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How to Bleed a Radiator

By January 18, 2022January 25th, 2022Radiator Tips

If your radiator has cold spots or not heating properly then air is probably trapped inside and the radiator needs “bleeding.” Fortunately, bleeding your central heating radiators is a quick and easy process and can save you the headache from finding a plumber.

Here’s how you can bleed your radiators:


Step 1 – Identify cold radiators

You must first find out which radiators in your household has cold spots. You can check this easily by placing your hand around your radiator’s surface.


Step 2 – Find Bleed Valve and Key

Next, you will need to identify what valve your radiator has and find the right bleed key. This should be fairly easy unless you have a very special radiator model fitted in your home. The valve is usually in one of the top corners of your radiator (note: it might be on the back of the radiator!) There are different types of bleed keys, however for some valves you can use a flat headed screwdriver.



Bleed Keys:


Step 3 – Turn off Central Heating

Once you have identified which radiators need bleeding and found the right bleed key, turn off your central heating and let the radiator(s) go cold. This way you won’t burn yourself during the process.


Step 4 – Bleed

When your radiator has cooled down:

  • Hold a cloth or jug under the bleed valve
  • Insert bleed key
  • Turn bleed key anti-clockwise until you hear a hissing noise of air escaping
  • Wait until water starts coming out
  • Turn bleed key clockwise to close the bleed valve

Do these steps for all your radiators that have cold spots and once done, you can switch central heating back on. After a little while, come back to your radiator and check if temperature is now more even and that there’s no water leaking from the bleed valves.


Step 5 – Repeat Annually

Radiators should be bled at least once every year as part of routine maintenance in order to keep radiators working to their maximum performance.


This simple task will increase your radiator’s efficiency and soon your home will be a lot cosier and warmer.

If you can’t find the right key or don’t want to bleed your radiators yourself, you can always find a local plumber who can do this for you (for British Gas customers, this service can be £50 for all radiators)

Consider cleaning your radiator as well in order to maximise its efficiency and save even more on heating costs! Make sure you also keep plenty of space between your furniture and radiators to allow the circulation of warm air to continue. Note, curtains could also steal the emitted heat!


Energy prices are on the rise, the more efficient your radiators the less you pay and the warmer your home gets! Bleeding radiators is one of the easiest ways to avoid increasing your heating bills!

To find out more advice on how and which energy provider to use, we suggest who are Great Britain’s independent energy regulator.
If you want to compare your energy prices, check these comparison sites:


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