Forum Discussion

RVcrazy's avatar
RVcrazy
Explorer
Sep 10, 2014

Y adapter for fresh water at park water supply post?

Hubby is wanting to put a Y adapter on the park water supply so that he can have both the gray hose & white hose hooked up at the same time. (This would be when we might need to drain & flush tanks du...
Seeking Advice
Old-Biscuit's avatar
Old-Biscuit
Explorer III
Sep 10, 2014
Typically located under bathroom sink/inside cabinet is a 'backflow preventor' that is part of the black tank flusher system.
Inlet line runs from side of rig then UP to backflow preventor then DOWN to black tank and sprayer.

Looks like this (or similar).......


IIRC they have been required since 2004

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