2021 Interstate 19 Shower no drain!

[DaveG]

I have a shower that does not drain. No build up after a few moments of operation, it does not drain more than a few ounces. We never used the shower from new until a few days ago. The gray tank was less than 25% and we were on level ground. The sink has always worked well. I inquired at Airstream support. Absolutely useless response! I emailed and then called the dealer. Got a promise they would get back to me but no info yet. I investigated and discovered this is a very simple setup. The shower drains out the bottom edge side of the wall through a 90° elbow, connects to a back flow valve which connects to another 90° elbow which goes into the tank. I took the plumbing apart and discovered the back flow valve consists of a tube of silicone like material inside a pvc pipe. The tube is puckered on the drain end. Concept is water entering the valve will open the puckered end to allow flow but stop a back flow. The valve is about the exact same level as the shower pan so weight of the water pushing against the silicone tube is minimal. I can fill the valve up with water on the input side and it will not push the tube open. There is no way to raise the shower or lower the valve. I had almost enough water build up in the shower enclosure to start running out over the edge. What a great design - NOT! Has anyone else experienced this flaw in design? Did I get a crappy back flow valve? BTW this is a real bugger to work on! I haven't put it back together yet which will likely be even worse.

[uncle_bob]

Hi

The "waterless trap" (which is what you have) is a very common item in a lot of RV's. In most cases it works fine. The "flaps" don't take much pressure at all to open. Vertical / horizontal ... still works. Lots of AS RV's ( van or trailer ) has one in the shower. They all have the same "zero pressure" setup. They seem to work fine.

Best guess: Yours got some crud in it that has the flaps sealed shut. They seem to do better than they get frequent use. Leaving them with no flow is not a great way to do things.

Bob

[toskeysam]

I have had mine stick “mostly” closed. I took an old ear syringe, clipped off the pointed end. Filled the drain with a little water and placed the bulb over the drain. Popped it with my hand and the drain valve popped open. Drained great after that.

[DaveG]

Hey, THANKS!!! I believe leaving it dry is likely the cause as Bob suggests (thanks Bob!). I’m learning. And thanks toskeysam for the tip! Any ideas for what the pink hard foam is that AS used to glue the pipe in place at the point where it goes through the floor into the tank? Looks like insulating foam used in house construction.

[uncle_bob]

Originally Posted by DaveG

Hey, THANKS!!! I believe leaving it dry is likely the cause as Bob suggests (thanks Bob!). I’m learning. And thanks toskeysam for the tip! Any ideas for what the pink hard foam is that AS used to glue the pipe in place at the point where it goes through the floor into the tank? Looks like insulating foam used in house construction.

Hi

Best guess: that's exactly what it is.

Bob

[DaveG]

Not a "riveting" subject but I will report how this concludes rather than leave it shy of sharing what got it fixed. Status at the moment is all the components are clean inside and out, no obstruction, drain not working. Next is getting a replacement back flow preventer.

[guskmg]

Try using a small sink size "plumber's friend." They work good for winterizing the drains too!
guskmg

[uncle_bob]

Originally Posted by DaveG

Not a "riveting" subject but I will report how this concludes rather than leave it shy of sharing what got it fixed. Status at the moment is all the components are clean inside and out, no obstruction, drain not working. Next is getting a replacement back flow preventer.

Hi

Does the waterless trap pass water? Can you / have you forced water through it? If so, then that's not the issue.

Bob

[DaveG]

Originally Posted by uncle_bob

Hi

Does the waterless trap pass water? Can you / have you forced water through it? If so, then that's not the issue.

Bob

I removed the trap and cannot see anything wrong with it but this is the first time I have seen one and don't have one to compare with. I cannot see anything specifically wrong except it just won't open. Water exits through the wall close to the floor of the van which allows only a slight slope to the point it dumps into the gray tank under the floor. I can put an elbow on the inlet side of the valve and put water in it and at a point of almost full it will open slightly to allow some water out. Installed I can fill the shower pan to a point of near overflowing and the valve won't open. I can push water at the drain and it won't budge. There is nothing like "it will pop open" even when I had it out and put water in to observe. Is it suppose to "pop open" when weight of the water pushes against it? I have no experience with a normal function.

[DaveG]

If I got the image uploaded successfully this is what it looks like installed

[DaveG]

Originally Posted by DaveG

If I got the image uploaded successfully this is what it looks like installed

Well that didn't work and I even read the directions Oh well
(PNG 258 KB)
Value in the picture might be seeing how slight the slope, and short the distance to entering the valve which results in only a small amount of water and very little pressure on the internal tube which has to open to let water pass.

I will experiment with the photo thing again. I hit the upload and nothing confirmed anything happened. ........?

[Qurius]

Originally Posted by DaveG

Well that didn't work and I even read the directions Oh well
(PNG 258 KB)
Value in the picture might be seeing how slight the slope, and short the distance to entering the valve which results in only a small amount of water and very little pressure on the internal tube which has to open to let water pass.

I will experiment with the photo thing again. I hit the upload and nothing confirmed anything happened. ........?

Many have had the same problem with the "trapless" drains in the nineteens including me. They are made by LaSalle Bristol and called Utopia Uniguard. The issue seems to be that the inner bladder which has a support under it called the "Inner Guard" must be in the 6 o'clock position (which they don't say in the instructions). It is a challenge to get it to stay in that position when tightened down because it is not locked to the outer flange. If you look at the spec sheet at the bottom of this page you can see how it's suppose to look when installed. https://www.lasallebristol.com/plumbing/uniguard/

I hope that helps get your water draining again...

[DaveG]

Originally Posted by Qurius

Many have had the same problem with the "trapless" drains in the nineteens including me. They are made by LaSalle Bristol and called Utopia Uniguard. The issue seems to be that the inner bladder which has a support under it called the "Inner Guard" must be in the 6 o'clock position (which they don't say in the instructions). It is a challenge to get it to stay in that position when tightened down because it is not locked to the outer flange. If you look at the spec sheet at the bottom of this page you can see how it's suppose to look when installed. https://www.lasallebristol.com/plumbing/uniguard/

I hope that helps get your water draining again...

MANY THANKS! Much help!
So that tung depressor is suppose to be at the bottom?
I didn't see a picture in the instruction sheet. That is where I placed it when I started but it could have easily rotated when tightening. I will check it again.
Thank you again!!!

[TitusNW]

Dave,


I don't know the exact model of trapless valve you have but I was wondering if the orientation of the valve 'flaps' make a difference.



I see the Hepvo valve has requirements for horizontal installation,

"When installed at any angle other than vertically, the HepvO must have ‘ribs down’ to ensure correct drainage." https://hepvo.com/installation-maintenance/


Perhaps your valve was not installed with the correct orientation - if it was necessary.


Steve

[DaveG]

Originally Posted by TitusNW

Dave,


I don't know the exact model of trapless valve you have but I was wondering if the orientation of the valve 'flaps' make a difference.



I see the Hepvo valve has requirements for horizontal installation,

"When installed at any angle other than vertically, the HepvO must have ‘ribs down’ to ensure correct drainage." https://hepvo.com/installation-maintenance/


Perhaps your valve was not installed with the correct orientation - if it was necessary.


Steve

No ribs. Likely more info soon. Thanks!

[DaveG]

Higher than just a guess that the valve is defective. Won't know for sure until a new one is in and all functions. Talked with the manufacturer and learned that there is no requirement for one side or the other to be up or down when used in a horizontal installation. Info sheet attached:
UniGuard Brochure - new2.pdf

[DaveG]

I'm stumped and baffled. After some back and forth with Airstream I received a correct replacement valve. I installed it today and if there is improvement it is barely noticeable. I can easily accumulate several inches of water in the show pan before I hear a trickle. After considerable time it will drain down to about a half inch plus and then stop. Sink drain is okay. Kitchen drain is okay. No idea what to try or test.

[TitusNW]

Dumb question, but have you snaked the full shower drain line? A mig gun liner (Harbor Freight, etc) can be used as plumbing snake for small pipe.



Steve

[DaveG]

Hi Steve, The drain is really simple. Water exits the enclosure through the wall at floor level into a PVC 90° elbow which connects to a Utopia back flow preventer. From there it makes another 90° right into the gray tank. It is a bugger to work on! The back flow device is just a silicone sleeve in a tube which is molded in a way to stay closed at the discharge end. Concept is weight from water entering the tube will open it but water from the outlet side will not. No actual P traps are in the plumbing. I can't get it to a dealer until next year so if I get restless enough I may take it apart once again and go all the way to the gray tank? They must assemble all of this ahead of installing and then glue it into place using expanding foam. After that they put the cabinetry around it. Did I mention it is a bugger to work on.

[BRVanlife]

We purchaaed a new Interstate Airstream 19 in 2021. We have also had problems with the shower drain that does not drain. Even using a squeegee to direct the water to the drain, I would hear barely a trickle go down. I was afraid to try anything on my own to correct it since it was under warranty .Called the dealership and was told this is a known problem, no current solution! We barely used the shower because of this problem, which is very frustrating considering the price and we like to boondock!! Spoke with a rep this past Sept at an RV show and was told there is a fix for the problem. He said it's about the "venting". I take the van to the dealer tomorrow, hopefully will be using my shower without problems in the spring!