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How to bleed radiators

//How to bleed radiators

Bleed radiators and why it’s important

Every household needs to bleed their radiators to keep the heating system efficient and energy bills low.

If the top half of your radiator feels colder than the bottom half or the whole radiator is cold, it means that air trapped in your heating system. Trapped air will displace the hot water in radiators and decrease the heat that is released from them, as well as increase your energy bills. We have prepared this step by step guide to help you understand how to bleed radiators.

When do I need to bleed radiators?                                                                                                                                                                bleeding radiators  

Switch on your heating system and check all the radiators individually. If

  • Radiators are taking too long to heat up
  • Radiators not heating up
  • Radiators are cold at the top

This will help you identify which radiator needs bleeding.

Bleeding radiators Order

You should start bleeding your radiators from the ground floor of your home. It is also recommended to first bleed radiators that are furthest away from the boiler.

Bleeding radiators Hot or Cold

Your heating system should be completely switched off before you start this process. The radiators should be cool before you start bleeding your radiators.

Bleeding radiators key  

You will need a special designed key to bleed radiatorsbleed radiators

This key will open the small valve at the top end of your radiator (could be on either side of the radiator). You can also use a small wrench or any other tool that fits the vale on your radiator or get the key from local DIY.

How to bleed a radiator

  1. Switch off your heating system .
  2. Get a small cup, cloth and radiator key.
  3. Open the ‘Bleed screw’ at the top on either side of your radiator with the help of the key. If gas is escaping from the radiator you will hear a hissing sound. Keep the cup under the screw for waste water.
  4. When there’s no more hissing sound, water will escape and you need to close the valve quickly.
  5. Check the boiler pressure from the gauge on your boiler. If the boiler pressure is low, you will need to top up. You can do this by using the filing loop situated normally under the boiler.

Once you complete all these steps, Switch on your heating system and check your radiators to see if they are performing better, if the problem still exists, fill out our quick form for boiler repair quotes from local engineers.

Get Boiler replacement quotes from local gas safe engineers. Use our free no-obligation service to save money on new boiler cost.