Originally Posted by gljurczyk
That is true what you found but that doesn't meet the needs IMO being your tank is vented and not under pressure. Your trailer warning also states that the discharge valve must be open when in use. Can't cause a vacuum. Now don't fall out of your treestand tiring to text me back. The back flow preventer will stop any discharge into a city water line. Next question then how do the add-on flush systems that are sold and up to code do not supply one in the kit? I don't even think they come with a back flow preventer. I have checked mine and it looks like it go's directly to the tank.
In regards to them placing a Warning label to (Open discharge Before running BTF) this is a (CUA) for people who also say (No One Told Me to Do That)!
Even the (Cheap) BTF DIY Kits have a (Back flow preventer/Vacuum breaker) whatever you want to call (IT)! Just need something to keep (POO POO) out of our Fresh Water supply! Here is a little Aid, Thread Backflow Preventer Home Depot,Sku#789976,Price (4.27$) plus tax
! Buy it and (Screw It)on!
PS Sent from my (Deer Stand)!