From the manufacturer:
Vac/Check cannot be installed in an inaccessible location where venting of water from device during normal operation causes damage. It must be installed in an easily accessible location to
end user.
InstructionsMine was right next to my silverware and directly above the main electrical inlet, all hidden by the kitchen cabinet.
In order for a back flow problem to happen with the piece of junk removed, the tank would have to be full to the level of the sprayer, the check valve would have to fail, the water would need to be turned on, the campground water system would have to fail, the water pressure would need to drop below zero pressure and any back flow prevention provided in the campground system would need to fail. I weighed that against the fact that I did have contamination in the kitchen and a real electrical hazard. The code police don't sleep in my trailer. :Z