Is the installation of a dish washer air gap above the counter a code requirement in Huntington Beach California? I would like to eliminate as many above counter items as possible in my new kitchen installation with granite countertops and undermount stainless steel double sink.
Can the dishwasher discharge hose be air-gapped directly into the sewage vent pipe? Currently the kitchen walls are open and such an installation can be made.
Thanks for your help.

iamgrowler

Your local municipality has adopted the 2003 Uniform Plumbing code, so if you are having the job inspected, then yes, you do need an air-gap.

However, if the walls are already open, then you might consider having a Johnson Tee installed instead of a counter mounted air-gap.

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doug238

down yonder here in da south we do not use that air gap thingy. we use the southern building code congress [sbcc] code book and they [the older guys] use a separate trap either under the floor if it will be accessable or in the cabinet under the sink and connect directly to the trap, making sure the drain hose loops up to the bottom of the countertop. we [the not so older guys] do the same loop but we tie the drain hose either into the 1" branch on the disposer [making sure to remove the plug] or into the waste piping under the sink before it goes into the trap.
that pic growler posted wuz sum purty workmanship, but how do ya clear it if the 1/2" gets clogged?

iamgrowler

Funny you should ask that -- This afternoon I spoke with an inspector who is trying to push through an increase in size to at least 3/4".

Of course the manufacturer of the device won't hear a word of it, and once a precedence has been set....

As for cleaning the line out -- I've installed at least a thousand of them, if not more, and cleaning them out has yet to come up.

The biggest issue with these is making sure you use long sweep 90's instead of 'close ruff' 90's when dropping down to the cabinet base.

doug238

[strains eyes and peeks closely at 1/2" elbows in pic] [grinz]
it sure is some purty work.

letmetellu

I have a question about the picture, is the 1/2 inch copper pipe connected into the plastic with or without an air gap, and if it is without an air gap what keeps this from being a cross connection. If it is installed with an air gap where it enters the plastic what is going to keep that joint for leaking if the ABS stops up.?

doug238

i would suppose it is not considered a cross connection because it is a dishwasher drain hose connected to a house drain system. there are 2 solenoids between the potable water supply and the house drain system. one on the inlet water at the connection and one at the bottom of the dishwasher at the connection of the hose.
[peeks in code book]
sbcci code book page 26 and 27.
409.2 water connection- the water supply to a dishwashing machine shall be protected against backflow by an air gap or backflow preventer in accordance with section 608.
[comment] i think that is done by the appliance manufacturer on the side of the dishwasher.
409.3 waste connection- the waste connection of a dishwashing machine shall comply with section 409.3.1 or 409.3.2
409.3.1- domestic dish washing machines- domestic dish washing machines shall discharge indirectly through an air gap or air break into a standpipe or waste receptor in accordance with section 802.2, OR discharge into a wye branch fitting on the tailpiece of the kitchen sink or the dishwasher connection of a food waste grinder [that would be ya disposer] . the waste line of a domestic dish washing machine discharging into a kitchen sink tailpiece or food waste grinder shall connect to a deck mounted air gap OR the waste line [drain hose] shall rise and be securely fastened to the underside of the sink rim or counter.
409.3.2 commercial dishwashing machines........
[interpretation mine] if ya connect the drain hose to a tailpiece on the sink waste or to the disposer branch AND loop the hose up to the height of the bottom of the countertop ya don't gotta have an airgap. the pic does not connect as such and neither did i see an airgap. but it sure is some purty work.
[considers a nap]

iamgrowler

It does have an air-gap, the first picture was found on the net and was not a very good representation.

Here are some pics of a recent installation, the craftsmanship is somewhat dubious, and the installer has been chastised.

The part you see going through the plywood is the air-gap, and has a round, perforated trim piece that is open to the atmosphere.

As for the standpipe backing up, this has never been an issue in all the time I've used them, bear in mind that the 1/2 copper tube is similar in diameter to the dishwashers drain hose, which is 5/8 I.D.

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iamgrowler

Acceptance and use of the Johnson Tee is unique to areas where the Uniform Plumbing Code has been adopted, which is pretty much the entire West Coast and parts of Alaska.

When I first joined the forum I would dive in on all of the rough-in questions, but it became apparent after about two weeks that my advice, while goodly intended, was usually wrong.

The UPC, which is what I learned, bears little resemblance to the IPC or SPC that most of the US has adopted, so unless they specify they are from the West Coast, I tend to butt out of the rough-in threads altogether.

afiore

Thank you all for your comprehensive answers to my question. My research of the applicable code, California Plumbing Code 2001 section 807.4, seems to authorize an air gap or a high loop of the discharge hose under the counter, but it appears that many municipalities in California have eliminated the second option. I have not been provided with the documentation of it, but it appears that Huntington Beach has also eliminated the second option. I do not want to press the issue with the city so I will just install an air gap. Blanco has a nice looking dishwasher air gap in stainless steel.
Thanks again for your help.