How to fix burnt water heater thermostat wire
Heat can cook the insulation off the internal wires connecting the upper and lower thermostats, making it impossible to route a replacement wire through the closed-cell foam insulation inside the tank shell. While running a temporary wire on the outside restores hot water, you need a safe and permanent way to route or splice the wire without paying for a professional repair.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Searching online for error codes and inspecting outdoor wiring
- 2Running the replacement wire temporarily on the outside of the water heater down to the lower thermostat
- 3Using a long drill bit from the top between the shell and the foam to drill a new channel for the wire
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“10 year old Bradford White blew the lower thermostat, heat cooked the insulation on the black wire coming from the top thermostat to the lower one right at the lower thermostat, cooked about 2-3 inches of insulation off.”source ↗
“I replaced the lower thermostat, but there is no way I can see to route a new black wire down. It looks like they used some sort of closed cell foam between tank and outer shell, so it is impossible to route wires down.”source ↗
“To get hot water again, I simply have the black wire temporarily running on the outside down to lower thermostat, but obviously would like a more code-compliant fix.”source ↗
“Is this something I can fix myself? If so, how? There is no way I can afford to have a company come out right now 😩”source ↗
Where this came up
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