Heating, accounts for about 55% of what you spend in a year on energy bills, so an efficient boiler makes a big difference.

Why are modern boilers so efficient?

Modern boilers are more efficient for several reasons, but their main advantage is that they are all condensing boilers. All well-maintained boilers burn their fuel very efficiently, but they inevitably lose some heat in the hot gases that escape up the flue. A condensing boiler has a larger heat exchanger, so it recovers more heat, sends cooler gases up the flue and is more efficient.

Combi, or not combi? That is the question…

If it is time to change your boiler, there are some considerations to make when you to decide which type of boiler is right for you..

Fuel type

If you have mains gas, a gas boiler is likely to be the cheapest heating option. Our average fuel prices as of April 2018 show gas to be the cheapest heating fuel per kWh, compared to oil, economy 7, LPG and house coal.

If you don’t have a gas supply to your home, it might be worth considering a form of low carbon heating such as a heat pump or biomass. With the renewable heat incentive these may be cheaper overall.

Alternatively you may want to get a gas connection to your home. The company that owns and operates the gas network in your area may be able to help with the cost of getting a new connection, and it may even be fully funded. Contact Energy Networks Association for further information.

Boiler type

Most old gas and oil boilers are regular boilers that have a separate hot water cylinder to store hot water, rather than providing it directly from the boiler. When you replace your boiler you can buy a new regular boiler, and keep your hot water cylinder, or buy a combi boiler that doesn’t need a cylinder.

A regular boiler is more efficient than a combi at producing hot water in the first place, but then some heat is lost from the hot water cylinder, so a combi may be more efficient overall. Which is better for you will depend on different things, including:

  • Your hot water usage
    Large families using lots of hot water are likely to be better off with a regular boiler, whereas smaller households using less may be better off with a combi boiler. l
  • Space in your home
    Combi boilers don’t need hot water cylinders, and therefore require less space in your home.

Our Accreditations