How to bleed your radiators for energy efficiency

bleeding radiator

Fix your heating problems with these 5 simple steps

Do your radiators remain cold even after turning your heating on? It may be time to bleed them. ‘Bleeding radiators’ is when you release the air that is trapped inside them, this improves the efficiency of your heating system. Without bleeding your radiators regularly, you will still be paying that dreaded energy bill but may not be feeling the benefits.

What tools do I need to bleed a radiator?

To bleed the air out of your radiators you will need:

1. A cloth/towel to catch the drips

2. A radiator bleed  key, this opens the radiator vent valve – releasing the air.

Here’s your guide to DIY radiator bleeding… Open each tab for more information.

Step 1: Turn your heating system on

Make sure all the radiators in your home are turned on, ensure they are all fully heated before moving onto step 2.

Step 2: Find which radiators need bleeding

Being careful not to burn yourself – feel along the top of each radiator for cold spots. Areas that are cold indicate trapped air and these are the ones that will need bleeding.

Step 3: Turn off the radiators

Turning off the radiators, and allowing them to cool will make it easier for you to bleed them without burning yourself or soaking your floor.

Step 4: Bleed the radiators

Hold a cloth under the valve to catch any water. Put the radiator key into the valve and turn until you can hear a hissing noise. When the noise stops and water begins to leak out, turn the key to tighten the valve again.

Step 5: Check the pressure

Once you have bled all of your radiators, you can check the pressure by looking at the gauge on your boiler. When bleeding a boiler heating system you will always lose a bit of water which can affect the efficiency of the heating system. If the pressure appears too low, you can top it up by using the lever or tap on your boiler, known as the ‘filling loop’. A normal pressure level for a domestic boiler should be between 1.0 and 1.5 bar.

That’s it! You have successfully bled your radiators. This should be done every few months to ensure you are getting the most out of your heating system.

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