Sink won’t drain

Start with where the water stops, because that tells you where the clog is.

• One bathroom sink is slow: hair on the stopper. Pull it and clean it, then plunge.
• One kitchen sink, with a disposal: run the disposal first. If it hums or won’t turn on, it’s jammed, not clogged. See garbage disposal humming or not working.
• Water sits in the trap: clean the P-trap with a bucket underneath.
• Both sides of a double sink back up: the clog is past the trap. Snake the line in the wall.
• Several drains back up at once: the main line. That’s a plumber.

Our guide plunger, snake or drain cleaner puts these in order and explains why caustic cleaners come last. The videos are on Unclog a drain and Fix a garbage disposal.