My mother-in-law called at 9:00 p.m. to tell us that she had no hot water. She said the temperature was between ice cold and luke warm.
Since they didn’t need the hot water last night and we visit each Sunday morning it was okay to wait until this morning to look at the problem. My husband and son measured the voltage to the water heater. There was no voltage. The breaker was popped, so they reset the breaker. It started working, but the old dirty contacts started glowing red melting the plastic thermostat housing. Over time dirt or oxidation gets in the thermostat and increases the resistance. It glows red because the contacts gets so hot and stays hot that they get stuck together and can’t turn the heating element back off. He knew from the glow that the thermostat was damaged. It took 5 minutes at most to locate the problem. He turned the breaker back off.
Off he went to Lowe’s and for $14 dollars he got an new thermostat. Since he was going out we hot White Castle coffee too. Yum!
He returned and put the new thermostat in in 5 minutes The water was hot before we were finished with our usual weekly visit.
This saved a service call at $75. Then they would have charged another $50 for the new thermostat and labor (this is a total guess as we have never had a service call). So $125 to do a 30 minute job including the trip to Lowes, which was most of the time involved.
Total savings: $125-14=$111.
My husband wanted to say that it is a good idea if you keep a spare thermostat and heating element about $25 (smaller units) or 2 thermostats and heating element $35 (larger units) and keep them handy you can do your own repairs anytime day or night without a trip to the home improvement store.