Buying an Electric Boiler: What You Need to Know
Electric boilers don't take up much space, operate quietly and are often cheaper to install than gas and oil boilers. However, they’re only suitable for smaller homes and flats.
What is an electric boiler?
Electric boilers provide central heating and domestic hot water to properties without burning any fuel, such as oil and gas. Instead, they only use electricity, in a very similar way to a kettle. Electric boilers are often compact units that are easily installed and don't require a flue or condensate pipe as they don't produce any waste gases.
There are several electric boiler types available:
|Electric Boiler Type||How it Works|
|Direct||Heats water on demand and doesn't store it in a cylinder, much like a combi boiler.|
|Storage||Stores water in a hot water tank that's either housed within the unit or elsewhere in the property.|
|Combined Primary Storage Unit (CPSU)||Often the largest type of electric boiler, they store hot water within the unit.|
|Dry Core Storage||Heats bricks overnight, then during the day the heat is released into the water and used for central heating and domestic hot water.|
The units are much simpler than other boiler types with far fewer moving parts, making them much less likely to develop a fault.
Advantages of an electric boiler?
For smaller homes that suit an electric boiler, there are many benefits.
When comparing installation quotes, you'll find that an electric boiler is often cheaper to install than gas and oil boilers. This is because electric boilers don't produce any waste so there's no need for a flue or condensate pipe, which also removes the need for additional piping too.
No risk of a carbon monoxide leak
Unlike gas and oil that both produce carbon monoxide when burnt, electric boilers don't burn any fuel, removing the risk of a carbon monoxide leak altogether.
No annual service
Electric boilers don't need to be serviced annually as there are very few moving parts. Not having to arrange a service will save you between £50 – £160 every year.
An electric boiler can be installed on just about any wall around the home, whereas a gas or oil boiler needs to be on an external wall – giving you greater flexibility. This is because electric boilers don't produce any harmful waste gases or water during operation, so there's no need for a flue or condensate pipe.
Compatible with solar
Running an electric boiler with solar PV makes it possible to power the boiler with free renewable solar energy to reduce the running costs. A solar thermal system can also be used to heat the hot water in a cylinder.
Electric boiler problems
While electric boilers are a simpler alternative to gas and oil, they don't come without their problems.
High running costs
Electricity is much more expensive than gas which could see your energy bills increase. While the running costs might be higher, you will be saving on an annual service and are less likely to need any repairs. Compare the costs in Electric Boilers vs Gas Boilers.
You can combat the expensive running costs with either an Economy 7 or Economy 10 tariff, which both offer reduced prices for electricity during the night or by running an electric boiler with solar energy generated by solar PV.
Less hot water
An electric boiler isn't the best option for larger homes as they're unable to meet the higher demand for central heating and hot water.
When it comes to finding an electric boiler with the right output, you want 1.5 kW per radiator in your home. So, if there are 8 radiators in your home, you should install an electric boiler with an output rating of at least 12 kW.
3. Power cuts
A power cut will leave your home without heating and hot water until it's back up and running but this isn't a problem exclusive to electric boilers. All modern boilers are made up of many electrical components, including the printed circuit board (PCB) which is considered the 'brain' of the boiler, so during a power cut a gas boiler wouldn't work either.
4. Could blow the fuse
Before deciding on an electric boiler, it's very important to know the size of the fuse in your home, otherwise there's a strong chance it could blow the fuse.
A fuse delivers power into the home and many UK homes, particularly older properties, have either a 30 or 60 amp fuse. A typical electric boiler will use 48 amps, which is enough to blow a 30 amp fuse or not leave much room for other electrical appliances to run with a 60 amp fuse.
It's possible to have an 80 or 100 amp fuse fitted into UK homes and it's worth consulting an electrician for their opinion before investing in an electric boiler.
Electric boiler efficiency explained
When comparing electric boilers, the efficiency ratings can lead to some confusion. It's hard to find an electric boiler that doesn't have an efficiency of 99-100%, yet the ErP rating, a European energy rating system, is often C or D on a scale of A+++ (highest efficiency level) down to a G. Gas and oil boilers, on the other hand, are frequently given A-ratings despite having an efficiency of around 89% – 94%.
So, why is the ErP rating of electric boilers so low? The answer lies in the way electricity is most commonly generated in the UK.
While generating electricity using renewable technology is on the rise in the UK, the majority is still produced using fossil fuels such as gas and oil. For this reason, electricity is considered a carbon intensive fuel.
As a carbon intensive fuel, electricity is more expensive than natural gas, LPG and oil. The only way for the carbon intensity and cost of electricity to drop is for more energy suppliers to turn to renewable electricity generation.
Fortunately, the National Grid believe this could happen as early as 2025: "We believe that by 2025 we will be able to fully operate Great Britain's electricity system with zero carbon."
Find out more by reading Electric Boiler Efficiency Explained.
Get FREE Quotes
Homes best suited for an electric boiler?
The common home heating solution for properties off the gas network is oil but that means having somewhere to store the oil. Electric boilers are an efficient alternative that don't take up much space.
However, as electric boilers can only provide a limited amount of hot water, they're not the best home heating solution for larger properties. If you live in a large home off the grid and are looking for an alternative to an oil boiler, then there are several renewable alternatives.
As well as home of the gas network, electric boilers are also well suited to flats. All gas boilers need a flue to expel waste gases out of the property but Boiler Flue Regulations state that they must be a certain distance away from windows and doors to ensure the gases don't go into your own home or a neighbour's home. Meeting these flue regulations can be particularly difficult for flats.
With an oil boiler also being out of the question for flats, as they also need a flue, not to mention a storage tank for the oil, an electric boiler is the perfect solution.
Flats tend to be the ideal size for an electric boiler to meet the heating and hot water demands, plus they're compact in size so won't take up much space – which can be precious in a smaller flat.
Who can install an electric boiler?
When replacing a gas boiler with an electric boiler, you'll need to hire a Gas Safe registered engineer to remove the gas boiler. They will also remove the flue, condensate pipe and cap the gas line as these aren't needed for an electric boiler.
The Gas Safe registered engineer should also be able to install the electric boiler but once it's up on the wall, an electrician will then be needed to take care of the final bits of wiring – your heating engineer might be able to recommend someone.
Electric boiler installation quotes
When looking to have an electric boiler installed, we highly recommend comparing installation quotes from several installers. Comparing quotes gives you the greatest chance of finding the best deal available in your local area.
To make finding engineers who can provide quotes easier, take a couple of minutes to complete our simple online form and you'll get free quotes from up to 3 electric boiler installers based near you.
Get FREE Quotes