Free Quote
Platinum Boiler Installations Logo

Read our genuine reviews left on

Call our boiler installation team

Get A Quote
What Is a Combi Boiler?
Posted in

What Is a Combi Boiler?

What is a combi boiler?

A combi boiler, or combination boiler is a single unit appliance that produces heating and hot water on demand when you need it. Combi boilers are the UK’s most popular choice of boiler. I am going to be talking about the pro’s & con’s of having a combi boiler installed in your home and exactly what you need to know when thinking of purchasing a new combi boiler.


  • Combi Boilers are more economical as you only heat the hot water that you actually require
  • As a combi boiler runs off your cold water main then you get more powerful hot water, as long as your cold water main is adequate
  • You get an unlimited amount of hot water. As long as there is a demand i.e a tap is open, then the combi boiler will keep producing hot water
  • You do not have any tanks or cylinders with a combi boiler so they are great at saving you space
  • As all the components are inside a combi boiler, when having a new one fitted will mean everything within the boiler will be covered by the manufacturer’s warranty as oppose to external pumps, zone valves, vessels etc
  • A combi boiler is usually quicker to install as they have less boiler parts than other heating systems
  • Central heating systems are usually cleaner with a combi boiler fitted as it is a sealed system with no storage tank where rust and debris can build up


  • No back up hot water, as a combi boiler is a single unit appliance it has no cylinder (stored hot water) with an immersion so if your combi boiler breaks down you will have no heating or hot water (un less you have an electric shower fitted)
  • Limited hot water use, as a combi boiler runs off your cold main you will not be able to operate more than one tap at a time without it effecting the other outlet, e.g if you are in the shower and someone runs a tap downstairs it will effect the flow and temperature of the shower
  • Dependence on Cold Water Main Supply, because a combi boiler runs off your cold water main you need to have a good flow rate coming in to your property to achieve the combi boilers hot water outlet
  • So if your house has more than one bathroom and you often use more than one tap/outlet at the same time then you may need some stored water instead of a combi boiler as this will give you enough hot water when multiple outlets are being used.
  • If you have one bathroom or even an en-suite as well with an electric shower then a combi boiler will be more than adequate. Just remember you CANNOT run more than one tap with a combi boiler without effecting another taps flow rate.

What Is a Combi Boiler?

Combi Boiler Quote

Get a FREE Combi Boiler Quote by Clicking Here

Share this post

Matt Hughes

Matt Hughes is the Managing Director of Platinum Boiler Installations and his mission is to make boiler installations as simple and hassle-free for customers as possible. What Matt doesn't know about boilers simply isn't worth knowing! Connect with Matt Hughes on LinkedIn >>

View All Posts

Latest Posts





Established in 2014 to provide a local, quality and affordable boiler installation service. We are a fully insured boiler installation company. Our GasSafe number is 598837.
Google Rating
Based on 93 reviews
© Platinum Boiler Installations
Company Number 10052015
VAT Number GB 252781202
SitemapLegal PagesSite by MRD