Thread: dishwasher standpipe

Would like to construct a dishwasher standpipe to get rid of the air gap located at the top of the counter top. I would like to connect the standpipe to the original sink plumbing. Not sure on how to go about this. Pic's would help.

They make some air gaps that double as a soap dispenser, or other similar camouflage, if you're trying to change the look of the thing.

Why not install a new dishwasher with a builtin air gap?
What brand and age dishwasher is it?

Originally Posted by John Kogel

Why not install a new dishwasher with a builtin air gap?
What brand and age dishwasher is it?

I think He is asking about the discharge (drain) side airgap.
It's true, all dishwashers have a built in airgap on the supply side.
But I don't think any have a builtin airgap on the discharge side.

Originally Posted by Rick Cantrell

I think He is asking about the discharge (drain) side airgap.
It's true, all dishwashers have a built in airgap on the supply side.
But I don't think any have a builtin airgap on the discharge side.

I think he wants a "high loop" to replace an air admittance device. The one that looks like a soap dispenser is really an air admittance not air gap. All he has to do is tie the discharge line up to the bottom of the counter top to prevent sink water from flooding the dishwasher in the event of a drain blockage.

Originally Posted by Vern Heiler

I think he wants a "high loop" to replace an air admittance device. The one that looks like a soap dispenser is really an air admittance not air gap. All he has to do is tie the discharge line up to the bottom of the counter top to prevent sink water from flooding the dishwasher in the event of a drain blockage.

"Code in my location calls for either a air-gap or air-break located above the counter top, or the indirect waste piping from the dishwashing machine shall discharge to a standpipe." I need some info on how to construct the standpipe to the original sink drain.

Originally Posted by mark peschmann

"Code in my location calls for either a air-gap or air-break located above the counter top, or the indirect waste piping from the dishwashing machine shall discharge to a standpipe." I need some info on how to construct the standpipe to the original sink drain.

I don't see how you could build a standpipe under a kitchen counter. If this is your home and you have no plans on selling anytime soon and you are not remodeling and need it to pass the AHJ inspection, I would go with a high loop under the sink. The code police are not going to knock your door down. This is an example of an outdated code requirement, IMVHO!

With new dishwashers the discharge line already has a high loop in it, the manufacturers for the past several years have the discharge line going up and over the top of the unit so this automatically places it higher than the sinks flood rim, unless the dishwasher is lower in the cabinet. But as inspectors we still need to report the absence of a high loop if we do not see it under the sink.

Originally Posted by mark peschmann

"Code in my location calls for either a air-gap or air-break located above the counter top, or the indirect waste piping from the dishwashing machine shall discharge to a standpipe." I need some info on how to construct the standpipe to the original sink drain.

How tall must the standpipe be? How high must the bottom of the trap be above the floor? What is the minimum, and maximum, heights of the standpipe above the trap weir?

Additionally, is the kitchen sink next to a wall or is it in a peninsula cabinet? If in a peninsula cabinet is the countertop flat or is there a raise edge behind the sink with a bar-type countertop on it?

There may be some options, but without the above information we probably cannot suggest anything other there guesses based on what we presume the installation is like.