Connecting a new drain line to an old wye fitting

[cdetorie]

I need to connect a new 3" drain line to a previously-existing ABS wye fitting. The wye joins a horizontal pipe to a vertical pipe, and the third opening of the wye ends in a threaded cleanout plug. My plan is to remove the cleanout plug and replace it with a male threaded adapter, then connect the new drain pipe to the adapter. Is this an acceptable plan? Or does the code or "best plumbing practices" make this unacceptable? (Or, perhaps the threaded male adapter I'd need doesn't exist! )

 

[frodo]

It is unacceptable because of the threads.

a sewer system is designed to carry the waste off in a smooth pipe. that is the reason the inside of the fittings are made like they are.

when properly fitted together their are no humps or crevices. it is called the burnham system



those threads are going to "catch" anything that goes by, then it is a dog pile effect after that.

I have not looked in the new code, It was in my code book back in the 80's as a no no,,
in my opinion, it is bad ju ju


BUT, WAIT!!!! what about a threaded san tee and a dwv adapter for a sink arm? huh huh huh ?????

those are fittings that are designed to be threaded together, not the same thing.
they are tapped at an angle and the threads are shorter ...

 

[cdetorie]

Thank you for your response. As it turns out, I can't easily find a threaded male adapter that would work, so I'll (sigh!) do it the right way and replace the wye. Thanks!