Water inlets

[smokjump]

I think I asked this question before but still confused. I have two water inlets, one of course is the fresh water inlet and there is one above that and it is not marked. I was told it was a black tank flush but when I hook up a hose basically nothing happens. I have traced the inside hose and it goes to my bathroom sink, no clue what it does there. Sooooooo my question is the same, what is the upper connection for??

[webslave]

Could still be a tank flush... Most factory installed tank rinsers go first to a "high point" (most often the bathroom sink) where there is a plastic "backflow preventer" installed. That keeps the possibility of a siphon effect pulling effluent from the tank up that line and out the side of your trailer... Sometimes those backflow devices fail and won't let the water flow through to the tank rinser. Look, again, under the sink and see if you see such a device in the line. If you do, and hooking water up to the line outside does squat, it has probably failed. You can get a replacement unit almost anyplace.

[smokjump]

Thanks, again webslave! I really appreciate your posts and your knowledge is a valuable tool for me as I try to navigate thru being a newbie at camping.

On second look I did see the line had a "tee" looking device at the top under the sink, kinda hard to see much less get to but I'll find and order the replacement part. Kinda like the loop in the dishwasher drain line I would guess. Our camper is 6 months old and this is already the third repair so I'm hoping that the bugs in the build process have been addressed.

Thanks again!!