What is a Combi Boiler?

combi boiler

What is a Combi Boiler?

Combi boilers are found in over 70% of UK households and are the boiler of choice for new build properties. They provide homes with an instant and continuous supply of hot water and water and are relevantly easy to install. An attractive proposition for a new build.

Combination or Combi-boilers are a specific type of space-saving condensing boiler becoming increasingly popular in UK houses due to their impeccable efficiency.  Small and compact, combi-boilers work as both a water heater and a central heating boiler in one compact unit.  With houses becoming increasingly smaller, and bills getting gradually higher, these compact, money-saving “combi’s” are the perfect choice for any small home.  Combi boiler prices vary dependent on make, model and size.

Types of Combi Boilers

If you believe that a combi-boiler is the best choice for you and yours, then there are essentially two options open to you: a Gas-Combi and a Heat-Only Combi.  Here we review the two options – advantages and disadvantages – for you, your home and your bank balance.

Gas Combi

  • Advantages

The main advantage to choosing a combi-boiler is the compactness of the unit.  You don’t need the usual water cylinders that come as part of the traditional boiler make up.

Most combi-boilers come with thermostat controls as standard so you are safe from sudden temperature fluctuations – no more cold water shocks!

The fact that it heats water on demand means you won’t have to wait for water to heat up, the stream of hot water is instantaneous – perfect if you live in a busy, full household or a house share.

These boilers are environmentally and economically efficient which means you save a huge amount of money in the long-run.  Monetary savings are always an important aspect when choosing a boiler, and you won’t find a better option out there for this type of saving and efficiency.

Finally, with no tanks or pipe work to install the installation is faster and easier than traditional boilers, while, because combis are so common, boiler service costs are relatively low and parts and engineers are easy to find.

  • Disadvantages

While combi-boilers have many advantages there are a couple of disadvantages you need to bear in mind.

In order to get hot water on demand you need to have an adequate supply of water.  If you have a large number of taps or showers using the hot water supply simultaneously, the pressure to each will drop substantially.

As the water is heated straight from the mains if you suffer from sudden pressure drops or are likely to have a large number of taps in use at the same time then it is probably not the right boiler for you.

Furthermore, if you are switching from a more traditional boiler to a combi-boiler the initial installation cost can be fairly steep.  However, the money you will save in the long run, thanks to its efficiency should more than make up for this start-up cost.

Heat Only

Heat-only boilers were the norm until the 1970s.  They supply heat directly to radiators and heat up water which is then stored in a hot water cylinder.

  • Advantages

The main advantage to having a heat-only boiler is that they are much better at coping with multiple occupants utilising the hot water at the same time – large households with two or more bathrooms for example.

Changing or replacing a heat-only boiler is also incredibly easy as it can normally slip in to the pre-existing central heating system making installation easy and fuss-free.

Heat-only boilers are easy to maintain due to their simple design and, unlike combi-boilers are ideal for use in places where water pressure is low.

  • Disadvantages

The obvious disadvantage of a heat-only boiler is the amount of space it takes up in a household.  With a boiler unit and hot and cold water tanks needing to be stored, you need to have the space in your house to store all these utilities.

A heat-only boiler heats water and stores it in a cylinder.  If poorly insulated heat loss can occur meaning the water needs to be re-heated, thus lowering the efficiency and costing you more money.

This hot water storage cylinder can only hold a certain amount of water.  Unlike a combi-boiler it doesn’t heat water immediately, this means that, if a lot of people are using hot water, you could find yourself out of hot water and having to wait around for the boiler to heat more water.

Get a Free Combi Boiler Quote