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Tuesday, 31st January 2012
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Blog postPlumbing & heating

What is a combi boiler?

boilerTo kick start this week’s worth of PGS blogging, I’m going to run a mini-series of blog entries to tackle the big question of what boiler is right for you. Rather than go into what manufacturer is best, I’m going to outline the different types of boiler, when they’re used and of course, how efficient they are.

There are many different types of boiler available, however the most common gas boilers are combination (often referred to as combi), regular and system. Each of them differ in configuration, so it’s important to know what kind of boiler you will need before you purchase anything. This blog post will focus on combi boilers and will outline who they are suited to, how they work and whether it’s the right boiler for your property.

What is a combi boiler?

Combi boilers are the most energy efficient gas boilers available. As they are also the cheapest to install, they are the most common boiler found in domestic applications. They drastically vary in price and quality, with low quality combination boilers starting at around £400, to the most advanced and high end of devices costing thousands. Most average boilers cost around £700 – £1400 and a combination boiler priced at around this will, in most cases, provide many years of reliable operation and will cost less to service due to the parts being more widely available.

So how does a combination boiler work?

A combi boiler uses an internal heat exchanger to heat the water passing through the boiler direct from the mains supply, and can provide both hot water to taps and also heat a central heating system. As both CH (Central Heating) and DHW (Domestic Hot Water) are supplied from this one singular space-saving device, there is the huge advantage of not needing a hot water storage tank. Combination boilers can often control the temperature of the hot water and the central heating individually, and as the water comes directly from the mains supply rather than a storage tank, a much higher water pressure level can be achieved.

How can I tell if I need one?

The main incentive people have to get a combi boiler is to save money on installation costs and also save space. You won’t need a hot water cylinder in your loft or airing cupboard and the combi boiler can in most cases simply be hung from the wall. Some combination boilers are so small that they can even be installed within a standard sized kitchen cupboard. As the water is only heated when you need it, it also saves money on fuel bills. Combis are the most common choice for the majority of new households, despite this however, there is on particular negative aspects of a combi - As the water is heated on-demand, rather than stored in a tank and constantly kept warm, there is often a delay in the hot water arriving at the tap. Although, once you get involved in the higher end combination boilers, this delay is actually only a matter of seconds.

What types of properties is it for?

A combination boiler can be used in nearly all domestic properties. Large properties with more than one bathroom and where the hot water demand is very high, might benefit from a regular or system boiler, however a few high end combination boilers can cope with this extra demand but can be very expensive.

Overall the combination boiler is a very safe and reliable choice for cost efficient water heating, and if you have a small to medium sized property then this is the natural choice. Installation is quick and easy in comparison to other boilers and the energy saved from only heating the water when needed is vast. The manufacturers to look out for are Vaillant, Worcester-Bosch, Baxi, Potterton, Ideal, Glow Worm, Ariston, Remeha, Viessmann and Vokera.

If you have any queries about whether a combination combi can be fitted into your property, want to purchase a boiler or wish to arrange an installation, then that's what we're here for! Contact PGS Services today!

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