lanerd wrote:
Actually, it can happen. If there were no one-way valve on the connection, the water flow back at the spigot to the fresh water tank could create a vacuum and siphon the water from he black tank (if it was full) back into the fresh water valve. That is exactly why the mfg'ers put the one-way valve on there.
Ron
that's why there is always water running thru my hose until I flip the inline valve which makes it improbable (impossible) for back flow. now if the campground water supply suddenly switches to suction, but that won't happen.
bumpy