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Discussion Forum

Dishwasher’s Air =-Gap

hanalei | Posted in General Discussion on October 30, 2009 06:49am

This is in regards to a dishwasher installation (my son’s total home re-build) in Kauai, Hi.  All new kitchen, walls blown-out, under slab waste-lines altered, cabinets etc.. The stainless steel, extra-deep 2 compartment sink (KEY only on-island that was not a special order had 4 holes).  Prepping for granite a discussion arises what goes in that hole?  This is a spontaneous mutual echo from the concerned women (owner and mother).  That hole is for the air-gap.  The what?  No, no that’s where the soap dispenser goes.  The other 3 holes were long taken.

County code requires an air gap, therefore we (the plumber and myself) installed it under the main base cabinet very clean, very Pro.

Lately, I have heard of leaks under the kitchen sink.  There has been some discharge, we are in area where mold & mildew is on high alert.  I cautioned when deciding on the under cabinet installation that the dishwasher must always be checked when being loaded for any food, scrapes etc.. that may clog. And that all dishes should be rinsed before put in the dishwasher.  Before starting wash cycle check drain area to be free and clean.

After over 30 years as a GC, with a extensive and impressive resume’ did I make the wrong decision?

How best to correct.

Mahalo.

Bob

 

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Replies

  1. Karl | Oct 30, 2009 07:43am | #1

    Check with the dishwasher manufacturer. My Miele dw has a built in air gap. I think most bosch dw's have an integral air gap as well.

    I would run the drain hose in a high arc up to the underside of the countertop and down to the drain fitting and omit the air gap entirely.

    If you really want an air gap just drill/punch another hole in the sink or core drill a hole in the granite top for the air gap.

    I am surprised the sink wasn't undermounted and if it was I am surprised the granite doesn't overlay the sink holes.

    Karl

  2. McPlumb | Oct 30, 2009 09:33am | #2

    If your plumber is a licensed pro, trust his work, and send the women off to work on something they are good at.

  3. DanH | Oct 30, 2009 02:05pm | #3

    FWIW, most modern dishwashers don't need the air gap (so long as hose routing instructions are observed), but many codes still require it. (I'm surprised that code -- if it requires an air gap -- doesn't require it to be above the countertop.)

    Air gaps can leak if anything disturbs the flow from the nozzle to the orifice into which it sprays. This can be a bit of food caught at either end, or a slight misalignment of the two. Not sure I'd want one under the counter since this is all so iffy. (At the very least I'd want a bucket under the thing.)

    A strong nation, like a strong person, can afford to be gentle, firm, thoughtful, and restrained. It can afford to extend a helping hand to others. It's a weak nation, like a weak person, that must behave with bluster and boasting and rashness and other signs of insecurity. --Jimmy Carter



    Edited 10/30/2009 7:06 am by DanH

    1. frammer52 | Oct 30, 2009 10:34pm | #4

      Brand new LG installed last year, instructions wanted an air gap.

  4. brucet9 | Oct 30, 2009 11:43pm | #5

    I've been called out many times to fix an air gap that spews water all over the counter top when the DW drains. Most often the cause has been a clogged or kinked hose leading to the disposal. The thing may have worked fine at the time of installation, but over time has gotten clogged or kinked because of too sharp a bend.

    If the air gap is deck mounted, someone will see the problem right away and the cap may direct the water into the sink. Under the counter is out of sight, out of mind until they smell the mildew from under the cabinet.

    BruceT
  5. edwardh1 | Oct 31, 2009 01:09am | #6

    no air gaps in south carolina that I have ever heard of or seen.
    Possibly a solution looking for a problem



    Edited 10/30/2009 6:09 pm ET by edwardh1

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