Worcester Greenstar Heatslave II

The Worcester Greenstar Heatslave II 18/25 oil combi boiler is an ideal choice for medium sized homes with up to two bathrooms. If you are not part of the mains gas network, or you simply prefer to use oil to fuel your central heating and hot water, then take a look at what the Worcester Heatslave 18/25 has to offer.

The company brands this as the country’s most popular oil combi boiler. This is thanks to a host of innovative and helpful features built into the Worcester Heatslave 18/25 as standard. It is also helped by Worcester Bosch’s strong reputation for quality and reliability. They have recently celebrated ten years at the top of the annual Which? Magazine annual boiler report. This is down to models like the Worcester Bosch Greenstar Heatslave 18/25, which is robust and powerful.

When installing an oil combi boiler, you also need to fit an oil tank in order to store fuel. This is an important consideration to make if you are considering replacing a gas boiler, as the tank takes up additional room in or around your property.


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Worcester Heatslave II 18/25 Features


The main Worcester Heatslave II 18/25 features are:

  • Sleek design with concealed controls
  • Eco hot water mode to save energy
  • Fits underneath a standard kitchen worktop for convenience.
  • Precision controls to prevent waste

The numbers in the name of the Worcester Greenstar Heatslave II 18/25 oil combi boiler refer to the central heating output and hot water flow rate. This model outputs 25kW of energy to your radiators and produces 18 litres per minute of hot water for your sinks, baths and showers.

You can take advantage of the clear and precise Worcester Bosch Heatslave combi boiler control panel to ensure that you do not heat your home any more than you need to. This accuracy, aided by the high quality design, means that you don’t waste energy and pay more for your fuel bills than you need to. This model is compatible with EasyControl, the company’s own wifi heating controls for the Worcester Greenstar Heatslave 18/25. Eco hot water mode is available too, which helps you save energy by turning off the preheat option on the boiler. This may take a little longer to heat your hot water, but can make a noticeable difference when it comes to your fuel usage.

The Worcester Heatslave 18/25 also looks great, with a flap disguising the control panel. It will fit underneath your kitchen counter too, making it unobtrusive as it goes about its business heating your home and ensuring that you have all the hot water you need.

You can also use water heated using green methods, such as solar panels or from a wood fired boiler, if you want the Heatslave to run with even greater efficiency.

Worcester Heatslave 18/25 Price

The Worcester Heatslave 18/25 price depends very much on the amount of work needed to fit the boiler and any added extras that you require. One of the major Worcester Greenstar Heatslave oil fired boiler costs is the oil tank itself. If you already have a suitable tank, the job of installing the boiler and getting it up and running will be easier, quicker and less expensive than in homes which need to install a new oil tank at the same time as fitting the new boiler.

Another consideration is where the boiler is situated. If you want to swap your current combi for a Worcester Heatslave II 18/25 in the same location, there will be less labour involved than if you choose to fit it somewhere different from the current boiler. The fitter would have to reroute the pipework and flue in order to accommodate this shift, which will cost more than with a standard swap. You might also find some additional costs if you are considering fitting a Worcester Heatslave 18/25 oil combi boiler to replace a system boiler.

Furthermore, adding one of the additional, external Worcester Heatslave compatible controllers comes with a cost too.

The good news is that the bill from Clever Energy Boilers will not come as a surprise. We send a trusted and professional member of staff to your property to conduct a free, no obligation home survey before any work begins. They take all of the above into account and provide you with a fixed quote, which you can consider before giving the go ahead for the work to be carried out. This means the price you are quoted is the exact amount you will pay.

Worcester Heatslave 2 Range

oil boilers worcester bocheThe 18/25 is part of the Worcester Heatslave 2 range, which is hugely popular in the UK. When it comes to oil combi boilers, more customers come to Worcester Bosch than any other firm. We are Worcester Bosch accredited installers and we are proud to provide our customers with their quality, reliable and robust products.

If you have a small property and require an oil combi boiler, the Worcester Heatslave 12/18 can deal with the demands in an efficient manner. However, larger homes with up to two bathrooms might benefit from the Worcester Heatslave 25/32. Both of these other internal oil combi boilers come with the same winning features as the Worcester Heatslave 18/25 and all are built to the same dimensions, meaning that they will fit neatly into your kitchen.

If you want to free up valuable space within your home, there are three Worcester Heatslave 2 external combi boilers to choose from too. They come in the same specifications as the internal models, in terms of the power they output for central heating and the hot water flow, but they can be located outside the home. They come with external casing to protect them from the elements too.

If you have any questions about the Worcester Heatslave 18/25 or any other boiler in the range, call us on 0330 055 2210.

worcester bosch logo
  • A-rated for efficiency for central heating and hot water.
  • Looks stylish and modern in your home.
  • User-friendly controls.
  • Connectivity is a smooth and simple.
  • Powerful models up to 50kW.
  • Runs quietly in your home.
  • Trusted, industry-leading manufacturer.
  • Highest hot water flow rates of any boiler on the market.

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    What customers say about Clever Energy Boilers

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