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Connecting Trap Primer to ABS Trap?

willflysatellitesforfood | Posted in Construction Techniques on December 14, 2006 08:54am

Was wondering if anyone could suggest the proper means for connecting the outlet of a 1/2″ trap primer valve to the inlet of a 2″ ABS p-trap?

Building Inspector wasn’t keen on my original plan to route the 2″ floor drain in the base of my Floodsaver washing machine surround to an open-ended pipe that would exit over the corner of a garage utility sink.  Instead wanted me to trap it and connect to the waste system…

Picked up a 1/2″ primer valve (Precision Plumbing P2-500), and have figured out how to connect it to the cold water supply.  However, am unsure as to the best way to connect its’ outlet down to the trap.  The outlet of the (brass) valve is 1/2″ pipe thread, and the trap will be 2″ solvent weld ABS…

Of course, the friendly full-service BB’s don’t have any pre-formed fittings suitable for obvious application…

Any thoughts from those who may have encountered this situation?  I’d like to be able to connect this up tonight so I can call for a follow-up inspection tomorrow…

Thanks in advance for the help!

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Replies

  1. tmiltier | Dec 14, 2006 09:16pm | #1

     

    After hearing that the primer valves fail or need cleaning frequently I choose to use a trap gaurd.

    http://www.trapguard.com I used the one to retrofit into a 2" pipe.

     

    Todd

    1. User avater
      willflysatellitesforfood | Dec 14, 2006 09:20pm | #2

      Todd:

      I appreciate the suggestion - I've seen those in other posted threads...

      Inspector insists on a primer...

      End of story, as far as options go...  (unfortunately)

      Jim

  2. McPlumb | Dec 15, 2006 12:30am | #3

    Since the primer is on a potable water line he's going to jump up and down and have a hissy fit if you don't leave an air gap.

    1. User avater
      BillHartmann | Dec 15, 2006 02:08am | #4

      I would have though that. But the drawing show it directly connected to the side and it has a backflow preventer..
      .
      Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

    2. User avater
      BillHartmann | Dec 15, 2006 02:10am | #5

      http://www.pppinc.net/index.php?action=view_document&path=%A6%DD%D4%DA%9E%DB%E6%CB%C2%D4%9E%E6%EE%DF%90%C9%DF%D0%DA%D0%C6%9A%A1%9E%DB%C9%D5%C9%9E%E3%DC%DB%D5%C7%D3%DE%DA%DB%90%B8%E1%DE%DB%DD%C4%DC%E2%9E%CB%DA%C2%D8%8F%BF%E9%D1%CE%CD%E1%E2%A6%B8%92%88%D0%DD%DB%88%B1%9A%9E%BF%A8%C7%B1%9A%CE%C3%E9%C9%D1%C7%BF%E1%E0%D5%C6%DA%E2%9D%DF%DC%CE%D4&did=1158699346
      .
      .
      Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

  3. User avater
    willflysatellitesforfood | Dec 20, 2006 06:14am | #6

    Let's see...

    I connected up the trap primer to the drain.  Checked all over Nibco's website for ABS fittings that might provide an attachment means for the primer outlet.  Ended up with the following solution - 1/2" copper from the outlet of the primer down to the 2" p-trap.  Used a trap with a 3/4" "cleanout plug", removing the plug...

    Inspector found it "interesting" today, as he'd never seen it connected that way before.  He wanted to do a little research to verify that it "wasn't illegal"!  Does anyone know whether this solution is illegal, per the UPC (in effect here in Los Angeles)?

    I welcome any and all comments/information...

    1. McPlumb | Dec 20, 2006 05:41pm | #8

      If the PI accepts Okay Dokay.

      Guess my worries would be sediment collecting in copper below trap.

      A unoin to clean it might be handy.

      Drain water can be extremely corrosive on copper.

      But like I said if he accepts it smile and thank him.

    2. plumbbill | Dec 26, 2006 06:07pm | #11

      JJ is correct about the "bap" adapter.

      That is what we use when we cannot connect to the side of the floor drain on an ABS system.

      I'm not sure if I could find a specific answer in the UPC governing your paticular design. I know my inspectors would not pass it.

      Couple of reasons, you can't make a connection to the bottom half of the pipe on a drain line. & that would interfere with the flow of the waste through the fitting.“How many observe Christ’s birthday! How few, his precepts! O! ‘tis easier to keep Holidays than Commandments.” —Benjamin Franklin

      1. User avater
        willflysatellitesforfood | Dec 26, 2006 06:26pm | #12

        All - I appreciate the feedback...

        My inspector didn't care for it either - I'll have to re-do it...

        I found the appropriate fitting after surfing the web a bit for it:

        http://www.pppinc.net/index.php?action=view_document&path=%A6%DD%D4%DA%9E%DB%E6%CB%C2%D4%9E%E6%EE%DF%90%C9%DF%D0%DA%D0%C6%9A%A1%9E%DB%C9%D5%C9%9E%E3%DC%DB%D5%C7%D3%DE%DA%DB%90%B8%E1%DE%DB%DD%C4%DC%E2%9E%CE%C9%D5%CD%E1%8F%BB%D1%D4%DC%E1%D8%D9%DD%D5%D1%DE%DD%A6%B8%D3%CD%D2%D8%EA%D1%D0%D6%8F%BF%E9%D1%CE%D1%DD%D6%97%A9%C5%C9%DF%E3%DC%DA%90%B8%E1%D4%DA%D1%D4%D1%DE%DD%D6%B8%D3%D1%DC%D8%E5%CF%C0%A9%D3%D3%D8%D8%D5%D7%E1%CE%C7%B8%A2%96%D7%E3%E4%D4&did=1158705574

        Just wish these fittings weren't so obscure and that I'd found it sooner!

        Hope everyone's holidays are happy...

        Jim

        1. plumbbill | Dec 26, 2006 06:53pm | #13

          Yup that is the fitting.

          Hey ya found it faster than I did.

          But I just call up my supply house & order them.“How many observe Christ’s birthday! How few, his precepts! O! ‘tis easier to keep Holidays than Commandments.” —Benjamin Franklin

          1. User avater
            BillHartmann | Dec 27, 2006 11:34pm | #14

            You know how stuppid this whole thing is.It is only catch any water that MIGHT leak out of a washer.Just dumping the drain through the wall would have worked, being function, and not any hazard to life or limb or health. And it would have been reasonably priced.Just dumping the drain into a utility sink would have worked, ... ditto, ditto, ditton.Tying it into the house drain using a Trap Guard would have worked ... ditto, ditto, ditto..
            .
            Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

          2. plumbbill | Dec 28, 2006 04:40am | #15

            Oh yeah the hoops ya gotta jump through just to protect against a possible flood that are very rare.“How many observe Christ’s birthday! How few, his precepts! O! ‘tis easier to keep Holidays than Commandments.” —Benjamin Franklin

          3. riverdale | Dec 31, 2006 02:15am | #16

            In my situation my new second floor laundry will be on the opposite side of the wet wall for the bathroom. Since I am building pedestals to raise the new washer and dryer up off the floor I thought I could run the drain from my floodsaver surround and T it into the overflow pipe of the tub. The overflow is right behind my washer and it is connected to the tub drain which is trapped and wouldn't need a primer. What do you think to this solution which is by far the simplest if it is allowed?Thanks.

  4. Howard_Burt | Dec 20, 2006 07:52am | #7

    There is a special no hub cast iron trap that has a 1/2" threaded inlet welded onto the inlet of the trap.  Tyler and Zurn are the brands that immediately come to mind, but I would think everyone makes them as they are very common in commercial work. I have never seen one made from ABS or PVC but that doesn't mean they don't exist. Checked a plumbing supply house yet?

  5. Shacko | Dec 20, 2006 08:43pm | #9

    I don't know of any codes that will allow the hook-up that you show. The connection should be before the trap. That means on the inlet side of the trap before the seal. If you have a proper trap primer back flow should be built into it. Best that I can do, lots of luck.

    ...........................................
    "If all else fails, read the directions"
  6. jjones | Dec 26, 2006 12:53am | #10

    i think the fitting you need is called a bap addapter  basicly it is a abs coupling with a 1/2 in. mip by 3/8 compresion fitting inserted through the side

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