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 AAV question, washer drain
Author: WilliamF (OH)

Will try to make this a short story about the situation which I know is not ideal.

We bought a house that we got a good deal on, remodeling it slowly because we still have our current home. Now we got a great deal on our current home but have to get out very quickly in order to take it. In our new home remodel we had plumbers move the washing machine drain to the other side of the laundry room a while ago.

I later found out that it was done improperly. It is 15 feet away from the stack and has no other venting. I also just realized it doesn't have any slope to the stack.

I asked about this problem a while ago here, and pretty much planned to just have a good plumber come out and redo it with proper venting. Problem is I had about 5 plumbers look at it and all but one said to leave it as is other than just fixing the slope of course. The one other said he could just put in a AAV. So for now I am just going to put in a AAV myself and fix the slope.

My main question is just the best placement and connection to of the AAV. How far away from the trap? Currently the trap is under the floor, but is accessible and have heard people say it should be above, some say it is ok below. For now it will just have to stay below because of the configuration above. But with the trap being below the joist I can still have the AAV above it. Front loading washer, so at least it will be less water.

Just wondering how far away, and the type of connection from the pipe upto the AAV.

This is what I was thinking: [i51.photobucket.com]

Pipe is 2" and I have about 13 inches of room to go up between joists above the top of the trap

I do plan on having this redone by a plumber or myself with proper venting at a later time, I just need this to work because we need to get our washing machine moved to this house within the next few days and need this to work even if it isn't ideal for now. My fault for not having this fixed one way or another all this time, but I can't change that now.

Appreciate any help

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 Re: AAV question, washer drain
Author: Racer814

does the standpipe overflow when the washer drains?....does it go down fine but gurgle?....do you smell sewer gas after you use it?....is the stack a vent stack?...or a drain?..the aav isnt going to address the issue of no slope but it may keep your trap from siphoning....definitely a short term solution at best....aav's don't work well on washing machine drains....in fact I think they are overused period, but may help here for the time being....get a reputable plumber(one that won't tell you to leave it like it is).....15 ft from the vent is too far and you need 1/4 " per foot drop on your drain

Edited 1 times.

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 Re: AAV question, washer drain
Author: e-plumber (NY)

Some areas here do not allow AAV's on washing machine drains at all. And yes it is your fault for allowing work to be done in your home without making sure that it was filed and inspected.

This time do it the right way, hire a licensed Plumber and have the work done according to your local code.


"The society which scorns excellence in Plumbing as a humble activity and tolerates shoddiness in philosophy because it is an
exalted activity will have neither good Plumbing nor good philosophy: neither its pipes nor its theories will hold water." -
John William Gardner 10/8/1912 - 2/16/2002

Repair your leaking Plumbing fixtures ASAP [www.theplumber.com]
This slow drip will waste 7+ gallons of water per day.

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 Re: AAV question, washer drain
Author: redwood (CT)

An AAV is all to often the lazy plumbers or, handyman's way of venting. It is and always should be a vent of last resort and should never be used on a drain for a pump discharge.

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 Re: AAV question, washer drain
Author: WilliamF (OH)

I realize it isn't the best way and I did say it was my fault for not having it done correctly. I had no idea at the time what needed done, I hired a plumber that was referred. I wouldn't have let it go if I knew what was suppose to do be done. The other 5 that have come to look have said it is fine, so I'm not going to pay a plumber to fix it based on what I say. I also wouldn’t be sure if they tied into another vent correctly, etc.

The fact is I can't change that now, and the washing machine has to be running within 2 days. I will not have time to find someone and have the work completed since I have called most of the people in the phone book already to have it done.

It would be a temporary solution for now. I can install the AAV at least and be able to run the washing machine.

I was just hoping to know the best configuration for it for the time. Distance away and the type of connection from the pipe to the AAV. Was assuming combo but thought I would make sure.

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 Re: AAV question, washer drain
Author: jawar

just keep in mind that ohio code states that your trapneeds to be 2" and that you can only go up to 6'awayfrom your trap.what part of ohio are you from

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 Re: AAV question, washer drain
Author: WilliamF (OH)

the trap and all pipe is already 2", so that isn't a problem.

i am guessing that just means the avv/vent needs to be within 6'

and i am in north east ohio.


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 Re: AAV question, washer drain
Author: hj (AZ)

If it is like most situations, once the washing machine is connected and working, the vent installation will be pushed to the bottom of the "to do" list, AND STAY THERE.

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 Re: AAV question, washer drain
Author: WilliamF (OH)

Most likely right about it being put on the todo list. Fact is though we need a washing in here running by Wednesday.

Going to add a AAV with combo about 2 feet from the trap, fix the slope, and cross my fingers. Figure it can't be any worse than it is and 5 plumbers have told me to leave it. At some point it will be done correctly either by a plumber I find who knows what he is doing, or I will figure it out and bring it up through the closet wall

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