How to bleed a radiator

radiator key

How to bleed a radiator

Stand next a combi or system boiler and the first sound you should hear when the heating goes on is the sound of the mechanism heating the water as it flows through before pumping the hot water to through the pipes to the radiators. Sometimes the water does not distribute evenly through out the home or property and you may notice some radiators are warm whilst others are not.

This may be due to air trapped in the radiators. Below is a simple guide and video on how to empty the trapped air by bleeding the radiators.

Step by step guide to bleeding a radiator:

  • Firstly check that all the valves (Thermostatic radiator valve usually on the bottom of the radiators) are on; if they are off this will still stop hot water from flowing into the radiator.
  • Turn on the boiler.
  • Wait for about twenty and make a note of which radiators are not warming up.
  • Turn off the boiler completely and wait for a few hours to ensure all the hot water has cooled down.
  • Check the radiators to make sure none of them are warm.
  • Look at the boiler water level gage and make a note of the amount that is in the system; you will probably have to add more water to the boiler after you bleed the radiator(s).
  • Go back to the radiator(s) that was not heating when you first turned. It is recommended that if you have more than one radiator to bleed you start with the ground floor first furthest away from the boiler.
  • Look for the valve at the top of the radiator usually located at one end on the side.
  • With your radiator valve key and a large cup, put the key so that it fits over the square bolt, place the cup under the valve and slowly turn the valve.
  • You should hear the trapped air hissing out of the the radiator.
  • Next the water will start coming out this when you should quickly turn the valve off. You do not want to empty your heating system of water.
  • Once you have done this with all the radiators go back to the boiler check that how much water has left the boiler by looking at the gage from when you last checked.
  • Look at the water level as recommended by the boiler manufacturer and fill back to the level if necessary.
  • Turn the heating on and check to make sure all the radiators are at the required temperatures.

If after all your hard work the heating is still not working there may be another issue which should be diagnosed by a professional and Corgi gas heating engineer. Contact Humbrix below or go to the request form and we can see if we can help:

WhatsApp 07983872453