Electric Boilers: Everything You Need To Know

How do electric boilers work?

Gas combi boilers work via a burner. This burner uses gas to create a flame, which in turn heats cold water as it passes through a pipe. This heated water is then sent to both your radiators and hot water appliances. As electric boilers are powered entirely by electricity, and there is no gas supply, they cannot work in the same way.

Instead, most gas boilers utilise an immersion heater (or element) to heat a tank of stored water, in a similar way that a hot water cylinder does. The water in an electric boiler is usually heated to a much higher temperature than a cylinder however; as it needs to be hot enough to heat your home, not just wash the dishes.

This stored water is then sent around your heating system, or to your hot water appliances, when needed.

Electric combi boilers, such as the Fischer Electric Boiler, include two separate tanks of hot water – one for heating, one for hot water. They will be heated to different temperatures, as your heating system requires water at a much higher temperature than taps, showers etc.

How efficient are electric boilers?

The simple answer is 100% efficient. But what does that mean?

All electrical heating appliances are 100% efficient, in that they convert all of the energy they consume into heat. Gas boilers, and other alternatives, are not, and never will be, 100% efficient. On average, the efficiency of a gas boiler will be in the high ninety-percent range. For gas boilers over 25 years old, the efficiency may be as low as 60%.

How long do electric boilers last?

Gas Boiler Ban 2025

Although gas boilers have an expected life span of around 10-15 years (depending on the model), there is no set lifespan on the Fischer electric boiler. This may differ for other brands of electric boiler; however, from our research no lifespan is specified.

You also must bear in mind that the installation of gas boilers has been banned in all new properties from 2025. The government are also looking to ban the installation of gas boilers altogether by 2035.

Our boilers are manufactured using the same technology that has been used to develop commercial scale electric boilers for many years. They are extremely robust, and built with only the highest quality components. With a wireless thermostat supplied as standard, you can be in complete control of your heating from anywhere in your home.

How often should electric boilers be serviced?

Although we cannot speak for other boilers, the Fischer electric boiler doesn’t require a scheduled yearly service. Instead, we recommend that the boiler be checked by a qualified plumber every 5 years.

With a gas boiler, you are required to service the boiler every 12 months to maintain your warranty. As the gas used to power gas boilers is a potentially dangerous gas, you must also have the boiler serviced yearly for safety reasons.

Electric boilers rely entirely on electricity, thus no gas safety checks are required.

How do electric boilers compare to gas?

There are some similarities between gas and electric boilers, but there are also many differences.


Gas boilers require yearly servicing in order to maintain your warranty and prevent an unexpected gas leak. Most electric boilers do not require a scheduled yearly service, and instead you are advised to carry out a general check over periodically.

For example, it is recommended that the Fischer electric boiler be checked over by a qualified plumber every 5 years.


Gas boilers are never 100% efficient. The average gas boiler will be somewhere upwards of 95% efficient, with the maximum being around 98%. All electric boilers are 100% efficient, converting one hundred percent of the electricity they use into heat.

These figures refer to efficiency at the point of use, so you could be losing more efficiency through your pipework and radiators.


Most gas boilers come with a central thermostat, which is usually wall mounted and installed in the hallway. This means that if you set a temperature on the thermostat in the hallway, only that one room will ever reach your set temperature, as that is where the temperature reading is taken. Most of us do not sit around in the hallway, so it’s slightly pointless.

With the Fischer electric boiler, we supply a wireless thermostat, so you can control your boiler from anywhere in the home. This also means that the boiler will not switch off until that room is at the right temperature. You can position this in your lounge, where you may spend most of your time, or any other room in your property for an improved level of control.

Are electric boilers cost effective?

It’s no secret that a unit of electricity costs more than a unit of gas. However, you have to factor in the ongoing maintenance associated with a gas boiler. And although fuel cost impacts every single one of us, so does the environmental cost of burning fossil fuels.

According to a recent study, gas boilers emit “twice as much CO2 as all power stations in the UK combined.”

What are the best electric boilers?

Best Electric Boilers

By using a nickel-iron-chromium alloy, with the addition of molybdenum, copper and titanium – Fischer electric boilers provide high levels of resistance to a large number of corrosive environments.

Due to its low emissions, the Fischer Electric Boiler does not need a combustion tank or chimney.

The boiler is equipped with two independent tanks, insulated with 10mm of icolem. One tank is for hot water, with a capacity of 100L, manufactured in AISI316L stainless steel, designed to work up to 70c. There is also an in-built expansion vessel.

Due to the volume of water contained in the tank, you can remove your existing system boiler and hot water cylinder, and simply replace them with one single Fischer Electric Boiler.

The second tank is carbon steel and is part of a closed circuit for heating, designed to work up to 90c, also with its own expansion vessel.

Our boilers are also available as heat only, allowing you to install either an Aquafficient or Aquafficient Eco+ for your hot water supply.

Much like our combi (duo) boilers, our heating only boiler doesn’t require a scheduled yearly service, and both options come with a 10-year warranty for complete peace of mind.

Manufactured as standard with a wireless thermostat, you can be in full control of your heating from anywhere within your home.

By keeping your existing radiators, we can quickly and efficiently replace your existing boiler, allowing a seamless, mess-free change over.