[77newell]

On my 77 coach the switch is powered by 120V and then goes directly to the electric element in the water heater. Mine also has the indicator light to say it's on or off. If I had your problem and had made the checks you have I would switch the breaker off, pull the switch out its box, restore power and then test the switch on and off to see if power is passing through or not. I suspect it is not since you said the indicator light is off and I would normally expect it to light whenever there is power on the downstream side of the switch. If there is power downstream of the switch then I would check at the connections to the heater.

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