Hello,
I’m replacing my old style washing machine drain hose (now hanging over the utility sink) with a Standpipe drain system. I understand that the building codes require me to use a 2″ pipe and 2″ solvent P-trap. The only problem is that I still want to keep my sink and the sink’s P-trap is downstream of my new Standpipe p-trap. The sink’s p-trap is the typical 1-1/2″. Is it safe to to transition from 2″ to 1-1/2″?
Thanks,
hrh
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Replies
Talking to my building inspector about that same thing, he said the reason for the larger size was that some washers really eject the water out faster than it could be drained before. If that is the reason for the larger elbow and larger pipe... which is also partly a resevoir.
I think you will need to run two drain lines to your sewer/vent stack. The upper one will be for the sink, and will be 1.5", and the lower one will be 2" for the washer. You can't connect them both to the same horizontal drain pipe (that feeds the sewer), or you might pull the water out of one or the others P trap.
Rebuilding my home in Cypress, CA
Also a CRX fanatic!