• Katie Heirene

Switching to a combi boiler? Here's what you need to consider...

Nowadays over half of all new domestic boilers installed are combi boilers. Their space, energy and cost saving qualities have made them a firm favourite amongst medium sized family homes. Scott and Arran have moved a lot of customers across from their old central heating systems to the combi. But if this is something you are thinking about then there are some important things that you need to consider first to ensure that this system is right for you…

What is a combi boiler?

A combi boiler does exactly what is says on the tin - it is both a central heating boiler and a hot water heater in one compact unit, therefore eradicating the need for a hot water cylinder! This means hot water can be delivered instantaneously through your taps and shower at mains pressure, without the need for a hot water pump.

How does this compare to other boilers?

Alternatives to combi boilers; which are more commonly used in larger properties with more than two bathrooms; are heat only or system boilers used in conjunction with a hot water cylinder. These boilers generate hot water that is pumped around the radiators to warm your home and through the coil in your hot water cylinder to indirectly warm the water in the tank - where it is then stored until hot water is required.

Pro’s of a combi heating system:

  • There is an instant and unlimited hot water supply

  • More space efficient - no space is required for a hot water cylinder or storage tanks

  • More energy efficient - hot water is generated on demand, not heated and stored in a tank all day

  • Usually cheaper to install as less components, pipework and labour are required

Drawbacks of a combi heating system:

  • There is no back up supply of hot water - if the boiler breaks down there is no heating or hot water. Whereas with a heat only or system boiler and cylinder the hot water can still be warmed by an immersion heater.

  • Unfortunately this system is not suitable for a house with more than two bathrooms (this doesn’t include a stand alone W/C) because there is not enough pressure in the system to supply them all via the mains - and Power Shower’s are NOT compatible! (However a way around this is to install an electric shower that heats the water separately - pressure and energy efficiency will be less though.)

  • There can be a slight delay when you turn the hot water on as the boiler has to fire up to heat the water - although this is minimal


There are some fantastic energy efficient boilers on the market to suit all systems. However if you don’t have more than two bathrooms and don’t plan to extend your property, then providing you are not overly concerned about having a back-up hot water supply a combi seems to be the most efficient all round. If you have a larger property with more than two bathrooms or love your power showers then a system boiler is generally your best option as these already contain the pressure vessel and pump neatly inside the boiler. Also if you are inclined to leave your heating off for prolonged periods of time but still need access to hot water then again this is the best option for you.

Either way Scott can install both systems whether they are gas, oil or LPG powered so if you are thinking of installing a new boiler get in touch for a FREE quote and some advice on what the best option maybe for you!

#Combiboilers #centralheatingengineersnantwich #Worcestorboilers #systemboilers #heatonlyboilers

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Address: Springfield, Wrenbury, near Nantwich, Cheshire, Cw5 8HF


Company number: 9637302


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