How concerned should I be about this?

Someone remodeled my bathroom. New copper pipe and pvc drain to replace galvanized. New cabinet put in... old galvanized water lines abandonded in wall.

From the basement I can see the inside of the wall from a small crevice. I can see where the cast iron elbow for the old drain goes into the drywall. Unfortunetly from the bathroom there is a new cabinet and plumbing blocking its entrance way.

I can follow the old galvanized pipe to where it connects to the my main cast iron drain. It connects to what looks like the vertical vent stack of my system (I assume this mean it was "wet vented"?)

Anyway, my concern is I cannot see behind the cabinet and tell if that elbow (or a nipple if one is attached) is capped or plugged.

It would take removal of the cabinet or at the very least cutting it to know for certain. I assume the new cabinet butts up against the drywall and the elbow or stubout.

Is this something I need to investigate? Ie: the abandonded drain line still be connected to the stack but not capped or plugged?



Edited 2 times.

Well I went from "How concerned should I be" to "How to fix it"

I was able to get access to the nipple sticking out of the wall from inside the cabinet by cutting a hole.

The nipple is deformed, I wouldn't be able to screw on a cap. Someone shoved a rag and paper back into it to "seal the hole"....

I cannot remove the nipple as I do not have sufficient room to wrench it off if it will even budge.

How do I seal this hole? Can I plug it with silicon?

try a 'jim cap'

if too deformed you will need to cut it back with a sawzall



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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Turns out (after an hour under the sink) that someone did plug the elbow with some sort of caulking material. I guess they weren't total @#$%&. They stuffed a rag into the nipple and installed the cabinet over it.

Overkill probably, but I plugged the nipple with silicon (there was no budging it) and then put on a "jim cap" as you suggested on the end. (I had one in my spare parts box, didn't even have to go to the hardware store for this one!!)

Hopefully that is sufficient and what a plumber would do??



Edited 1 times.

good 'nuff for 50 years

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638