Dying Hot Water Heater... Always On

My story is about an unknown increase of 75 watts in “Always On”. I got an alarm from Sense that the always on was higher than normal. My house usually has about 160 watts of Always On but now it was 235. Not a bad number but as an old industrial maintenance electrical engineer I know change can be a problem. I checked all the normal lights and flood lights I leave on and found nothing. After an hour of looking with almost nothing running in the house, I turned the electric hot water heater off. That was it! But how does a hot water heater draw only 75 watts? I had a hunch. Killed the power to the heater pulled the bottom cover and checked the status. All was dry, so not leakage. The resistance of the 4500-watt element is normally about 14 ohms, well today it was in the high kilohms. And that was my problem. The element had failed and we were getting hot water due to the top element taking the heating duty. During the failure we did not notice any problem. But sooner or later we would be out of hot water. Not a big deal unless you are all lathered up in the shower and the well water goes COLD!
We were going on a 2-week trip in a few days. The 75 watts of continuous input and no use for 14 days would have overheated the water. Hopefully the high temperature switch would have opened and prevented an over pressure of the heater and plumbing system. Sense helped me find the problem early and let me fix it on my time schedule. And prevented any possible catastrophic damage during our vacation. Thanks Sense.

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