Worcester Greenstar 4000 18KW System Boiler

Worcester Greenstar 4000 18kW System Boiler

The Worcester Greenstar 4000 18KW System Boiler is a practical choice for customers comparing system boilers, offering dependable heating performance for homes with a separate hot water cylinder. If you are reviewing system boiler prices, this Worcester Bosch model gives you a clear option to compare by output, fuel type, controls and installation requirements before choosing the right boiler for your property. The Worcester Greenstar 4000 18kW System Boiler is a reliable, energy-efficient choice for medium to large-sized homes, especially those using a stored hot water cylinder. Designed with modern households in mind, it offers excellent performance, quiet operation, and the flexibility to pair with a wide range of heating controls. Its compact and lightweight design makes installation straightforward, even in tighter spaces. With built-in components such as a pump and expansion vessel, it reduces installation time and creates a tidy, streamlined setup. Homeowners can also enhance comfort and efficiency by adding optional controls, including smart thermostats.

Key Features

• Compact, space-saving boiler ideal for flexible installation
• Built-in pump and expansion vessel for a cleaner, faster setup
• Compatible with optional plug-in diverter valve
• Wide choice of optional heating controls
• Perfect for homes using a stored hot water cylinder

Technical Information

Manufacturer: Worcester Bosch Model: 4000 MPN: 7733600381 SKU: 79144 GTIN: 4057749856708 Product Type: Gas System Boiler Performance: CH Output: 18kW CH Output (BTU): 61,000 ErP Rating: A Rated for Heating Dimensions: Height: 724mm Width: 400mm Depth: 310mm Weight: Gross Weight: 33.2kg Warranty: 7 Years (Manufacturer T&Cs apply)

FAQs

Is this boiler suitable for larger homes?

Yes - the 18kW output makes it a strong fit for medium to large homes , especially properties with multiple radiators and a stored hot water cylinder.

Do I need a hot water tank with this system boiler?

Yes. As a system boiler , it works alongside a stored hot water cylinder, but it does not require a separate feed tank like a conventional boiler.

Can I use smart controls with this model?

Absolutely. The Greenstar 4000 range supports a variety of optional and smart controls , helping to improve comfort and boost energy efficiency.

Check out our full range of plumbing supplies.

Browse more boilers available online.

At JJ Building Materials, we're committed to supplying quality building products at competitive prices, backed by the service and expertise you'd expect from an established independent merchant. Whether you're a trade professional managing large-scale projects or a homeowner taking on a DIY renovation, we're here to help you find the right products for the job.

As part of the JJ Roofing Supplies Group, we build on decades of experience supplying construction materials across the UK. We've expanded beyond roofing to offer a growing range of building materials, including timber, insulation, landscaping products, plumbing supplies, flooring, doors, bricks, fencing, garden buildings and much more – all available to order online with nationwide delivery.

We work with many of the industry's leading manufacturers to bring you trusted products that meet the highest standards of quality and performance. Our team is passionate about providing excellent customer service, competitive pricing and a straightforward shopping experience from start to finish.

When you shop with JJ Building Materials, you can expect:

• Competitive prices on leading brands and quality products.
• Nationwide delivery across the UK
  
• A constantly expanding range of building and landscaping materials.
  
• Friendly, knowledgeable customer support.
  
• A trusted business backed by the JJ Roofing Supplies Group.
  

Every order is personally reviewed by our experienced team to ensure everything is correct before dispatch. We offer delivery from as little as the next working day on selected products, so please refer to the dark blue Estimated Delivery box above for the expected delivery timeframe for this item.

We work with trusted manufacturers and specialist delivery partners to ensure your order arrives safely and on time. You'll receive tracking details once your order has been dispatched, and if we need to confirm any delivery details, one of our team will contact you directly to keep everything running smoothly.

Roof Tiles & Fittings:

We recommend ordering an additional 10% of roof tiles to allow for any breakages that may occur during delivery or handling. Roof tiles are naturally fragile, and having a few extra on site helps prevent delays and ensures your roofing project can be completed without interruption.