My boilers overheating and switching off, a plumber in my local B&Q said it probably needs venting as there is likely a air block. where will i find the release valves? i know what it should look like but cant find it. i'm looking for the one off the hot water tank, this i belive is the source of my problem.
there should be two 22millimetre pipes entering the cylinder about a 3rd of the way up and the other just above. If you follow them pipes to the highest point there should be a bleed valve situated at the top of the pipe.