Worcester Greenstar 4000 21kW LPG System Boiler
The Worcester Greenstar 4000 21kW LPG System Boiler is the ideal choice for medium-sized homes with one or two bathrooms. Designed as the direct upgrade to the Greenstar 21Ri, this modern boiler combines outstanding energy efficiency with a sleek new look, a full-colour text display, and whisper-quiet operation.
Engineered for reliability and performance, the Greenstar 4000 ensures your home stays warm and comfortable all year round while keeping your energy bills low.
Efficient, Quiet and Smart
With an ErP A rating for efficiency, the Greenstar 4000 21kW LPG System Boiler helps reduce gas consumption and energy costs without compromising performance. It features a wide modulation range, intelligently adjusting its output to meet your heating and hot water demands efficiently.
As Worcester Bosch’s quietest system boiler, it operates discreetly, making it a great fit for homes where space and comfort are priorities.
Modern Design and User-Friendly Controls
The Greenstar 4000 range introduces a contemporary new design with a clean, white finish and an intuitive full-colour text display, making it easy to set, monitor, and adjust your heating.
It’s also wirelessly compatible with the Bosch EasyControl system, giving homeowners complete control over their heating from anywhere, via smartphone or tablet.
Versatile and Future-Ready
Perfect for homes with a hot water storage cylinder, the Greenstar 4000 21kW LPG System Boiler provides efficient central heating while ensuring your stored water is always ready when needed.
It’s also compatible with Worcester Bosch Greenskies solar panels, allowing you to integrate renewable energy for even greater energy and cost savings.
Built for Efficiency and Convenience
Worcester Bosch has designed the Greenstar 4000 range with both homeowners and installers in mind. The boiler’s compact 724 x 400 x 310mm (HxWxD) dimensions make it easy to fit into a variety of locations, while its lightweight 30.6kg build simplifies installation.
Its internal components are also easily accessible for straightforward servicing and maintenance.
Key Features & Benefits
A-rated efficiency (ErP) for heating performance
21kW output, perfect for medium-sized homes
Wide power range for reduced gas consumption and improved efficiency
Exceptionally quiet operation for enhanced comfort
Modern new design with a full-colour text display
Bosch EasyControl compatible for smart wireless control
Compatible with Greenskies solar panels for renewable energy integration
Compact wall-mounted design for flexible installation
7-year manufacturer’s guarantee for peace of mind
Technical Specifications
Manufacturer: Worcester Bosch
Model: Greenstar 4000 21kW LPG System
Boiler Type: System Boiler
Sub Type: Gas System
Fuel Type: LPG (Liquefied Petroleum Gas)
Mounting: Wall Mounted
Heat Output: 21 kW
ErP Rating: A
Colour: White
Weight: 30.6 kg
Dimensions (HxWxD): 724 x 400 x 310 mm
Noise Level: Exceptionally quiet operation
Fitting Location: Internal
EAN: 4057749856722
MPN: 7733600383
Product Code: PN183939
Guarantee: 7 Years
Reliable Heating for Medium Homes
If you’re looking for a modern, efficient, and quiet system boiler that delivers dependable heating and hot water, the Worcester Greenstar 4000 21kW LPG System is an excellent choice. Combining award-winning Worcester Bosch engineering with smart technology and energy efficiency, it’s designed to keep your home warm, comfortable, and cost-efficient for years to come.
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