AAV for washer and toilet

[mom2]

My husband installed an AAV in the wall to vent our washing machine and toilet. He installed the wye backwards and I'm worried the washer won't drain properly... he is an electrician not a plumber!! --Do I need to redo this?? Any advice is appreciated! --Worried wife

 

[Mr_David]

the AAV is useless for the laundry drain.
If it wasn't dumping into a toilet vent the last 90 turning down should be a santee with the AAV on top of the tee
the Laundry should not be dumped in to the toilet vent.
You're gonna end up with suds on your bathroom floor or the laundry may suck the water from the your toilet bowl.

Drop the p-trap down closer to the floor

 

[mom2]

It was originally just the washer drain that connects into the toilet...but he didn't vent the toilet and that's the only place available to add a vent, short of tearing the floor and everyth ing apart. I have a low water H.E. washer so I'm hoping that helps with the suds issue? I've done a couple loads of laundry and no mess yet.. The Ptrap was originally right above the floor.. I have no idea why he moved it up. Do you think it will work if I just lower the Ptrap, or am I doomed either way? Tried to convince him to do it correctly and use 2 inch pipe and all but he won't listen.. looks like I'll do it myself or call a plumber while he's at work.

 

[CT-18]

Plus there is a good chance that trap will be pulled dry the way he has it set up. He has basically made a S trap and the velocity that machine is draining it could siphon the trap seal out.

Those AAV's need to be accessible after in case they fail.

 

[Zanne]

A few things

1. As CT-18 pointed out, your husband has created an S-trap. The trap arm on a 2" vent pipe needs to be at least 4" long (it must be no less than two pipe diameters) and no greater than 6' (under IPC-- I believe it is shorter under UPC). The trap arm will need to slope downward at 1/4" per foot. S-traps allow water to be siphoned from the trap which allows dangerous sewer gases to come up through the drain.
2. AAVs have a dfu (drainage-fixture-unit) limit. You need to know the max dfu the AAV can handle. You also need to see how many dfu rating each fixture is. There is a chart somewhere but I can't seem to locate it. I think it is 1.5dfu per gpm (gallons per minute) of the unit. For example, my washing machine can move 6gpm and would have a dfu of 9. I suspect both washing machine & toilet would exceed the supported dfu limit of the AAV.
3. AAVs are not allowed inside the walls unless you have a vent box/access for them. They need atmospheric venting-- access to free airflow to work properly. In addition to needing airflow, you need to be able to access them for replacement in case the diaphragm fails. Something like this in-wall box with vent cover.
4. I do believe you would need a sanitary tee instead of a wye because the wye does not allow the air to flow to the vent.
5. Washing machine standpipe trap arm should be between 6" to 18" above the floor-- I can't tell whether or not yours is higher bc I suck at judging size/distance.

I am not a plumber, but I have been looking things up because I need to do some work on my home. So, if the actual plumbers disagree with me, listen to them.

 

[Matt30]

Definately needs a full do over. Sparky likely made things worse than what was originally there. Hopefully someone can do up a diagram for him to go by, I'm no good with internetting

 

[Zanne]

Is the toilet on the other side of the wall?
A sketch of where things are and the distances might help.

This doesn't solve the issue of wet-venting the toilet, but the goal is to give you a better idea of what it should look like.