I have a gravity fed boiler, which self fills when bleed. I have an airlock which shifts from one radiator to another, just wondered if bleeding whilst running, may help? I can’t get rid of the air? New boiler, new pump.
Better really to do it with the boiler running, as the pressure will be there, to force any air out better, just be careful when the water starts to spurt out of the bleed vavle, make sure you have a cloth under it to catch any water that comes out.