Re-plumbed my "S" trap!

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Looks good.

However.

Sometimes, in that configuration, the disposal can pump waste water right across into the other sink drain, and it can shoot up from the drain or partially fill the sink.

If that happens, changes can be made.
 
Looks good.

However.

Sometimes, in that configuration, the disposal can pump waste water right across into the other sink drain, and it can shoot up from the drain or partially fill the sink.

If that happens, changes can be made.

Actually that does happen. It happened before the switch and it still happens, although not as bad. It only happens when I put on the disposal on. Water used to shoot out the drain like 3 feet now it just comes up. Still annoying is there a way to fix that?

Also I get a foul smell when the dishwasher starts. I suspect this is the water backfeeding into the line but I don't know how to fix that either. I have the high loop and all with the dishwasher drain. The old S trap I had plumbed the dishwasher into the main sink drain using a dishwasher tail piece. On the replumb, I connected it to the disposal (punched out the blockout plate) so I can't go back to the other method.
 
The dishwasher stink is because food particles can decompose in the drain line.
Then they drain into the disposal, mixed with warm water, which lifts that stink right out of the disposal opening.

You can try running the dishwasher more often.
 
The dishwasher stink is because food particles can decompose in the drain line.
Then they drain into the disposal, mixed with warm water, which lifts that stink right out of the disposal opening.

You can try running the dishwasher more often.

We run it at least once a day many times twice. It also was never in the disposal until this replumb. The force of water coming out the drain is considerable so I don't think there is a blockage anywhere. I wonder if this has anything to do with the water fractionation I fixed by running the shorter cycle. I cleaned up everything (all the gunk) but maybe there is some of that garbage in the drain lines. It's been 6 months so my inclination is that it should be clean by now. There is an extension hose on the dishwasher drain as well since the dishwasher is a half a cabinet away from the sink so the included drain was a little short.
 
Experts here can advise on both issues, the disposal flooding the opposite sink, and the dishwasher drain line stink.
 
Yeah I was afraid you were going to say that. I have been putting the re-route of the dw drain off because the sink base is actually a corner cabinet. Then to the left there is a 1/2 cabinet, then there is the dishwasher. So in order to run it high, I would need to fish it through the blind part of the cabinet. Not terribly hard (I used to fish network cable) but not super easy either. I'll get on it though it needs to be done.
 
That center tee in my setup does have a baffle. The way you pictured is the way I originally was going to plumb it. The problem is the moronic way the hot and cold water lines come up from the floor. They are directly in the way of doing it that way. It also is not as easy as your picture due to one of my sinks being higher than the other (the one with the garbage disposal). I had considered cutting them and running them back and up but was not looking to make this project more complicated than it had to be.

Before the re-plumb water literally shot out 3 feet from the drain in the larger sink bowl when the garbage disposal was turned on and it was full of water. It doesn't do that unless it has a lot of water in it. Since the replumb it isn't much some water will come up if the disposal is full but doesn't shoot out at all and fairly quickly drains down.
 
Put the disposal drain plug into the sink strainer on the other sink, it has a fairly tight rubber seal, and might hold back the drain water trying to escape into that sink.

Or put the disposal drain plug in the other sink, then add a few inches of water.
The weight should hold the seal down, keeping the yuck water from pushing up into there.
 
The water coming up isn't that bad as to have to do something about it. And it only occurs when the disposal side fills with water before you turn on the disposal. Otherwise everything drains as it should. I am going to take off the disposal drain (I didn't during the replumb) just to see if there is some blockage in it. Seems like it fills with water more than it should for the small amount of food waste that is put in it. It almost seems like it is getting some sort of air lock in it at times. When I turn it on it always drains down quickly though and that is also when I get some water coming up in the other side.
 
That AAV isn't helping when that disposal drain is pressurizing the piping contents. Not saying you should change it but I bet if it was a piped vent, it would be less apt to blow it up the other sink basin.

But if you ever do re-pipe things, I would suggest mounting that AAV as high as possible, while leaving enough clearance to allow it to be replaced, if need be.
 
That AAV isn't helping when that disposal drain is pressurizing the piping contents. Not saying you should change it but I bet if it was a piped vent, it would be less apt to blow it up the other sink basin.

But if you ever do re-pipe things, I would suggest mounting that AAV as high as possible, while leaving enough clearance to allow it to be replaced, if need be.

I added the AAV per advice of a plumber. This is already a properly vented drain with an open roof vent.
 
I added the AAV per advice of a plumber. This is already a properly vented drain with an open roof vent.
Oh! Okay. My thought was that the AAV close's when subjected to a little pressure, while the piped vent is open to flow in either direction.

Another thought that just came to mind is the fact that those 2 basin drains join together in a tee of the same size and doesn't increase in size until after the tee. I would think increasing the tee size would help the combined flows and/or some of that restriction going down.
 
Oh! Okay. My thought was that the AAV close's when subjected to a little pressure, while the piped vent is open to flow in either direction.

Another thought that just came to mind is the fact that those 2 basin drains join together in a tee of the same size and doesn't increase in size until after the tee. I would think increasing the tee size would help the combined flows and/or some of that restriction going down.

Ha! Good luck finding all the parts to do that. All I could find were these "standard" 1 1/2" "sink" parts. You can see I used adapters where I could to switch to actual plumbing pieces.
 
Only thing i see is the AAV looks a tad low to my eyes
If you were to cut the pipe below the AAV.
then add a 2'' tee. with a CO
then reinstall the AAV on top of that'
I think you will thank me if you ever have to snake that drain.

Your advice is sound but I thought about raising it up and figured the main reason it would matter is if there should be a clog in the actual drain downstream of my last fitting (the one the AAV is on top of). In that case, the AAV could flood unless it is above the level of the sinks, which I don't see any way to get that high there just isn't room. But since it is a threaded fitting on the AAV (meaning it could also act as the cleanout) it would be a simple matter to unscrew it to raise it up a bit. That thing behind it is the control for the motion activated faucet, which was installed before the replumb. I'd have to move that over too.

Doesn't matter it'll never clog it is septic and the tank is a good 20 feet vertical below the AAV level.
 

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