When the time comes to replace the boiler, it’s easy to fall into the trap of choosing the cheapest option that works — or the first one you come across — just to keep the heating and hot water flowing.

However, with a little thought you can reap the benefits of choosing the right boiler; from lower energy bills to maintaining the potential for future home improvements. We know that getting great value for money is a must, but you shouldn’t compromise on quality, energy efficiency or capacity.

Following these straightforward steps will help you find the right boiler that fits your needs as well as your budget.

Research your options

Start by doing a little research; if you’re reading this, you’re on the right track. Dig a little deeper and learn more about the different types available to you. Here’s a quick list:

Combi (or combination) boilers

These are the most popular type of boilers sold in the UK, as they provide instant hot water without the use of tanks or cylinders. They’re relatively compact and have the added bonus of supplying unlimited heat and hot water to your taps and radiators, whenever you need it. On the downside, if multiple taps are used simultaneously, water pressure may suffer. Combis are great for smaller households that don’t need to use various sources of hot water at the same time.

Conventional boilers

Also known as regular or open vent boilers, these include a cylinder and a tank to accommodate all your water heating needs. Although they do allow you to use multiple taps simultaneously without reducing water pressure, once the hot water supply has been used up, you’ll have to wait for it to reheat. Due to their size, they’re not the best option for homes with extremely limited space.

System boilers

Commonly referred to as sealed system boilers, these heat water from the expansion tank and store the hot water in a cylinder. They’re smaller than conventional boilers, but still, have the downside of a limited hot water supply. However, they do allow you to use multiple taps at the same time, making them ideal for big families.

Condensing boilers

Combi, conventional and system boilers are also available as condensing boilers. These have the added feature of being able to capture and reuse some of the heat it puts out. They’re very energy-efficient with up to a 25% reduction in carbon dioxide emissions and lower energy bills. However, they are generally more expensive than traditional boilers, although the energy savings will eventually offset this upfront cost.

Combi vs conventional vs system boilers: what's the difference?

Get in touch with the manufacturer

Once you’ve found the right boiler, contact the manufacturer directly to get a list of local installers. Get a few quotes in writing and have an in-depth discussion with each installer to go over your heating needs. A few things to bring up include:

  • How many bathrooms you have in your home
  • How much hot water you typically use
  • Whether you have double-glazed windows
  • How well insulated your home is

This should help you and the installer decide what capacity your boiler should ideally be.

Learn all you can about the heating engineer prior to installation

After you’ve taken some time to chat with your potential installer, you should have a good feel for their overall knowledge and expertise. However, since it’s such an important job, you’ll need a little more than that to put your mind at ease. Check to make sure your installer is Gas Safe (previously run by Corgi) registered and ask to see their credentials.

With our maintenance and support plans, you'll get an annual service of your boiler and ongoing maintenance hints and tips, helping you to keep your boiler running.

About the author

Ian Palmer-Smith

Ian is the Supplier and Heating Service Director at Domestic & General. He leads the operational delivery for ScottishPower, as well as managing operational relationships with heating manufacturers and our service network in the UK and Éire.

He’s an advocate for the prevention of carbon monoxide (CO) poisoning, becoming a member of the All-Party Parliamentary Carbon Monoxide Group (APPCOG) in 2020. He's worked in the heating sector for over 37 years and regularly contributes to our articles.

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