• Nicholas Hall

How to tell the difference between a Combi Boiler and a Conventional Boiler?

Spot the difference….

The main, or most noticeable difference between a Combi and a Conventional system is the lack of a storage tank in the Combi system. A Combination system combines both the water heater and central heating system into one, hence the name. The system requires no additional storage tanks for either hot or cold water. This system also has the added point that it will provide hot water as soon as you run the hot tap.


A Conventional boiler requires additional tanks, one for cold water that would feed all non-drinking cold water taps in the house as well as feeding water to the hot water cylinder and a second tank that stores hot water and feeds the heating system.

So now you have a basic understanding of what is involved in each system which one would be best for your home?


In terms of energy efficiency, the Combi system wins every time, you could save money on your energy bills by switching to a Combi system if you don’t have one in place currently. It’s also worth noting that these systems can often be cheaper to install as they are less labour intensive and involve fewer materials than a Conventional system.


One area where the Conventional boiler wins a point over a Combi boiler is when it comes to poor water pressure, a Combination boiler will not function properly if the mains pressure feeding the system is low. Due to the presence of water tanks, a conventional system does not share this problem. It also has the added advantage of still having a supply of water if the boiler breaks down thanks to the hot water storage tank.


Overall, a Combi boiler is likely to be better suited to most homes, it is more energy-efficient, you have hot water on tap (quite literally) rather than waiting for a storage tank to be heated and they often cost less to install in the first place. However, it’s always best to do your research and speak to a gas safe engineer who will be able to guide you In the right direction of what is best for your home and lifestyle.


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