When it comes to choosing a new boiler, we at K&M Maintenance are quite the experts. There are two types of boiler to choose from, the conventional boiler and the combination boiler, and there are also issues of space, energy efficiency and construction to think about.  This guide will help you make an informed decision about which type of boiler is right for you.

Conventional boilers

Conventional boilers use a large tank to supply hot water, where the water is heated within the boiler using cast iron heat exchangers. This means that a conventional boiler can supply gallons of hot water at a time, but once the tank runs out, it may take a little time to refill.

Combination boilers

Supplying water direct from the mains, combination boilers (or combi-boilers as they are often called) don’t need a large storage tank. Instead they are able to supply an unlimited amount of hot water when demanded; although homes with multiple bathrooms may see a decrease in pressure, when hot water is being used in more than one place at a time.

So what about the key issues?


Clearly a combination boiler is likely to take up less space than a conventional boiler, due to the fact that it doesn’t require a storage tank. In conventional boilers the cold water storage tank is usually in the loft or attic as the extra height can provide more pressure, which means if you are thinking of fitting a conventional boiler, you will also need space for the tank. Combination boilers on the other hand, can fit into kitchen or bathroom units easily due to their compact size.

Energy efficiency

In terms of energy efficiency, the combination boiler tends to be the stronger of the two candidates, mainly because their popularity has meant that their designs have remained modern, where many conventional boilers are now more traditional. For example, many combi-boilers can be set to an ECO mode, or be controlled via a Smart Home products, which gives you more control over temperatures and settings even when the boiler is in standby mode.

All boilers are rated for their energy efficiency, with an A grade boiler being the most energy efficient.


Pipe work both from the mains and to the cold water tank means that in general conventional boilers take longer and are more complicated to fit, in comparison to combination boilers which tend to have minimum piping and be easy to install.

In summary, there are many benefits to a combination boiler, including the ease of installation, the smaller space requirements and the fact that they are more likely to be energy efficient, but conventional boilers still provide a good quality water pressure.