wildmanbaker wrote:
gutfelt wrote:
dougrainer wrote:
gutfelt wrote:
as I was also and now u see why u need a 90 degree 1/2X1/2 connecter to bypass this unneeded valve
Why is it unneeded??? Doug
ok I think u know what a I mean your not dumb so I ask why is it really required? I know exactly what its for and for the most part I thinks it code to have one but I don't believe its at all necessary
in a MH
Really? You a have been around long enough to know that if something can go wrong, it will. The last thing you want is to have the spray nozzle hang open after flushing the empty tank, and not knowing it, and finding out as your black tank fills. Remember the movie "RV"?
The anti-siphon valve will not prevent that.
What it does prevent is the drawing of water from the black tank into the potable water system should that be under negative pressure for some reason. One way that could happen is if the water pump were off and the city water connection off (so no pressure) and the tank flush valve left open and the outside shower were on and at a lower position than the black tank. It would siphon water etc. from the black tank into the potable water supply system. This may sound like a contrived situation, and perhaps it is, but it's certainly not beyond the realm of something that could happen to a slightly forgetful or distracted person.
It should be clear why the plumbing codes require devices or designs to prevent this sort of cross-contamination. (It's also why sinks and bathtubs generally need to have the spigots set above the flood level of the basin, and why toilet tank fill valves have anti-siphon valves built in, etc.)
