Until a few days ago, my 40-gallon, electric water heater provided about 20 minutes of hot water for showers. Now, all of a sudden, it consistently provides only about 5 minutes of hot water. I checked the circuit breaker and neither of the 30amp fuses has tripped. I would like to diagnose the problem myself if it isn't too involved. So what would be the next step? (I have standard tools and a multimeter at my disposal)
I don't know much about water heaters, but I'm pretty sure most have two heating elements, so could it be that one of the two elements has gone bad in this case? I have also heard about thermostats going bad, so could that be it?
Anyway, would appreciate any advice. Thank you! Peter