PD Plumbing Supplies Explains The Difference Between Kerosene, Gas Oil And Diesel

What is the difference between kerosene, gas oil and diesel and can my oil-fired burner use all three?

What is Kerosene?

Kerosene is a low-sulphur and clean burning oil which is used in the majority of modern oil-fired boiler units. It is also used to fuel Aga stoves (and similiar models). It is also known as paraffin. Interestingly, kerosene is the fuel used to power jet aeroplaness too! Because it burns cleanly it economically produces a high level of heat. Kerosene is the only fuel oil suitable for use with an indoor oil-fired boiler and condensing oil-fired boilers.

Gas Oil and Diesel

Gas oil and diesel are virtually the same. The fact that they are so similiar is the very reason why a dye is added to gas oil in order to distinguish it from diesel (sometimes you will see pumps with the label 'Marked Gas Oil'). A diesel car or van engine can run on gas oil, however, since gas oil has a lower tax added to its price it is not allowed to be used by regular motorists. The dye allows the authorities to check if motorists have filled their car or van's diesel tank with this cheaper product!

The minor difference that exists between diesel and gas oil is in the sulphur content. Gas oil may contain up to 0.1% sulphur whereas diesel may only contain a maximum of 0.001% sulphur. Recent legislation in Ireland requires that gas oil be very low in sulphur.


Be careful where you buy your diesel - Unfortunately some fuel stations supply 'diesel' which is actually gas oil that has had the dye removed illegally by 'diesel launderers'. Since the origin of such laundered fuel is unknown it could contain high levels of sulphur, thus it can damage some modern diesel vehicles requiring low-sulphur diesel.

Can I Use Kerosene, Gas Oil and Diesel to Fuel My Home Heating Boiler?

The majority of oil-fired burners are set to run on kerosene by default. In general, gas oil and diesel can be used to fuel oil-fired home heating systems, and the majority of Riello burners supplied by PD Plumbing Supplies can run on all three fuels. It is important to note that diesel or gas oil cannot be used as fuel for condensing boilers, and they should only be used in an outdoor boiler that is fitted with a conventional vertical flue. Burning diesel or gas oil is not permitted where a low level flue is fitted.

In order to burn diesel or gas oil, the burner unit would have to be set up differently than a burner used to burn kerosene. The fuel spray nozzle needs to be smaller and the fuel pressure needs to be higher. The air intake (air linlet) also needs to be adjusted. It is very important that a registered OFTEC technician carry out this set up. A competent technician will have the required pressure testing equipment. It is not a complicated task and it should not take long or cost very much.

Since diesel and gas oil are more expensive than kerosene, using diesel/gas oil would only make sense where this fuel is bought in bulk, such as by those in the agriculture industry. Some say that burning diesel/gas oil instead of kerosene results in less wear on the burner, but when you consider that a new burner only costs Ä250 euro (in most cases) and lasts 10 years or more, it is hard to see how using diesel/gas oil could be more economical for the average consumer.

For more information, please don't hesitate to contact PD Plumbing Supplies. We will be glad to advise you on the best burner and fuel options for your particular setting.