Black tank sprayer

check valve stuck?

I think you're dealing with a clogged check valve or the sprayer inside the tank is clogged.

I'll just tell you where the check valve is in our rig. We have a 2000 Winnebago Adventurer. The check valve is behind the mirror on the wall by the dinette. (When the dinette slide comes in... it covers that wall.) That would put it behind the knobs in the shower in our rig.

Seems we never thought about putting a SEDIMENT water filter on the hose when we are flushing and rinsing the black tank. We were camped in northern California and we KNEW there was a lot of sediment (sand) because we could see it build up in the mesh screen of the sediment filter on the fresh water hose.

That sand clogged our internal black tank sprayer.

p.s. Don't try using air pressure to unclog it. ... just saying don't.

Since there usually isn't much to these "sprayers", you may want to try getting a pipe cleaner and see if you can open up the flow. The fact that the hose has pressure, indicates that the problem is in the sprayer.

You may want to consider removing it, and putting it in a bowl of that CLR cleaner that is supposed to remove build-ups like this.

Good luck:)

my antibackflow valve always drains out after pressure is turned off.
bumpy

Jim......Your hose connection in the water bay runs to the other side of the coach to the top of the black tank. You have a door panel on the passenger side, opposite the water bay, with no latch. If you look under that panel, there will be two screws. Remove the screws and that entire panel will hinge upward.

Once open, you'll see all three of your tanks. On top of the black tank you'll see the sprayer with a plastic hose plumbed to it. The reason they clog is that when the tank has waste in it, it sloshes around while driving and enters the sprayer. Once you stop, it hardens and dries, plugging the sprayer. This will continue to happen, even if you clean the sprayer.

I fixed mine by removing the hose, leaving the tank sprayer in place and using a 1/8" drill and drilled down through the sprayer several times to open it up. The sprayer is only at the one end and really doesn't spray anything or clean the sensors from that position. With mine drilled out, I get more flow from the sprayer, flooding that end of the tank and rinsing the waste toward the drain.

The hose line has a backflow device in it, so if debris gets in the sprayer or hose, it can't wash back to your hose connection. That's why when you remove your water hose for the hose connection, you always get a back flood of water.

Probably a sprayer head clogged. Find the head and pull it from the tank. Usually 2-4 stainless screws under some sealant. When you have it out it's as simple as using a toothpick to open ALL the fine holes. Be sure you pull the hose off the top of the spray fitting. You'll be surprised at how much gunk can collect inside at the bottom of that fitting.

My HR was doing the same thing and it was the back flow preventer. It was located under my bathroom sink. If water runs out when you take the hose off, it's normal. If it sprays out, you have a clog. 50/50 either sprayer or back flow preventer.