Question about different PVC wyes (plumbing)

[aunsafe2015]

I'm adding a utility sink to my garage. I need a 3 x 3 x 1.5 wye to tie into an existing 3" drain line.

In terms of shape and size, both of these appear to be what I need:

https://www.lowes.com/pd/Charlotte-...n-dia-PVC-Schedule-40-Hub-Wye-Fitting/3132805

https://www.homedepot.com/p/Charlot...DWV-PVC-Wye-Reducing-PVC006011200HD/203396271

The wye in the Home Depot link seems to have some sort of perforated edge at the 1.5" opening, whereas the wye in the Lowes link does not appear to have the perforated edge.

Can anybody tell me what the difference between the two is, and why I would pick one over the other?

I also note that the two items appear to have a similar (if not the same) model number, so perhaps they are identical items and the Home Depot link is just a weird picture?

Thanks for any input.

 

[rlitman]

The picture isn't weird. The HD wye is built around a 3x3x2.5 mold that has a bushing cast integrally into it, while the mold for the Lowes version is the actual size.

I don't know why it would matter though.

 

[ripperd]

highly doubt it is perforated. Probably just strength ribbing.

 

[aunsafe2015]

I don't know why it would matter though.

In other words, you're not aware of any particular reason to select one over the other? They are basically interchangeable?

 

[rlitman]

In other words, you're not aware of any particular reason to select one over the other? They are basically interchangeable?

That's how I see it. Unless maybe the bulkier collar interferes with the fit somehow (though I can't imagine how).

edit: Now that I'm looking again, the Lowes fitting is Schedule 40, while the HD is DWV. I still think either should be fine for your purposes, but the Schedule 40 may be a little stronger.

 

[59 wagon man]

only difference is lowes fitting is smaller hub. hd version is basically a bushing in the hub to reduce it to 1.5"

 

[K'ledgeBldr]

First, you have the wrong fitting. What you need is a "sanitary tee".

If I understand correctly- you have a 3" DWV (vertical), and you want to tap that with a horizontal run that will go to a sink? If so, yes you need the sanitary tee- it's all about the venting. A wye used in that configuration restricts air movement for venting.

Also, depending on the size of the sink AND the run from the sink to the DWV- you may require more than 1-1/2" drain.

 

[aunsafe2015]

First, you have the wrong fitting. What you need is a "sanitary tee".

If I understand correctly- you have a 3" DWV (vertical), and you want to tap that with a horizontal run that will go to a sink? If so, yes you need the sanitary tee- it's all about the venting. A wye used in that configuration restricts air movement for venting.

Also, depending on the size of the sink AND the run from the sink to the DWV- you may require more than 1-1/2" drain.

The section of 3" drain pipe that I will be tying into is white schedule 40 PVC in my crawl space, and it is actually horizontal (with a slight slope, of course). In the attached picture, I would probably plan to tie into the longer solid unbroken piece of pipe at the right.

The pipe I will be tying in will be a 1.5" pvc drain pipe from my sink. It will be coming from the rim joist area shown in top left of the picture (where insulation is), and I could actually route it so that I tie into the existing 3" drain pipe from either a vertical position or a horizontal position. It looks like horizontal would be easiest in terms of avoiding obstructions. The sink will literally be on the other side of that wall, so the entire length of piping from the sink to the 3" drain pipe will be about 6 or 7 feet. My easiest option for venting is an AAV (code allows them in my area). Due to space constraints I was actually thinking about trying out a trap vent: https://ipscorp.com/plumbing/brands/studor/trap-vent/.

With that extra info, do you still think a sanitary tee is better? This one would meet my PVC size requirements:

https://www.homedepot.com/p/3-in-x-...-Sanitary-Reducing-Tee-C4811HD33112/100346965

I could reasonably easily do either a sanitary tee or a wye. I just thought a wye would be somewhat smoother flow of the grey water into the 3" pipe, and it will also be a little easier to tie my 1.5" drain pipe from the sink into the angled wye rather than the ~90* sanitary tee, but I think I could probably manage with the tee if that is the better choice.

 

[ripperd]

It seems a wye is actually correct if you are going to tye into the horizontal portion:

http://www.ncwhomeinspections.com/Sanitary+Tees,+Wyes+and+Sanitary+Combos

 

[LS6 Tommy]

The picture isn't weird. The HD wye is built around a 3x3x2.5 mold that has a bushing cast integrally into it, while the mold for the Lowes version is the actual size.

I don't know why it would matter though.

X2. Functionally, it doesn't matter, but as previously mentioned, you need a sanitary tee and the drain should be 2" minimum.

Tommy

 

[K'ledgeBldr]

The section of 3" drain pipe that I will be tying into is white schedule 40 PVC in my crawl space, and it is actually horizontal (with a slight slope, of course). In the attached picture, I would probably plan to tie into the longer solid unbroken piece of pipe at the right.

If that's the case, use the wye. But with that length I'd run 2" to the sink then reduce down for the trap and AAV.

From the link that was added in a previous post- you should see why you use one over the other in certain circumstances (the reference term "laying on its back" gives a good indicator to how it works or doesn't work).

 

[aunsafe2015]

If that's the case, use the wye. But with that length I'd run 2" to the sink then reduce down for the trap and AAV.



From the link that was added in a previous post- you should see why you use one over the other in certain circumstances (the reference term "laying on its back" gives a good indicator to how it works or doesn't work).

Yep, I saw that link and it was a good explanation. Thanks.

 

[scottydosnntkno]

In other words, you're not aware of any particular reason to select one over the other? They are basically interchangeable?

The Home Depot one is made using an insert in the mold, so they can mold 3x3x2.5 3x3x2 3x3x1.5 etc from the same master mold.

It’s not perforated, it’s just ribbed for strength. That much solid plastic would have huge sinks/warpage as it cools.

Either will work. And the ones at your store might not even be that particular manufacturers (pvc is a commodity usually made relatively locally to where it’s sold) so different states can have different suppliers

 

[stokefire7]

Home Depot has a bushing in the branch. I'd run 2", at the transition to your trap arm , a 2" 1/4 bend with a 2" x 1 1/2" bushing and no AAV.

 

[stokefire7]

Something like this...

 

[LS6 Tommy]

Something like this...

Just FYI, that S trap is a code violation.

Tommy

 

[stokefire7]

Just FYI, that S trap is a code violation.

Tommy

It's not.

 

[LS6 Tommy]

If that was done in ABS when the building was built, it's new enough that it was a violation.


Tommy

 

[stokefire7]

It's called a combination drain and vent.

 

[stokefire7]

I have a question for you. What's the shortest distance for a trap arm ?

 

[LS6 Tommy]

It's called a combination drain and vent.

I see no vent there, just reducing bushings.

Tommy

 

[LS6 Tommy]

I have a question for you. What's the shortest distance for a trap arm ?

2x the diameter of the trap. Less than that is a crown vent trap, which is also illegal.

Tommy

 

[stokefire7]

....maybe this will help

 

[stokefire7]

My trap arm is 6".

 

[LS6 Tommy]

....maybe this will help

Jeez. I'm a *****. I have no idea why, but I was thinking you meant the fittings in the pic were a type of vented trap setup. :tard:

Sorry. I'm getting old.

Tommy

 

[stokefire7]

aunsafe2015
This combination waste and vent system is code compliant for your area.

 

[aunsafe2015]

aunsafe2015
This combination waste and vent system is code compliant for your area.

Thanks. Got any more pics of a similar setup? My plumbing experience is limited and I'm not fully understanding what you are suggesting.

Edit: is the concept simply that if you use a waste pipe that has a large enough diameter, that you don't need a separate vent for the sink at all? And that the sink effectively uses the vent for the larger horizontal waste pipe that the 2" sink pipe connects to?

So I'd have my 1.5 in tailpiece and 1.5 trap, but I would go from the trap arm straight into a 2" waste pipe? And no aav necessary with that setup?

 

[stokefire7]

Thanks. Got any more pics of a similar setup? My plumbing experience is limited and I'm not fully understanding what you are suggesting. This gives you another option.

Edit: is the concept simply that if you use a waste pipe that has a large enough diameter, that you don't need a separate vent for the sink at all? And that the sink effectively uses the vent for the larger horizontal waste pipe that the 2" sink pipe connects to?
Yes, theory being , increasing one pipe size larger, will allow equalization of positive/negative pressure. The fixture IS vented. Third question is , yes.
So I'd have my 1.5 in tailpiece and 1.5 trap, but I would go from the trap arm straight into a 2" waste pipe? And no aav necessary with that setup?

Yes, I have another set up like this on my basement Lav.