So i have been having trouble with my hot water heater....Its only 3 years old but for some reason every 2-3 days we only have lukewarm water and I have to hit the reset button on the thermostat. I originally thought it was just one of the 2 heating elements had gone bad. So I went ahead and changed both heating elements figuring this would solve my problem. Of course 2-3 days later I have lukewarm water and I have to hit the rest button. My question is could it be the thermostat is bad? If so how can I tell other then just replacing it? I have the temerature set to 130 degrees which is recommended for both elements. Is there anything else that could cause this?