Hi, first post, but I've been casually reading for a while. I've found a lot of good advice here - thanks already!
I'm working on a bathroom, and I'm totally stumped by a vent issue.
Not sure about the best way to attach pictures, so I've uploaded and pasted links below.
There just isn't a good way to get through the roof from this room, so I have an Air Admittance Valve under the sink. After the P-trap, the drain goes into 2" PVC. About 5 feet downstream of that, there's a toilet, which drains into 3" PVC. Then the 3" PVC runs across a room to the main stack with roof vent, which is about 16' away. All is sloped properly so water doesn't pool in the drain lines. The AAV under the sink (rated for 20 DFU) should be adequate to vent both fixtures. However, when the AAV is attached, they don't vent! The toilet doesn't flush all the way (bowl fills up and then drains extremely slowly). When I run the sink wide open for more than a few seconds, it drains slowly and eventually causes the toilet to bubble. However, if I reach under the sink and loosen/remove the AAV, I can feel air rushing in, and everything drains just fine (no sewer gas smell). This makes me think it's a problem with the AAV itself, and not a problem with the rest of the plumbing. So I ordered a different brand of AAV, and the same thing happens! (I've now tried both Oatey and Studor AAVs).
Any ideas? Thanks in advance!
https://drive.google.com/open?id=0B4omjtbz0P0acnNEcTJKQnRRVUd3Rnk3Zk8wVjFuZlpHRUln
https://drive.google.com/open?id=0B4omjtbz0P0acnBoYTZFRmtKZmQzODYzSFdfRHgxTGRaRUtj
I'm working on a bathroom, and I'm totally stumped by a vent issue.
Not sure about the best way to attach pictures, so I've uploaded and pasted links below.
There just isn't a good way to get through the roof from this room, so I have an Air Admittance Valve under the sink. After the P-trap, the drain goes into 2" PVC. About 5 feet downstream of that, there's a toilet, which drains into 3" PVC. Then the 3" PVC runs across a room to the main stack with roof vent, which is about 16' away. All is sloped properly so water doesn't pool in the drain lines. The AAV under the sink (rated for 20 DFU) should be adequate to vent both fixtures. However, when the AAV is attached, they don't vent! The toilet doesn't flush all the way (bowl fills up and then drains extremely slowly). When I run the sink wide open for more than a few seconds, it drains slowly and eventually causes the toilet to bubble. However, if I reach under the sink and loosen/remove the AAV, I can feel air rushing in, and everything drains just fine (no sewer gas smell). This makes me think it's a problem with the AAV itself, and not a problem with the rest of the plumbing. So I ordered a different brand of AAV, and the same thing happens! (I've now tried both Oatey and Studor AAVs).
Any ideas? Thanks in advance!
https://drive.google.com/open?id=0B4omjtbz0P0acnNEcTJKQnRRVUd3Rnk3Zk8wVjFuZlpHRUln
https://drive.google.com/open?id=0B4omjtbz0P0acnBoYTZFRmtKZmQzODYzSFdfRHgxTGRaRUtj
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