The Worcester Bosch
Greenstar 4000.
A 21kW system boiler from Worcester Bosch — installed in a single day by Gas Safe registered engineers.
Built for real homes.
Not showrooms.
The Worcester Bosch Greenstar 4000 21kW is designed to work quietly, efficiently, and reliably — for years to come.
- Quiet Operation
- 21kW heat output — System boiler
- 21kW central heating output
- 8 year manufacturer warranty
- 94% ErP efficiency rating
One price.
Everything covered.
No surprise add-ons. Your quote covers everything needed for a complete installation that meets all gas safety regulations, carried out by Gas Safe registered engineers.
Price and installation time varies depending on your installation requirements. Answer a few quick questions to get your exact fixed price.
Get your free quoteThe numbers
that matter.
Worcester Bosch Greenstar 4000 21kW
The Worcester Bosch Greenstar 4000 21kW combines reliable heating performance with upgraded controls and modern styling. Featuring a full-colour display and Bosch EasyControl compatibility, it is designed to make managing your heating straightforward and convenient.
Quiet Mark approval and warranties of up to 10 years help make the Greenstar 4000 21kW one of Worcester Bosch's leading system boilers.
Don't let cost get
in the way of warmth.
Spread the cost of your new boiler over monthly payments that fit your budget. Available through iDeal4Finance — apply in minutes.
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