I recently had a plumber replace a shower mixing valve in my bathroom and he turned off the water supply to the house and then turned on the shower mixing valve to drain any water and pressure that was in the system prior to changing the shower mixing valve. After the new shower mixing valve was installed he turned the water supply to the house back on to check for leaks. The new mixing valve leak checked good and the plumber was paid and left. However, that night I noticed I no longer have hot water. It still gets slightly warm, but not hot. After reading some forums I'm starting to wonder if maybe the top element in my water heater burnt out when he drained the system of water of pressure to change the mixing valve? Any thoughts would be greatly appreciated in regard to if this is possible?

The valve probably has a device that limits the hot water. Read the directions.

I'm guessing the hot water works fine everywhere else ?
I also think it's the temperature limit device under the handle that needs to be adjusted.

IT is VERY hard to drain the water out of a water heater accidentally, so that is not likely to be the problem, but without more testing we cannot tell you what the problem REALLY is.

Ok, I learned a lot about water heaters today. I initially thought one of my heater elements had gone bad since I was still able to get luke warm water but after disconnecting power and draining the system and disconnecting wires to both heating elements I found that the new element and the original two elements all ohm checked the same. A visual exam showed minor buildup on the elements but I'm guessing that is probably normal. Based on those findings I determined it was probably one of the thermostats that had gone bad and bought electric water heater tune-up kit which consisted of two new probes and a new upper and lower thermostat. After I replaced those items the electric water heater works as advertised and we have hot water again. Thanks for all your help and I would still be interested to know if thermostats typically go bad. After learning about the system it appears to me as a newbie that elements would generally be the part in the system that would fail and not the thermostats. Any input or experience would be greatly appreciated for my own knowledge...thanks in advance.



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There are a number of factors that contribute to the life of a water heater. The water quality and the temperature setting play the largest part. If a person with hard water has the heat set high, it tends to destroy elements faster, and if the tank isn't drained regularly, it will build up sediment. If the sediment reaches the lower element it will burn out very, very fast. If a person does have hard water, but cleans the sediment out regularly, and keeps the temperature down a bit, it will tend to wear out upper thermostats before elements in my experience.

In 65+ years, I MAY have replaced a dozen thermostats, or so, so NO they do not go back frequentily.

I have changed 4 in the last 3 years. One of the heaters wasn't even a year old. I think part of the problem is cheap, low quality parts.