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Worcester Greenstar 25si Compact (ErP) Combi Boiler, Standard Flue and Clock Kit

(2 reviews)

£1,253.23 £1,044.36

The Greenstar 25Si Compact condensing combi boiler kit is Worcester's lowest output mid-range appliance, suitable for apartments and small to medium-sized properties with one bathroom. It enables you to control both the hot water and central heating temperatures, while a range of optional controls offer you further comfort and flexibility.

  • Keep hot facility for instantly heated hot water
  • Compact dimensions save space and allow flexible siting
  • Smart looking and simple to use
  • Environmentally friendly with low NOx and CO2 emissions
  • Which? Best Buy accreditation
  • Kit comes complete with a standard horizontal flue and a time clock
Worcester Bosch
Manufacturer Product Number
Not Applicable
Manufacturers Warranty
5 Years (Subject to Manufacturers T&C's)
Mr CH's Warranty advice
Warranty Terms and Conditions
Boiler Type
Combination Boiler
Kit Contains
Boiler, Clock and Flue
Fuel Used
Natural Gas
Boiler Height
Boiler Width
Boiler Depth
Boiler CH Output (Kw)
Max DHW Output (Kw)
Boiler CH Output (BTU)
Domestic hot water flow rate
10.2L @ 40C Rise
Energy Efficiency
ErP Hot Water Rating
A Rated for Hot Water
ErP Heating Rating
A Rated for Heating
Customer Questions
How can I work out what boiler I need?

<h3>Finding out what boiler you need is a serious question.</h3> <p>To answer this question it deserves a little more attention than an FAQ section can provide. That's why we have created our <a href="" title="Find a Boiler" target="_self">Find a Boiler </a>tool.</p> <p>Just follow the easy to use steps and we will show you the options that best suit your needs.</p>

Are your products guaranteed?

<h3>Yes all our products come with a guarantee.</h3> <p>Guarantees or warranties vary, by product and manufacturer.</p> <p>All our products are guaranteed for a minimum of 1 year (radiators 10 years, copper tube 25 years) but many offer longer warranties from the manufacturer, which you may need to register for.</p> <p>On each product, under the specification tab, you will find more information on the guarantee or Warranty.</p> <p>Follow links through to various manufacturers sites, as each manufacturer will have its own terms and conditions for qualifying for longer warranties.</p> <p>You do not want to miss out by getting the wrong installer for some boilers etc.</p> <p>As Boilers and radiators are installed by third parties, they do have to install in compliance with regulations and manufacturer standards to get the full benefit of the warranty.</p> <p>As long as these ar fulfilled, you will get the maximum life and support from your new purchase.</p>

What kilowatt rating do I need for an 8 radiator household for a combination boiler?

<p>To calculate the size of boiler, you need to answer a few questions.</p> <p>The easier method would be to use our <a href="" title="Boiler finder tool" target="_self">Boiler finder</a> tool.</p> <p>Just follow the on screen prompts and this will filter down to the best choice of boilers for your needs.</p>

Please, mind that only logged in users can submit questions
1 x Worcester Greenstar 25si Compact (ErP) Combi Boiler Only   + £1,117.87 £931.56
1 x Worcester Telescopic 350 mm - 570 mm Horizontal Flue Kit   + £83.47 £69.56
1 x Worcester Mechanical Timer MT10   + £51.89 £43.24

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Package Deal Summary Worcester Greenstar 25si Compact (ErP) Combi Boiler, Standard Flue and Clock Kit

    £1,253.23 £1,044.36

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