Heating|April 12, 2012 12:29 pm

What is an electric boiler?

People often get confused between an electric boiler and other types of electric central heating systems. So the aim of this blog is to educate you in the different types of electric heating systems.

Let’s start with electric central heating boilers

These boilers are often wall mounted units. The most efficient models have the ability to heat water to up around 70c, with an adjustable temperature control on the front.

These boilers are ideal for smaller properties where installing a flue isn’t an option. Electric boilers don’t require a flue, nor emit any toxic gasses. Another huge plus is that they are very low maintenance, so repair costs are low.

A typical electric central heating boiler will look like this:


Often customers call and say they have an ‘electric boiler’ when what they actually have is a Direct (powered by electricity via immersion elements) hot water cylinder. On the odd occasion they might be asking for us to come and look at an ‘electric boiler’ but more often than not, it will just be the cylinder. This can be easily determined by asking them a couple of questions :-

1. Are they talking about the hot water cylinder usually located in some sort of airing cupboard, or are they talking about a small electric unit which feeds the radiators in the property?

2. Do they have storage heaters? If they do it is likely they are talking about the hot water cylinder as storage heaters work independently rather than being fed from a central boiler.

3. Does the unit they refer to have any make and model on it (This will normally indicate exactly what we’re looking at!). There is one unit I know of on the market that is both a direct fed cylinder and an electric boiler which can feed radiators (Heatrae Sadia Electromax)

An electric immersion heater is an rod/coiled shaped device placed inside of a hot water tank, which is used to maintain the temperature of the water. The following images demonstrate different types of immersion heater configurations.

The immersion heater within a hot water tank will look like this:

But what other types of electric heating are there?

One of the cheapest ways to electrically heat your home is by going on an Economy 7 tariff and using storage heaters. These are heaters that “charge” throughout the night, storing heat that’ll be released through the following day to maintain the temperature of the property.

Storage heating is often seen as inadequate in the Winter months, as when the heat runs out they need to be re-charged – and you’re without heating. A gas or electric central heating system will supply continual heat to the property.

Dimplex Storage Heater

Storage Heater

Underfloor heating is another option. Having either dry underfloor heating – which doesn’t use heated water – or wet underfloor  heating (which does), you can easily control the ambient temperature of a room to cost effectively maintain comfort.

A wet underfloor system, which heated water runs through, will in most cases be heated by an electric boiler (see above). For a super efficient heating system, you can even install solar PV panels to help power the electric boiler. Giving you a more sustainable and cheaper to run central heating system.

A slightly less common boiler is the Heatrae Sadia Electromax, which I mentioned before. This boiler combines both an internal tank and the element – into one self-contained unit. You can read more about it here.


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