I have a 8 yr old Reliance 501 hot water heater that seems to be working just fine until I got my monthly electric bill. I turned the heater off at the breaker and the electric meter stopped spinning, so I am sure it is the water heater. How do I track down what part in the heater is defective? The lady at the electric co. said she had a customer that had a bad thermostat in his heater and replaced it and he was fine. My heater looks to have four thermostats. Is there a way to test them? Any idea what else it could be. I am on a rather tight budget right now and I would rather not call a plumber. I installed the heater myself, so I can do some things. Any suggestions would be appreciated.