Worcester Greenstar 4000 12 System Boiler

The Worcester Greenstar 4000 12kW System Boiler is a highly efficient, reliable, and compact heating solution designed for small homes with a stored hot water system. As part of the popular Greenstar 4000 range, this model delivers excellent performance, quiet operation, and industry-leading energy efficiency, making it an ideal upgrade for older system boilers.

Working with an existing hot water cylinder, the 4000 12kW provides consistent, reliable heating while keeping running costs low. Its modern design, advanced digital controls, and cupboard-fit size make installation simple and suitable for most home layouts.

Key Features

• 12kW system boiler ideal for small properties

• Designed to work with a hot water cylinder

• A-rated efficiency for reduced energy bills

• Modern digital interface with clear, intuitive control

• Quiet operation, suitable for installation in living spaces

• Compact cupboard-fit design

• Compatible with Worcester Bosch smart controls

• Excellent reliability backed by Worcester Bosch engineering

Suitable For

• 1–2 bedroom homes

• Homes with a hot water cylinder

• Small heating systems with low–moderate demand

• Replacing older system boilers with minimal disruption

Installation Note

To ensure safe operation and maintain the manufacturer warranty, the Worcester Greenstar 4000 12kW System Boiler must be installed and commissioned by a Gas Safe registered engineer.