I return seeking knowledge... and help The electric hot water heater is 4 years old (manufactured in may 2007). Been working no issues until 3 days ago. Now I only get about a 5-7 minute shower out of her. Water starts at the right temp but cools off fast. No leaks. Water pressure is fine. Water temp is fine to start off at least. So the question is.. why? She is heating, or I would have no hot water.. the temp is still set at 145ish (and the set valve is covered by a screw on plate so it is hard to change). It is like it is only heating 1/2 of the 50 gallon tank. Only good is that she is still under limited warranty, but looking for thoughts before I call my local HVAC guys (and to make myself smart!) Thanks in advance.