Survey
2
Choose
3
Customise
4
Book
5
Complete
Step 2 of 5Choose
?
View more boilers

Choose Your Boiler

Need some advice
1
2
3
4
Worcester Bosch Greenstar 4000 18kW System Flat Total Home Bundle – IF4

Worcester Bosch 4000 18kw Total Home Bundle

SKU: 120-1201-21-04

£4,213.00

MSRP:

Starting from £4,213.00
Instant Advice Options
What's Included
An ultra-quiet and reliable system boiler, ideal for small homes. Part of the award-winning Greenstar range, it features a modern design and simple controls. Enjoy lasting warmth and comfort with a 10-year guarantee.
  • With an ERP rating of A and efficiency of 94%
  • Central heating output of 18kW
  • Worcester Bosch boilers rated 4.7 on Trustpilot
  • WarmZilla is a trusted Worcester Bosch Installer
GET QUOTE

We offer fast and reliable boiler installations within 48 hours.

Every one of our engineers are Gas-Safe Registered.

We cover every UK postcode.

Rated Excellent on Trustpilot.

Don't Just Take Our Word For It: See Why UK Homeowners Trust WarmZilla!

Partner of CompareTheMarket & MoneySuperMarket

Trust Pilot Star

Rated Excellent on Truspilot

Trusted Partner of Checkatrade

The Worcester Bosch Greenstar 4000 18kW is a high-efficiency system boiler ideal for medium-sized homes that need reliable heating and hot water performance. Combining Worcester Bosch’s trusted engineering with modern efficiency, it provides consistent warmth, low running costs, and long-term dependability.

Its sleek, compact design allows for flexible installation, fitting neatly into kitchens, airing cupboards, or utility areas. The Quiet Mark certification guarantees near-silent operation, while built-in frost protection ensures year-round reliability, even in colder conditions. With its A-rated efficiency, it helps reduce energy use and supports more sustainable home heating.

Backed by a 10-year parts and labour guarantee, the Greenstar 4000 18kW offers lasting peace of mind and excellent performance. For homeowners seeking a quiet, efficient, and durable heating solution from one of the UK’s leading boiler brands, the Worcester Bosch Greenstar 4000 18kW is a perfect choice.

We offer fast and reliable boiler installations within 48 hours.

We cover every UK postcode.

Trustpilot
kW Output
18 KW
ERP Rating
A Rated
Energy Efficiency
94 %
Dimensions
Height 710mm
Width 400mm
Depth 310mm
10 year guarantee
Manufactured in the UK
High performance, control and efficiency
Precision heating to reduce your fuel bills
Perfect for small to medium sized homes with one bathroom
Worcester Bosch boilers rated 4.7 on Trustpilot
Heating technology at it's best
Rewire Current Thermostat
Hive Smart MINI Heating Wireless Thermostat - Battery FREE
Adey MagnaCleanse - FREE
Adey MagnaScale 2 Scale Reducer 15mm FREE
Installation by a local Gas Safe Engineer (arriving between 8-11am)
Removal of existing system (inclusive of tanks if applicable)
Removal of installation rubbish off site including boiler
Boiler flue installation
Magnetic filter for ongoing protection
System cleanse of your heating system
Inhibitor and System cleaner for protection
Condensate pipework or upgrade (if applicable)
Gas pipe upgrade (if required)
Copper and fittings pack with pipe work installation
Re-wire of existing controls
CO Alarm included
Delivery of package via courier or your local engineer
12-month WarmZilla workmanship warranty
Registration of warranty and Building Control Certificate by WarmZilla
Warranty includes parts and labour free via the manufacturer
Full protection of property, surfaces, and workspace throughout installation
Handover of your new boiler, including control panel and pressure top-up guide
Removal of redundant pipework and accessories (where necessary)
Removal of any old or unused controls (if applicable)
Sealing of external flue and condensate pipework to the building fabric
Making good of any brickwork around the flue exit
Commissioning of your new boiler for full operation
Balancing of your heating system (if required)
Final tidy-up and removal of all protective coverings
£4,213.00 inc.VAT Fixed Quote