If you doubt that an electric boiler is the right choice for your home, it's high time you changed your mind. Since the UK government is planning to ban gas boiler installation by 2035, you should look to opt for alternatives now. How about considering an electric combi boiler this winter?
Together with heating water, electric combi boilers are designed to warm up your home which makes them a perfect choice for smaller properties.
For an informed boiler decision, you should consult a heating professional with proper expertise and certifications. However, searching for them on your own becomes an arduous and annoying task when you don't have hours to spare.
Fortunately, Boiler Guide can provide you with up to 3 stress-free quotes from registered engineers. Completing our form will take 30 seconds and bring you up to 3 reliable quotes to compare. Our service has no hidden charges and doesn't bind you to place any orders. Click below to get started.
An electric combi boiler operates by merging the tasks of heating water for central heating and providing hot water into a unified system. These boilers function by utilising a heating element and employing a design that allows more water to be heated at once.
The electric combi boiler comes equipped with temperature controls, enabling you to adjust the desired temperature for both central heating and hot water supply.
Electric combi boilers are one of the best small boilers for apartments or small homes with one bathroom, as they offer instant heating and hot water supply capabilities.
How does an electric combi boiler work?
Electric combi boilers are connected to both the main electricity supply and the main water supply of your home. The primary heat exchanger heats the water for central heating purposes, while the secondary plate heat exchanger warms the water for a hot water supply.
When you require hot water, cold water from the mains enters the secondary plate heat exchanger. The heating element also warms this water, and the resulting hot water is delivered directly to taps, showers, or other outlets in your home.
When you turn on the central heating, cold water from the mains enters the primary heat exchanger. The heating element heats the water as it passes over it. The heated water is then circulated through the central heating system, like radiators or underfloor heating, providing warmth throughout your home.
Electric combi boiler diagram
There is a heating element within the electric combi boiler responsible for warming the water. This element relies on electricity to generate heat. The boiler is connected to the main water supply of your home, ensuring a continuous flow of cold water.
Our electric combi boiler diagram below shows how this system operates as a whole.
If you're considering a boiler installation, you need to search for certified boiler installers who will provide actionable quotes. You could spend hours browsing and vetting each installer yourself if it's your dream pastime activity. Alternatively, you can gain access to the Boiler Guide network full of already vetted registered engineers.
Just spend less than a minute answering some easy questions about your home's heating needs and we'll take it from there. You'll get up to 3 free quotes to compare, and you're under no obligation to accept them. Click the button below to get started.
Electric combi boiler costs in the UK: prices in 2023
The cost of operating an electric combi boiler per kilowatt (kW) size can vary due to several factors, including the brand, model, and energy efficiency.
As a rule, the output rating of an electric combination boiler depends on the number of radiators in your home. Account for 1.5kW of power for each radiator to find out your home's heating capacity. If your home counts over 10 radiators, consider more powerful solutions like a gas boiler with higher output power.
Electric combi boiler running costs
It's worth mentioning that electricity tends to be more expensive than gas, which may result in higher running costs in the short term. That's why choosing a suitable electricity tariff plays a crucial role in the cost of running your electric boiler.
As of July 2023, the current energy price cap for electricity in the UK is £0.30/kWh. The pence per kWh depends on the energy supplier, the tariff itself, the meter type, and the region. It's advisable to contact your local energy supplier and compare tariffs to find the one that suits your situation.
Here are the estimated electric combi boiler running costs for various housing situations.
Number of radiators
Average yearly boiler running costs*
6kW electric combi boiler
9kW electric combi boiler
12kW electric combi boiler
15kW electric combi boiler
24kW electric combi boiler
*Assuming the boiler runs 8 hours a day including the above-mentioned electricity rate.
You can cut down on your electricity bills with tariffs like Economy 7 which is tailored for properties using electricity for heating and domestic hot water. By running your boiler at off-peak hours (between 12 a.m. and 7 a.m.), you can reduce your electricity bills by half.
Here's how Economy 7 compares to the current standard rate:
Economy 7 rate (off-peak)
Economy 7 rate (on-peak)
Standard electricity rate
Average price (pence/kWh)
*Based on Ofgem data from July 2023
However, such a tariff might not suit every homeowner's situation, so it's advisable to contact your local energy supplier and compare tariffs to find the one that suits you.
Electric combi boiler installation costs
Before thinking about boiler installation, you first need to purchase one. The upfront cost of an electric combi boiler largely depends on its power output, type, brand and model.
The most common electric combi boiler prices in the UK vary between £690 and £2,800.
The cost of installing an electric combi boiler can be influenced by various factors. Here are some commonly encountered factors that can impact the overall expense:
Power output. Generally, a higher power output boiler will incur a higher installation cost compared to a lower power output boiler.
Built-in cylinder. If your electric combi boiler includes a built-in cylinder, the installation cost will increase accordingly.
Location. Installing a boiler in a new location within your home typically costs more than replacing an existing boiler.
Labour costs. Labour costs for electric combi boiler installation can range from £500 to £2,000.
Brand and model. New combi boilers generally range from £690 to £2,800, depending on the brand and model, type and efficiency.
Type of boiler. Wall-mounted boilers with power outputs ranging from 3 to 15kW can command supply costs of £1,700 to £2,000. If you opt for a 12kW boiler without a built-in cylinder, your anticipated supply expenses would range from £900 to £1,500. Factoring in labour costs between £500 to £2,000, the overall estimated price for purchase and installation would average between £1,400 to £3,500.
On the other hand, if you go for a floor-standing boiler with a power rating of 10 to 18kW and an extended warranty period, you can expect to pay between £2,200 to £4,500. After considering the labour charges, this would result in a final cost ranging from £2,700 to £6,500.
Electric combi boiler installation typically ranges from £500 to £2,000, so with the new boiler costs you'll be looking at prices between £1,190 and £4,800.
Electric combi prices in the UK
Type of boiler
A boiler without a built-in cylinder
When investing this much in a boiler, you need a trusted and certified engineer who will ensure its safe and long-lasting operation. Browsing and vetting boiler installers on your own is a common decision, yet it adds stress and takes hours from your precious leisure time.
Fortunately, Boiler Guide can assist in hassle-free searches for boiler installers near you. Fill out our 30-second form and we'll take it from there. You'll receive up to 3 free quotes to compare with no obligation to place any orders. Click below to begin.
The more powerful the electric boiler, the higher the cost is to both install and run it. Boiler power is referred to as boiler output size and is measured in kilowatts (kW). What size combi boiler do I need is dependent on the size of your home and other factors such as the amount of radiators you have.
On average, a small boiler with 4kW costs approximately £600 and a larger boiler with 30kW would be upwards of £2,000. However, additional installation costs will vary depending on the installer you choose and the complexity of the installation.
Any homeowner who is looking to install a new electric boiler in their home would be well advised to get quotes from several different Gas Safe registered engineers. Spending just a few minutes getting free quotes from certified professionals can save you hundreds of pounds in the long run.
Our network of vetted and certified boiler engineers can help you get up to 3 free quotes to compare. It takes less than a minute to begin. This is the most convenient and time-saving way to be sure that you’re getting the best deal on a new boiler without any hassle or stress. Simply click the link below to get started.
The pros and cons of electric combi boilers can vary depending on several factors, such as the property size, the number of dwellers, and their energy consumption habits.
Let's look at the brightest advantages electric combi boilers have to offer.
Advantages of electric combi boilers
High energy efficiency. Electric boiler efficiency reaches 100% at the point of use, converting 100% of the energy they consume into heat. When comparing electric versus gas boilers, which are around 90-95% efficient at installation and may lose efficiency over time, electric boilers prove to be more efficient
No gas supply required. Electric combi boilers don’t require a gas supply, which can save space and installation costs.
Compact size. Electric combi boilers are generally smaller and more compact than gas boilers, making them ideal for smaller properties.
Quiet operation. Electric combi boilers operate quietly, making them ideal for properties where noise is a concern.
No direct carbon emissions. Electric combi boilers don’t produce any direct carbon emissions, making them a more environmentally friendly choice. Worth noting that for truly eco-friendly energy, you should be using your own renewable source or at least a green energy supplier.
Easy installation. Electric combi boilers don’t require flue pipes, which can save space and installation costs.
As you can see, there are many advantages to electric combi boilers. However, you should take this information with a pinch of salt and consider why an electric combi boiler might not be the best choice for your home.
Disadvantages of electric combi boilers
High upfront costs. Electric boilers generally have a higher initial cost compared to gas boilers.
Lower power output. Electric combi boilers typically have a lower power output compared to gas combi boilers, often up to 9kW. This may challenge meeting larger properties' heating and hot water demands.
High installation costs. Installation costs for electric boilers can vary depending on factors such as location, labour costs, boiler type, brand and model, and the inclusion of a built-in cylinder.
It is recommended to consult with a heating engineer to determine whether an electric combi boiler is the right choice for your specific situation.
There are several ways to find out if a heating engineer has proper expertise. One common, but time-consuming, way is by calling them individually. However, you'd have to spend hours vetting all of the local engineers in your area.
In less than the time it takes you to call a single installer, you could get up to 3 free boiler quotes from heating engineers in the Boiler Guide network. All you'd need to do is spend less than a minute answering some easy questions about your home's heating needs. We'll then take it from there and you'll soon have 3 reliable quotes to compare. Click the button below to get started.
There are several reputable electric combi boiler companies in the UK offering a range of boilers with sizes from 1kW up to 15kW.
Aztec electric combi boiler, Trianco
Warranty: 5 years
Output: 4kW, 6kW, 8kW, 10kW, 12kW
Trianco combi boilers come in Aztec Mini and Maxi models and can be easily controlled through the supplied digital, programmable WiFi thermostat. The Aztec combi boilers are designed for installation in utility rooms, and airing cupboards, or can sit flush with kitchen wall cabinets.
The boiler includes a 5.7cm BSP immersion heater connection. It allows a secondary heater installation to utilise solar energy from solar PV panels, potentially providing the equivalent of one to two baths of free hot water per day, depending on weather conditions. It delivers domestic hot water at a rate of up to 10 litres per minute and comes complete with a pump, auto air vent, expansion vessel, and pressure gauge.
Comet electric combi boiler, Electric Heating Company
Warranty: 2 years, 10 years for cylinder
Output: 9kW, 12kW, 14.4kW
Comet Electric Combi Boilers are suitable for homes with one bathroom. The boiler includes a duplex stainless steel hot water cylinder with a generous capacity of 140 litres. The standard warranty provided is for 2 years, and it offers a central heating maximum output of 12kW.
Electromax, Heatrae Sadia
Warranty: 2 years
Output: 6kW, 9kW, 11kW
Electrolux by Heatrae Sadia offers boiler options which are suitable for small to medium-sized homes with one or two bathrooms. This appliance combines an electric flow boiler with a direct unvented hot water cylinder. The duplex stainless steel hot water cylinder has a capacity of 180 litres. The dimensions of the Electromax are 1,476mm x 550mm x 600mm (HxWxD), and it weighs 74kg when empty. It can be used with both radiators and underfloor heating systems and is also compatible with solar thermal systems.
Thermaflow electric combi boilers
Warranty: 2 years
Output: 6kW, 9kW, 12kW
Thermaflow boilers are suitable for small to medium sized homes with one or two bathrooms. The range includes models such as the TH9-250U M3, TH9-330U MRK2, TH12-250U M3, and TH12-330U MRK2.
No flue is required, making them ideal for listed buildings and high-rise flats. The cylinder volumes vary from 150 litres to 450 litres, offering flexibility to suit different needs. The dimensions of the boilers are 900mm x 500mm x 300mm (HxWxD), and they weigh 85kg.
Mattira MAC15, Elnur
Warranty: 2 years
Output: 1-10kW, 11kW, 13kW, 15kW
Efficiency: 100%, 36.4% for 15kW
The Mattira MAC15 by Elnur offers options available in outputs ranging from 3kW to 15kW, making it suitable for larger properties. This fully modulating electric combi central heating boiler is wall-mountable and provides both heating and hot water. The dimensions of the boiler are 450mm x 600mm x 250mm (HxWxD).
The system incorporates a 50-litre water storage capacity. It is equipped with expansion vessels for both heating and hot water functions and can be seamlessly integrated with underfloor heating systems.
Any homeowner who is looking to install a new electric boiler in their home would be well advised to get quotes from several different qualified engineers.
Boiler Guide can put you in touch with 3 local engineers who can help. Simply fill out our 30-second form and you'll be matched with up to 3 certified boiler installers in your area. Compare their quotes to get the best price for your project. Our service is non-binding and has no hidden fees. Click below to begin.
The installation process of an electric combi boiler can vary depending on factors such as location, labour costs, boiler type, brand and model, and the inclusion of a built-in cylinder. However, here are some general steps that may be involved:
Site assessment by a heating engineer.
Selecting a boiler that meets your heating and hot water requirements.
Preparation of the installation site, which may involve removing the old boiler if necessary, and ensuring the necessary connections are in place.
Boiler installation in the designated location, including connecting it to the existing pipework and electrical supply as needed.
Testing the electric combi boiler to ensure its proper functioning, efficiency, and safety.
Commissioning the electric combi boiler. This entails setting it up to operate at the correct temperature and pressure for optimal performance.
Instructing on operating and maintaining the electric combi boiler, along with any relevant warranty information.
It’s important to note that the specific installation process may vary based on the individual circumstances and requirements of your installation. Consulting a professional heating engineer and following the manufacturer’s guidelines is recommended for a successful electric combi boiler installation.
Find electric combi boiler installers for your UK household
Before buying an electric boiler to be installed in your home, you'll want to first find boiler engineers in your area who will be able to quote you electric boiler prices. Getting prices from multiple certified engineers allows you to shop around and choose the best deal.
Spending just a few minutes getting free quotes from certified professionals can save you hundreds of pounds in the long run.
Our network of vetted and certified boiler engineers can help you get up to 3 free quotes to compare. It takes less than a minute to get started. This is the most convenient and time-saving way to ensure you're getting the best deal on a new boiler without any hassle or stress. Simply click the link below to get started.
How does an electric combi boiler work?
The electric combi boiler heats water whenever needed and provides both heating and hot water from a single unit. It operates using heat exchangers, which consist of two components: a primary heat exchanger responsible for central heating and a secondary plate heat exchanger dedicated to hot water production.
Is an electric combi boiler efficient?
Yes, electric combi boilers are frequently hailed as being up to 99%-100% energy efficient, making them highly regarded. Together with high efficiency, electric combi boilers boast other advantages.
How much electricity does an electric combi boiler use?
The electricity consumption of electric combination boilers depends on the boiler's output power and frequency of use. Generally, you can estimate that for every radiator in your home, you should have at least 1.5kW of power.
What is the best electric combi boiler for a large house?
It’s hard to answer this question as each house has its unique specifications and heating requirements. Consider going through electric combi boiler reviews, comparing products from various electric combi boiler companies or contacting local boiler installers to find a brand that fits your situation.
About the author
Nick has a wide range of experience writing about conventional and renewable heating solutions, and is always increasing his knowledge by researching any new heating technologies on the horizon.
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