Image of a man next to his boiler
Image of a man next to his boiler

The importance of an energy efficient boiler

Learn all about how a new, energy-efficient boiler can help you save on your energy consumption.

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Will a new boiler save energy and lower my heating bills?

A new A-rated boiler is definitely more energy efficient than an older one you may have had for years. Gas boiler efficiency is about how much fuel it uses to heat your home. If your boiler is old, it might not be efficient and could cost you more money to heat your home.

Save up to £5801 a year with our most efficient gas boilers from Worcester Bosch and Ideal. And if you need a quick replacement, get a quote and get it installed from as little as 48 hours2.

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The benefits of a new boiler

Save on your energy bills

New energy-efficient boilers can significantly reduce carbon emissions and reduce your energy bills by up to £5801 a year.

Why condensing boilers?

All our boilers are condensing, making them among the most efficient options in 2024.

What type of boiler?

When choosing a new boiler, you'll need to consider your property, family size, and boiler type. We'll help you find the best fit.

Are new boilers more efficient?

Your boiler provides hot water all year and heats your home in winter, making up half of your yearly energy expenses. So it's important to have the highest-efficiency boiler your budget will allow.

New boilers are A-rated and have a high efficiency of 90%. In contrast, older boilers can have an efficiency as low as 70%, leading to higher energy costs.

All new boilers come with an ErP rating sticker, usually on the packaging they come with. To find the model number of your boiler, check the front panel flap. If your boiler is old or missing the sticker, you can check the PCDC database to learn about its efficiency.

Top energy efficient boilers for 2024

We have a wide range of energy-efficient boilers, and here are just a few that you might be interested in learning more about.

One of our most efficient and powerful boilers provides you with hot water in an instant, even if you have low water pressure. This compact but mighty boiler will not only fit nicely into a kitchen cupboard, it'll also help you save on your energy bills.
If you're looking for an energy-efficient boiler with great power and you have low water pressure, this could be the boiler for you.

What is a condensing boiler?

The goal of a condensing boiler is to heat your home and water system as quickly and environmentally friendly as possible. All of the boilers we install are condensing, and they have a high energy efficiency rating because they turn the condensation of water vapour into heat. This means that the fuel you use will last longer, helping you to use less energy and saving on your energy bills.

Image of an ErP label
Image of an ErP label

What does my ErP rating mean?

The Energy Related Products Directive (ErP) was established to improve energy efficiency and reduce carbon emissions for boilers, combi boilers, water heaters, and other heating systems up to 400 kW. Boiler efficiency ratings in the UK range from A to G, with A being the most energy-efficient boiler.

Choosing an A rating means you'll be opting for the most energy-efficient boiler, helping to lower your energy bills compared to a G-rated model in a similar home. Hopefully the ErP rating label will be familiar to you as it's used on other appliances, such as fridges, washing machines, and ovens, making it easier for you to identify the energy-efficiency level you want and to be able to make comparisons before making a purchase.

Will a higher ErP boiler lower my energy bills?

By switching from a B-rated boiler to an A, you won't see much impact on your energy bills. But if you’re upgrading from a much older model, you could see a change in how much you are spending.

As an example, if you live in a detached house and are upgrading from a G-rated boiler to an A, you could save around £5801 a year on your energy bills. Save money and help the planet by using a more efficient boiler that reduces your carbon footprint. We guarantee that our Worcester Bosch boilers have an efficiency of up to 94%.

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Boiler ratings

  • A-rated boiler
    90% + energy efficiency
  • B-rated boiler
    86-90% energy efficiency
  • C-rated boiler
    82-86% energy efficiency
  • D-rated boiler
    78-82% energy efficiency
  • E-rated boiler
    74-78% energy efficiency
  • F-rated boiler
    70-74% energy efficiency
  • G-rated boiler
    Below 70% energy efficiency

What is the SEDBUK rating?

With the help of boiler manufacturers, the SEDBUK (Seasonal Efficiency of a Domestic Boiler in the UK) system for comparison was developed in support of the UK Government's energy efficiency best practice plan. Introduced in 1999, with updates in 2005 and 2009, SEDBUK lets you compare different boiler models impartially. Instead of the current ErP letter-based rating, SEDBUK gave a percentage, which measured the amount of energy used against energy wasted. For example, a SEDBUK rating of 80% shows that the appliance uses 80% of the energy produced and wastes 20%. These days, all boiler models must have a SEDBUK rating of 92% or greater, with our energy-efficient boilers having a rating of 94%.

Savings based on your home and boiler rating

Finding a boiler's efficiency means learning about how much fuel it wastes while heating your water temperature. These calculations are used to give each boiler its ErP rating. As previously mentioned, the letters are from A to G, with A being the most efficient and G the least efficient.

Discover potential energy bill savings in England, Scotland, or Wales by considering your home type and current boiler and replacing it with one of our energy-saving boilers from Worcester Bosch or Ideal.

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Image of a boiler
Image of a boiler

How much more efficient is a new boiler?

Well-maintained modern boilers burn their fuel more efficiently, but they lose an amount of heat when hot gases escape up the flue. The flue is a pipe that eliminates fumes and brings fresh air into the boiler.

New boilers are more efficient than old ones because they are condensing. This means they can turn more waste gas heat into hot water for your central heating.

Most modern boilers have a good energy efficiency rating, but it's difficult to compare them based on this alone. That's why some people continue to use the older SEDBUK rating process, as it provides more accurate information.

How efficient is a 20 year old boiler?

It's possible for boilers to last 15 years or maybe longer, but over time they'll become less energy-efficient and may need major repairs to keep working effectively, with parts that could be costly depending on what goes wrong, like overheating, boiler pressure, and leaks. So to reduce your heating bills over the long term, invest in a new energy-efficient boiler that'll keep you protected with a 10-year manufacturer's guarantee, and you'll also be doing your bit for the environment by lowering your home's carbon emissions.

Boiler flow temperature

The most energy-efficient combi boiler can be made to work harder to reduce your energy costs by lowering the boiler flow temperature. Most new combi's usually have a boiler flow temperature set between 70ºc and 80ºc but this wastes energy. The most efficient boiler temperature is 60ºc or lower.

This won't change your thermostat's temperature. It'll just take longer to reach your desired temperature. But the good thing is that it will save gas and make your boiler more energy-efficient.

Learm more about boiler flow
Image of a man on his laptop
Image of a man on his laptop

Gas or electric boilers?

Which one will work best for you?

Most UK households use energy-efficient, condensing gas boilers to heat water, which then passes to radiators and taps. We offer three different types of boilers: combi boilers, regular boilers, and system boilers. Electric boilers could be more expensive to run but are a great alternative if you don't have mains gas. They still heat your hot water and radiators, but instead they convert electricity into heat. Learn more in our guide to comparing gas and electric boilers to determine which is the best energy-efficient boiler for your home.

What else can I do to save energy?

Include a smart thermostat to efficiently heat your home, like the Worcester Bosch EasyControl. It can help you save even more energy and improve the control of your heating. You should service your boiler annually to keep it running well and efficiently. When buying a new boiler, think about getting a 3-year service plan to keep it working well and maintain the warranty.

FAQs

When it comes to saving energy, are combi boilers the best choice?

Although combi boilers are known for being energy-efficient, it's important to keep in mind that the amount of efficiency can vary depending on the make and model and the suitability for your home. Our GreenStar Worcester Bosch boilers have a guaranteed 94% efficiency rate, which makes them one of the most energy-efficient boilers you can get. If you have a larger home with multiple bathrooms, you may need a system boiler or, if you need lots of hot water, a regular boiler.

Which boiler is the cheapest to run?

Our A-rated Greenstar Worchester Bosch and Ideal boilers are some of the most energy-efficient boilers on the market, making them cheaper to run and reducing your energy costs.

How do I maintain an energy-efficient boiler?

Regular service is needed to keep an energy-efficient boiler in optimum condition. Keeping the pressure in the boiler maintained, making sure there are no obstacles in the way of the boiler, and having a Gas Safe-registered engineer service the boiler once a year. Visit our boiler servicing page for everything you need to know about boiler services.

Can I get funding from a Grants or Scheme?

We don't currently have any grants or schemes for upgrading your current boiler, but there are a number of different grants and schemes that could help with the energy efficiency of your home, from loft, cavity, and solid wall insulation to an air source heat pump or solar panels. Try our online grant finder to check if you're eligible.

Need help solving a boiler problem?

If you've got a problem with your boiler, why not check if you could resolve it with our handy guide to helping fix some of the most common boiler issues? If you're still experiencing problems, take a look at our boiler cover options or contact a Gas Safe-registered engineer.

The legal stuff

1 Saving information for boilers in the UK is provided by the Energy Saving Trust, based on a detached house with a boiler rating of G.

2 If you accept the terms and conditions on your quote and either make an upfront payment or accept the terms and conditions of your finance agreement before noon. By requesting installation within your 14-day cooling-off period, you also waive your statutory right to cancel your contract.

 

A little help and advice