I'm recently having trouble with a water heater. The pilot light with ignite just fine, but will go out after releasing the reset button, even after holding it for over a minute. That makes me think the thermocouple is bad.
In addition to that, the hole where the brass nut that holds the thermocouple in place is stripped out. I cannot get the nut into the hole. I tried holding the thermocouple in place with my hands and also with strands of duct tape and the pilot would still not stay lit.
But would the pilot stay lit if the bolt were not in place, or does the bolt serve a purpose other than securing the thermocouple that allows it to function?
Best Answer
To be clear for future searchers: the nut is critical, it provides half of the electrical connection.
A thermocouple requires two wires to function: electricity is generated at the junction of two different metals and two wires are needed for current to flow. While some thermocouples have two wires, the original poster is talking about a model with one wire. The case of the thermocouple must firmly contact the frame of the furnace, to complete the circuit. Consider buffing the furnace frame with steel wool to remove rust and scale.