Is there a simple way to seal a small leak on a heating pipe?I have always wondered why I kept getting air gurgling around my heating system and have since noticed that there is a tiny leak around the nut that joins the radiator to the pipework,seems it just needs some PTFE tape added to it,but I am unable to get that done this winter so would just like to plug the hole and then blead the air out.System is a sealed heating system with combi boiler.Maybe some kind of spray?