I know this spring I "forgot" which way I had turned the valves at the hot water heater to winterize it and got the same result you have.
The hot water heater access is usually toward the back or near where the kitchen sink is located........ Look under the sink, but there may be several other areas that these "valves" may be. I take it you did not have to "light" the hot water heater or you would already know where that part is....?
Most new ones have "Direct Spark Ignition", so you don't have to light a pilot light like you would in your home if it had that type of pilot light.
(called a standing pilot light).
I should tell you I don't have your brand of camper (mines a Cardinal) but this is generic with most campers. Someone will chime in soon with the correct answer or location.