Older laundry tubs drain the washing machine leaving dirt and soap scum stains.
Discharging the rinse water into a standpipe keeps the tub clean. Using an air admittance valve ensures the tub will drain smoothly and gives you a clean-out. And the hanging unit allows for adjusting the height higher or lower, and removes the legs being on the floor.

Some points and tips:
- the standpipe should be 30 – 36 inches to prevent water overflow
- deburr cut PVC pipe as lint and material will catch to create blockages
- glued PVC needs a twist to assure a good connection
- use a carbide bit for masonry walls
- it is best and easier to drill a smaller hole first, then drill the correct size hole
- put the tub’s trap on before the lower plumbing for correct measurements
- after connections are hand-tightened, run hot to check for leaks, then tighten again
- the air admittance valve prevents air lock, and sewer gas odor
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