Combi Boilers – Pros & Cons of Gas Combi Condensing Boilers

By Rebecca Fox on January 30, 2015

Combi boilers, also known as combination boilers, are highly efficient condensing boilers that take up very little space within the home. They are now used in the majority of new boiler installations in the UK because of their size and the fact that they are highly efficient.

Gas Combi Condensing BoilerThe combi boiler is different from other types of boiler in that the need to store hot water is eliminated, making a hot water cylinder within an airing cupboard unnecessary.

The name ‘combi’ refers to the fact that these boilers work not only as an extremely efficient water heater but also as a central heating unit as well.

Why choose a combi boiler?

Firstly there is protection from sudden changes of water temperature while you are in the shower due to thermostat controls. Most combination boilers have these controls and they often come as standard.

Secondly, if you don’t have much roof space for the installation of a different type of boiler or you want to use the loft space as a room or in some other manner then a combi boiler is probably the best choice for you.

Thirdly, if you are upgrading the boiler on an existing system then this type of boiler is easily the most efficient type around. Lastly, it may not be convenient for you to have to wait for water to heat up if there are a large number of people in the home – a combi boiler heats water on demand.

Advantages of a combi boiler

Normally with a combi boiler there is a simple compact unit in the kitchen or utility room or occasionally in an airing cupboard. Space is saved due to the lack of a hot water storage unit, a cold water storage unit and other components that usually make up a normal heating system.

The major advantages of this type of boiler are the monetary savings seen on the cost of hot water, the fact that you get water out of the taps or shower at the same pressure as if it was from the mains and the fact that there are no tanks being placed in the roofing and less pipe work to install. This in turn means installation is faster and not as difficult thus reducing initial costs as well.

As combis are so common boiler service costs should be relatively low whilst parts and engineers easy to find.

Disadvantages of a combi boiler

There is only one real disadvantage to these boilers and that is that in order to get hot water on demand you need an adequate supply of cold water. This means that if a large number of taps or showers are using hot water at the same time then the flow to each one is reduced depending on the amount of power your combi boiler has. Consequently, if the mains water supply is not adequate or you have sudden pressure decreases then this type of boiler is not suitable for your situation. For this reason you might also want to check that the type of shower you have is compatible with a combi boiler as some pump assisted or multi-jet showers might not be suitable.

There are a number of advantages to the combi boiler such as hot water on demand and cold water coming from the water main thus eliminating the need for a cold water tank and a hot water cylinder. They are also highly efficient and can often generate significant savings on gas bills.

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