we have two bosch dishwashers side-by-side in our new kitchen (still under contruction by me…) but today we have the granite coming in, and i was wondering if i should have the granite people put two holes in the counter for two air gaps, or can both DWs be plumbed to the same airgap? i’m guessing this more of a local code issue, but i can’t work with the city, they just run me in circles…
any help would be great,
thanks,
mike.
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Replies
Why do you need "air gaps"? Dishwashers are totally self contained.
F
isn't it so there are no backing up problems?
Oh, now it's clear - I think.The DRAIN HOSE needs an air gap. No problem. Just make sure that there is enough slack in the drain hoses so that you can secure it as high on the base cabinet as possible. This allows for an air gap to develope thereby preventing the dishwasher from siphoning waste from the sink drain. You don't need ANY holes in your countertop.F
i tell you, the "pros" out here are idiots... the company (mind you a fairly big operation here) that sold us the granite told us to drop the sink in so they could measure around it... i kept fighting it, but they insisted, so we did, and the installer shows up to measure and asks "why did you put the sink in first?" strike one. (same idiots told me the stove + downdraft should be in too... but i KNEW that was wrong). our plumber, who came highly recommended, used one 2" dia. hole to run all the power, hot water, and waste from our two DWs to the sink base... obviously thats why he wanted us to use two air gaps... i would think the extreme heat from both the hw supply and drain hose would be bad for the electrical, but what do i know?? i'm just a diy'er ;-)
thanks for all the help...
-mike.
Calm down Buckaroo!!!The sink, regardless of material should be undermount, NOT a drop-in, when you have a monolithic material such as granite. That's part of the benifit of stone. You can wipe the counter off and into the sink without having the sink lip as and obstacle to catch the scum.There should not be any problem removing the sink and adhereing it to the underside of the counter. You can then have holes bored - on-site - for the fixtures.As far as the 2" dia. hole - You don't know sh__ from shine-ola, so relax. There is nothing wrong with them all going through the same cabinet hole. The heat is not that extreme. And as I stated im my first post, the air gap pertains to the HOSE. You basically want the DW drain hose to extend above the BOTTOM of the sink floor (preferably up to the underside of the countertop) - any part of the hose, before or after it enters the sink base cabinet.Your CT Sub wants the sink and stove in place so that they can measure precisely for the countertops. If they cut wrong - short or out of alignment - the stone it worthless to them. $$$$.So, take a deep breath and come up with solutions rather than look for problems. The Subs are all trying to please you and you really don't know, as a DIY'er, how to define the beast, what the right questions to answer are, when to ask them or how to direct. Accept it and go into problem solving mode.This is exactly why people hire GC's. They deal with - anticipate - these issues. Why you felt that you would not have the same issues to address is beyond my scope of human understanding.F
the hole issue was either a local code, or a bosch requirement... i didn't pull it out of my @ss.
as for the sink, i had to lay down ply, cut the hole, install the sink, plumb it as if it was never going to move... and when they showed up, they took out the sink, tore out my ply, and threw down a crappy piece of 5/8. so where did that work get me? i was right, the sales people were wrong. the stove is a 48" cooktop, on an island, so there is no way i can install it before. they would not be able to get the granite in around it... it has a .5" overhang on the sides... the countertop piece is so big, and so narrow at the back, they have to cut it on the counter... i was right.
enough said... thanks again for the air gap advice.
-mike.
1. I can safely say that I have installed hundreds of DWs. NONE have ANYTHING which extends above the countertop, let alone require that ANY holes be bored through the countertop.2. You're a DIY'er, doing this for the first time, yet are calling others "idiots" and are researching how to do things AFTER they begin to go wrong. I suggest there are more "idiots" in the room than you previously counted.3. I imagine the CT Sub understood that he was dealing with a DIY'er and therefore asked that you jump through a few more hoops than a repeat/ GC customer would, to ensure that his time and materials were not wasted. Your time or materials were not and should not be a part of his equation.4. Admitting to being a DIY'er informs us of what level we are dealing with. Though it may excuse your lack of knowledge, it does not absolve you of responsibility. Step up to the plate. It's not about being right or wrong.5. We all- well, many - at BreakTime, enjoy helping DIY'ers and problem solving. That's why we subscribe. I never thought you pulled anything out of any part of your anatomy. If I may add: Everything seems to have remained exactly where it was prior to your first post.F
frank, relax... the reason i was asking here is because when the PRO told me that i needed two holes in my $7k counter tops for air gaps, it didn't seem right, so i wanted other opinions. i've never seen a home w/ two DWs have dual air gaps on the surface of one sink. besides, i've worked on many kitchens, either mine, or other family members, and several under the guidance of a GC, and thats why any protest i had came on semi-solid experience.
4. you assume my lack of pluming knowledge extends into other trades too... not a chance. and it is a matter of right or wrong. i was right, and had the idiots who were telling me otherwise have just paid better attention to the garbage they were dishing out, i could have saved myself hours of work... its about the opportunity cost, the loss of my time, which irritates me to the n-th degree.
-mike.
FWIW, I've probably inspected 2,000 home +/- with dishwashers.I've only seen 2 with a DW air gap, and neither was actually connected.Its one of thsoe model code things that might be adpopted in some places, and maybe even enfoced, but as someone said, check with your local authorities.
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sounds like there is some moble home methods in play up above..
(not yurs)
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Call your local plumbing inspector's office and ask them under what circumstances air gaps are required. Information from any other source is unreliable (even more unreliable than info from the inspector's office).
Probably a local issue. I've installed a LOT of dishwashers. Not a single one has an airgap. No problems with any of them. No matter what, you must make sure that the drain hose loops up to the top of the base cabinet and then back down to the dishwasher tailpiece on the disposal (or the tailpiece on the drain assembly if no disposal).
Good luck.
Seems like a Studor valve would eliminate the need for any air gaps.
First off, make sure you need air gaps. It's mostly a local code issue, but can depend on the model of DW. (And don't depend on the plumber to know this, one way or the other.)
If you need air gaps, you probably need two. Otherwise you'd run the risk of one DW pumping into the other. Even with the air gaps, you need to keep the two drain lines separated -- don't Y them together before they feed into the disposal, eg.