How to upgrade to a combi boiler

Combi boilers are one of the most popular heating solutions in the UK. They offer many advantages over traditional systems, such as saving energy, money, and space. Many homeowners ask, "Should I swap from a system or heat-only boiler to a combi boiler?"

Here, we lay out the facts and share everything you need to know before deciding whether upgrading to a combi boiler is the right choice for you and your home.

What's the process for changing to a combi boiler?

Changing your heating system over to a combi boiler involves specialised work and can cause some temporary upheaval. As it’s a legal requirement that only qualified professionals work on gas appliances, you must employ a Gas Safe registered engineer for the job. A poorly installed boiler can be extremely dangerous and will perform less efficiently.

The exact process depends on your current system. If you are moving from a conventional boiler with a water tank in the loft and a cylinder in an airing cupboard, the job will involve removing these items and running new pipework. In some cases, this may involve lifting floorboards. 

You may also decide to have new radiators fitted at the same time, but this is a personal preference. For more expert advice on the process, you’re always welcome to talk to our team.

How long does it take to install a combi boiler?

The time it takes to install a combi boiler can depend on a few different factors:

• Whether you already have a boiler

• What fuel you are using

• Whether you are relocating your boiler

• What type of boiler you are having installed

• Whether you are changing the type of boiler, and what type you are changing to and from

• Any complexities due to the type of home, existing water supply, etc.

As a general rule, we would say that installing a combi boiler takes one to four days to complete. That is taking into account any problems your current heating system could pose. To get a more accurate quote on how long installing a combi boiler will take, use our Boiler Finder or talk to our team. 

When should I change to a combi boiler?

You should upgrade to a combi boiler if your current boiler is coming up to 15 years old. Combi boilers can be up to 90% more efficient than other models, so if your boiler is old you will definitely reap the benefits of a new boiler. 

If you're planning an upcoming house renovation, consider changing to a combi boiler. If you need pipework added or re-done, installing a combi boiler could become quite messyas it may involve fitting pipes under the flooring. So, it’s often a good idea to install your combi boiler as part of your house renovation to minimise any disruption. 

So, is it worth changing to a combi boiler?

Changing to a combi boiler can have many advantages, but they’re not for everyone. A combi boiler may not be the best choice for a very large property with numerous bathrooms, for example, as it could make using hot water outlets simultaneously challenging. It’s important to check that a combi boiler will be right for the size of your property before deciding to make the switch. 

For many people, one of the most attractive benefits of combi models is that they only heat water as and when they need it, helping to save money on energy bills. Combi boilers also take up much less space compared to traditional heating systems, as there is no need for an extra water tank or storage cylinder, which is why it’s a great choice for a smaller property.

 Our helpful, combi boiler guide outlines further advantages.

Combi boilers are also compatible with Ideal Heating’s Halo thermostats, which are simple and easy to use. They are energy efficient, giving you full control over your home's thermal comfort whilst reducing your bills and carbon footprint. Read our guide for more information on combi boiler thermostats. 

Now that you know everything you need to know about upgrading to a combi boiler, you might be interested in this handy link to find local and national installers, including Max Accredited Installers who have undergone training with Ideal Heating.

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