Combi boilers

Combi boiler

Combi boilers explained - 1:15

There seems to be a problem playing this YouTube video

To view please try one of the following options:

  • Check your YouTube access
  • Or go direct to YouTube

Combi, or combination boilers, are the UK’s most popular type of boiler.

They provide heat to your radiators, plus limitless hot water on demand by heating water directly from your mains supply.

This makes them an economical solution for many households, as they only heat the water you use.

There’s no need to store water, so you don’t need room in your loft for a cold water tank, or space for a hot water cylinder.

This often makes them great for smaller homes where space is limited.

If you’re using more than one tap at the same time, the flow of hot water can be reduced, meaning they’re not always suitable for bigger homes with several bathrooms.

If you think a combi boiler is the right option for you, book an appointment with one of our expert Heating Advisers who can assess your heating needs and give you a quote.

If you’re happy with our quote, they can arrange an installation date that’s convenient for you.

Visit our website to find out more about boilers.

Or take a look at our other videos to find out more.

Combi boilers explained

  • Combi boilers are the UK’s most popular type of boiler.
  • Hot water for your taps and central heating system is supplied directly from the boiler unit.
  • Ideal for smaller homes and homes with one bathroom.


  • Provides limitless hot water on demand.
  • Can be an economical option, as combi boilers only heat the water you use.
  • A great space-saving solution with no need for a separate cold water tank or hot water cylinder.
  • Installation may be quicker as there are fewer parts in a combi central heating system.


  • Depending on your mains water pressure, the flow of hot water could be reduced if you’re using more than one tap at the same time.
  • Water can sometimes take a few seconds to heat up.

More useful information

We have offers and discounts available for a limited time only.

Find out how much you could save with a new boiler.

We have a range of boilers to suit your home.

Worcester Bosch Group Vaillant Baxi

Reasons to choose British Gas

Fixed price quote

We guarantee a fixed price

When our Heating Advisors quotes a price, we guarantee it won’t increase even if there’s unexpected work to do.

Boiler cost calculator

No deposit

Pay monthly with no upfront deposit

We could help you spread the cost over 3-10 years or you could choose to pay in full if you’d prefer.

Payment options

Your home is left clean and safe

Your home is left clean and safe

Our Engineers leave your home neat and tidy and will arrange the safe disposal of all waste.

Step by step guide

Free aftercare

Aftercare included

This offer includes HomeCare 200™ which provides service and repair for your boiler, controls and central heating system for one year.

Latest offers

British Gas New Heating Limited is authorised and regulated by the Financial Conduct Authority for its consumer credit activities.

* Based on 546 customer responses collected between 09/12/14 & 12/12/14.

We value the honest feedback of our customers, so we've partnered with Reevoo - an independent reviews service. Reevoo collects ratings and reviews from people who shop with us. Using a third party ensures there is no bias, editing or fake reviews.

British Gas Boiler Installation Service reviews verified by Reevoo

Quality of the installation
Quality of advice provided by the Heating Adviser (person who gave you your quote)
Overall rating
Scores 8.8 out of 10 based on 1460 reviews
10 out of 10


Glasgow GB
The heating advisor, Angela, was excellent and thorough and the guys who installed it were also. It is a bit more expensive than other boiler installers but probably worth it for peace of mind and the fact the boiler is installed quickly with absolute minimum disruption.
Published on: 29 January 2015
10 out of 10


Harrogate GB
Entirely satisfied with the installation of our new central heating boiler.
Published on: 29 January 2015
9 out of 10


Baildon, Shipley GB
Boiler installation good but the installation of the free smart meter has been disgusting and still not working properly all because the installation engineer gave the wrong meter number to the system . I have ended up with someone else's meter and this was only spotted by the other customer. I was phoned three days ago to say this was being rectified and someone would call me back but as of today 14.01.2015. nobody has bothered. It would appear to me that your smart meter department is totally incompetent and the gas side of the smart meter will not be working until the earliest February 2015. This is not good enough as I have paid the full bill for the boiler installation on time and have fulfilled my part of the contract, you haven't fulfilled your part. It sounded as though your guy was doing me a favour telling me that a mistake had been made. I have had time off my self employed work to accommodate the change of both boiler and meter installation dates and I now find I have to do it yet again for you to sort out this problem, I would have thought this was an easy task and it is not ROCKET SCIENCE
Mr D. E. Southcott.
Published on: 29 January 2015
10 out of 10


Sheffield GB
The engineer was polite, efficient and did a great job of installing our new boiler
D.C. Sheffield
Published on: 29 January 2015
8 out of 10


Stalybridge, GB
Always satisfied with the jobs with the jobs we have had done
Published on: 28 January 2015
10 out of 10


tipton GB
Excellent service
Published on: 28 January 2015