A word of caution: The Suburban manual discusses the operation of the water heater generically and not in conjunction with it being connected to a coach. Indeed, there is really no reason for Suburban to mention the electrical connections inside the coach, other than to specify electrical energy requirements, since there are thousands of applications of their product. That's up to the coach manufacturer.
Each coach manufacture should, in their instructions, adequately describe the function of both the electric and gas operation of the water heater, including the location of all switches, valves, etc. such that a lay person, the ordinary user, can fully and adequately understand how the systems work. Unfortunately, many don't.