DrewE wrote:
If the thermocouple were not warm enough, wouldn't it shut off the pilot flame? I kind of thought that's how water heater controls usually worked, and that's why you have to hold the pilot light knob/button for a spell after first lighting the pilot. I may very well be mistaken, though.
It sounds to me more like a problem with the thermostatic gas control valve, maybe something sticking internally. If it were me, I'd probably chat with the clerk behind the counter at some local appliance repair place or gas company for their opinion given the symptoms.
I totally agree with your opinion because I am not sure neither how the thermocouple is working exactly in the overall operating sequence. But in my opinion it certainly have something to do with the burner control valve too (not only pilot), as you don't want your water heater burner to "switch on" gas if the pilot light have died! So the thermocouple surely have something to do directly with the burner control valve at some point. Are you not agree?
I do some searches on Google about this issue and I found two threads from other forum where people reported similar issue (where pilot light, but main burner won't turn ON) and they both finally pointed to a defective thermocouple/pilot assembly.
I also found a thread where the guy reported that the pilot light outlet where misaligned with the thermocouple rod and provide a bad heating. I am not sure exactly because it's a pretty tight space to look at, but maybe at some point my pilot outlet may been bend a little bit during the ignition process... I am trying to figure out what is the relation between the thermocouple and the main burner gas control valve here...
