Black Tank Flusher Not Working?

[drjjj]

Our 3400RL is 11 months old. We have been stationary for most of that time, we are living it in full time while our next stick house is being built (then we hope to travel some). On the recommendation of our selling dealer, we leave both gray tanks open 24/7, and keep the black closed until the toilet "burps", then we dump it. The sensors always show that all three tanks are at least partially full. Our model (2007) has the built in black tank flusher. With our lifestyle we end up dumping the black tank about every 5-6 days. We have noticed that when we first had the trailer you could hear the flusher working while it was on, and see the water and "effluent" coming out after dumping. We always run the flusher at least 20-30 minutes after each dumping. I should also mention that we are using Thetfords "CampaChem" in the tank after each dumping. Later we noticed that while the flusher was running (we also have the clear elbow on the hose) that effluent would "pulse" out intermittently. Now when I turn the flusher on I hear nothing, and don't see any water coming out at all. My thoughts: 1) bring in a hose and fill the tank several times at the toilet and dump; 2) add some kind of organic material (enzymes?) to see if something needs to be "digested". Has anyone else had a similar experience with their flusher? I know some have advocated dumping a 20# bag of ice in the tank and taking the rig for a "ride". I would rather avoid that for at least 2 more months to avoid having to "break camp". Is it possible something has become disconnected? Thanks for any advice.

[ols1932]

If you have one of the flexible wands that you attach to the end of a hose and stick it down in the toilet clear down into the black water tank and run the water through it, you should see effluent coming out through your clear sewer elbow. If you do then you're flusher is not working. Be sure to have the black water gate valve open while you do it.

Orv

[Countryfolks]

That has happened to us several times. It's probably caused by the vacuum breaker in the line between the hose inlet and the tank. In our 5er that breaker is in the wall between the shower and the coat closet. In the older one it was under the bathroom sink. Note: there may be one under the kitchen sink/counter also, it causes a bad smell in the kitchen. Your dealer should be able to find it's location for you. They are fairly expensive [$30-$40]. I replace the first one with a spigot type valve that had to be manually opened and closed each time the tank was washed. The oem ones are always failing.

Skip

[sreigle]

The connection point for the black tank flush has, I think, a sediment screen. You might see if that screen is plugged. It should be visible when you remove the hose from that connection.

If that's ok, pull out the washer and the screen. Behind that should be a pin, probably white. This pin is part of a checkvalve to prevent blackflow. Push the pin to see if you get any pressure release.

It sounds to me like you are getting no water past that checkvalve. That's a bit of a guess. I've not checked ours to make sure there's a checkvalve there but I cannot imagine that there wouldn't be.

If none of that helps, pull the panel from around the connection center, the one that goes back into the basement storage area. Maybe you can see if the hose from the flush connector is kinked. Or if you are brave you could disconnect the hose from the backside, have someone turn on the water and see if you are getting water flow past the checkvalve. I'm afraid I'm not brave enough to do that although maybe holding a coffee can to catch the spray would make it workable.

If none of these things help, let us know and we'll try to come up with some more ideas. Or maybe someone already has ideas and will bring them forward now.

[foggyb]

I'm waiting for the final fix answer to this as mine has stopped working also. I suspect check valve but think I have to get to the tank to replace it. Dan

[sreigle]

One last thing about the checkvalve. If the rig was stored for the winter where it gets hard freeze weather, if that checkvalve had any water in it when stored, then the expansion during freezing may have pushed the o-ring out of place. I had that happen on an outside water fill once on another brand. That o-ring could block water flow, possibly.

[drjjj]

I just finished taking the mounting bracket for the black tank flush connection loose at the control panel. I did not see any type of filter screen or check valve-just plastic connections from a hose to the brass fitting that mounts on the panel to which you connect your water supply. I suspect that the problem is deeper inside the belly, beyond my expertise to diagnose. My unit is still under factory warranty. With a daughter getting married in five weeks in Colorado Springs I(we are in San Antonio) and our new house being finished in about eight weeks I may not have the time to get the coach in to the dealer for repair. I did purchase an extended warranty, so I hope it will be covered under that. I will keep the group apprised as to the outcome. Thanks again for everyone's advice and help.