Black Water tank wash out

Mabear

Member
We had an issue with water back flushing into our motor home when we cleaned the black water tank. It was fresh water that came out we believe from under the bathroom sink. Is there some kind of surge valve? We later found out that the water pressure at the dump was not restricted. Would appreciate any information anyone can give us.
 

danemayer

Well-known member
Hi Mabear,

Welcome to the Heartland Owners Forum.

Heartland makes 5th wheels and travel trailers, but no motorhomes. So the advice you might get on this forum is probably going to be generic; it may or may not apply to a motorhome.

In general, the black tank flush has an Anti-Siphon Valve so that if the city water pressure ever goes negative while using the black tank flush, the water supply is not contaminated. You could have one of those devices under/behind a cabinet or bathroom wall. If you don't use a water pressure regulator, and go to a park that supplies water at 100-200 psi, you could blow out the plastic Anti-Siphon Valve and spray city water all over the place.
 

JohnDar

Prolifically Gabby Member
If it is your Anti-Siphon Valve, replace it with a brass one (if you can get to it). The failure of the plastic ones is well known on these forums.


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