Apr 01, 2019

If your garbage disposal breaks down or you’re updating your kitchen, you might want to know how to replace a garbage disposal. This project is easy enough that an amateur DIYer should be able to handle it – but Newcomb and Company is just a phone call away if you need us!

Should I Replace My Garbage Disposal?

Garbage disposals have a hard time with hard, stringy foods like celery, coffee grounds, and egg shells. Trash can also wreak havoc on your garbage disposal. If your garbage disposal jams, first reach in there and see if you can get out whatever is blocking the unit. If that doesn’t work, unplug the disposal and use an Allen wrench to crank the motor back and forth. You can do this by inserting the wrench into the shaft in the bottom of the unit. If the motor begins to spin freely, run lots of water through the unit and test it to make sure it’s fixed.

How to Remove a Garbage Disposal

If you’ve tried using the Allen wrench, or if you’ve pressed the reset button and your unit is still malfunctioning, it’s time to learn how to replace a garbage disposal. Here, we’ll show you how to remove the current unit and replace it with a new one.




  1. Turn off the power to the unit. If it drains into your dishwasher, loosen the hose clamp that attaches it to the dishwasher discharge hose, and pull the adapter.
  2. Loosen the slip nut at the T-fitting (the white pipe connected to the disposal) and undo the nut securing the tube to the disposal unit. Remove the tube.
  3. Insert a screwdriver into the edge of the retaining ring and rotate it counterclockwise. The unit should break free.
  4. Turn over the disposal unit and remove the electrical box cover. Pull out the wires and remove the twist connectors. You should also remove the fastening nut, found just inside the unit’s electrical box. Pull the connector and wires from the unit.
  5. If necessary, remove the drain fitting by loosening the three bolts in the retaining ring. Slide it up and use a screwdriver to pry the ring up. Lift the drain, and scrape away any old putty still stuck to the basin.

How to Replace a Garbage Disposal


New garbage disposal

Plumber’s putty


  1. Remove the waste lines from the sink. Take the cover plate off of the disposal, and wire it according to the manual.
  2. Attach the sink’s discharge tube to the body of the new garbage disposal.
  3. Underneath the sink, you’ll find the drain flange, backup ring, and fiber gasket. Run plumber’s putty along the underside of the flange into the drain, as well as around the backup ring and fiber gasket. Mount the ring with screws.
  4. Attach the disposal to the sink via the mounting ring. Tighten the ring until the disposal is firmly in place.
  5. Align the discharge tube with the drain trap and attach it.
  6. Tighten the mounting lug on the dishwasher tube.
  7. Plug in your newly replaced garbage disposal!

There are several additional required steps if you’re installing a new garbage disposal. In many cases, this is best done by a professional. If you’re having trouble replacing your garbage disposal or if you’d like to add the convenience of waste disposal to your kitchen sink, contact Newcomb and Company. We’re happy to help with all of your plumbing needs in the Raleigh and Wilmington areas.

Need help? Call now.