I have an electric water heater that is 5 years old. I normally turn it off when I am out of town. I turned it off last Friday and returned and turned it back on Wednesday. I am not getting hot water. I double-check the breaker box and have turned it on properly. Could it be that the wter heating element needs cleaning? Or could it be that I need a new themostat switch? Any tips on what steps I should take to fix this problem would be appreciated.