You will be fine with a high loop.

You don't need it. Make sure you mount the high loop properly and frequently air out the dishwasher (just leave door slightly ajar after a load every week or 2).

can't stand dishwasher air gaps. High loop and you'll be completely fine

It’s worth noting that some states have set code for air gaps I.e WA. I still removed mine and the inspector didn’t say anything. Go for it!

I have air gaps. My neighbor has the same model of house with the same model dishwasher, and has the loop. Not sure why they were built differently but works the same.

TIL what an air gap is.

I own a plumbing company. We've never put in an air gap and always just do a high loop. We've never had a complaint or issue that I'm aware of.

My county did...for like 1-2 years. Right as I built.

Perfect. I will be ditching that. Glass washer is much more useful.

I replaced an air gap with a high loop into a disposal. No issues since.

The purpose of an air gap is to prevent a clog in the drain of your dishwasher (at the food processor for example) backing up into the dishwasher and then entering your clean water supply. This is water that you drink from, etc. it does this by having a literal air gap in the drain.

A high loop is still very effective at this, but isn’t as full proof as an air gap. That being said, I still removed mine and replaced it with an RO drinking water faucet.

The reason some houses have them and others have a high loop comes down to where and when they were put in. Some places require it to be up to code, others don’t. My advice: it’s your house, OP. Put your high loop up nice and high and I doubt you’ll ever have an issue.

High loop is fine, though air gap is required by code in some places

Who said the airgap has to go on our counter? Mount it on a piece of plywood right under the counter, above the sink drain.

Well, when the disposal side of your hose clogs, the air gap will be spilling into your cabinet instead of into your sink.

So question (homeowner, not a plumber) - I redid my counters and a new dishwasher, didn't put an air gap in - I routed the dishwasher drain to the disposal, and it loops way up behind the sink and then to the disposal entry. It's secured with zip ties, no issues for 17 years - so is that a "high loop"? (Well, only issue has been coffee grounds in the disposal getting flung up into the drain port and clogging it a bit, but I spoke to the Mrs. about that...)

Yup.

The air gap advantage is that sewage can never get into your dishwasher. I've had sewage backups in an apartment, it spills over the sink sometimes.

If you do not have sewage backing up into your sink due to clogs from upstairs drains, then a high loop is all you need.

If you ever have sewage back up, then it's backed up into the dishwasher (highloop setup) and you will need to run a few sanitary cycles before cleaning dishes in it.

Yup, had to have an air gap on a Renton WA project last year.

>backing up into the dishwasher and then entering your clean water supply. This is water that you drink from

No. Nobody is drinking water from the dishwasher. It doesn't re-enter the water supply of your house.

Contaminated water could re-enter your dishwasher if it doesn't drain properly. The air gap does prevent this, but not for the reason you state.

I'm an appliance technician and installer for the past 15 years. No idea how many dishwashers I've put in but it's.... a lot. I've NEVER done anything but high loop.

There's no way for wastewater from a dishwasher to go back into the supply pipes. It's just to prevent siphoning wastewater back into the dishwasher.

Or every night after it runs

You need to look at the building code before commenting.

Not necessary. I put in an air gap on my dishwasher when I first got my house and read that they were supposed to be better than a high loop. Removed it when I replaced my laminate countertops with quartz and haven't had a problem since then. When I re-ran the drain line after the countertop installation, I noticed the dishwasher had a high loop built into it, so you may not even have to do one yourself.

Any backflow is going to be minimal and will only happen normally when you're putting gallons of water down the drain at once, then will be pushed out the next time you run the dishwasher. As long as you're not putting big chunks of food down the drain, which you shouldn't be doing anyway, you'll be fine.

Hear that? My eyes rolling so hard into my skull. Seriously dude, what difference will a homeowner changing an air gap to a high loop on a damn dishwasher make? Oh, the Humanity, the world will crash down if the county residential code for a dishwasher discharge air gap isn't met. Give me a break.

IPC 2018 removed residential dishwasher air gaps from code. They aren't required in most states

[removed]

IPC 2018 removed air gaps for residential dishwashers

Yeah, there was a discussion a few weeks ago about dishwasher back wash and after looking into it, it seemed like a bunch of states didn't require it. The vast number of different ways that states go about their plumbing codes makes it damn near impossible to discuss code on the internet regarding the United States. IPC, UPC, NSPC, and a bunch of variations based on them, along with some states using code per municipality. You may as well pile into a clown car as to try to give advice based on code over the internet. That's where my facetious comment above came from. I see so many folks citing code here that may or may not be relevant to where someone lives. It gets old.

Especially after OP states in the original post "it is no longer code where I live" 😂

This is my understanding as well. Nothing to do with the pumped wastewater reentering the dishwasher.

What I'm confused about is, doesn't every dishwasher have a check valve on the drain pump outlet, or in the drain hose?

I don't think a dishwasher can have a check valve as they are designed to remove food particles. A check valve might get clogged pretty quick under those use conditions.

I'm talking out of my ass ofcourse, some models might have those valves since some models have a built in high loop. But code is code, and it's meant to protect the average user. I think the manufacturer would have to send a lobbyist to ask every state, city, and township to update their code as well.

interesting. I know for certain my Bosch has a check valve, but it also has a metal mesh filter to prevent food particles from ending up in the sump.

I am not a plumber but I did get a new sink and reinstalled my dishwasher with a new water line, P-trap, disposal, and high loop. Haven't had any issues.

I did a high loop. My dishwasher even came with the hose thing that holds the high loop.

It's under the sink. So it goes out the dishwasher low through the sink cabinet sideways. Then up high loop as high as it will go under the actual sink, then back down in the garbage disposal.

Also the best practice is to make sure the disposal is clear of anything while you run the dishwasher so it can drain without issue.

Also put a little detergent in the washer area (not the enclosure) so it will wash during the prerinse

I like the jive of your jinb!

And you need to read the OP

> it was code here for a whole year or two. It no longer is.