I have a glow worm fuel saver 25-30 boiler. I go away for a few weeks every summer and turn my gas off . Usually my boiler lights after a few attempts but not this time. The ignition lights the pilot light fine but even after holding the button in for about 3-4 mins the pilot light goes out. The light does not seem to "hit" the thermocouple "head on". it seems a little off centre. Would this be a possible problem? It has always lit in the past. Could I need a new thermocouple or is there a way to get it working better such as cleaning the tip etc ?