Types of Oil Fired Boilers
Hertfordshire (Herts), Bedfordshire (Beds) and Buckinghamshire (Bucks)

Oil fired boilers can be just as compact as gas boilers; wall or floor mounted, clean and quiet. The two most popular choices of oil fired boiler are standard (conventional) or combination (combi) boilers and these are both available as condensing boilers.

If you are planning to install or replace an existing oil fired boiler, you need to choose a condensing boiler. This is a requirement of the Building Regulations Approved Document L1 for the higher standards for energy efficiency. Each type delivers all the benefits of high-efficiency technology, but which one you choose will depend on several factors, including your property, your lifestyle and the professional advice of our OFTEC registered installer.

If there are exceptional circumstances, for example, where it is not practical or economic, a non-condensing boiler can be fitted and in this case an ‘exception certificate’ will be provided. Our boiler installers will assess if your circumstances are not suitable for a condensing boiler to be fitted.

Standard (Conventional) Oil Fired Boilers

If you are replacing an older model of boiler, the chances are that you will have a standard (conventional) boiler. A typical conventional system incorporates a boiler and extended controls, a feed and expansion cistern, and a hot water cylinder (usually in the airing cupboard), which is often fed by a cold water storage cistern located in the loft.

This type of system is most suitable for larger households where hot water is needed on demand and in significant quantities for heating, baths, washing machines, dish washers and so on.

Combination (Combi) Oil Boilers

The high efficiency condensing combi or combination oil boiler is an ingenious space-saving idea, and an increasingly popular choice in British homes. In fact, combination boilers now account for well over half of all the new domestic boilers installed in Britain every year.

The major difference between a combi and any other type of boiler is that a combi eliminates the need to store hot water - so there is no hot water cylinder in the airing cupboard. It is both a high-efficiency water heater and central heating boiler, combined (hence the name) within one compact unit which usually sits in the kitchen or utility room, or sometimes in the airing cupboard. The space savings result from the fact there is no hot water storage cylinder, cold water storage cistern in the loft or other familiar components of a standard (conventional) heating system.

The further benefits of this are a significant saving on fuel costs, and the fact that hot water is delivered through your taps or shower at mains pressure. So you can enjoy powerful showering without the need for a pump. Another benefit of combination boilers is that it can generally save you money on installation time and costs, since no tank in the roof space means less pipe work and a shorter installation time.

Combi boiler systems are generally more suitable for smaller households, flats and bungalows where space is at a premium and there are a smaller number of users with modest heating and hot water demands, although some of the latest combination boilers can suit larger households.

Condensing Oil Boilers

Both standard and combi boilers are available as condensing boilers. Condensing oil boilers are designed to recycle the heat with an extra heat exchanger so that the hot exhaust gases are used to pre-heat the water in the boiler system, therefore reducing energy consumption and costs. Condensing boilers cost a little more but the energy savings will repay that extra initial investment in 2 to 4 years of normal use.

For more information on condensing boilers, please see Condensing Boilers and Condensing Boilers FAQ or visit SEDBUK (Seasonal Efficiency of Domestic Boilers in the UK) for some useful facts and figures.