Worcester Bosch Greenstar 4000 System Boiler Review

Worcester Bosch Boilers

As one of the world's leading names in heating innovation, Worcester Bosch, founded in 1962, is synonymous with customer satisfaction.

Blending high end technology with assured traditional engineering, has made the brand one of Europe's most trusted boiler manufacturers.

Worcester Bosch Greenstar System Boiler Range

The Worcester Bosch Greenstar 4000 has been created to follow the form of the extremely popular original Greenstar branch of the Worcester Bosch range.

Combining the latest in heating design and energy efficient application, the Greenstar hallmark represents a modern icon of the boiler industry.

Worcester Bosch Greenstar 4000 System Technical Specifications

Worcester Bosch Greenstar 4000 Key Components And Features - 

• Full back lit colour LCD display

• Wide power range to reduce gas consumption and lower energy bills

• Compatible with unvented indirect cylinders and twin coil cylinders for solar synchronisation

• Our quietest system boiler

• Features wireless connectivity with Bosch EasyControl

• Can be used with Greenskies solar panels for energy and cost savings

Smart Thermostat

The Greenstar 4000 system is fully compatible with smart thermostats like the Worcester Bosch EasyControl system.

This means thanks to the brainy bunch who manufactured your new boiler, it can be easily controlled at the touch of a button for rapid regulation and optimisation.

Eco Friendly 

Our Greenstar system boilers are compatible with Worcester Greenskies solar panels, a clean alternative energy source that reduces carbon emissions and saves money.

Also due to their energy efficient multiple outlet capabilities at one time, system set ups are considered more eco-friendly.

What Is A System Boiler?

A system boiler links with a hot water storage cylinder to provide a home with central heating and hot water. It does this by taking cold water directly from the mains (instead of a cold water storage tank) and heating it via an internal heat exchanger, this transfers gas energy to water.

The hot water is then moved to the hot water cylinder for storage.

Unlike some regular boilers, such as oil or heat only, that use bulky external components, with a system boiler the majority of components are integrated within the appliance.

The only external part is the aforementioned hot water storage cylinder; This is a much smaller unit than some of the other hot water storage tank systems used by regular boilers, these tend to eat up an excessive amount of loft space.

However if you think your property is more suited to a combi, check out our handy guide to the best combis of 2026 right here!

How Much Does The Worcester Bosch Greenstar 4000 Cost?

Our prices for the Greenstar 4000 system (installation included) start from

15kW - £2,460 Get a quote

18kW - £2,509 Get a quote

21kW - £2,523 Get a quote

Overall the Greenstar 4000 system boiler continues the long line of Worcester Bosch quality home heating, and would be a great option for small to medium sized properties with a high water demand, especially in its larger kW sizes.

If You need some quick info on the Worcester Bosch Greenstar 4000 System Boiler, check out the handy boiler manual PDF!

Need A New Boiler?

Here at iHeat, we want our customers to receive only the highest quality heating systems, that's why we stock a wide range of Worcester Bosch Greenstar boilers. Get a free fixed price quote online today or get in touch for any enquiries!