Worcester Greenstar 4000 21kW System Boiler
The Worcester Greenstar 4000 21kW System Boiler is the direct upgrade of the Greenstar 21Ri, designed specifically for medium-sized homes with one or two bathrooms. Compact, wall-mounted, and modern in design, this system boiler combines high efficiency, quiet operation, and user-friendly controls to deliver reliable heating and hot water for your home.
Efficient Heating and Hot Water
With a wide power range and ErP A-rating, the Greenstar 4000 21kW is engineered to reduce gas consumption, helping to lower your energy bills. It is designed for homes with a hot water storage cylinder, providing sufficient hot water even for multiple bathrooms, making it a practical solution for medium-sized households.
Modern Features for Easy Operation
This boiler features a full-colour text display for intuitive operation, ensuring all controls are simple to navigate. Its quiet design makes it one of Worcester Bosch’s most unobtrusive system boilers. For added convenience, it supports wireless connectivity with the Bosch EasyControl, allowing you to monitor and adjust your heating remotely. It is also compatible with Greenskies solar panels, promoting energy savings and eco-friendly living.
Key Features & Benefits
Heat output: 21kW – ideal for medium-sized homes with one or two bathrooms
ErP A-rated efficiency – helps reduce fuel costs and carbon footprint
Quiet operation – one of Worcester’s quietest system boilers
Wireless connectivity – compatible with Bosch EasyControl
Easy-to-use full-colour display – intuitive interface for all settings
Suitable for hot water storage cylinders – reliable hot water supply for multiple bathrooms
Greenskies solar panel compatible – reduces energy usage and costs
Compact wall-mounted design – dimensions: 724 x 400 x 310mm (HxWxD)
7-year manufacturer guarantee – for peace of mind
Technical Specifications
Brand: Worcester Bosch
Model: Greenstar 4000 21kW System (7733600383)
Boiler Type: System Boiler
Fuel Type: Natural Gas
Heat Output: 21kW
Mounting: Wall
Dimensions (HxWxD): 724 x 400 x 310mm
Colour: White
Weight: 30.6kg
ErP Rating: A
EAN: 4057749856722
Product Code: PN183939
FAQs
Is this boiler suitable for medium-sized homes?
Yes – with a 21kW output, it is ideal for **medium-sized homes with one or two bathrooms**.
Can it work with solar panels?
Yes – the Greenstar 4000 21kW is compatible with **Greenskies solar panels** for enhanced energy efficiency.
How long is the warranty?
This boiler comes with a **7-year manufacturer’s guarantee** for long-lasting reliability.
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