Bleeding your radiators is a straightforward task, completed when your heating is turned off, that can help to improve energy efficiency and keep bills down this winter. You can follow our top tips and the step by step guide below or download our guide at the bottom of this page.

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Where to start?

There are 2 types of heating system: sealed and open. Sealed systems can be identified as they have a pressure gauge on the boiler. Open systems have a feed and expansion water tank in the loft. There are normally 2 water tanks: one large one and one small one. It is important to know which system you have before bleeding your radiators as the process for each is slightly different.


  • Use an old rag or paper towel when bleeding air, as a small amount of dirty water may appear 
  • Put a small towel or cloth on the floor below the radiator to catch any drips you miss
  • You do not need to remove the bleed vent, just open it as much as needed so it can be closed quickly when water appears
  • If your boiler has a water pressure indicator, you may need to top up the water pressure during and after the bleeding process
  • Boilers with a water pressure gauge have a visible red pointer showing the cold water pressure set point
  • If you are unsure of what to do or if there is an problem with your heating system then contact a heating engineer who will be able to help

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Radiator Bleeding Guide #LoveYourRadiator