How to bleed a radiator

Are your radiators feeling cold at the top and hot at the bottom? Then you have air in your radiator. To solve this simply problem you will need to get yourself a radiator key from your local shop.  Many shops now stock these.

Radiator Key

If you have an open system, i.e. you have a heating water tank in your attic or similar place you will simply need to place the radiator key onto the bleeding vent and open the vent. At the start you will hear air coming out and then eventually water will come. When water comes out of the vent close it firmly.

TIP- It is always a good idea to carry an old cloth or tissue with you when bleeding a radiator as the water can be black and will stain carpets and walls. Use the old cloth or tissue to stop the water going onto the walls or carpet.

TIP-If the radiator key is a loose fit on the bleeding vent do not over force the key to open the vent if it is tight as this will deform the vent making it into a round shape. Instead go to your local plumbing suppliers or hardware shop and try an alternative key.

If you have a closed system, also known as a pressurised heating system you will need to top up the pressure after bleeding your radiator. To do this you will need to locate your pressure vessel. These are usually installed in your attic or beside your boiler. There will be a valve beside the vessel on a pipe the leads into the vessel. Open this valve and watch the pressure increase on the gauge. In most cases there will be a red marker on the gauge indicating the required pressure level. If there is not an indicator set the pressure to one and a half bar.

Pressure Vessel with valve to top up pressure