Plumbing Question...........

[robertwhite]

Can I do this on my kitchen sink......................

Kind of creating a P-Trap hybrid

Concern is that the waste water won't drain properly.

 

[volleyball]

No you cannot if your dimensions are to scale.

 

[MEngineer]

Do you not have room or something? I would definitely try to install the DW fitting on the left most portion of your drawing.

 

[Kamn]

That trap is huge, you will have a lot of **** trapped in there

 

[robertwhite]

Do you not have room or something? I would definitely try to install the DW fitting on the left most portion of your drawing.

??? The DW fitting is on the left side just as shown.

That trap is huge, you will have a lot of **** trapped in there

No you cannot if your dimensions are to scale.

All I am using is a normal SCH 40 PTrap 1 1/2"

The 1 1/4" down pipe w/DW inlet comes from the sink drain, down about 8 inches (below the DW fitting) and then is converted with a 1 1/2" fitting into the standard P-Trap.

All I have done is to add the extra maybe 4 inches of pipe which then goes into the extra 90* fitting and then into the floor drain pipe which goes out of the house.

Are you saying if I add that 90* elbow, it will clog the system?

My concern was that the water would not be able to force thru thr P-trap and then over the extra 90*


If this won't work, what needs to change? I can NOT change the floor drain point.

***Just tried to make the pic clearer***

 

[lee91103]

you'll need a vent for it to drain properly...usually runs up from the vertical pipe...if you are not able to tie in to an existing vent you could put in a studor vent or air admittance valve and run it as high up in a cabinet as you can

 

[robertwhite]

you'll need a vent for it to drain properly...usually runs up from the vertical pipe...if you are not able to tie in to an existing vent you could put in a studor vent or air admittance valve and run it as high up in a cabinet as you can

Forgot to mention that...There is a 1 1/2" vent from where the sink connects to the main drain just below the floor. There is a Y with one side being the vent up the wall and thru the roof.

 

[theoldwizard1]

The outlet from my garbage disposer goes through a standard chrome-over-brass, 1½" P-trap and then run almost 12" horizontally before going into the 90° elbow that is inside the wall. No clogs in that horizontal section.

 

[tmcelheny]

Im fairly certain it will work fine

 

[Kaizen]

I'd put a sweeping 90 under the dishwasher inlet over then go down with a normal trap. so make pretend you have a double sink and this is the left one. just omit the right one. I'd want the water to be doing straight down after the trap so it doesn'tt siphon

 

[robertwhite]

The outlet from my garbage disposer goes through a standard chrome-over-brass, 1½" P-trap and then run almost 12" horizontally before going into the 90° elbow that is inside the wall. No clogs in that horizontal section.

You know what? A light bulb lit up in my head when I read the bolded part.

What I am planning is absolutely no different than if I ran a P-trap, then a horizontal, then into a 90* at the wall, which then goes straight down just like you have (and most thru the wall set ups). Just in my version, the "wall" is non existent.

Thanks man.

 

[volleyball]

Yeah still isn't going to work.

 

[The Cobbler]

you are making an S Trap. it could cause a siphon and **** the trap . s traps are not permitted here.

 

[dfiler2]

Use a Standard P-Trap then be sure to keep the trap arm level so your trap won't siphon. Here is a link that shows what you are doing, scroll down a little on the page and you will the issue you are dealing with covered. It mentions here the trap arm can not be over 3' by code.

http://www.smartplumber.com/article-225/drain-repairing

 

[robertwhite]

Yeah still isn't going to work.

Why?

you are making an S Trap. it could cause a siphon and **** the trap . s traps are not permitted here.

How am I making an S trap? There is no difference between the trap I am doing with a floor drain and a regular P trap thru the wall.

Use a Standard P-Trap then be sure to keep the trap arm level so your trap won't siphon. Here is a link that shows what you are doing, scroll down a little on the page and you will the issue you are dealing with covered. It mentions here the trap arm can not be over 3' by code.

http://www.smartplumber.com/article-225/drain-repairing

My trap arm is only 6 inches or so before it goes into the 90*.

Can someone explain how my trap is any different than a regular P trap that goes thru a wall? When regular P trap goes thru a wall into a 90* it then goes straight down till it hits main drain, right? How is this any different?

My trap arm will be level up to the 90* so why won't this work?

Don't take my drawing as to scale, exact, or anything else, it is just to show what the plan is in a rough drawing.

The Sani T is below the floor just as it was before (except it was an ancient metal pipe that I replaced with pvc all the way from the wall to the main drain Y)

 

[blazentrout]

It will work fine.Not quite an S trap but close. Not the best way with the 8" drop out of the bottom of the sink(a 3 or 4" would be better) but some times you do what you got to do. If i remember to, i'll take a pic of my mud/laundry room sink. Its pretty close to what you drew only it has an air admittance valve added to the line above the 90 to help with venting (keeps the sink from making a gurgle sound every once in a while when the washer drains). my vent for this line is screwy so that why we added it.

 

[HoosierMark]

I had a similar issue and just installed a normal trap and used a couple of 45 degree elbows to get it to the floor area the drain was in. I would be concerned that the length of the trap would slowly cause a build up for debris and end up clogged.

 

[Leaflessshadetree]

Why?




How am I making an S trap? There is no difference between the trap I am doing with a floor drain and a regular P trap thru the wall.




My trap arm is only 6 inches or so before it goes into the 90*.

Can someone explain how my trap is any different than a regular P trap that goes thru a wall? When regular P trap goes thru a wall into a 90* it then goes straight down till it hits main drain, right? How is this any different?

My trap arm will be level up to the 90* so why won't this work?

Don't take my drawing as to scale, exact, or anything else, it is just to show what the plan is in a rough drawing.

The Sani T is below the floor just as it was before (except it was an ancient metal pipe that I replaced with pvc all the way from the wall to the main drain Y)

The difference is that you won't have the vent. You have a 90 instead of the Tee and vent shown in the picture.
The water flowing down that section is what could cause suction that would pull water from your trap.

I think it will work fine, but depends on how far away the vent is.

 

[volleyball]

I don't get why you don't want to use a proper trap?
Your second pic is better than the first but still not there.
If you want to know , YOU need to do a proper drawing.

 

[purosananto]

I don't think the concern with your setup is that it will clog, but instead whether a siphon effect will cause your trap to be empty and hence not serve its purpose.

If this ultimately is going into a floor drain, isn't there a trap already there?

 

[volleyball]

Clogging is a big concern and how does he expect to clear it with glued pipe? As among other problems.

 

[purosananto]

Clogging is a big concern and how does he expect to clear it with glued pipe? As among other problems.

I believe OP said he is using a standard p trap, not creating his own with pipe fittings.

 

[Gerald O]

How am I making an S trap? There is no difference between the trap I am doing with a floor drain and a regular P trap thru the wall.

Yes there is a difference.

Can someone explain how my trap is any different than a regular P trap that goes thru a wall? When regular P trap goes thru a wall into a 90* it then goes straight down till it hits main drain, right? How is this any different?

That is not correct. When a P-trap arm goes into the wall it normally goes directly into a sani-T fitting, not a downward 90. The difference is that you don't have a vent in your drawing. It will not meet code.
There are variations allowed; for example it can turn 90 horizontally when it goes into the wall before getting to the T. This counts as an extension of the trap arm and the total still must not exceed the maximum horizontal arm length before the vent T.

The Sani T is below the floor just as it was before (except it was an ancient metal pipe that I replaced with pvc all the way from the wall to the main drain Y)

Then the way it was done before was not properly vented. They used to do stuff like that before they figured out how to properly vent drains to keep sewer gas out of your house.

If it's not vented directly at the point where it turns down at the end of the P-trap arm, then it's an S trap as drawn. Put in an air admittance valve if you can't otherwise vent it conventionally, then you'll be good to go.

 

[robertwhite]

The difference is that you won't have the vent. You have a 90 instead of the Tee and vent shown in the picture.
The water flowing down that section is what could cause suction that would pull water from your trap.

I think it will work fine, but depends on how far away the vent is.

The vent is right next to the trap.

I don't get why you don't want to use a proper trap?
Your second pic is better than the first but still not there.
If you want to know , YOU need to do a proper drawing.

Pretty hard to show a "proper" drawing while doing it with a mouse an MS paint.

If this ultimately is going into a floor drain, isn't there a trap already there?

No. This pipe is right at the side of the foundation and ties right into the main drain. It is the closest hook up to the field. I could put a trap under the house, but what would change?

*** This is what it looks like under the house***
The drawing shows a side view of the Sani Y pipe which hooks into the top of the main and then flows out of the house.

The pic is obviously under the sink. Sink stub on left, vent from Sani Y on right, which goes into the wall and straight up about 10 feet to outside.

The only pipes under the sink that are currently glued are the wall stub for the vent and the stubs on the floor.

 

[robertwhite]

Put in an air admittance valve if you can't otherwise vent it conventionally, then you'll be good to go.

Ahhh, there was a air valve on the old two sink set up, where would I put it in the renderings shown?

 

[Gerald O]

Ahhh, there was a air valve on the old two sink set up, where would I put it in the renderings shown?

Replace the downward 90 with a sani T, add a few inches of pipe going up from the T (minimum of about 4"), and put the AAV on top of that.

 

[purosananto]

Replace the downward 90 with a sani T, add a few inches of pipe going up from the T (minimum of about 4"), and put the AAV on top of that.

I agree with this.

I also will now agree with what volleyball said earlier. If it was me I would not use a glued in p trap, but instead use one that you can remove if necessary to clean.

 

[Leaflessshadetree]

Instead of an AAV why not put a T instead of the 90 and run the top of it over and Tee to the existing vent?

 

[robertwhite]

Replace the downward 90 with a sani T, add a few inches of pipe going up from the T (minimum of about 4"), and put the AAV on top of that.

And just leave the current vent set up the way it is?

What if I eliminated the down pipe portion of the vent and ran a T of some kind from the sink P trap to where the vent comes out of the wall as seen in the pics? That way the P-trap and vent line are pretty much horizontal with each other?

BTW, I will be switching to a P-trap with a clean out plug. The top half (from sink to trap is screw on) and if I ever really had a problem, I could just crawl under the house to access the main drain and/or sink & vent pipes. I hate using the cheap plastic piping as it always eventually leaks.