How to Bleed Radiators

When your heating system has a lot of trapped air inside it, it can cause it to work less efficiently. Bleeding your radiators can help to release this excess air, ensuring your home’s central heating is more efficient and that you are using the right amount of energy.

How to bleed a radiator

To start, ensure that your boiler and central heating are switched off (don’t try and bleed a radiator while the boiler is on). You should also have a clean cloth ready for use.

Place a cloth or rag under the valve on the radiator you are bleeding to catch any drips of water that might come out as the air escapes from the radiator.

Next, place the radiator key into the square part of the bleed valve and turn it counterclockwise about half a turn to allow trapped air to escape from your radiator. As soon as you hear the hissing sound from the air escaping, you should begin to see water starting to spill out of the radiator and into your bucket.

Once the hissing stops and you’ve seen a steady stream of water leaking out of your radiator, you are done! You can then close the bleed valve and move onto the next radiator.

How to bleed hot water radiators

A hot water radiator is part of your home’s hot water heating system and is made from a metal panel. It is often fitted with two pipes coming into it. Identify which type of radiator you have by checking its shape and whether there is an air vent sticking out of the side. If your radiator has a single pipe and an air vent sticking out of the side, then it is most likely a steam-based radiator.

If you’re unsure which type of radiator you have, ask a professional.

To bleed a hot water radiator, you need to first make sure that the heating is off and that you’ve laid down towels on any floors that might be affected by water spillage. You can then begin by bleeding the radiator that is closest to your boiler, working your way through to the others.

When you have finished bleeding all the radiators on the lowest floor of your home, move up a floor and repeat the process. This is a good time to check that all the other radiators have been bled and are running correctly.

You can also bleed steam-based radiators, but you will need to contact your local expert to do this.

During this process, be aware of the risk of scalding as the water might spray out of your radiator. You should avoid getting in too close to the area as hot water may splash up and scald you.

Once you have completed bleeding all the radiators in your home, turn on your central heating. Give each radiator a few minutes to heat up and to get up to temperature before you turn it off. Afterward, be sure to check all of the radiators again to ensure that they are evenly warm throughout the whole surface area of each one.