Worcester Bosch Greenstar 4000 18kW System Boiler Including Flue & 15mm Scale Reducer

The Worcester Bosch Greenstar 4000 18kW System Boiler Including Flue & 15mm Scale Reducer is a premium heating package designed for homes with a sealed heating system and a separate hot water cylinder. Supplied with a horizontal flue kit and a 15mm Scale Reducer, this complete solution provides reliable, energy-efficient central heating while helping to minimise limescale build-up in hard water areas. Built with Worcester Bosch's renowned engineering, quiet operation, and smart heating compatibility, the Greenstar 4000 offers dependable performance and long-lasting efficiency.

Designed for small to medium-sized homes, the Greenstar 4000 18kW System Boiler features a sleek contemporary design, an intuitive full-colour display, and compatibility with Worcester Bosch EasyControl. Its compact dimensions and installer-friendly layout make it an excellent replacement for older system boilers while delivering efficient and consistent heating throughout the home.

Key Features

• 18kW System Boiler
• Includes Horizontal Flue Kit
• Includes 15mm Scale Reducer
• Fuel Type: Natural Gas
• Designed for sealed heating systems with a separate hot water cylinder
• ErP A Rated for heating
• Up to 94% central heating efficiency
• Quiet Mark certified
• Premium full-colour display
• EasyControl compatible
• Solar compatible
• Wide modulation range for improved efficiency
• Compact wall-mounted design
• Up to 10-Year manufacturer's warranty (subject to installation, registration, use of a Worcester Bosch System Filter, and manufacturer's warranty terms)

Ideal for Modern Heating Systems

The Worcester Bosch Greenstar 4000 18kW System Boiler is ideal for small to medium-sized homes with a sealed heating system and a separate hot water cylinder. It provides dependable central heating while delivering stored domestic hot water efficiently through the property's existing cylinder.

The included 15mm Scale Reducer helps reduce limescale formation, protecting the boiler's heat exchanger and supporting long-term efficiency, particularly in hard water areas.

Powerful Central Heating Performance

Delivering an 18kW central heating output, the Greenstar 4000 System Boiler provides efficient and consistent heating throughout the home. Advanced condensing technology and a wide modulation range automatically adjust the boiler's output to match demand, helping reduce gas consumption while maintaining comfortable indoor temperatures and lower energy bills.

Compact Contemporary Design

Designed to fit neatly into kitchens, utility rooms, or airing cupboards, the Greenstar 4000 combines premium styling with excellent installation flexibility.

Dimensions

• Height: 724mm
• Width: 400mm
• Depth: 310mm

The included horizontal flue and 15mm Scale Reducer provide a complete installation package while helping ensure reliable long-term system performance.

Advanced Energy Efficiency

Rated ErP A with up to 94% central heating efficiency, the Greenstar 4000 uses advanced condensing technology to maximise heat recovery while reducing fuel consumption.

Its intelligent modulation adjusts heating output according to demand, improving efficiency and helping homeowners reduce running costs without compromising comfort.

Smart Heating Control Compatibility

The Greenstar 4000 is fully compatible with Worcester Bosch EasyControl, allowing homeowners to control heating schedules remotely via smartphone or tablet. It is also compatible with solar thermal systems, providing greater flexibility for future renewable heating upgrades.

Reliable Performance & Easy Maintenance

Built to Worcester Bosch's renowned quality standards, the Greenstar 4000 features durable internal components, Quiet Mark certified operation, and a clear full-colour display for simple monitoring and control.

Its installer-friendly design with front-access servicing simplifies installation and ongoing maintenance, helping reduce servicing time and improve long-term reliability.

Warranty & Peace of Mind

The Worcester Bosch Greenstar 4000 18kW System Boiler Including Flue & 15mm Scale Reducer includes up to a 10-Year manufacturer's warranty when installed and registered in accordance with Worcester Bosch's qualifying warranty conditions, providing long-term confidence and dependable after-sales support.

Why Choose the Worcester Bosch Greenstar 4000 18kW System Boiler Including Flue & 15mm Scale Reducer?

• Premium Worcester Bosch system boiler
• 18kW heating output
• Includes Horizontal Flue
• Includes 15mm Scale Reducer
• Designed for sealed heating systems
• Up to 94% central heating efficiency
• Quiet Mark certified
• EasyControl compatible
• Solar compatible
• Up to 10-Year manufacturer's warranty