Back Advantages and Disadvantages of a Combi-Boiler

A combination boiler owes its name to the fact this variety of boiler functions as a duel hot water and central heating devise. Since this variety of boiler draws its water directly from the mains, no hot or cold water cylinder or storage tank is required. In this post we discuss the advantages and disadvantages of a combi-boiler. We hope by the time you have finished reading this post you will know whether this variety of boiler is suitable or not for your specific needs.

Let’s start by examining the disadvantages of the combi-boiler:

Disadvantage 1: Struggles to meet high demand for water

Yes you heard me correct! Since a combi-boiler draws all its water supply directly from the mains, this variety of boiler will struggle to meet a high demand for water. For instance, if three people simultaneously turn on taps in different rooms, the water pressure will dramatically reduce. This is because a combi-boiler does not have the benefit of a back-up water tank to meet this level of demand. Therefore larger properties with many inhabitants may be better suited to a traditional boiler that also comes with a water tank.

Disadvantage 2: Overly complex set-up

Combi-boilers require complex chips and electronic devises in order to operate. If things go wrong the bill for a combi-boiler’s repair is typically more expensive than for more traditional boilers. Combi-boilers also tend to take more time to fix. This in turn pushes up labour costs, since most boiler engineers work on an hourly rate.

Disadvantage 3: Slower water rate

Since a combi-boiler draws its water directly from the mains and not a water tank, you may find a combi-boiler requires more time than a traditional boiler in order to fill a bath.

Disadvantage 4: If a combi-boiler breaks down, you lose hot water and central heating

A combi-boiler powers your central heating and hot water. Therefore if you combi-boiler malfunctions, you won’t be able to access hot water or central heating. Traditional boilers only power you central heating. A separate boiler powers you hot water. Therefore with traditional boilers you’re only likely to suffer hot water or central heating outages at different times.

Now let’s explore the advantages of combi-boilers:

Advantage 1: Compact size

Combi-boilers are very small when compared to a conventional boiler. There is no need to store hot water as is case with conventional boiler. Combi-boilers eliminate the need for a large hot water cylinder commonly found in airing cupboards. In contrast combi-boilers require only a small space in your kitchen or upstairs airing cupboard.

Frees up roof or loft space as no need for cold water storage unit. This is because combi-boilers receive their supply of cold water directly from the mains. A lack of water storage units also gives combi-boilers the edge when it comes to installation. No water storage unit translates into less work and hassle when it comes to installation. A lack of a cold water unit also reduces the risk of pipes freezing during the British winter time.


Advantage 2: Excellent efficiency

Highly efficient - in fact combi-boilers are up to 90%+ efficient. Heating your home is therefore more affordable when compared to conventional boilers.

Advantage 3: Fast access to hot water/central heating

No need to wait for water to be heated. Combi-boilers heat water according to demand. Therefore combi-boilers are very convenient if many people are queuing to use the same bathroom. Since hot water is provided ‘according to demand’ there is no risk of water running out as is the case with a conventional boiler.

Advantage 4: Saves you money!

Since water is heated in small quantities, you save money compared to traditional boilers which heat vast quantities of water even if you simply want to wash your hands! This is because conventional boilers require you to heat up an entire cylinder full of water, even if you just want to wash the dishes! Combi-boilers therefore have a smaller carbon-footprint when compared to conventional boiler.


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