Every radiator in your home should be hot from top to bottom. If they're hot on the bottom and cold at the top, there is air trapped inside. When this happens, you'll need to bleed them.

Bleeding radiators is important. It will make your home warmer and might also reduce the cost of your energy bills.


Video: How to bleed your radiator


Step-by-step: How to bleed your radiator

You'll need to use a radiator bleeding key, which you can buy online or in DIY stores. You'll also need a cloth to catch water.

Make sure you read through all the instructions and before following them step-by-step.

  1. Make sure your heating is off and the radiators are cold. It's important that you do this to keep yourself safe. If the radiators are on, or they're still warm, hot water will leak out and this might cause burns.
  2. Find the bleed valve, hold a cloth underneath, and insert the bleed key.
  3. To open the valve, turn the key anti-clockwise until you hear air escaping. This will sound like a quiet hissing noise and is normal.
  4. When the hissing noise stops, some drops of water will leak out. The air is now gone from the radiator. You'll need to turn the key clockwise to close the valve.
  5. Repeat the same steps on every radiator that needs bleeding.
  6. Turn your heating on and check your radiators are now heating up from top to bottom again.
  7. Check your boiler pressure to see if it's lowered. If so, you'll need to top it up which is easy to do. If you're not sure how to do this, you can watch our video on how to top up your boiler pressure.


If you have any questions or don't feel confident doing this by yourself, please get in touch with us. We're happy to help.

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