Waterless urinal venting

[Mark Olenick]

OK so I want to start a discussion here. I have decided to install a waterless urinal (brand withheld) based on the typical configuration. See Sloan or others for detail . Do they need to be vented? Now, I am not looking to decide one way or the other as I will be venting mine. However thinking about the operation my question is does it need to be vented and why? Or is this a new class of sanitary device that would not require venting that could modify existing code to make things simpler. Just curious on the thoughts out there as these things still are not main stream.

Just to clarify. These devices do not use any water except for "the stream" gong into them...

 

[Jadnashua]

I would think that a vent would be required just like in any fixture, since the p-trap could be siphoned otherwise.

FWIW, they tried these at a place where I used to work...they became a major maintenance issue and were removed. They ended up getting regularly clogged with crystallized urine, and were a smelly, messy cleanup job. The special 'oil' is not inexpensive, either.

You still have to clean them, and on many, that also calls for flushing them with a few gallons of water, so they DO use some, just not for each flush.

 

[Sponsor]

 

[Mark Olenick]

I would think that a vent would be required just like in any fixture, since the p-trap could be siphoned otherwise.

FWIW, they tried these at a place where I used to work...they became a major maintenance issue and were removed. They ended up getting regularly clogged with crystallized urine, and were a smelly, messy cleanup job. The special 'oil' is not inexpensive, either.

You still have to clean them, and on many, that also calls for flushing them with a few gallons of water, so they DO use some, just not for each flush.

From the picture I can't really tell if it is acting like a P or more like an S like in a toilet. They installed one where I used to work as well and wound up pulling it as well. That being said they are being installed all over on the PA Turnpike rest stops which I travel a bit and I have not noticed any oder.

How long ago was the one pulled from your place of work.?

Thanks
Mark

 

[hj]

Many areas require a "capped water line" in case the unit has to be replaced with a flush valve model, which WOULD require a vent.

 

[Jadnashua]

They tried them for about a year, then gave up.

For those that have not investigated this type of device...it has a trap in it to prevent sewer gasses, just like any plumbing device, but periodically, you have to add a special oil that floats to the top of the water in the trap. You have to pour a bit of water in there AND some more oil when servicing the thing. The urine is denser than water, so it falls to the bottom, and eventually goes out the trap after diluting the water there. If that gets too concentrated, the urine can crystallize, and clog things up. Then, the oil has nothing to float on, and things start to smell really nasty. IOW, cleaning the thing must be done religiously, and depending on the volume of users, more oil added. If not done, things will get funky. ANd, the materials costs are not inconsequential.

Water IS needed during the maintenance, along with the oil. You have to be careful about the cleaning materials, as you don't want it to contaminate the oil, so that it might get washed away and no longer be able to do its job. Dumping a lot of water fast could also wash away some of the oil. If the maintenance people are not schooled on the proper maintenance, things can go south quickly.