Worcester Greenstar 4000 18kW System Boiler
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.
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