Brand New Urinal, No Siphon, How to Troubleshoot?

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DBCooper

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Is the pool an infinity edge?
It doesn't have a lower catch basin, but it's effectively a reverse knife edge. Water line sits a few inches below the edge but the combination of glass and angle give the effect. Considering there's nothing behind the pool except the woods, deer and coyotes, the added cost/complexity and maintenance of an infinity catch didn't make sense, there were also safety considerations as a true infinity would allow a floating device to very easily float over and we have young children in the pool.

I may try with the wife's help to plug all four of the top drains and see if I can get anything to come out of the siphon, but I'll call Sloan here shortly.
 

DBCooper

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Sloan customer service is top notch. 30 second wait time, really helpful person. He told me to try a few things I already tried including removing the colored part of the diaphragm just to see more flow. I tried that yesterday and it didn't get the siphon working. He suggested I make sure the vacuum breaker tube/pipe isnt jammed way into the urinal spud too far potentially missing the inlet of the siphon, but he said this part should work perfectly with the urinal and thinks it's a porcelain issue.
 

DBCooper

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Did you tell sloan it was a residential install. What psi is the incoming home pressure
Yes, my pressure at the line closest to it is 65psi, Sloan said only 25 is needed. Based on the sheer ferocity of the water coming out of those jets, he nor I felt we had a pressure problem. Granted, I lack the equipment to test pressure directly at the source, I'm pretty experienced in water pressure in general and have a decent feel for it.
 
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DBCooper

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Hi team, I'm here with a happy report. I got a replacement Kohler Dexter urinal, and despite what the Kohler support lady told me, this thing siphons good. You can feel real pressure and the situation is completely rectified. There is definitely something defective in the internal plumbing/casting on the old urinal. It works great on both 1.0 gpf and 0.5 gpf diaphragms. I'm going to leave the 0.5 in there as I like the short flush, but if I need more volume, I can swap out for the 1.0 in about 60 seconds.

Thanks to all for the troubleshooting help and education! It was all easy to do, and now I have a thorough understanding of how urinal valves work and drainage, I also saved my plumber a trip!

Here's a video documenting the change:
 
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breplum

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Grand results. Thanks for updating. Now, we all know that the siphon hole is integral to a good flush.
Glad I never had to deal with that particular defect.
 

DBCooper

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Yeah, I hope this is a learning lesson for all. If it wasn't for the bad advice from Kohler, this would've been a more trivial fix. My gut instinct was right, it functionally didn't make sense nothing would come out of that hole. As stated, this is a critical function for flushing. In fact, with that now properly operating siphon, significantly less water comes out of the top down jets and overwhelming majority of the flush and fill action is coming from the siphon. I sent a note to Kohler with my original case and the before/after videos and an explanation that they shouldn't push back and advise customers you can't feel siphon action. Home Depot was stellar in taking the return, I do wish I tried this earlier.

Since it was installed on July 1st, this has been a major disappointment, and my wife thought we'd be stuck with this splash-back pee-spreading fixture forever. I can't state how elated I am now to use this, and it was fun to learn how all this works!

The one blessing in disguise here is that had I not gone through this, I wouldn't have ordered the 0.5 gpf diaphragm. While the 1.0 works fine now and siphons great, it's overkill amounts of water and extends the flush time and loudness of the flush. The 0.5 provides such a refreshingly short and quiet flush, so despite the bumps in the road, now I have what I think is a more ideally sized flush setup, and I save my bill and the planet half a gallon every time this thing is used :)

Thanks so much for the support.
 

Jeff Handy

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I doubted the bad China issue, so good job following your instincts.

Now you will have to install a bidet, just to keep things lively, haha.
 

DBCooper

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I doubted the bad China issue, so good job following your instincts.

Now you will have to install a bidet, just to keep things lively, haha.
I think it's hard to imagine a defect, particularly on a new unit, and without being able to see it, it's hard to diagnose. I really just felt I should feel something regardless of downstream drain issues, but like I said, I'm the village plumbing idiot.
 
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