Worcester Bosch Greenstar 4000 25kW Combi Boiler

Greenstar 4000 25kW Combi Boiler
Total Cost
£2,000 - £2,500
Manufacturer Worcester Bosch
Boiler Model Greenstar 4000 25kW Combi Boiler
Condensing boiler? Yes
Energy Efficiency Rating 94%
Energy Band A Rating
LPG model/Conversion kit Available soon
Manufacturer Warranty Up to 10 years
Heating Output 24 kW
Wall Mounted or Floor Standing Wall-mounted
DHW Flow Rate 10.2 l/min
Total Cost £2,000 - £2,500
ERP Rating A HEAT A WATER
Hot Water Max Output 25 kW

Worcester Greenstar 4000 25kW Overview

The Worcester Greenstar 4000 25kW builds upon the proven features of the Greenstar i series while introducing significant advancements in appearance, performance, and installer convenience. 

In our Worcester Boiler overview at boiler central, learn more about This model, specifically designed for 25kW output, offers enhanced installation speed, commissioning efficiency, and servicing convenience, along with notable improvements in efficiency and control.

Drawing inspiration from Worcester’s top-tier 8000 Style and informed by installer insights, the Greenstar 4000 delivers real advances in siting flexibility, transforming the nation’s favourite boiler into an even more impressive heating solution.

Standard Guarantee

  • 7-Year Guarantee: Included with any Greenstar System Filter
  • 8-Year Guarantee: Available with any Greenstar System Filter for an additional £40 (Non-WAI Excelerate members only)*
  • 10-Year Guarantee: Exclusive to Accelerate members, or available to Non-WAI’s with an extra payment of £40. Terms and conditions apply.

Features & Benefits

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100% Planet-Friendly Packaging

 Demonstrating Worcester’s commitment to sustainability, the Greenstar 4000 comes in environmentally conscious packaging.

Front Access to Key Components 

Simplifying servicing, all key components are readily accessible from the front of the boiler.

Longer Flue Lengths

 The boiler accommodates flue lengths up to 12m (60/100), providing greater installation flexibility.

Intuitive Full-Color Long-Text Display

 Users benefit from an easy-to-navigate display, offering comprehensive information and control options.

500ml Condensate Syphon

 Ensures efficient condensate disposal, enhancing the overall performance of the system.

Quiet Operation

 Operating at a mere 45dB(A), the Greenstar 4000 provides quiet and unobtrusive heating.

Compatible with Greenstar Intelligent Filling System

 Seamlessly integrates with Worcester’s intelligent filling system for optimised performance.

Modulation Down to 3kW Central Heating Output (1:10)

Allows for precise control and energy-efficient operation, ensuring optimal comfort and savings.

Increased DHW Efficiency

 The boiler improves DHW efficiency while minimising waste water, promoting eco-friendly practices.

Is the Worcester Greenstar 4000 25Kw worth it?

When thinking about a new boiler replacement, the Worcester Greenstar 4000 boilers provide an excellent choice for those looking to enhance comfort and reduce energy costs in their homes. Whether replacing an old, inefficient boiler or upgrading to a more reliable heating solution, Worcester Greenstar boilers offer peace of mind and long-term performance.

Is 25Kw enough to power my home?

When it comes to powering your boiler, consider factors like size of your home and the amount of radiators you have in the property. A larger home with more radiators may be better suited to a Greenstar 4000 30Kw boiler, so the boiler can keep up with the demands of the home.

Full flow Rates from 1 Bar Mains Pressure

Ensures consistent and reliable hot water supply even under varying pressure conditions.

The Worcester Greenstar 4000 25kW combines innovation, sustainability, and user-friendly design to provide a superior heating solution for modern homes. With its advanced features and extended guarantee options, it offers peace of mind and performance excellence to homeowners and installers alike.

Who are our fitters?

We use our own Gas Safe installers and the best installers the UK has to offer. Every single one is Gas Safe registered and has been thoroughly vetted.

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