Best Electric Combi Boilers in 2024

Electric boilers have always been a popular choice for the estimated 2 million homes in the UK not connected to a gas supply. 

Extremely efficient and with a lower carbon footprint, they certainly have their unique advantages and with the government openly discussing a potential gas boiler ban, demand for them is predicted to continue. 

...but aren’t electric boilers expensive to run I hear you say? 

In this article, we will explore some of the most frequently asked questions and with an in-depth dive into the industry will present some of the best electric boilers currently on offer to the UK market. 

Factors we considered when selecting the best electric boilers 

Just like a traditional gas combi boiler, you want your electric boiler to act as a reliable source of hot water and heating, to have a relatively long life and ideally help save you energy and money on your heating bills. 

You also want the electric boiler manufacturer to offer a long warranty period so that in the event your boiler runs into trouble you will not have to worry about additional repair expenses. 

With these factors in mind, we analysed the following factors when putting together our list of the best electric boilers currently available in the UK: 

• Warranty period offered by the boiler manufacturer  

• The overall reputation of the boiler brand based on customer reviews 

• Reputation among boiler installers 

• Trustpilot reviews  

• Awards and accolades e.g. Which? Best Buy Awards

• Customer service performance 

• The price range of their boilers  

• Efficiency ratings

#1 Electric Heating Company (Best) 

As their name implies the electric heating company specialise in electric heating technology and has been innovating the industry for over 13 years. 

They make a wide range of electric heating products including radiators, water heaters and electric boilers. 

Their mainstay boiler range is the Comet electric combi boiler, which is suitable for use with central heating systems and for providing domestic hot water.

It also comes with a standard thermostat and digital interface, allowing you to set up a schedule and be smarter with your energy use. 

The Comet range offers an incredible 100% efficiency and is available in a variety of sizes and energy outputs including 9 kW, 12 kW or 14.4 kW.

The Comet range also utilises a stainless-steel heat exchanger, which is superior to the aluminium heat exchangers commonly used by budget boiler brands. 

• Warranty period: 2 years (10 years for the cylinder) 

• Price range: £2,000 - £2,600 

#2 Heatrae Sadia (2nd Best) 

Another big name dominating the electric boiler market is Heatrae Sadia, which is owned by the popular gas boiler brand Baxi heating, which also happens to own Potterton boilers. 

One of the main advantages of Heatrae Sadia is its well-established network of boiler installers and award-winning customer service centres. 

Their most popular electric boiler is called the Electromax, which provides both heating and hot water. Thanks to its innovative design (including a 190-litre cylinder) it also has the flow rate capacity to provide hot water for multiple outlets, making it ideal for busy households. 

The Electromax has a compact design, allowing it to be easily stored in the attic, garage, or airing cupboard. 

Offering a 99.8% efficiency rating and available in 6kW or 9Kw energy output, the Electromax offers eco-friendliness and can even be used for underfloor heating. 

• Warranty period: 2 years (10 years for the cylinder)

• Price range: £2,000

Read our new guide on gas boilers vs electric boilers, where we compare the pros and cons of each. 

#3 Elnur (3rd Best) 

Founded in 1973, Elnur first established itself as a leading name in the European electric heating market and today is leading the way in electric boiler technology. 

Their latest and most popular model is named the Mattira MAC15, a stylish-looking wall-mounted boiler, which also offers a practical solution for both instant hot water and heating. 

With 50 litres of water storage, the unit can provide a flow rate of 12 litres per minute. The digital display also offers ultimate user-friendliness and the ability to modulate the schedule, combine this with the 3-phase supply and it is an extremely energy-efficient electric boiler. 

The Mattira is available in twelve different energy outputs ranging from 3kW to 15 kW. 

• Warranty period: 2 years (5 years for the cylinder)

• Price range: £1,600 - £2,200 

#4 Thermaflow (4th Best)

Founded in 2004, Thermaflow is a relatively new boiler brand, but since then has established itself as one of the leading suppliers of electric combination boilers, and just like traditional gas boilers it provides both hot water on demand and heating water. 

One of the most impressive features of the Thermaflow brand is its commitment to energy efficiency. For instance, their High-Efficiency Electric Combination Boiler is designed to save money and their big claim is that “when used with cheaper off-peak tariffs such as the E10 Tariff or Economy 2000 Tariff, users can save up to 40% on their heating”. 

As an eco-conscious brand, they also offer a range of solar thermal combi boilers and enable you to reduce your bills further by tapping into biomass systems easily using their combi buffer vessels. 

The floor-standing Thermaflow high-efficiency combi boiler is available in 6 different energy outputs ranging from 10kW to 18 kW. 

• Warranty period: 1 year (25 years for the cylinder)

• Price range: £2,200 - £4,200

Advantages of electric combi boilers

Here are some of the major advantages of modern electric combi boilers: 

No need for a gas or oil supply 

Electric boilers are a viable solution for the estimated 20 million UK homes not connected to a gas line, for instance, those living in rural locations. All that is required is an electrical power supply and you are ready to go. 

A green heating alternative 

Unlike their rivals such as gas boilers and oil boilers, electric combi boilers do not generate heat because of combustion and so zero exhaust fumes are generated. This means your carbon footprint because of emissions can be reduced by opting for an electric boiler. 

100% efficiency 

Many electric combi boilers currently available have achieved 100% efficiency ratings. This means that the energy used is converted directly to heat and is not lost, unlike gas boilers, where some of the heat can be lost via the exhaust fumes. On the other hand, it is extremely unlikely you would see a gas boiler exceeding a 95% efficiency rating. 

Cheaper installation costs 

Electric boilers only require a power supply, unlike a gas boiler that requires the installation of a flue and a condensate pipe. As a result, boiler installation takes less time and requires less labour and materials, so is typically cheaper. 

No annual service required

Unlike boilers that generate heat from the combustion of fossil fuels, electric boilers do not so do not require such a consistent level of service. Therefore, you could expect to save money you might have spent if you had the likes of a gas or oil boiler installed. 

Carbon monoxide is not a risk 

Gas boilers and other combustible boilers generate the toxic by-product carbon monoxide, which can be deadly if a leak occurs, hence why a carbon monoxide detector is always advised. 

However, since electric boilers do not burn gas, there is no risk of a leak since do not produce any, to begin with. 

Compatible with green systems 

Many electric boilers easily allow you to power them using renewable energy sources, for example, additional linkage systems can allow you to connect your boiler to your solar panels so you can use this free energy source. There are also similar linkage systems for biomass, allowing you to power your boiler using wood heat. 

Install almost anywhere 

Since you do not need to install a flue (which needs to be fitted through the wall or roof) you have more flexibility as to where you can install an electric boiler. The majority also have small, compact designs and so you are unlikely to require much space. 

Quiet operation 

Electric boilers have no moving parts and so are relatively silent when running, unlike gas and oil boilers which are relatively noisy in comparison. 

Disadvantages of electric combi boilers  

Here are some of the most frequent complaints about electric boilers: 

Expensive to run 

The price of electricity is much more expensive than gas, so you can expect to have higher energy bills if you are relying on an electric boiler for your hot water and heating. This can be offset somewhat by making use of certain tariffs offered by energy providers and by linking it with renewable energy sources e.g. solar. 

Limited hot water 

Electric boilers do not generate as much heat and so can not heat water at the same rate a gas boiler can. For this reason, many have a hot water storage cylinder, yet still, their relative flow rates are limited, making less ideal for homes with a high hot water demand e.g. multiple bathrooms or larger homes. 

Are electric boilers expensive to run? 

Currently, there is little debate as to which type of fuel: gas or electric is cheaper – gas is by far cheaper than electric and this is the major reason why electric boilers are more expensive to operate than a gas combi boiler. 

For example, on average one unit of mains gas (in kWh) costs 4p/kWh, while one unit of electricity will cost around 15p/kWh. That means electricity is 3 times more expensive than gas to purchase. 

It is worth bearing in mind that the running costs are not the only costs you need to consider. There are the installation costs, with gas boilers typically costing more to install, especially if your property needs to be connected to a mains supply, which can end up costing several thousand pounds. 

You may be able to save money by opting for Economy 7 and Economy 10 tariffs with your energy supplier. These tariffs provide lower prices at off-peak times, usually, this means you will pay less for using electricity n the evenings vs during the day. 

Electric boilers vs. gas boilers 

The bottom line is that electric boilers are not advised for the average UK home, since they typically have higher running costs. However, they can be a convenient alternative for those living in rural locations and places with no natural gas supply. 

Why choose a gas boiler? 

• Although it is often repeated that electric boilers are eco-friendly since they do not use fossil fuels, you have got to consider how the electricity they use was originally generated. Even though the UK does generate electricity from renewables, the vast majority is still made using fossil fuels. 

• Natural gas is still much cheaper to purchase per unit (kWh) than electricity, so the running costs will be lower. 

• Gas boilers have a superior flow rate and are to heat water faster, hence why they perform much better in larger homes and those with multiple outlets. 

Why choose an electric boiler? 

• Electric boilers are extremely efficient, with many certified as 100% efficient, while gas boilers do not tend to exceed 95% efficiency. 

• They can be linked to your own home’s renewable energy stores e.g. solar and biomass helping you reduce your energy bills considerably. 

• Electric boilers themselves (although how the electricity was originally generated likely did) do not produce harmful carbon or toxic emissions. 

What size electric boiler do you need? 

Boiler size does not necessarily mean the dimensions of the boiler, but the heating output or power of the boiler. An electric boiler’s power output is measured in kilowatts per hour (kW) and the higher it is the more water outlets it can generally provide water to. 

Across the board, electric boilers are less powerful than their gas rivals, for comparison the average gas boiler is measured at between 25 to 35 kW, while the average electric boiler is 12 to 15 kW. 

In general, installers will determine how many radiators you need to calculate what size of electric boiler you need. 1.5 kW of power per radiator is used to come to an estimation, but this varies tremendously based on the size of your property, the pressure of your mains water supply and so on.  

Final thoughts on Electric Boilers 

Electric combi boilers are less ideal in many ways when you start to compare them to gas combi boilers. 

Probably most important for most homeowners and families is that they are more expensive to run. Next is the fact that they are usually not suitable for larger homes, as they fail to provide adequate hot water flow to satisfy multiple outlets simultaneously. 

Overall, gas combi boilers win out when it comes to running costs and practicality. However, for those with no gas supply, or those who can hook it up to a renewable power source e.g. solar, an electric boiler may be a suitable alternative. 

Looking for the best deal on a new boiler? 

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