Boilers and central heating

If your boiler is more than 10 years old, it is likely that replacing it could make a huge difference to your bills and comfort levels. Modern combi boilers not only take up less space (not requiring a water tank), but are also much more efficient- recovering more heat through the use of a larger heat exchanger.


Newer combi boilers do not have a hot water tank, so may require spreading out hot water use if you have a few people wanting to take baths or showers at similar times, but are much more efficient. If planning major renovations, you may want to consider other forms of central heating such as combined heat and power (CHP) or biomass, or the addition of solar hot water.

Alternatively if you want a hot water tank, you should still opt for one of the newer types of condensing boilers, which achieve higher efficiency by using waste heat in flue gases to pre-heat cold water entering the boiler. This is also a consideration if you are planning to instal solar thermal panels.

Effective use of your boiler also requires an understanding of your central heating controls. When having the boiler replaced, or looking at your current system, you should also consider the addition of thermostatic radiator valves to ensure that you are only heating the rooms which you are using. You may also want to look at more sophisiticated heating controls (link to page).

Geek says

If you install a combi boiler and take out your hot water tank, this will make it difficult and expensive to install solar hot water panels on the roof at a later date. To get the most out of your solar thermal panels (quite different from photovoltaics) you will need a large hot water tank to store water heated during the day so that you still have hot water in the evening and next morning.

Local experiences

Judith had an ageing combi-boiler which had needed repair twice in recent years so was due replacement.  She met Nick Atkinson of Aqueco  when he had a stall demonstrating water saving at the Wolvercote mid-summer festival- he had done some work for others in the village, as well as other LCON members.  He installed a condensing boiler, solving a pipework issue along the way. She feels that Aqueco lives up to its claim of environmental responsibility and can do a much bigger range of jobs than she has needed.  She says: “Nick’s definitely  a plumber who sees the bigger environmental picture – he’s since topped up my central heating by installing a radiator on the landing, at the same time putting insulation under the floorboards while they were up”.

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