Originally Posted by village dreamer View Post
sounds like your thermocouple has a thermal fuse. its made to burn out and stop main burner from coming on. sometimes water heaters,the inside vent line [shaped like a donut] will crush and wont vent the hot gass out and the main burner will come on and burn the thermal fuse. need new water heater.
Fortunately the OP heeded the advise on this forum and replaced the thermocouple which repaired his WH.
I have never heard of a thermal fuse on a gas WH. Neither has Google.
GAS WH not ELECTRIC
The part that showed damage on the thermocouple is shown on the following picture of the replacement Pilot assembly. The thermocouple is the copper colored line. That line has a round black item near bottom of picture connecting two parts of the thermocouple. One of the connector wires was unattached. I assumed it might be a resistor. Could have been damaged during removal but don't think so.
Amazon.com
So, if it is a thermal fuse, I guess it will fail again since the new part has the same item. We had no issue of excessively hot water prior to failure.