One radiator in the house needs to be bled every week, it works fine otherwise and there is no sign of a leak near the radiator or in the pipes leading to it. Should I be worried about a leak?
Yes it's the towel rail in the bathroom upstairs. There is a layer of dust on the pipes around the relief valve so no dripping there. I've looked at all the pipes I can see, but some are underneath floorboards and fitted carpets upstairs!
Ok. Is this a new problem or being going on for some time? Are you sure its air and not hydrogen when you vent the radiator? Hydrogen will have a rotten eggy smell.