Practical guide on how to vent your radiator and why it’s important.

If you own a radiator that is cold at the top and hot at the bottom, it is likely that your radiator needs venting (bleeding).

Pockets of oxygen naturally build up in central heating systems due to the amount of fresh water running through it - this in turn causes radiators to become less efficient. Radiators require venting to alleviate the build up of air, which in most cases is a manual process.

How to Vent/Bleed your radiator:


-Take care to protect decorated surfaces with a cloth or small bowl to catch the water prior to opening the air vent.


- Venting is best carried out when the system is cold, to do so, simply turn off the heating system and slightly open the air vent (some radiators will require a radiator vent key, others may need a small screwdriver) until water is noted at the air vent (this means all air has been purged from the radiator)


- Gently close the vent and then switch the system back on.


If the radiators need venting frequently, there may be a fault with the system and a heating engineer should be called.

If the pressure should be lower, it is necessary to restore the correct operating pressure by turning the appropriate knob in the boiler itself.
After having vented the radiators, it is necessary to check the water pressure of the radiators through the pressure gauge of the boiler whose dart must be positioned between the value 1 and the value 2.

At this point, simply restart the system by turning the boiler or circulation pump back on and check that the radiators heat evenly.

 If not, it means that there is still too much air inside and it will be necessary to repeat the operation.