What Is A Combi Boiler?

Combination boilers – more often than not are referred to as combi boilers – tend to be the most in-demand type in the United Kingdom and supply heat as well as domestic hot water with the necessity for water holding tanks or perhaps cylinders. You’re able to select either a gas, electric, or maybe an oil combi boiler.

We provide new combi boiler installations in London, you can call us for a free no obligation quote for your house or commercial boiler installation or repair needs:

CW Plumbing and Heating Ltd.

020 7733 6812

How does a Combi Boiler Work?

Baxi Combi Boiler
Combi Boiler, (Baxi)

They furnish home heating and also domestic hot water straight from the boiler. A combi (or else combination) boiler is undoubtedly an innovative space-saving concept, as well as a more popular then ever preference in UK households. The truth is, combis today make up in excess of 50 % of all the completely new residential boilers hooked up in Great Britain each and every year.

You’ll find it both equally a high efficiency hot water heater as well as a central heating boiler, combined (henceforth the name) within just a single compressed unit. For that reason, simply no standalone hot water storage container is necessary, offering up space-saving around the home.

Even more advantages of a combi boiler include things like running hot water getting sent through the faucets or shower head at mains pressure. Which means you can benefit from highly effective showering and speedy back filling bathtubs, without having to use a water pump. Nonetheless, the hot discharge could be restrained any time a variety of taps tend to be operating simultaneously.

An independent temp regulator for both the central heating system and the hot water flow will increase your safety and comfort by providing you with with additional control over calibrating the temperature settings in addition to the water pressure.

Save Money on Combi Boiler Installation Costs

Another advantage would be that it will usually help you save money on boiler installation time and costs, given that with no water tank inside the roof structure area will mean significantly less piping which equates to a reduced installation time.

The domestic hot water is supplied through the cold water mains system which goes through a heater exchanger within the combi boiler and will be heated up on-demand, when we say “on-demand” We mean if you need fast hot water you open up a tap, the boiler subsequently heats up the water stream prior to it arriving at your chosen tap outlet. Once you’ve got finished cleaning the pots and pans or perhaps having a shower, you can shut the tap off, which then delivers an alert to the boiler (by way of a flow switch) and then the boiler ceases heating up the water.


Combi Central Heating boilers operate in exactly the same way, the hot water stream is moved throughout the central heating system circuit whenever you “call for heat” by way of a room or space stat/programmer, as soon as the requested room temperature is attained the central heating boiler turns off.

Condensing Combi Boilers

The combi boiler will now condense, meaning that it will cool-down the flue gases in order to generate energy, this in turn increases overall performance and brings down operating costs, using this method creates a build-up of moisture build-up or condensation that is acidic, the condensate simply leaves the boiler by way of a plastic-type pipe and will terminate in a designated drain or perhaps waste pipe (therefore please remember you’ll want to locate your new boiler in close proximity to a drain).

Vaillant Combi Boiler
Combi Boiler, Vaillant

The new condensing combi boilers are usually fan fled, meaning that there is a fan that is utilized to draw the vapour into the outdoor air through the flue, using this method enhances the health and safety of your equipment, because the boiler won’t “fire-up” unless of course the fan is operating.

Enjoy the Benefits of a Dual Purpose Operation of Combi

The combi boiler was created to supply heating to the radiators as well as domestic hot water outlets on-demand. The branding originates from the simple fact that it brings together all of the characteristics of the conventional boiler, domestic hot water storage container and also cold water tank set up. All the most important components are housed in the one unit, leading them to be exceptionally convenient to put in.

Whenever you turn on the tap, water flows from the mains supply, heated up within the boiler mechanism and then will come directly from the tap steaming hot. Storage combi boilers are also offered you might like to employ a smallish stash of hot water.

6 Most Important Combi Boiler Benefits:

  1.  Instant, unrestricted flow of hot water – no waiting around for the hot water cylinder to refill.
  2. A cost-effective option for smaller sized homes which have lower hot water requirements.
  3. Smaller heating-systems – combi boilers clear away the dependence on a cold water storage tank, domestic hot water storage container in addition to the airing cupboard.
  4. Drinkable water available at all your taps – as it is delivered directly from the basins supply.
  5. Combi boilers can supply from between 9 to 18 liters of water per minute (in the event the cold water supply is heated by 35°C).
  6.  You can easily enjoy a powerful shower right off the shower taps using a combi boiler.

What is the Best Combi Boiler

Per chance your boiler packs up on you, lots of people find it easy to simply take the first quote that comes along, so they can get their heating system back up and operating as soon as possible, nevertheless, you could possibly be creating trouble for yourself should you make a bad choice. Because, good combi boilers really should last you at the very least 15 years or even more, for that reason be sure you make a good decision up-front!

Combi Boiler Installed on Kitchen
Combi Boiler Installed in Kitchen

Which is the Best, Combi or Heat Only Boilers?

Combination (AKA combi boilers) and heat only boilers (quite often categorised as regular or conventional boilers) are equally quite distinct – heat only boilers always have a hot water cylinder in which the heated up water is retained. Whereas combis generate very hot water on-demand, whenever you require it. There isn’t any cast in stone principle regarding which is going to be the best for any particular home, as both of them can be quite efficient in their own way. Generally combis go very well in the smaller sized residences as you don’t require a domestic hot water tank in addition to any cold water tanks – this is going to save valuable space, whilst the heat only boilers can deliver pressurise hot water to numerous taps simultaneously, so these you will find will be more appropriate for larger sized homes.

What exactly do boiler owners say?

There are several consumer surveys bumping around on the internet and the opinions you will find there are most often the recommended trend: Worcester and Vaillant boilers are likely to be on top of the stack on the list of the major brand names, whereas IHalstead, Vokera , Ideal, and Ferroli are apt to have probably the most criticism.

Which Combi Boilers We Suggest?

Numerous qualified home-based trades individuals who source and put in countless boilers each and every year often will recommend either Baxi Boilers or Vaillant boilers. They generally tend to be really dependable and they are excellent value for the money.

Call Us 7 day 24 hour for Combi Boiler Installation in London  020 7733 6812