Vision 25 city water filling onboard tank.

[gcousins]

Recently our 1999 Vision 25 started filling onboard fresh water tank when connected to city water. I have no system plans or schematics. Does anyone know how the city and onboard systems are connected/isolated, or where I can find the offending check valve? Also, small black floating specks have showed up in the fresh water. Source?

[01blueox]

I would think the Rexhalls all pretty much have the same water systems. If you connect to a blue valve, you throw the handle one way to fill the onboard tank the other way for city hookup, maybe it's not all the way to the city side. As for the black specks disconnect from the city wrap a white towel around the spigit run water through the towel see if there are specks. If no specks then you need to sanitize your system. JMHO

[Full-Timers]

Water could be leaking back through the water pump.

[Bob_C]

The check valve in the pump probably has junk in it.......pull the pump and clean it....not a hard job...

[gcousins]

Thanks for all the suggestions.
I made a mistake in not following the suggestion of breaking the pump suction line and connecting to city water before I changed out the pump valve block so I don't know if that was the problem. After the changeout, it did not leak back.
The pump design is such that it is a check valve and I was convinced that the little black pieces were from one of the valves, but they all looked good. I changed the valve block anyway.
I ran the hose through a white cloth and found the source of the specks was the hose.
All is good.