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Heating oil explained

What is heating oil?

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What is heating oil?

We talk you through the basics of heating oil, including the different types of heating oil, what they're used for and the average prices.

Around four million households in the UK are not connected to the national gas grid, and instead rely on heating oil, liquid petroleum gas (LPG), electricity or renewable sources to heat their homes. 

The key difference between energy from the grid and heating oil (as well as LPG) is that heating oil is delivered by road and stored in a tank.

If you're home has an oil boiler, your house runs on heating oil. Keep reading to find out what you need to know about heating oil.

You can use our research to discover the most reliable oil boilers.

Types of heating oil

Two types of heating oil are used for domestic heating:

  • Gas oil – also known as 35-second oil or red diesel. This is a heavier oil generally used in older boilers, in agriculture or commercially.
  • Kerosene – also known as 28-second or heating oil. This is a lighter and cleaner fuel and the most common type used in homes in the UK.

If you've just moved into a property, the type of oil you will need is determined by the type of heating system already installed in the house. If your boiler or tank isn't labelled clearly, ask the previous owner what type was used. If they can't help, a technician registered with Oftec (the oil-fired industry trade association) should be able to tell you.

If you are able to choose which type of heating oil to use, kerosene is more efficient.

If you are able to choose which type to use, kerosene is the more efficient fuel. In cold weather it is unlikely to ‘wax up’ (form crystals that stop it from flowing as easily) until it reaches around -39°C (although check with the supplier on the type you're getting, as this can vary). 

For more information on how to prevent waxing up, take a look at our tips on maintaining and fixing heating oil problems

Kerosene heating oil

You can buy a premium type of kerosene that contains additives - this makes it burn more cleanly and therefore more efficiently. Premium kerosene usually costs around £20 to £30 more than standard kerosene (based on 500 litres). You can also buy additives yourself, which cost around £15 for a bottle that will treat 1,000 litres of heating oil. 

For certain appliances, such as an Aga, you are required to use additives - you should be able to find this out from the manufacturer.

Heating oil prices

In January 2017, the average price for a litre of kerosene was 43p (source: Sutherland Tables, which collects domestic fuel pricing data from across the UK).

But the price of heating oil can fluctuate. For example:

  • January 2017, 43p per litre
  • January 2016, 32p per litre
  • January 2015, 46p per litre. 

This can be because of global production or political unrest, but it can also depend greatly on where you live in the UK, the time of year you buy and the amount you buy.

There are several ways to get a cheaper deal - find out more about how to get the best heating oil prices

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