The water heater is finally working again.
No, you haven't missed any earlier articles about the problem. I've been pretty busy of late, as this came to light as I was getting ready to go back to work.
We have an all electric house, so (of course) our water heater is electric. Years ago we replaced a standard unit with a non-metallic one, as that keeps the sulphur bacteria from growing in the tank. I like that choice, but may get a tankless unit later. Time will tell.
In any event, things got interesting with the water heater a couple of weeks ago. It stopped producing hot water, and eventually I found that it was tripping the circuit breaker at odd intervals.
Eventually I determined that one thermostat was bad, as it was only passing 120 volts (instead of 240) to the lower heating element. I ordered replacement thermostats - both upper and lower - installed them, and found that didn't solve things. Additional research convinced me that the lower heating element was also bad and shorting out. Then my friend Alan figured out that the new upper thermostat I'd been sent was bad too.
While I waited for parts to arrive I disconnected the lower heating element to avoid the short, used one of the broken upper thermostats, and turned the water heater on with the circuit breaker only when we needed it. That wasn't exactly an approved - or convenient - solution, but it worked. Thankfully we didn't have to do it for long.
In the end - two heating elements and a replacement for the replacement thermostat later - I've finally got it working properly. It turns out the lower heating element had corroded to the point that it had sheared off entirely inside the tank. That caused the short that tripped the breaker, so all the obvious failures are explained now.
A less than obvious thing is also explained. For some time we had a lot of air in the hot water lines. I couldn't figure out why that was, but now I know that the broken heating element was turning water into hydrogen and oxygen gas right there inside the tank. Exciting, eh?
At this point I can assure you that a functioning water heater is a very good thing, and I'm glad to finally have one again.