Hi folks - apologies in advance for what you may find is a dumb question. I've got a sink in a 2nd floor bathroom that's plugged. took the P-trap off and the trap was fairly clean...but when I looked into the drain connection in the wall, you can see water standing in the drain pipe inside the wall. The bath tub located next to the sink drains fine...and i'm assuming they share a common drain pipe heading downstairs. If true, I'm guessing the plug is not too far below where the sink drain goes into the wall.
Here's where I'm a little confused: when I was looking into the drain line in the wall, I could see the connection was a tee: one branch going down and the other going up. I'm assuming the part going up is the vent line. What I also noticed though was that there's another line that tee's off of the sink drain just above the p-trap. Looks like about 3/4 inch PVC that runs pretty much horizontal, makes a 90 degree turn, and then heads into the way. What the heck is this? I'm guessing it's another vent line??? Is this a normal practice???
Because it runs horizontal for about 12" then turns 90 degrees and runs another 12" horizontally, I'm guessing it's prone to clogging also (once the sink drain starts backing up)??? I'm attaching some pics that hopefully show what I'm seeing...
Thanks in advance for any explanation...
Here's where I'm a little confused: when I was looking into the drain line in the wall, I could see the connection was a tee: one branch going down and the other going up. I'm assuming the part going up is the vent line. What I also noticed though was that there's another line that tee's off of the sink drain just above the p-trap. Looks like about 3/4 inch PVC that runs pretty much horizontal, makes a 90 degree turn, and then heads into the way. What the heck is this? I'm guessing it's another vent line??? Is this a normal practice???
Because it runs horizontal for about 12" then turns 90 degrees and runs another 12" horizontally, I'm guessing it's prone to clogging also (once the sink drain starts backing up)??? I'm attaching some pics that hopefully show what I'm seeing...
Thanks in advance for any explanation...