Agile, I of course realise fault finding on boilers requires technical skill, i thought thats why this forum was here, so that technically minded people/ engineers could help the layman to trace and maybe in some cases repair their own faults. the majority of us are not idiots and with some helpful replies could possibly understand and learn some basic faulting proceedures. Your last post seemed a bit "smug", not particularly constructive. Perhaps if you explained how a thermal survey was carried out, and what you mean by "basic test equipment" i might get somewhere. 
