Skip to content

Gas Boilers – Which Type Do You Need For Your Home?

When installing a gas boiler in a new construction, or replacing the existing boiler in your home, deciding on the model required can take a significant amount of time.

It’s not always the best idea to simply replace the existing boiler with exactly the same model. Previous tenants may not have chosen wisely or it may have been discontinued. The cost efficient option might not always provide you with the high performance of gas boilers that are a little more expensively priced.

Cost efficiency in purchase may not translate well into effectiveness in use. There are three main types of gas boilers to choose from – conventional, combination and system.

Depending on circumstances, each type can offer a variety of benefits.


Conventional gas boilers are considered to be the traditional boiler of choice – the one installed in most homes up-and-down the United Kingdom.

They are easily identifiable because they make use of an external tank, which they use to store heated water.

These boilers are attached directly to the mains. A conventional boiler is very useful if your home has more than one bath and if the mains pressure is low. With a low water pressure, it becomes important to generate heated water that can be stored, as this could not be done fast enough to sustain a heated flow for use.

These types of boilers used to be known for their lack of energy efficiency, but newer models have become significantly more efficient.

You must make sure that you have the space to install this type of boiler and tank before deciding whether or not to make a purchase.


Combination gas boilers are smaller than the conventional style.

Rather than attach directly to the mains, they hook into the lines within the house. They are dependent on high pressure from the mains supply; these boilers can produce considerable amounts of heated water, quickly, for immediate use.

They do not need a storage tank and are an excellent choice for homes with one bath, or a history of very little water usage.

Some of the newer styles of combination (or combi) gas boilers are very small, making them a perfect under-sink option. These very small boilers only provide heated water to the appliance directly connected to them. However, they score high on energy efficiency, and can be a good choice for keeping your utility bill low.


System gas boilers are not an option that many people can consider. This is because they’re only compatible with homes constructed in specific ways. These boilers serve the dual purpose of heating water for use by appliances and by the heating system in the house.

If your house does not use heated water as its room heat source, then this style will not be effective for you. The cost effectiveness of this model is based in its reducing the need for two separate boilers. The downside can be the broad ranging effect on your quality of life should something go wrong with the boiler.

Always make sure that the boiler is installed by a professional qualified with the Gas Safe Register. While you can perform many of the service and maintenance processes yourself, it is best to let a professional install the unit due to safety issues.

Louisa Jenkins is a blogger, who has a love of interior design. As well as documenting aesthetic elements, Louisa also likes to write about the home’s more basic, vital elements, such as gas boilers, plumbing and waste management.