Get the hottest deals
Get a fixed price in 20 seconds & installation as quick as tomorrow.
The Worcester Bosch Greenstar Heatslave II External is designed for external installation, oil-fired and energy-efficient.
The Worcester Bosch Greenstar Heatslave II External will not be a disappointment. It’s designed to be fitted outside so you don’t have to worry about it taking up and valuable indoor space.
It comes complete with a green-coloured cabinet to blend in with your garden too. Not only that but the Worcester Bosch Greenstar Heatslave II External is both solar and smart compatible.
It achieves an A rating for efficiency and it has even achieved Which? Best Buy.
You will find the Worcester Bosch Greenstar Heatslave II External priced between £2,400 and £2750 because it is available in three central heating outputs that are 18kW, 25kW and 32kW. You can expect to pay more for the higher output.
You have to consider the cost of installation as this is not included in the price.
If you would prefer a boiler to include installation fees, go to
This oil-fired combi needs to be installed outside.
It doesn’t require any loft tanks or a separate cylinder for storing hot water. This makes it a great choice if your home is short on space.
Just like with other combi boilers, the Worcester Bosch Greenstar Heatslave II External takes water from the mains to provide you with hot water and heat your radiators on demand.
It comes in three central heating outputs, so you need to make sure you are selecting the right size for your home. Your Gas Safe engineer can help with this decision.
Usually, the bigger the property, and the higher the demand for heating and hot water, leads to the need for the higher the kW output. You want to make sure it can meet your needs and also run efficiently.
As with the internal model, the Greenstar Heatslave II External has some excellent controls and features.
These include an Eco Hot Water Mode that saves energy, a one-piece baffle for easy servicing, and inbuilt frost protection.
You will find the controls sealed in a drawer and the boiler itself comes in a green powder-coated cabinet to make sure it is protected from the elements and doesn’t look out of place in your garden. Certainly, something that most people would be concerned with.
This model can also be used alongside water that is heated from green sources and it can be connected to a range of optional energy-efficient controls to reduce your fuel bills more.
A great feature that gives you the ultimate control over your boiler, is the Bosch EasyControl smart thermostat that lets you manage and monitor your central heating and hot water from a smartphone or tablet.
This boiler comes with 2-year parts and labour warranty as standard.
This may mean that you want to consider researching and adding on additional protection that may last longer. A great way to do this is to look at the Worcester Bosch website to see if there are any existing offers or promotions on oil-fired boiler warranties before you purchase.
Always follow the guidelines which you can read here, to ensure you keep the warranty valid.
It’s difficult not to fall in love with the Worcester Bosch Greenstar Heatslave II External, It’s considered one of the UK’s most popular oil-fired combi boilers.
Below, you will find a list of all its pros and cons.
2-year warranty, a longer guarantee would be better.
Get a fixed price in 20 seconds
What fuel does your boiler useCompare Quotes >
Stressed when needed a new boiler but easy process with affordable finance. New boiler installed within a few days with option for next day.
On the day, they came on time. Lovely people, they kept everything clean. Explained everything to me. No mess, kept me informed.
Great experience - quick to arrange, easy to work with the very responsive online team and all installed faster than expected.