if it works again observe it for noises. They generally do not trip for no reason but can for minor troubles so observe and switch off by thermostat if anything concerns you
iain
June 2008
They do not: if nothing is happening try pulling front lower panel off, grey one around thermostat. there is a red reset button in there, looks like red cross try pushing that in to see if for some reason the boiler has tripped its overheat stat