[Skip to main content] [Skip to secondary navigation] [Skip to accessibility information]

Greenstar Heatslave 18/25

image of Greenstar Heatslave 18/25See how the Greenstar Heatslave reduced this homeowner's fuel bills - Worcester Energy Houses

5 year warranty logo Free 5 year oil-fired boiler warranty. Find out more…



The Greenstar Heatslave series is part of a market-leading range of energy-saving condensing oil-fired boilers from Worcester. At least 90% of the oil consumed by a Greenstar Heatslave condensing combi boiler is converted into heat for the heating and/or hot water system and they can cut heating and hot water bills by between 5-10%.

Greenstar condensing boilers deliver this energy-saving performance by recycling exhaust gases to extract and re-use latent heat - a highly efficient use of energy which also significantly reduces carbon dioxide in the atmosphere.

  • SEDBUK* A Rated – environmentally friendly
  • Pre-heated thermal store – instantly heated hot water
  • Optional fascia mounted programmer – reduced wiring
  • 18kW, 25kW and 32kW DHW (domestic hot water) and CH (central heating)
  • 5 year** warranty
  • Robust quality manufacture – quality assurance

    *Seasonal Efficiency of Domestic Boilers in the UK
    **Subject to conditions

Home | Head office contacts | Sitemap | Enquiry form | Accessibility |