How to Install a Bathroom Vanity Drain
- 1). Turn off the water supply to prevent accidents while you're working. The water supply knobs are usually located beneath the sink. There are two valves. One for hot and one for cold. Rotate the knobs clockwise to shut them off.
- 2). Clean out the bottom of the sink, paying particular attention to where the drain hole is. Use a standard bathroom cleaner and rags. Remove any traces of old caulk or putty from around the vanity drain hole.
- 3). Turn the drain flange over so the bottom is pointing up. Place a thin line of plumber's putty around the edge of the rim. Turn the flange back over right side up. Press this into the drain hole in the vanity, twisting as you do so to spread the caulk.
- 4). Position yourself underneath the sink. Connect the tail piece to the underside of the drain flange by twisting it into place. Thread the rubber washer and jamb nut over the end of the tail piece and push these into place so they are flush with the bottom of the sink. Tighten the jamb nut with the pliers.
- 5). Wrap the threads on the tail piece and the sewer inlet pipe with plumber's tape.
- 6). Insert the P-trap in place between the tail piece and the sewer inlet. Tighten the couplings with the pliers.
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