I own a Bradford-White Corp Electric Hot Water Heater Model # I80R6DS13. It shuts itself off at least one a day. I have to press the red reset button to turn it back on. When it comes back on the water temperature is EXTREMELY HOT! The temp dial is even turned down. The heater was installed 6-1/2 years ago. (late 2002) Is this an easy fix? Is my heater still under manufacturer's warranty? Can anyone offer any advise to me?