Mysterious Vent Pipe under Double Kitchen Sink

[pecassidy07]

Hi,

Plumbing idiot seeking advice. I replaced my strainer baskets in my kitchen sink and the pvc nut connecting the drain pipe to the strainer basket on the right sink doesn't thread onto the strainer basket threads; it also doesn't line up to the strainer basket opening very well. I cannot loosen the p-trap or anything below it because all the PVC pipe from the entrance to the p-trap down is glued together. This led me to the following questions:

1. Should I cut the PVC pipe leading down into the basement/septic and just rebuild the whole system?

2. Should I just replace the PVC pipe and locking nut on right sink and hope it lines up correctly?

3. Why is there a vent pipe going nowhere and uncapped under the sink?

Pictures attached!

Thanks in advance for any wisdom you can offer!

Regards,

Patrick

 

[CT18]

Loosen everything and try and thread to the strainer first. You could cut that 2" riser and start over with a jamb nut trap and that would allow you some flexibility.

 

[FishScreener]

The vent to nowhere appears to have an air admittance valve on the end.
When you put in the new strainer it probably moved it slightly, and it no longer is aligned with the riser.

Two options: First is to remove the strainer, put new putty under it, and get it started on to the waste line before you tighten the retainer ring. Second is to cut off The trap and line just above the sanitary tee, and get a trap assembly which isn’t glued in. That would let you rotate and align things so that you get it lined up with the tail piece.

 

[pecassidy07]

Loosen everything and try and thread to the strainer first. You could cut that 2" riser and start over with a jamb nut trap and that would allow you some flexibility.

CT18,

Thanks for the response! I'm going to cut just below the sanitary tee and rebuild the system using a jamb nut trap as you stated.

 

[pecassidy07]

The vent to nowhere appears to have an air admittance valve on the end.
When you put in the new strainer it probably moved it slightly, and it no longer is aligned with the riser.

Two options: First is to remove the strainer, put new putty under it, and get it started on to the waste line before you tighten the retainer ring. Second is to cut off The trap and line just above the sanitary tee, and get a trap assembly which isn’t glued in. That would let you rotate and align things so that you get it lined up with the tail piece.

FishScreener,

Thanks for the response! I think your right about the vent pipe but their is no admittance valve on the end. I plan on adding one when I rebuild the system with a p-trap that's not glued in

 

[pecassidy07]

CT18 & FishScreener,

Thanks for the advice! Cut the riser just below the old sanitary tee, cemented a new sanitary tee, then replaced the whole system with slip joint drain pipes. No leaks and easy to plumb to the strainer baskets. Finished product cost only $39.

 

[TomFOhio]

You did a nice job on the piping. As I look at your picture it think you put what we call a cheater vent for a mobile
home. A good and correct AAV cost as much as what you spent so far.

 

[pecassidy07]

TomFOhio,

Thanks for the insight! I did opt for the $8 AAV vs the $28 one at my local hardware store. I plan on raising the AAV up to the waterline of the sink basin and I'll monitor the cheap AAV. Probably will replace it with a pricier Studor AAV within a year if I don't have any issues between now and then.

Regards,

Patrick