# Dishwasher Drain **URL:** \ **Category:** Plumbing Inspections\ **Created:** [September 30, 2008, 9:33pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362 "2008-09-30T21:33:00Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![vsantos](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/vsantos/32/188006_2.png) [@vsantos](https://forum.nachi.org/u/vsantos)\ **Post date:** [September 30, 2008, 9:33pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/1 "2008-09-30T21:33:00Z")
I’ve never seen this configuration. Dishwasher drain connected just above the trap rather than the disposal. What are your thoughts on this setup? ![dishwasher drain.jpg](https://global.discourse-cdn.com/internachi/original/3X/0/7/07768b9f8c50da970caa9bee9561c9f12d4e6683.jpeg) ---
**Author:** ![belliott](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/belliott/32/57038_2.png) [@belliott](https://forum.nachi.org/u/belliott)\ **Post date:** [September 30, 2008, 9:53pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/2 "2008-09-30T21:53:54Z")
> [@vsantos](#): > > I’ve never seen this configuration. Dishwasher drain connected just above the trap rather than the disposal. What are your thoughts on this setup? I have no problem with where it is connected, but wish it was bracketed to the underside of the counter,for a reverse trap. ---
**Author:** ![dvalley](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/dvalley/32/206092_2.png) [@dvalley](https://forum.nachi.org/u/dvalley)\ **Post date:** [September 30, 2008, 10:07pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/3 "2008-09-30T22:07:58Z")
I see this set-up quite a bit. Not a big deal. ---
**Author:** ![vsantos](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/vsantos/32/188006_2.png) [@vsantos](https://forum.nachi.org/u/vsantos)\ **Post date:** [September 30, 2008, 10:13pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/4 "2008-09-30T22:13:29Z")
> [@relliott](#): > > I have no problem with where it is connected, but wish it was bracketed to the underside of the counter,for a reverse trap. I’ve noted the lack of a high loop. Thanks for the help guys. ---
**Author:** ![dvalley](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/dvalley/32/206092_2.png) [@dvalley](https://forum.nachi.org/u/dvalley)\ **Post date:** [September 30, 2008, 10:16pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/5 "2008-09-30T22:16:05Z")
> [@vsantos](#): > > I’ve noted the lack of a high loop. > > Thanks for the help guys. The high loop should only be called out if it’s connected to the disposal. The p-trap will take care of the waste connection. ---
**Author:** ![vsantos](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/vsantos/32/188006_2.png) [@vsantos](https://forum.nachi.org/u/vsantos)\ **Post date:** [September 30, 2008, 10:31pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/6 "2008-09-30T22:31:24Z")
> [@dvalley](#): > > The high loop should only be called out if it’s connected to the disposal. > > The p-trap will take care of the waste connection. Wouldn’t water or food being washed down the sink still have the possibility of entering the dishwasher drain particularly in the case of a clogged drain? ---
**Author:** ![lkage](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/lkage/32/347658_2.png) [@lkage](https://forum.nachi.org/u/lkage)\ **Post date:** [September 30, 2008, 11:26pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/7 "2008-09-30T23:26:38Z")
> [@vsantos](#): > > Wouldn’t water or food being washed down the sink still have the possibility of entering the dishwasher drain particularly in the case of a clogged drain? Yes, I’d call it out with no high loop. ---
**Author:** ![belliott](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/belliott/32/57038_2.png) [@belliott](https://forum.nachi.org/u/belliott)\ **Post date:** [September 30, 2008, 11:31pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/8 "2008-09-30T23:31:11Z")
> [@dvalley](#): > > The high loop should only be called out if it’s connected to the disposal. > > The p-trap will take care of the waste connection. David , always call it out , unless you know that particular model has it built into itself. Water always seeks its own level. Thats why some of the guys call out for the airgap devise. ---
**Author:** ![mgratton](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/mgratton/32/58251_2.png) [@mgratton](https://forum.nachi.org/u/mgratton)\ **Post date:** [September 30, 2008, 11:43pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/9 "2008-09-30T23:43:09Z")
> [@vsantos](#): > > I’ve never seen this configuration. Dishwasher drain connected just above the trap rather than the disposal. What are your thoughts on this setup? Vince, I prefer your arrangement to mine… ![IMG_0074.jpg](https://global.discourse-cdn.com/internachi/original/3X/3/f/3fc376642448152bb2b731f1674e078c2ef883a5.jpeg) ---
**Author:** ![jmckee](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/jmckee/32/211009_2.png) [@jmckee](https://forum.nachi.org/u/jmckee)\ **Post date:** [September 30, 2008, 11:52pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/10 "2008-09-30T23:52:58Z")
Vince …that particular fitting is called a dishwasher tailpiece and was designed to be used just as shown…whether they are legal everywhere or not anymore is something i can’t tell you…jim ---
**Author:** ![belliott](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/belliott/32/57038_2.png) [@belliott](https://forum.nachi.org/u/belliott)\ **Post date:** [October 1, 2008, 12:05am UTC](https://forum.nachi.org/t/dishwasher-drain/32362/11 "2008-10-01T00:05:52Z")
> [@mgratton](#): > > Vince, > > I prefer your arrangement to mine… Looks like the bottom of an old cast iron sink. How was the porcelain holding up? Who needs shut offs ,eh Whats up with the black PVC though…is that a new fashion trend? ---
**Author:** ![jgilleland](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/jgilleland/32/1326_2.png) [@jgilleland](https://forum.nachi.org/u/jgilleland)\ **Post date:** [October 2, 2008, 4:57pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/12 "2008-10-02T16:57:01Z")
Marcel hope that DW has a check valve. Did they have a plunger nearby? ---
**Author:** ![jpope](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/jpope/32/59425_2.png) [@jpope](https://forum.nachi.org/u/jpope)\ **Post date:** [October 2, 2008, 7:59pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/13 "2008-10-02T19:59:36Z")
> [@relliott](#): > > David , always call it out , unless you know that particular model has it built into itself. Correct. It doesn’t matter whether it’s connected to a disposal or not, it should have a high-loop or air gap fitting. ---
**Author:** ![mgratton](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/mgratton/32/58251_2.png) [@mgratton](https://forum.nachi.org/u/mgratton)\ **Post date:** [October 2, 2008, 10:59pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/14 "2008-10-02T22:59:18Z")
> [@relliott](#): > > Looks like the bottom of an old cast iron sink. > > How was the porcelain holding up? > > Who needs shut offs ,eh > > Whats up with the black PVC though…is that a new fashion trend? Robert, The sink bottom was holding up OK and shut offs are not required on sinks in my area. They are required at toilet’s and exterior hose bib’s though. That black drain pipe is referred to as _Acrylonitrile Butadiene Styrene_ ABS for short and is very common in my area; PVC is not. What I wanted to bring forward in my pic is that the dishwasher drain pipe is not trapped. ---
**Author:** ![tdietrich1](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/tdietrich1/32/1561_2.png) [@tdietrich1](https://forum.nachi.org/u/tdietrich1)\ **Post date:** [October 2, 2008, 11:07pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/15 "2008-10-02T23:07:48Z")
IMHO, I would comment on the lack of a high loop, and that the DW drain line installed on the garbage disposal, helps keep it clean. tom ---
**Author:** ![jwicklander](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/jwicklander/32/57038_2.png) [@jwicklander](https://forum.nachi.org/u/jwicklander)\ **Post date:** [October 4, 2008, 2:57am UTC](https://forum.nachi.org/t/dishwasher-drain/32362/16 "2008-10-04T02:57:29Z")
Hopefully the Illinois HI’s know that it is illegal in this state to hook up your dishwasher discharge to the disposal. See it all the time, but do you report it? Jeff ---
**Author:** ![kswift](https://avatars.discourse-cdn.com/v4/letter/k/6a8cbe/32.png) [@kswift](https://forum.nachi.org/u/kswift)\ **Post date:** [October 4, 2008, 1:47pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/17 "2008-10-04T13:47:59Z")
High loops are common, but if an air-gap is an anti-bacterial device as well as an anti-siphon device then I guess it’s essential. It’s been my impression that they are recommended by manufacturers, but does anyone know for sure? ---
**Author:** ![jpope](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/jpope/32/59425_2.png) [@jpope](https://forum.nachi.org/u/jpope)\ **Post date:** [October 4, 2008, 8:00pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/18 "2008-10-04T20:00:43Z")
Although they defer to the manufacturers installation requirments, CA code specifically prohibits direct connection of the dishwasher-drain line to a drainage system without a listed air-gap device. ---
**Author:** ![kswift](https://avatars.discourse-cdn.com/v4/letter/k/6a8cbe/32.png) [@kswift](https://forum.nachi.org/u/kswift)\ **Post date:** [October 4, 2008, 11:41pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/19 "2008-10-04T23:41:03Z")
Jeff: Yes, that’s my understanding, but I’ve also been told about some fancy dishwashers in high-end residences that the air-gap is “built-in” or “not required,” etc. I recommend them anyway, and defer to the manufacturer’s specs. It seems to me that bacteria can migrated through a dark tube and on into the “clean” dishes if an air-gap is not present. Having said that, I’ve become woefully aware of my own ignorance on many occassions. ---
**Author:** ![jfunderburk](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/jfunderburk/32/187920_2.png) [@jfunderburk](https://forum.nachi.org/u/jfunderburk)\ **Post date:** [October 7, 2008, 5:17pm UTC](https://forum.nachi.org/t/dishwasher-drain/32362/20 "2008-10-07T17:17:49Z")
Is this ever allowed…connection to the waste line in the crawl space? Obviously no high loop. ![100608-02 075.JPG](https://global.discourse-cdn.com/internachi/original/2X/8/8ae2acbf89ea9a6cc4f73d99487a7a15ccfdbab7.jpeg) [Next page](https://forum.nachi.org/t/dishwasher-drain/32362.md?page=2)