Water backing up in a sink with a garbage disposal might be from a clog in the drain pipe below — or a clog in the disposal unit itself. Tough, sinewy food matter that doesn’t belong in a disposal sometimes gets washed down into the unit. Another frequent cause of garbage disposal clogs is feeding too much dry material into the unit without running sufficient water to flush it past the disposal and down the drain pipe. You shouldn’t pour caustic chemicals into a garbage disposal as damage may result. Before you call the plumber, however, here are some things to try if you suspect a clogged garbage disposal.

If the clog seems to be located in the drain pipe below it — the disposal turns on and runs freely but standing water remains in the sink — plunging the disposal with a common household plunger may work. Make sure there are a few inches of standing water in the sink to make a good seal, turn on the disposal and plunge the drain opening vigorously.

If you turn on the disposal and hear nothing — or you hear only a loud hum but the unit doesn’t turn — the clog is probably inside the inner workings of the unit, and plunging won’t work.

Unclogging Using a Hex Wrench

  • A hex wrench supplied with all disposals can be used to manually rotate the inner mechanism of the unit and possibly clear the obstruction.
  • Lay down beneath the disposal and insert the hex wrench into the socket on the bottom of the unit. Rotate the wrench back and forth rapidly several times to break up the obstructing material.
  • Remove the hex wrench and turn on the disposal. If you hear it running, flush the unit with hot water for a minute or so while it runs to flush the blockage down the drain pipe.
  • If the disposal makes only a humming sound or no sound at all, you’ll need a qualified plumber to dismantle the unit and clear the clog.

For professional service to resolve garbage disposal clogs contact Apollo Home Heating, Cooling, Electric and Plumbing.