Plumbing, Bottle Traps, P traps

[Ben Abate]

Hello all,.
My question is about the newer style Bottle Traps for vessel sinks. I'm nearing the end of a remodeling project and I'm using a vessel sink with a pop up drain and a Bottle Trap. The granite top is floating and I wanted to use a Bottle Trap for appearances. My question pertains to the long plastic sleeve inside the Bottle Trap. How does that work? I see that the tail pipe of the drain slides into the bottle like most traps do but you usually have a compression ring to seal that connection. The long sleeve blocks the water from draining to the wall drain if left long like it is. I feel pretty dumb right now for not figuring this out I even looked on You Tube before posting this question but found nothing to explain the plastic tube. If left in place I can't see how water drains and if taken out I can't see how these Bottle Traps keep the odor from coming back up the drain. What am i missing.

Thank you
Ben

Possibly I just found the solution to my dilemma, I see the Bottle Trap has a larger diameter than the plastic sleeve which tail pipe of the drain seals against. So if I'm correct in my thinking water goes to the bottom of the Bottle Trap and goes up along the sides to wall drain and in turn keeps the odor from coming back up. Is this correct? I never took the bottom cap of the Bottle Trap off to examine it until after I posted. I didn't delete because maybe this will help someone one day as they read of my dilemma.

Thank you all again and if you have something to add to this please do, especially if I'm incorrect with my assumption or how this Bottle Trap works.
Ben

[Stan Calow]

Ben, the diagram on this page helped me figure it out: https://dengarden.com/home-improvement/Why-Do-We-Need-Bottle-Traps-For-The-Wash-Basins

Seems to me like they'll get full of gunk after awhile.

[Paul F Franklin]

The plastic sleeve is what makes the trap work. It doesn't (shouldn't) extend all the way to the bottom of the case, but is designed so there is a gap between the bottom and the end of the tube with water always covering the bottom of the plastic sleeve. This is what blocks the sewer gas. As water drains through the tube, it will rise up around the outside until it flows out the drain connection.

This might be useful: https://secure.img1-fg.wfcdn.com/docresources/17219/122/1224756.pdf

[Ben Abate]

Hello fellows,,

Thank you for the reply to my post. You guys came up with photos and descriptions pretty quickly compare to myself this morning. I've had this trap sitting around for awhile and gave it some thought but never really tried to figure out how it really worked until today. Nice looking but i was confused because I'm used to the old "P" traps. Heck at one point I thought I needed to cut that plastic sleeve to let water drain, glad I started to look online and asking questions. But after I posted and then edited my post because I thought I figured it out but really needed you fellows to reassure me.. I would have hated to have water all over the place in our new bathroom. I'll post a few pictures of the Bottle Trap I'm using.

I really do thank you fellows for the replies
Ben

[Grant Wilkinson]

Looking at the pics, I can't figure out how these differ in function from P traps.

Can someone enlighten me, please?

My issue is the kitchen sink. The drain backed up recently and when I started taking things apart, I saw that the builder had more elbow3, traps and Tee than were allowed by the code that I read. This resulted in the waste water moving so slowly in the pipe that finally led to the stack that, over years, the sludge built up in that pipe. I removed every thing and re-plumbed from the sink to the pipe leading to the stack, which I cleaned out.

All is well except now the drain is noisy, as the water from the sink first drops straight through the kitchen floor to an elbow and from there to a P-trap. There is something like an echo from the water hitting that first elbow. This did not happen in the original set up, as the plumber had put two elbows close to the sink. These served to slow the water down, for sure, but also caused the sludge problem.

Now, back to my question. The bottle trap seems to hold water like a P trap, so may well not be my solution, but maybe if you guys can enlighten me on how they differ from P traps, I can better see if a bottle trap would help me quiet things down.

Thanks much.

[Paul F Franklin]

They function exactly the same in that there is a pool of water that prevents sewer gases from escaping from the drain system into room air.

The main difference is that bottle traps can be made more attractive and so are often used when the plumbing will be visible, such as with open vanities or pedestal sinks. Like p-traps, bottle traps need to be periodically cleaned to eliminate the "gunk" that tends to accumulate.

Your problem is that the maximum length of a sink tailpiece, by code, is 24". Since your tailpiece goes straight from the sink to under the floor, it likely exceeds this distance. That means the water is traveling faster than it should be when it hits the trap. This can lead to two issues. Excessive noise is one, as you have noted. The other is that if the water is moving too fast, it can flush too much of the standing water out of the trap, and allow sewer gases to bypass the trap and enter the room. While 24" is the max, it's best to have it much shorter.

You also have to pay careful attention to the slope of the drain pipes as too little slope will lead to faster buildup of "stuff" and too much slope results in excess water velocity. When properly sized pipes clog frequently, it is usually because of improper slope.

[Grant Wilkinson]

Tks, Paul. The length of my tail piece from where it joins to the sink to the elbow at the bottom is 21", so approaching the max. At the bottom is an elbow. The trap is a bit further along in the drain. I didn't change that part of the configuration when I did my "fix". Maybe I could quiet things down of I replaced the elbow with a trap?? That way the water would be hitting water in the trap and not the hard surface of an elbow. Any thoughts, please?