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Discussion Forum

4 to 3inch waste drain

rez | Posted in General Discussion on August 7, 2009 05:23am

Got to looking at the finished product of a toilet to waste stack the other day.

I get to doctor the first and second floor walls back to acceptability after the replacement of a beat cast iron vent stack to PVC.

 In the basement I see the plumber weaved 4inch PVC around some copper feed lines via the use of 3 elbows

then used a 4 to 3inch adapter joining that elbow configuration to a sloped horizontal 5ft length of 3inch pvc joining into the 3inch vent stack.

Seems odd to me to use the 4inch elbows when they could have just went to 3inch right at the stool flange

and thus eliminated the sloped/horizontal catch where the 4inch meets the 3inch

but I’m not a plumber so thought to ask if this is an acceptable functional setup?

Thanks

 

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Replies

  1. User avater
    plumber_bob | Aug 07, 2009 05:59pm | #1

    If the 4" fittings are actually in the vent system and doesn't handle any waste, then It shouldn't be a problem.

    Why the plumber did that? I can only figure that he didn't have the right parts, so instead of running off and getting them, he used what he had.

    If waste and solids pass through these fittings it is probably best to replace them with the right fittings. Going from a larger pipe to a smaller one is just plain wrong, (well in most cases).

    I hope this helps alittle.

    1. rez | Aug 07, 2009 06:29pm | #2

      Thanks.

      Yes, the 4inch fittings were the 3elbows directly beneath the stool and bent around joining the 5ft length of 3inch running to the stack

      thus making the lipcatch at the reducer fitting.

      Guy's been a longtime plumber and taught at schools so figgered no problem let him run whatever just so's I could be free of the responsibility.

      Then seeing this it reminds me of how often I see weird stuff done by recommended licensed plumbers

      like at my aunt's old place where she wanted a castiron toilet line replaced that ran across the basement to the ext. wall then the septic.

      Friggin' recommended licensed plumber not only didn't pitch the lines out but actually left the lines with a pitch leaning back towards the stool! 

      Sometimes just don't know what to say. 

      1. User avater
        plumber_bob | Aug 07, 2009 06:48pm | #3

        I wish I could offer more help, but I need some good visuals before I start runnin' my gums much.It's hard sometimes to give good helpful advice, without seeing the prob first hand.Can ya throw up a pic or 2?If you see puddles under the pipes,....don't play in them! :-)

        1. rez | Aug 07, 2009 07:13pm | #4

          Later I'll stop over and snap a couple pics just for the interest.

          Looks ok except for the 4inch going to 3 thus forming the catch lip. 

          1. User avater
            plumber_bob | Aug 07, 2009 07:23pm | #5

            Cool I'll be waiting.

          2. User avater
            popawheelie | Aug 07, 2009 07:35pm | #6

            I'm picturing you waiting for pics of waste plumbing. You must really like plumbing! ;^)"There are three kinds of men: The one that learns by reading, the few who learn by observation and the rest of them have to pee on the electric fence for themselves."Will Rogers

          3. User avater
            plumber_bob | Aug 07, 2009 07:47pm | #7

            Well I've been waiting for pic's from the train ride but, so few are coming thru, that,.....well...... at this point I'll take anything I guess!!!It's sad I know.... :-(

      2. rez | Aug 08, 2009 03:53am | #9

        I sucked at taking these pics but it'll have to do. Just wasn't thinking and trusted the flash then shot hurriedly so the camera probably moved some.

        "In the basement I see the plumber weaved 4inch PVC around some copper feed lines via the use of 3 elbows

        then used a 4 to 3inch adapter joining that elbow configuration to a sloped horizontal 5ft length of 3inch pvc joining into the 3inch vent stack."

        "The 4inch fittings were the 3elbows directly beneath the stool and bent around joining the 5ft length of 3inch running to the stack

        thus making the lipcatch at the reducer fitting."

        View Image

         

        View Image

         

        Edited 8/7/2009 8:58 pm ET by rez

        1. bobtim | Aug 08, 2009 06:42am | #10

          you typically can't reduce the size of a drain line with the one exception being the toilet, 4" to 3". but I seem to remember it had to be right at (under) the toilet.

           Your set-up looks like a clog waiting to happen. Might be hard (fer sure harder than need be) to snake.

          My guess is the plumber had an "off" day.

          1. DonK | Aug 08, 2009 07:22am | #11

            Rez;

            Not sure what jurisdiction you are in, but here in VA, that's a clear code violation - for the exact reason you suspected.

            Don K.

            EJG Homes   Renovations - New Construction - Rentals

          2. rez | Aug 08, 2009 05:47pm | #12

            ya, got the red light flashing about the guy when I first saw it.

            Thing is, he was being eyeballed to replace the plumbing in a house that had been closed up undrained and unheated for a goodly number of years.

            And I don't want to do it. I play plumber only when situations dictate and not by choice. :o)

            Now I get to tell the owner what happened and let him decide what he wants to do. Hate when that happens.

            Thanks 

          3. DonK | Aug 08, 2009 06:20pm | #14

            I do plumbing more often than I want to sometimes. My father was a licensed plumber (among other talents) so I had some early exposure to it. He didn't teach me enough, so I still have lots to learn.

            One thing that I have found which makes life easier is the PEX tool. I didn't want to spend the $$ on it originally, but boy does it speed things up for water lines. If you don't have one, you should try it out. It makes installation so quick that it almost becomes fun.

            Don K.

            EJG Homes   Renovations - New Construction - Rentals 

        2. rez | Aug 08, 2009 05:53pm | #13

          In the grand scheme of things beyond the realm of right and wrong, how important is this disfunctional junction?

          Is the worse that can occur the headache of a periodic snake job? 

          1. User avater
            plumber_bob | Aug 08, 2009 06:55pm | #16

            Okay, first off:

            Like you suspect, and others have stated, this is wrong!

            Now with that said, if this has not be clogging or leaking so far, then
            you can probably get by with leaving it as is, for now!

            If it was me, I'd be collecting the needed parts to fix it right.

            The simplest fix that is legal, (in some places), is to use a 4x3"
            "Ecliptic" adapter. (I think that's the word)

            View Image

            This adapter can be used to replace the current adapter. Just make
            sure the 3" is on the bottom. In waste lines the rule of thumb is
            to "Maintain a smooth internal waterway"

            These adapters come in plastic, or the rubber clamp type.

            You will probably have to get this from a plumber supply, and it may have to be ordered. It is the simplest legal fix, here in Kentucky.

            How long will it last without changing anything?

            I can't predict that one. Could be years without a problem, or, it
            could start to cause problems on the very next flush.

            Snaking a toilet with a closet auger would probably open up any clog
            that may occur.

            If you need more input or info, lemme know.

            And keep it flowing down hill! 1/8 to 1/4 inch per foot would be cool.

            I hope I have helped.

          2. rez | Aug 08, 2009 07:08pm | #17

            Well,

             I sure hope the sh!d don't hit the fan when I discuss all with the owner.

            Thanks all. 

          3. Shacko | Aug 08, 2009 10:11pm | #18

            My take on your picture: Cut out the four inch fittings, get a four inch x three inch closet bend (they are legal), repipe in three inch. Check the pitch on the line, dosen't look like its enough (1/4inch per ft. for three inch pipe), put some hangers on both sections, your call.

            BTW You probably need a vent near the toilet.

             "If all else fails, read the directions"

          4. rez | Aug 09, 2009 03:20am | #21

            Been thinking about it this afternoon. Seeing that's the only sore spot what I'm going to do is discuss it with the owner and recommend he contact the plumber

            and have him ask what he would charge to redo the 4 inch elbows in 3inch and join it to the 5ft line since the original bid was so reasonable in the first place.

            If he does charge it'll be little and a small price to pay to keep things smooth for future work.

            Hellof away to do things I know but it will get it done and keep the peace

            as well as helping gauge the attitude of the plumber.

             

            Edited 8/8/2009 8:31 pm ET by rez

          5. Shacko | Aug 09, 2009 05:18pm | #22

            Lots of luck.

             "If all else fails, read the directions"

          6. rez | Aug 11, 2009 05:12am | #23

            Client called today from out of state and asked what I thought about the plumbing. Told him about the lip going from 4 to 3 and he says he is going to contact the plumber.

            So I drop by his building as I saw him out there and asked him if he'd got the call.

            He'd used a transition reducer for a smooth flow and guarenteed satisfaction.

            Kinda felt stupid as I should have approached the plumber first before speaking with the client but the client had called out of the clear blue so I had to to speak.

            Hate when that happens.   

          7. Shacko | Aug 11, 2009 08:12pm | #24

            I don't want to stir the pot, but did he change anything?, if not he still has a concentric reducer on that 4x3in. line; one of the worse places to put one is at the discharge of a toilet, almost guaranteed to cause future stoppage problems.

            Did you address my other questions?, no hangers on the pipe and a question about proper pitch?

            I don't want to get picky, but its starting to look like why his price is so reasonable, sorry.

             "If all else fails, read the directions"

          8. rez | Aug 11, 2009 08:28pm | #25

            Right, wrong, good, bad and ugly.

            The owner is satisfied and the plumber is a regular in the community who says he will stand by his work.

            I'm going to be dealing with him in the future and have already said my piece. Any more and I think it would be detrimental.

             'Course because of you now I'm going to have to check things again just to satisfy my curiosity. snorK*

            Can't see the need for a hanger as I could hang off that pipe and my pre 200 days have been behind me for a while. (No pun intended).   

          9. Shacko | Aug 11, 2009 09:34pm | #26

            Its fine if you are happy with potential code violations as long as you recognize them when you see them, have a good one.

             "If all else fails, read the directions"

          10. Shacko | Aug 08, 2009 10:17pm | #19

            plumber_bob: They are called excentric reducers; I think you would have a hard time finding one in PVC-DWV.

             "If all else fails, read the directions"

          11. User avater
            plumber_bob | Aug 08, 2009 10:28pm | #20

            Thanks, I've only used them one time actually, but it did save alot of work.
            They are seldom used, but we did get one from Master Supply in Louisville, when we needed ours.

  2. rdesigns | Aug 08, 2009 01:10am | #8

    The only acceptable place to reduce from 4 to 3 in the direction of flow is in the vertical line that drops directly beneath the toilet. This should be done by means of a a smooth-sided fitting, not a bushing, but what is often called a bell reducer. (In this case, it would be an increaser.)

    Without knowing more, I'd say the guy messed up, just as it appears to you.

  3. User avater
    popawheelie | Aug 08, 2009 06:29pm | #15

    I would let it go. But that's just me. And it's your call.

    "There are three kinds of men: The one that learns by reading, the few who learn by observation and the rest of them have to pee on the electric fence for themselves."
    Will Rogers

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