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Worcester Greenstar Heatslave II Oil Combi
- Oil
- Combi
Save Space – Compact design fits neatly under a worktop, freeing up valuable room in your kitchen or utility space.
Instant Comfort – Enjoy hot water on demand with no waiting around.
Whisper-Quiet Performance – Experience reliable heating without the noise.
Flexible Options – A perfect fit for many homes, with sizes available from 12kW to 32kW.
ErP Efficiency Rating: Heating – B, Hot Water – A
Fuel Type: High-efficiency oil boiler
Smart Control Options: Compatible with Worcester Bosch EasyControl
Renewable Ready: Solar compatible for future-proof energy savings
Central Heating Output: Up to 18kW – perfect for small to medium homes
Hot Water Flow Rate: 15 litres per minute for strong, reliable performance
Compact Dimensions (HxWxD): 855 x 520 x 600 mm – fits neatly into utility rooms or kitchens
7-Year Guarantee – enjoy complete peace of mind with long-lasting reliability
Energy Efficient: ErP Rating A for low running costs
Oil-Fired Reliability: Powerful heating for homes of all sizes
EasyControl Compatible: Smart, user-friendly control options
Solar Ready: Integrates seamlessly with solar systems
High Output Options: 50 kW or 70 kW central heating
Compact Design: Space-saving dimensions suitable for indoor or outdoor installation
What’s Included with The Boiler Team Installation?
Installed by a local Oftec engineer
Oil Filters / Fire Valve Upgrade Pack Included
Old boiler & tanks removed (if applicable)
All waste cleared, including old boiler
Flue installation for optimal performance
Magnetic filter to protect your system
System cleanse + protective treatments included
Pipework upgrades where required
Premium copper & fittings supplied
Electrical setup, including wireless thermostat (if applicable)
Delivery & setup arranged for you
Warranty registration & certification handled
Manufacturer parts & labour warranty included
10-Year workmanship guarantee from The Boiler Team
Frequently Asked Questions About Worcester Bosch
Find answers about Worcester Bosch boilers, including combi, system, and conventional models for gas or oil. Get the key info you need to choose the right boiler for your home.
The Worcester Bosch Greenstar Heatslave II is one of the UK’s most popular oil-fired combi boilers, designed to deliver both central heating and hot water on demand. Compact, efficient, and reliable, it’s ideal for homes without access to mains gas.
Yes. With an ErP efficiency rating of A for hot water and B for heating, it’s built to reduce running costs and maximise energy savings.
The 12/18 model, with an 18kW heating output, is perfect for small to medium-sized homes that need strong hot water performance and steady heating.
This oil combi boiler provides an impressive 15 litres per minute, ensuring powerful showers and quick-filling baths without long waiting times.
Yes, it’s fully EasyControl compatible, giving you the ability to control your heating remotely via smartphone or tablet.
Absolutely. The Heatslave II is solar-ready, meaning you can integrate renewable energy for even lower running costs.
It has compact dimensions of 855mm (H) x 520mm (W) x 600mm (D), making it suitable for kitchens, utility rooms, or even some garage installations.
Built by Worcester Bosch, a brand renowned for quality, it’s engineered for durability and backed by excellent aftercare, with long guarantees available when installed by a Worcester Accredited Installer
This boiler is designed for oil-fired heating systems, making it a great choice for homes off the gas grid.
When installed by a Worcester Accredited Installer, you can benefit from a guarantee of up to 7 years, giving you peace of mind on your investment..
Boiler Finance Available
Spread the cost of your new boiler.
