% efficiency)

In 2015, the scheme was replaced by the ErP directive, which includes two parts:
1. Energy labelling for any product which produces below 70kW. The labels outline the efficiency band of a heating product with classifications between A++ and G
2. Ecodesign for products between 70kW and 400kW, which includes space heaters, water heaters, and storage cylinders.

The Ecodesign aspect of the scheme means that old style non-condensing boilers are going to be phased out. These types of boilers are not as energy efficient as modern boilers (more on that in a moment).

It also means that boilers must meet stringent standards when it comes to energy efficiency. Under the ErP directive, all boilers up to 400kW must have a minimum useful efficiency of 86% when under 30% load and minimum useful efficiency of 94% at 100% load. They must also have minimum gross seasonal efficiency of 92.5%. In simple terms, this means that they must turn gas into heat extremely efficiently.

How Installing A New Boiler Makes Improves Energy Efficiency

Modern boilers are more efficient for several reasons. However, the main reason is that they are ‘condensing’ boilers. This means they can condense water vapour found in the boiler’s exhaust gases, recovering the heat these gases contain.

This captured heat is used to heat your home, meaning less energy is required to reach your desired temperature. This condensed vapour that is collected is drained from the system in liquid form.

New boilers also have a variety of other technological advancements which improve energy efficiency. This includes highly accurate thermostats, improved heat exchangers, room by room heating settings, sophisticated timers, and sensors.

How Much Money Can Be Saved By Upgrading Your Boiler?

As it turns out, a boiler upgrade can save you an incredible amount of money. The Energy Savings Trust has compiled estimates on how much you might save. To provide a quick example: if you live in a detached house and upgrade from an old ‘G’ grade boiler to an energy efficient appliance, you could save £315 a year.

My Boiler Still Works Fine, Do I Really Need To Replace It?

If you have a boiler that is over 10 years old or a boiler with a low SEDBUK rating, then you may obtain significant cost savings by upgrading. If you are unsure, ask a boiler engineer to assess your heating system to tell you if an upgrade will be worthwhile.

Other Advantages Of Upgrading Your Boiler

Aside from saving money, there are several other reasons too upgrade your old boiler:

Compact size
If you decide to upgrade, you can buy a new combi boiler. This type of boiler heats water on demand and is extremely energy efficient. It doesn’t have a water tank, so upgrading to a combi boiler can free up some space in your property. The additional space could be used for additional storage or to free up room for a renovation.

Improved reliability and performance
New boilers tend to be far more reliable than old models. You’ll experience fewer breakdowns and your home will consistently warm and comfortable.

Easy to use
Boilers have come a long way in the past decade. Some models now have large LED displays which make adjusting the temperature, setting timers, or configuring the boiler simple. It’s also possible to purchase ‘smart’ boilers which work in conjunction with a smart phone app, allowing you to adjust your home’s heating remotely.

Do your bit for the environment
The improved efficiency of modern boilers means that they release less CO2 emissions. This reduces your carbon footprint and your contribution to human-induced climate change.

Thanks for reading. If you have any questions about the efficiency of new boilers give Quantum Gas Engineering a call on 0203 633 2322.

Quantum Gas Engineering Ltd. Are Accredited Viessmann installers.

Interested In Learning More? Contact Quantum Gas Engineering

For more information on Vaillant boiler installations in Primrose Hill, give Quantum Gas Engineering Ltd a call on 0203 633 2322 or email us at