I want to put a utility sink in the basement with a tank and pump to discharge overhead. Almost exactly above the sink location in the basement is our washing machine upstairs. It discharges through a rubber hose with a 180 degree bend in the end, which goes into a PVC pipe that extends upward about 4’ from the floor (conveniently, it’s not buried in the wall).
I hope I can replace part of this pipe with a larger diameter into which I can put both the existing washing machine drain and a new pipe from the sink downstairs. Certainly, this is physically possible, there’s room for a larger pipe and easy access for cutting.
Just wondering if there is anything weird that could go wrong. For example, if the present pipe (I think it’s 1.5" nominal) is big enough for the washer, would 3" pipe with a reducer to 1.5" be OK? Or would the reducer be enough of an obstruction to threaten overflows?
Thanks!