Brand New Urinal, No Siphon, How to Troubleshoot?

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DBCooper

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UPDATE: This issue is fixed, please read below for the background. Post #25 shows a properly functioning system: Brand New Urinal, No Siphon, How to Troubleshoot?

I built a brand new bathroom near my outdoor pool. It's all brand new plumbing, and as part of the project I wanted to add a urinal. I purchased a Kohler Dexter that has a "siphon jet". I purchased a Sloan 186 with 1gpf diaphragm.

This was installed by the plumber who did all the plumbing for the bathroom. I purchased the urinal and valve, and he admitted to not having a lot of experience with urinals, but he's a master plumber and compared to the rest of the job, this seemed trivial. However, the urinal doesn't work great. It does flush, but it flushes only because it fills with so much water that gravity sort of just whirlwinds it down. Here's a video of it:

The main issue is that the volume of water becomes so high it splashes out of the bowl (not a ton, but enough to be bothersome, especially when it's pee). Trying to slow down the water flow, I did try a 0.5 gpf diaphragm and that made the situation worse (not enough water to get the entire body to flush). I've also adjusted the control valve to every imagineable position and now have it right at the minimum needed to get it to mostly clear the body of water (as shown in video). Any more and it's just more water, any less, it doesn't fully flush.

In troubleshooting, I tried putting my finger over/around the siphon jet port and during flush I feel NO pressure/flow out of that hole. Not even a little. I called Kohler and spoke with a lady in CS there, I don't think she knew what she was talking about as she kept saying air should come out of that and kept pointing the blame to clogged drain venting, but this is a brand new build and my other toilet works and I did run the hose through the vent pipe, I just don't buy that. I'd also think the siphon jet would work and that'd I'd just have slow draining in this case.

I don't know what to try now except possibly replace the urinal. Is there any way I can troubleshoot this? I did stick a small plastic wire through it to see if anything was blocked, I got it in a few inches and nothing obvious happened. I couldn't get the piece to bend beyond a few inches. I don't know how the siphon system works in terms of the porcelain plumbing and design, but I assume it feeds just through its own channels just like the top four flush jets do? I blocked two of those jets to try and increase the pressure and still nothing coming out of the siphon. The Kohler lady kept reminding me nothing can go wrong with a purely porcelain urinal and that it's just a piece of china. She kept pointing to venting or slope angle being my issue, but I still think water should be felt out of that siphon. My buddy has an older dexter and you can really feel the jet pumping out.

Any help? Anything I should try. I can get a new urinal and then return this one to Lowes if needed, but before I just want to know if there's anything else I can try to narrow it down.

Finally, thank you so much for taking the time.
 
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Jeff Handy

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It looks like a partially clogged drain or poor venting.
But I also have limited experience with urinals or Sloan type units.
 

DBCooper

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It looks like a partially clogged drain or poor venting.
But I also have limited experience with urinals or Sloan type units.
Thanks for the response.

The venting is pretty simple, the drain it could be, I'll post a picture I have of it pre-construction, but it's not a great angle. I think the issue I have is even if it was a bad drain/venting issue, I still think I should feel pressure from the syphon jet. Assuming that, a drain/vent problem would still be an issue as the water coming down and from the jet can exit fast enough, but the pure lack of anything coming out of the siphon jet concerns me. I feel as if that siphon is the magical part of this design to get the water moving rather than just waiting on gravity, but I'm no expert.

Here's a picture. This was before the vent pipe was completely ran up and exits out the roof near that light.

Red is the drain area, so the urinal exits through that 90 degree through the stud and then directly down and out. I have no issues with the toilet or shower which are on the same line. Above that you can see the copper supply line that feeds into the Sloan valve. The blue line is the vent which in this picture ends around halfway up the window, but it was finished out and piped through the roof, it's a fairly big PVC pipe (1.5 or 2" sticking out of the roof). I also circled a green thing. This is covered by a chrome vanity piece and I can access it. However, it's now a piece of metal with maybe a square/robertson type tool required to move. Presumably I could remove that and test venting again, I may have the plumber do that when he's back.

Again, I just would think that siphon should pump out some water to help it exit the urinal instead of relying exclusively on a top fill and water volume play.

2020-04-21_19-45-28.jpg
 
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havasu

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If you pour a cup of water into the basin, do you hear it bubbling up, or does it drain just fine?
 

DBCooper

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If you pour a cup of water into the basin, do you hear it bubbling up, or does it drain just fine?
Thanks for the troublershooting step. I'd say it flushes well and fast. It does that same little gurgle at the end and a few bubbles I think are the result of water splashing, but it flushes real fast. Here's a video:

 

DBCooper

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Just for grins, I flushed the Kohler 1.6gpf toilet directly next to it, I could feel lots of water coming out of it's siphon jet and it flushes GOOD. Again nothing on this Dexter urinal though, not even the lightest of pressure. Not sure if the siphon is inter-related with venting/drainage, logically to me (the village plumbing idiot) it doesn't make sense that would be shut off if there was a drain issue.
 

Geofd

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if it drains well with just a cup of water try filling a 5 gallon bucket dump it continuosly see what happens
what is the urinal gal per flush rated for should say on the top of the urinal the parts inside the the flushometer have to match the flush rate of the urinal.
go to the sloan web site it will give you a break down of parts inside the flushometer if you read the directions there
is a black ring under 2 rubber parts if you take the flushometer a part the ring say side 1/side2 in the directions it will tell you which is for syphon
 

DBCooper

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if it drains well with just a cup of water try filling a 5 gallon bucket dump it continuosly see what happens
what is the urinal gal per flush rated for should say on the top of the urinal the parts inside the the flushometer have to match the flush rate of the urinal.
go to the sloan web site it will give you a break down of parts inside the flushometer if you read the directions there
is a black ring under 2 rubber parts if you take the flushometer a part the ring say side 1/side2 in the directions it will tell you which is for syphon
Geofd, thanks, I tried to address that in my initial post. The video I posted earlier showed quite a lot of water, probably half a gallon going in, I can try the Homer bucket.

In regards to the gpf, the urinal is a 0.5 - 1 gpf unit. It literally says 0.5 gpf on the porcelain, but the web site and directions say "0.5 or 1.0 gpf based on flush valve". I have both diaphragms and have tried both. The 0.5 just won't even flush at all, not enough water to make it fully wash away the waste. The 1.0 is what's in the video. I'm unaware of there being a specific side, but I will go check, that may be it. Perhaps the siphon is shut off which would solve the problem, I've just put those pieces in without regard. Let me check and report back.
 

DBCooper

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if it drains well with just a cup of water try filling a 5 gallon bucket dump it continuosly see what happens
what is the urinal gal per flush rated for should say on the top of the urinal the parts inside the the flushometer have to match the flush rate of the urinal.
go to the sloan web site it will give you a break down of parts inside the flushometer if you read the directions there
is a black ring under 2 rubber parts if you take the flushometer a part the ring say side 1/side2 in the directions it will tell you which is for syphon
Maybe I’m not following the side 1/2 part. Here’s the valve instructions:

I thought you were taking about the diaphragm but now I don’t think we are taking about the same thing. Maybe it’s a lower piece?

I see there are references to refill valves in other flushometers that have side 1/side 2 but that doesn’t exist in my model.
 
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DBCooper

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Here's images of the diaphragm, there's no refill valve which is the piece that seems to have the side 1 and side 2 guidance. This is the specific valve I bought:

20200722_213459343_iOS.jpg20200722_213516691_iOS.jpg
 

DBCooper

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During my last bit of tinkering, I actually felt vacuum on the siphon jet, not a huge amount, but as it was flushing I could feel it pulling a tiny bit. It just seems that water isn't routing down that and perhaps the high speed of the water coming through the top is pulling some air and creating a vacuum, it's baffling.
 

Matt30

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I didn’t get a chance to watch the video, but a siphon jet urinal will not give you a forceful flush. It’s pretty much a trickle. I think you are thinking of a blowout type urinal.
 

DBCooper

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I didn’t get a chance to watch the video, but a siphon jet urinal will not give you a forceful flush. It’s pretty much a trickle. I think you are thinking of a blowout type urinal.
Thanks, my friend has the same urinal/valve combo, perhaps an older model, but effectively the same equipment. Additionally, I'm not feeling a trickle, if anything I'm feeling vacuum.

While I haven't compared myself, I did ask him to check and he said he could definitely feel the pressure. He sent me a video, you can see at the end that it appears the siphon is doing more filling than the actual top jets:
 

Geofd

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Here's images of the diaphragm, there's no refill valve which is the piece that seems to have the side 1 and side 2 guidance. This is the specific valve I bought:

View attachment 24890View attachment 24891
Geofd, thanks, I tried to address that in my initial post. The video I posted earlier showed quite a lot of water, probably half a gallon going in, I can try the Homer bucket.

In regards to the gpf, the urinal is a 0.5 - 1 gpf unit. It literally says 0.5 gpf on the porcelain, but the web site and directions say "0.5 or 1.0 gpf based on flush valve". I have both diaphragms and have tried both. The 0.5 just won't even flush at all, not enough water to make it fully wash away the waste. The 1.0 is what's in the video. I'm unaware of there being a specific side, but I will go check, that may be it. Perhaps the siphon is shut off which would solve the problem, I've just put those pieces in without regard. Let me check and report back.
on the second pic the black piece that the diaphragm and disc thread into that ring may flip over
what i would suggest is call sloan tell them what urinal you have and they will match up the correct kit
 

Geofd

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Geofd, thanks, I tried to address that in my initial post. The video I posted earlier showed quite a lot of water, probably half a gallon going in, I can try the Homer bucket.

In regards to the gpf, the urinal is a 0.5 - 1 gpf unit. It literally says 0.5 gpf on the porcelain, but the web site and directions say "0.5 or 1.0 gpf based on flush valve". I have both diaphragms and have tried both. The 0.5 just won't even flush at all, not enough water to make it fully wash away the waste. The 1.0 is what's in the video. I'm unaware of there being a specific side, but I will go check, that may be it. Perhaps the siphon is shut off which would solve the problem, I've just put those pieces in without regard. Let me check and report back.
I'm sure you have done this but make sure the stop is all the way open
 

anticlmatic

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Try a new urinal if it isn't too much of a PITA. Watching your video gives me the impression that the jet is blocked somewhere, somehow. I had installed a new (regular) toilet once and had a similarly lousy flush as the one you have. Ended up being a piece of white plastic that somehow got into the jet portion of the toilet. It was acting like a check valve- only getting pushed up against the back of the hole and blocking water when water was trying to escape. I only realized it was there by using a mirror. Since it was larger than the hole itself, it took a lot of effort to get it out. No idea where it came from. Something similar might be happening with your unit. Just an idea. See if you can come up with a way to block the other streams and force water out of that thing. Valve seems to be working well and the draining/venting seems to be working well. I don't know what else it could be. For some reason you're just not getting water through that thing correctly.
 
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Fmkehoe

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Years ago I worked for a plumbing supply in Brooklyn New York and every now and then we came across a vitreous china urinal that had the jet blocked with China. In other words the hole wasn’t cleared. I don’t know if that’s the case with yours or not but it is something to consider.
 

DBCooper

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Thanks for all the help. I'll call Sloan today and see what they say regarding siphon and configs. Might just order a second one as well just to have bases covered.
 
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