Air addmitance value delete question

[TT_Vert]

Air addmitance valve delete question

We just put in a new single drain sink and a garbage disposal. The issue is the air admittance valve that is there right out of the wall sets the P trap too far and in fact the 90 out of the air admittance valve hits the garbage disposal. I was curious if this is something that is necessary which is why they put it in or perhaps something they added just because? I don't have the ability to move that valve any closer to the back of the cabinet as it's already as far back as it'll go. I think deleting It is my only option. What is your experience/opinion here?

I attached two pics. One before I took the Y out which went to both old sink drains and one after I removed that and debonded it. I cannot get a 90 in here w/o hitting the disposal unless I remove that AAV.

The device in question is a proflow ESR 1664
Thanks
Dave

 

[bobbyjean]

do you have city sewer or septic? grinders make for plugged drains ......of course this depends on whats put in to it.
what size pipe is that..guessing 2 inch... you can repipe that aav ...you would need to get the ty off first though...do you need it? maybe...your trap will be 1 1/2 with swivel joint...i used a flexable drain kit from amazon awhile back...will try to find link for you

 

[tigeraid]

IMO, garbage disposals don't do anything but plug up yer ****. And I would assume it would make things much worse if you don't have the sink properly vented (and therefore, properly draining.) But do as you will.

What Git said is correct, though, the valve must be 4-6" minimum above the center of the trap arm, on the drain line, otherwise it won't function at all.

EDIT: like zo.

 

[TT_Vert]

The valve is at least 4 inches above the P trap. Probably 8. I am on septic and I'm not sure why they installed this. Perhaps there is no vent for this drain. We don't throw much stuff in the disposal but the wife wants one so she's getting one. This one has some type of add on liquid dispenser that is supposed to help break down things in a septic tank. The pipe is 2", what is a "ty"? I was thinking of removing the AAV, putting a 90 it followed by a T for the AAV and then another 90 to the disposal.

Thanks
Dave

 

[oldcpecdr]

Septic system and garbage disposal...... taking out garbage free, septic system maintenance or replacement expensive......

AAV is necessary if there is no external air vent...

 

[vavet]

Our setup is similar to yours. We have a septic and a garbage disposal. We're careful about what we put down the disposal or flush. We were on county sewer at our previous house - I used to put egg shells down the disposal. I don't do that now. Food scraps big enough to be scraped in the trash get scraped. It's really only the food that is on the plate after scraping that goes into the disposal.
Is your sink on a peninsula or island? Is there a wall behind the sink area? Usually it is those setups that have the AAV instead of the vent going through the roof.

 

[strutaeng]

Re: Air addmitance valve delete question

We just put in a new single drain sink and a garbage disposal. The issue is the air admittance valve that is there right out of the wall sets the P trap too far and in fact the 90 out of the air admittance valve hits the garbage disposal. I was curious if this is something that is necessary which is why they put it in or perhaps something they added just because? I don't have the ability to move that valve any closer to the back of the cabinet as it's already as far back as it'll go. I think deleting It is my only option. What is your experience/opinion here?

I attached two pics. One before I took the Y out which went to both old sink drains and one after I removed that and debonded it. I cannot get a 90 in here w/o hitting the disposal unless I remove that AAV.

The device in question is a proflow ESR 1664
Thanks
Dave

The AAV is installed horizontally? I didn't know you could do that. Here's the spec. sheet:

https://api.ferguson.com/dar-step-service/Query?USE_TYPE=SPECIFICATION&PRODUCT_ID=4146469

It looks like it needs to be installed upright? I can't answer the question as to why you have it or need it, but you can just re-rout it to accommodate what you reconfigured.

 

[TT_Vert]

It is vertical. I am also trying to find out if it has to be inline with the drain or if I can Tee off and have it off to one side of the Tee. I'm not sure if it just has to introduce air or if it must be inline w/ the drain from the sink itself.

 

[strutaeng]

Ok, I see it now. What is behind that wall? Hopefully not an exterior wall?

Can you cut the back wall and run a real vent to the roof? I know that's a lot of work, that's the correct way to do it. The AAV was likely added because that's all they had. Look for vent jacks on your roof. Maybe you have one close by to tie into?

I would lobby not removing it. I would think you can tee off to the side to get clearance and re-install it vertically as you have it.

 

[flat350]

If you run your line with the wye first at the wall and then a tee at the end with the AAV it will almost be like the drain is circuit vented and it will probably work OK.Look at pg 17 below.


https://ipscorp.com/pdf/studor/Studor_Technical_Manual.pdf

 

[TT_Vert]

Thanks guys. I need to read those docs more. I realize I don't know enough about this to remove it so it will stay. It is in a peninsula which is why they probably did what they did. I just need to determine if I can have one side of the T contain just this AAV and the other end the feed from the sink. I am very tight for space between the wall and the disposal so I cannot use a Wye. I have to Tee right out of the wall. I was going to go left w/ the AAV and right for the drain from the GD. I'm having a plumber come out though as the drain height is too high for the GD and it would never actually function. Pesky gravity. I don't want to be the one to cut the cabinet/drywall and shorten the pipe. The other way I considered was an elbow out to a T which would have the AAV. I'll let the plumber figure it out and I'll report back with what he does.


Dave

 

[Moose97]

If an AAV is installed you can bet it isn't vented to roof. Removing it will just cause more problems.

 

[TT_Vert]

If an AAV is installed you can bet it isn't vented to roof. Removing it will just cause more problems.

I'm sure you are right. The more I research and understand that is probably the case. I'd never seen one until yesterday. Had to google the PN.

Dave

 

[flat350]

Thanks guys. I need to read those docs more. I realize I don't know enough about this to remove it so it will stay. It is in a peninsula which is why they probably did what they did. I just need to determine if I can have one side of the T contain just this AAV and the other end the feed from the sink. I am very tight for space between the wall and the disposal so I cannot use a Wye. I have to Tee right out of the wall. I was going to go left w/ the AAV and right for the drain from the GD. I'm having a plumber come out though as the drain height is too high for the GD and it would never actually function. Pesky gravity. I don't want to be the one to cut the cabinet/drywall and shorten the pipe. The other way I considered was an elbow out to a T which would have the AAV. I'll let the plumber figure it out and I'll report back with what he does.


Dave

I see your in Illinois,if the plumber that comes by uses a tee it will not be done per Illinois State code,horizontal fittings need to be long sweep which a tee is not.See my sig below,retired after doing plumbing in Il. for 45 years.If he has to lower the drain just put the AAV in the wall with an access panel and pick up some space in the cabinet.I was just up that way today off Bonner Rd. and Fairfield looking at a house that a nephew bought.

 

[DieselNut88]

I dont believe aav are code in illinois. You need some kind of loop vent.

 

[TT_Vert]

That is odd, just had the house inspected prior to purchase. Actually two separate inspectors. Figured one would catch it if it was not up to code. it is VERY well hidden behind the bowl of the sink though so they'd have to be on their back to find it.

Dave

 

[flat350]

I dont believe aav are code in illinois. You need some kind of loop vent.

I'm positive that they do not meet code in Il.,not really called a loop vent it's just call an island vent.

ection 890.1600 Special Venting for Island Fixtures



a) Traps for island sinks and similar equipment shall be roughed in above the floor and shall be vented by extending the vent as high as possible, but at least the drainboard height, and then returning it downward and connecting it to the horizontal sink drain immediately downstream from the vertical fixture drain. Back-to-back island vented fixtures shall meet the requirements of Section 890.1480(b).



b) The returned vent shall be connected to the horizontal drain through a sanitary drainage fitting and shall be provided with a vent taken off the vertical fixture vent by means of a sanitary drainage fitting immediately below the floor and extending to the nearest partition and then through the roof to the outside atmosphere, or may be connected to other vents at a point at least 6 inches above the flood level rim of the fixture served. Drainage fittings shall be used on all parts of the vent below the floor level, and a minimum grade of ¼ inch per foot back to the drain shall be maintained. The returned bend used under the drainboard shall be a one-piece fitting or assembly of a 45 degree, a 90 degree, and a 45 degree elbow in the order named. (See Section 890.1340 and Appendix K.Illustration GG.)



(Source: Amended at 38 Ill. Reg. 9940, effective April 24, 2014)

 

[TT_Vert]

So how does one w/ an island install a sink?

Dave

 

[flat350]

With an island vent,drawings and description are provided in the State Code book which are even available for viewing and download online at the IDPH website.The drawing doesn't want to show up when I copy and paste.



Appendix K
Section 890.ILLUSTRATION GG Special Venting for Island Fixtures



(Referenced in Section 890.1600(b))







(Source: Amended at 38 Ill. Reg. 9940, effective April 24, 2014)

 

[TT_Vert]

Found it thanks. Looks like a loop that wyes into an existing vent stack?

Dave

 

[PassnThru]

It has to have air to drain.
It has to get the air from a place that it cannot stop up and push water through.

 

[TT_Vert]

Thanks guys. Plumber came today and lowered the drain for me. Retained the
AAV in a T after an elbow out of the lowered drain. All seems well thus far.

Dave