Dishwasher drain trap question

Discussion in 'General Plumbing Help' started by DJB, Feb 13, 2018.

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  1. Feb 13, 2018 #1

    DJB

    DJB

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    Due to my kitchen design I cannot put my dishwasher next to my sink. Running the drain to the disposal would require me going through the 2 cabinet next to the sink and make a 90 degree turn. I have a wide open wall cavity behind the dishwasher and the basement below is wide open. I plan to run a 1 1/2 inch drain with p trap and air admittance vent to the sink drain in the basement. My worry is the pressure from the dishwasher drain washing out the p trap. Should I put a 90 before the trap to slow the flow down, and or use a deeper trap? Thanks in advance.
     
  2. Feb 13, 2018 #2

    Mr_David

    Mr_David

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    Not 100% on visualizing what you described
    You're going to run a 1-1/2" drain from dishwasher to a sink in the basement.
    That drain is just dumping into the sink?
    Why bother with a 1-1/2" drain and trap if it's not connected directly to sewer drain system?
    Just run 1" PVC line. NO 90's, easier to clean if you get a stoppage.



    Why not just run it to kitchen drain. just use 5/8 drain hose.
    Are you required to use an air gap?
    It not, run it high in cabinet right after you leave the dish washer so most of the waste water will drain out of hose into kitchen drain (disposal) after each use.
    use 3/8" type "L" copper for water. I see dishwashers installed that way quite often. Usually around the corner, then plus one cabinet.
    Rinse the dishes, turn and install them into DW. With 2 cabinets, depending on how wide they are, now you have to travel a bit to load the damn thing. Are you sure you want to put it WAY over there?
     
  3. Feb 13, 2018 #3

    TomFOhio

    TomFOhio

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    David, I think he is planning on hooking into the kitchen drain line in the basement and arming over to where the dishwasher is above and putting in a p-trap . Then putting the hose down through the floor and into the p-trap. No need for a 90. It will not empty out the trap. DJB, correct me if I'm wrong on your plans.
     
  4. Feb 13, 2018 #4

    DJB

    DJB

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    Thanks for the response guys. Tom you are correct, it will go into the pipe in the basement that the kitchen sink drains into. I was concerned with the trap washing out due to the dw pump forcing water into the pipe.
     
  5. Feb 13, 2018 #5

    TomFOhio

    TomFOhio

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    Thanks for letting us know. A washing machine drain installed properly has a trap and it pumps a lot faster than a dishwasher with no problems.
     
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