Boilers can save energy and money
Have my neighbours done this?
What is it?
Boilers heat the water in central heating systems
What will it save me?
Modern boilers use around 25% less fuel than old ones
How do I get it?
A boiler needs to be fitted by a specialist contractor
What does it cost?
Gas boilers cost around £2,000 installed (2013) others may be more
What are the technical details?
Central heating boilers need to be replaced periodically mainly due to failure or persistent problems. The life expectancy is probably around 15-20 years depending on its design and service history. Although some can last longer, they tend to lose efficiency each year until they cost more in fuel than the boiler is worth.
a. Gas and oil boilers are graded depending on their efficiency. Those in Band A are the most efficient, operating at around 90% whereas a 20 year old boiler may be in band F or G and operating at less than 65%. The difference in efficiency represents how much less fuel you use. Reducing heating fuel costs by 25-30% is normal when an old inefficient boiler is replaced with a high efficiency version.
The Building Regulations require replacement boilers to be in an efficiency band A or B. This means a high efficiency condensing boiler, where “condensing” refers to the fact that the flue gases condense inside the boiler to achieve its high efficiency.
There are generally 2 types of boiler, a standard boiler or a combination boiler. The standard (conventional) boiler can provide hot water if it's connected to a hot water cylinder whereas a combi (combination) boiler contains an instantaneous water heater as well as a boiler and provides constant hot water separately from heating radiators.
All new gas and oil boilers and gas air heaters are high efficiency regardless of the type although they will only stay efficient if connected to an effectively controlled heating system and are serviced regularly.
b. Solid fuel free standing boilers could be replaced with a biomass boiler. Modern biomass boilers are clean burning, highly efficient and can have automatic fuel feed and temperature controls. Like a solid fuel boiler, you will need to store the fuel but they produce very little ash and need emptying infrequently.
There are different types of wood fuel they can burn including logs, wood chip or manufactured pellets and can even include closed stoves with a boiler fitted inside to heat radiators.
c. Electric boilers come in different forms with a direct boiler working in a similar way to an electric shower with a large capacity heating element heating water as it passes through a pipe to the radiator system. They tend to be easy to install, take up little space and don't need a flue, but are expensive to run using on-peak electricity. It may be better to consider the alternative of a heat pump.
All boilers need to be installed by specialist heating engineers who are approved to verify that installations are safe and comply with Building Regulations. Gas boilers require GasSafe approved engineers; oil boilers require OFTEC engineers, solid fuel and biomass need HETAS approval and electrical boilers require IEE engineers.