Wiring a new hot water heater
I need to replace an electric water heater and need some questions answered. It looks like my current heater is a single element one. I can't tell if it's 120 or 220 volt. The circuit breaker is 40amp but the wiring going to it looks like regular house wiring, ie: white and 14-2 maybe 12-2. The heater I'm going to use will be a dual element but both elements are never on at the same time. I thought when using 40amps and 220 volt you need 10ga or larger wiring. Can a water heater be 120volt and need 40amps?
please advise and thanks