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Best Oil Boilers

Best Oil Boilers

Although, oil boilers tend to be less common than gas boilers, around four million UK homes are not on the national gas grid. Therefore, these properties need an alternative to gas. Of course, electric boilers are a viable option, especially considering there will be government restrictions on gas and oil boilers by 2025. However, the expensive running costs of electric boilers can often result in oil boilers being the best option for the immediate future.

How Does An Oil Boiler Work?

An oil boiler works in a similar way to a gas boiler. When water enters the boiler, the oil becomes ignited in the combustion chamber. It then passes via a heat exchanger, which provides hot water and heating to your home, through radiators, taps and showers. To have an oil boiler, you will need to ensure that you have the space for the unit’s fuel tank. This is down to the fact that the boiler requires somewhere to store the oil until it is needed.

Best Oil Boiler Models

Now that you are equipped with a basic understanding of how an oil boiler works, the next section of this guide will introduce you to some of the best oil boilers available.

Vitorondens 200-T

The Vitorondens 200-T from Viessmann is a cast-iron condensing boiler. Perhaps, this model’s most impressive feature is its efficiency. The Vitorondens 200-T has been rated 97% for its ability to save energy, meaning with this boiler you can drastically reduce your energy bills. This model is fitted with an Inox-Radical heat exchanger made from stainless steel, which operates alongside a Eutectoplex heating surface. This modernised technology means that Viessmann has produced a reliable, long-lasting boiler with the Vitorondens 200-T.

Greenstar Heatslave II

Worcester Bosch’s Greenstar Heatslave II is the UK’s most popular oil combi boiler. This boiler comes in three different power outputs, from 18 to 25 and 32kW. Its compact design means it can be installed under a standard-size worktop in the kitchen, making it the ideal boiler for smaller homes with limited living spaces. This model is compatible with a range of optional controls, allowing you to optimise the settings for your home’s heating and water temperatures.


The VortexBlue from Grant has been designed for kitchen and utility room environments. Instead of using the usual yellow colour of standard burners fitted in the Grant Vortex Boilers, this model has been fitted with a revolutionary blue flame burner. This blue flame results in a cleaner combustion process, meaning the boiler produces lower emissions.


The Agentis internal oil boiler from Warmflow has an efficient, patented stainless steel heat exchanger. This is partnered with the latest Riello low NOx burner technology, making it the UK’s only AAA-rated boiler. Its high-end energy efficiency, allows it to save an average of five litres of fuel per week when compared to other brands. This model’s slimline design means it can be seamlessly integrated into any kitchen or utility room.

Mistral Sealed System – Condensing Oil Boiler

The Mistral Sealed System is a small, compact oil boiler. At just 41cm wide, this boiler can be installed in a variety of locations within your home. However, if you do not have the required space, then this model can be fitted outside your property. This boiler’s efficiency means it is environmentally friendly, and therefore economical to run. This unit is available in a multitude of outputs, ranging from 15 to 41kW, making it suitable for different property sizes.

Worcester Bosch Boiler

Homeowners are still able to get a FREE boiler grant or insulation grant via the ECO scheme, which is still available to households that qualify. Warma UK are currently working throughout the UK helping privately owned and rented homes to improve home energy efficiency and save money on rising energy bills.

For more information email –

Or call 03304600065

Apply For Your Government Backed Heating Grant

Following your successful application, we will arrange a free, no obligation survey to ensure the maximum grant is obtained and advise you on the best products to reduce your homes energy usage.

Michael Cornish