QuestionsCategory: QuestionsHow to disconnect stainless steel and threaded galvinized piping connection
Handyman Staff asked 4 weeks ago

I'm trying to disconnect stainless steel drain pipe where it connects to my threaded galvanized pipe so that I can repipe a ptrap for a vanity from the threaded galvinized using pvc.

I'm stuck because I can't seem to pull the steel pipe that is inserted out, despite having loosened what I think is the connection (compression fitting?). I've tried using pliers but I seem to just be deforming the end of the pipe.

Additionally, there's a (brass?) adapter on the threaded galvanized pipe but I can't get it to loosen, despite hitting it with WD40. I'm trying with a plumbers wrench with a rag between the fitting and the jaws.

I'm wondering what other ideas folks might have, or if I'm going about this wrong. (I'm not certain any of my terminology here is correct btw).

My next idea may be to take a grinder a cut the whole thing off, hopefully saving enough threads for a pvc connection. Failing that, my last resort is to open up the wall behind, and cut the section of pipe out from there and in the crawlspace, and then repipe using fernco's to connect to the galvanized.

Below are two photos and my artistic rendering of the situation. I don't know how far the stainless steel pipe is inserted, but it seems further than my finger since I can't feel the end of it.

artistic rendering

side view

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