Bleeding a radiator / air pressure

[xplosiv]

Hi All,

I'd like to try and bleed a radiator, but in an old post i seem to recall it was mentioned that after doing so with a sealed combi-boiler (which i believe i have), you'd need to change the air pressure.

Being a total novice with heating systems, I really don't want to get out of my depth and potentially mess up the heating - especially in the cold months. So, I just want to know

a) how do you know after bleeding if air pressure needs adjusting and how do you do that?

b) would be advisable to get an expert in to do this? would a heating contactor bleed radiators as part of a service on the heating system?

Thanks

 

[Breesey]

a) how do you know after bleeding if air pressure needs adjusting and how do you do that?

Check the pressure gauge on the boiler. It should be about 1 - 1.5 bar when the system is cold and off. If it has dropped you need to bring it up to this by carefully adding water via the filling loop (probably a wire braided hose, probably below the boiler somewhere).
Bleeding a radiator will reduce the system pressure so a little topping up is bound to be required.