Although a boiler can seem like a huge expense at the time you buy it, if you’re replacing a boiler that is over 15 years old you’ll probably save money in the long term. If you update your boiler from a G-rated to an A-rated condensing boiler, you could save up to £215 a year and reduce your carbon emissions by 15-30%.

So which boiler should I choose?

There are a lot of options to choose from, but some of them will depend on your family’s needs. All boilers must be condensing boilers by law, but there are three types you can choose from:

Open vent boilers

Open vent boilers are regular boilers that need a separate hot water cylinder. You’ll probably need space in your loft for an expansion tank. If you have more than two bathrooms, an open vent boiler is probably best for you as it can store lots of heated water for you when you need it. If you’ve got low water pressure they’re also very good. If you have or are considering solar thermal panels or underfloor heating, open vent boilers are compatible with them.

Combi boilers

Combi boilers heat water straight from the mains on demand, so you never have to wait for the hot water to heat up. If you’re a family of up to 5 and you don’t have more than two bathrooms, you can save money with a combi boiler. You’ll only pay for what you use, and the water is delivered at mains pressure. The downside to combi boilers is that they’re not compatible with solar thermal panels.

System boilers

System boilers also operate with stored water, in the form of a mains pressure hot water cylinder or a low-pressure tank-fed cylinder. It’s called a system boiler because most of the parts of the heating and hot water system are built into it. Usually, they’re more efficient and they don’t take up as much space, as you don’t need an expansion tank in the loft.

You can use system boilers with solar thermal panels and underfloor heating.

Things to think about and costs

The cost of a boiler will depend on its SEDBUK (Seasonal Efficiency of Domestic Boilers in the UK) rating. You want to get an A-rated one, as this is the most efficient, turning more than 90% of fuel into useable energy. Of course, an A-rated boiler will be more expensive than the lower rated ones, but you’ll waste money in the long run with a lower rated boiler as it won’t turn as much fuel into energy.

Make sure you find a reputable gas fitter

Gas engineers must be on the Gas Safe Register to legally install, repair and service boilers. Make sure you check their ID card when they come to your property and run this against the Gas Safe website.

Shop around – don’t go with the first price you’re quoted for as you can probably get it cheaper. Get a range of quotes so you can see what’s out there.