I recently bought house in Frot Lauderdale that is 45yrs old and has a laundry drywell. My question is that the pvc pipe is capped on the end with some kind of valve and want to know if i can just "cut" the top off the pvc and insert the washer drain hose??? is this an anti-back flow valve? and do i really need it or does this vavle prevent any oders?..i just cant decide on what to do....thanks