I had something happen the other day that seems similar to this. My hot water was way hotter than normal, and I did not think much of it because I was so busy. Well today I find that I have no hot water. I was thinking that the upper limit needs reset, and that their is a bigger problem. After reading this I imagine that I have a leaking element that shorted out the limit and then the thermostat. I obviously won’t know until I open it tonight, but does this logic make sense to you experienced guys?