Black tank flush question

[Luc]

Went our first trip with our new 3611.When connecting the black tank flush there seems to be very little flow. When disconnecting the line water comes back out due to built up pressure. Can't imagine that nozzles would be pluged from factory. Otherwise love the 3611.

[jcurtis934]

You can really only see flow out of flush system if you have a clear section in the sewer line. If you are judging flow by what your ear is telling you, then you may not be totally accurate. Also, it could be that the built in back flow preventer (under the bath sink or behind shower wall) could be stuck closed or partially closed resulting in no flow or reduced flow. Check that out. John

[rohrmann]

You will have water exit the flush fitting each time, but that is only water in the line between the backflow valve and the outside fitting. If the backflow device was stuck, you may not get any water to drain out when done. We drain our black tank about weekly, and flush each time and get the same drainage each time.

[WaltBennett]

You could remove the backflow valve from under your sink and put a new one in the convenience center instead of the plain hose fitting. That way there won't be any water to squirt back.

[BB_TX]

Ours is a 2007. But when the flush is turned on you can definitely hear a substantial spray going on inside the tank, even after 8 years of use. And the additional "stuff" that comes out the drain shows it is doing its job.

I did eliminate my anti siphon valve a few years ago after it started leaking. But the sound is the same now as when the valve was still installed.

[Art-n-Marge]

I have the same experience to offer as BB_TX except with my '06 unit which might for us is over 10 years of use. Love how it works. However, I did not mess with the anti-siphon valve in any way.

The only problem I've seen is that sometimes the backflush does so well, I see nothing coming our via the clear adapter, until there's enough water pressure, then Whoosh, comes what was causing the blockage. Much patience is required to clear it out sometimes. I also will close the black tank flush valve and backfill the tank 4 to 10 mimutes to backfill the tank and get more stuff out of there.

I guess this won't help with your problem, but it's what you want to hope for how it's supposed to work. As mentioned prior, I've had my rig over 10 years and as long as we are generous with the water when flushing, this should prevent anything permanently sticking to the tank. Like you imply it sounds like there's a problem with the backflush plumbing not allowing enough water to spray correctly.