Be sure and fill up the water heater and test it's operation before your first trip. As others have now pointed out, if it is the electric hot water heater switch and you turned it on without water on the tank, you may need to buy a new heating element. Personally, if that's the case, you should press the dealer to replace it. After all, they failed to inform you of what that switch does.
Sent from my iPhone using Tapatalk