A slow draining sink is a sign of a clogged P-trap
A slow draining or blocked bathroom sink invariably is caused by a clogged P-trap. This U-shaped pipe under the sink is designed to prevent sewer gasses from backing up into the bathroom. A plunger sometimes can be used to clear blockages. Some P-traps are fitted with a drain plug at its lowest point that can be removed, allowing you to fish out debris with a bent wire coat hanger. If all else fails you can either call a plumber or you can save some money by replacing the P-trap yourself.
Instructions
1. Place a bucket under the sink to catch the water trapped in the pipe. Unscrew the connecting nuts on both ends of the P-trap. If it's made of white PVC, you'll be able to loosen the nuts by turning them counterclockwise by hand. If the fitting is made of chrome-plated metal, use a pair of channel lock pliers. Adjust the pliers to the correct width and wrap a rag around the nut to prevent the jaws from damaging the plating. Grip with the pliers and turn the nut counterclockwise to break the seal, and then remove the nut by hand.
2. Twist the P-trap away from the sink drain and slide it out of the wall socket. Stuff an old rag into the outlet pipe to prevent odors the bathroom. Use the old P-trap as a sample and purchase the same size white ABS plastic P-trap replacement, together with a sink transition piece and slip joint extension if necessary. Get a kit containing all the replacement nuts and gaskets you'll need and a tube of plumber's thread compound.
3. Remove the rag plug and test fit the tailpiece into the wall pipe. If the tailpiece is too long, the up pipe may not line up with the sink drain pipe. If this is the case, measure the difference with a ruler and mark the amount to be removed from the new P-trap with a pencil. Use a plastic pipe saw to cut the wall tailpiece to the correct size.
4. Assemble the P-trap. If a transition piece and/or slip joint extension is needed, smear a small amount of threading compound onto the threads and thread the P-trap up pipe nut onto the transition piece and/or the outlet pipe onto the transition piece. Tighten the connecting nuts snugly without exerting force. Place the final connecting nuts onto both ends of the P-trap and slip the round gaskets into place.
5. Put a small amount of plumber's thread compound on the threads of the sink drain pipe and the threads on the wall pipe. Insert the P-trap exit end into the wall pipe and thread the connecting nut on without tightening. Attach the up pipe the same way. Tighten both by hand, but don't exert force and tighten them too much. Doing so will distort the gaskets and cause leaks.
6. Put the plug in the sink and fill it with water. Remove the plug and let the sink drain. Inspect the joints for leaks. If you have an obvious leak, loosen the connecting nut half a turn. Plug the sink, fill with water and drain. Tighten the connecting nut gradually until the leak stops. Wipe the pipes dry and wrap some toilet paper around all the joints and secure the ends with a bit of cellophane tape. Refill and drain the sink. Leave for ten minutes before unwrapping the toilet paper. If all the pieces are completely dry, you have watertight seals on all connecting nuts.
Tags: connecting nuts, , , wall pipe, backing into