Dishwasher Air Gap Needed with New Sink?

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harborremodel

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I'm replacing a sink and currently there are two 1.5" ABS drain lines under there (pic attached). The current dishwasher waste line goes to an airgap and then down drain line #1 (black trap in pic) while the sink goes down drain line #2 (white ABS trap in pic). The new sink has a single drain in the center rear of the basin that is much closer to drain line #1.

I'm wondering if i could just get a branched tailpiece for the new sink and have everything go down a single drain line. It'd just cap drain line #2 and it'd allow me to clean up the mess of plumbing under the sink and free up some room. Is there a reason why the original builder of the home would have not used this setup in the first place? I'm in Washington state so perhaps there is some local code that requires an air gap and separate drain?

2018-01-04 20.23.06.jpg
 
You can connect the drain as you plan, just connect the airgap to the sink tail piece.

Builders will often install a two part waste for a kitchen sink, because it separates a disposal from the sink waste.
 
Can't I eliminate the air gap that sits up on the sink? Doesn't the sink drain itself act as the air gap? Ideally i'd like to cap as many of the holes on the top of the sink as possible for a clean look.
 
The logic behind the high-loop, the airgap and those appliance that have intrinsic backflow prevention device is to eliminate the potential of waste water black flushing into a load of clean dishes.
 
Some dishwashers now have the hose clipped in a high loop right on the back of the machine so if you leave the hose clipped there you are good.
 
The photographer most likely has no plumbing experience. He's probably given the product to photograph and just sets it up uder studio lights for the best
image. My guess.
 
Ya think someone at home desperado has heard of photo editing????????
 
So, SnS works for home desperado?

I know reading is strenuous and mentally challenging, but this appears in virtually all home desperado links; "How can we improve our product information? Provide feedback."
 
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I suppose I am complaining to the wrong people. i could provide feedback but then I would want a consultant's fee.
With decades in the video business, i know a good shot from a bad one.
 
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harborremodel said:
Can't I eliminate the air gap that sits up on the sink? Doesn't the sink drain itself act as the air gap? Ideally i'd like to cap as many of the holes on the top of the sink as possible for a clean look.
Click to expand...

The air gap is required for the dishwasher to prevent backflow, it has nothing to do with the sink. You should be fine doing it your way, just keep the loop in the DW drain line.

Dave Mason
 
Ended up removing the air gap up top and just used a branched tail. The sink seems to drain a bit slower than it used to, I'm guessing the branch line creates a bottleneck where it comes in thus slowing flow. The dishwasher drains fine and this setup works fine.
 
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