Project Guide

How to Install a Garbage Disposal

Wire the Disposal
Wire the disposer - Install Garbage Disposer
  • Remove the cover plate beneath the disposer.
  • Connect the appliance cord if the disposer doesn’t come with one.
  • Most cords and disposers have the same colored wires. Connect white to white, black to black, and the green wire to the disposer’s ground screw.
  • Read the manufacturer’s instructions for wiring if the colors are different.
Apply Plumber's Putty
Apply plumber’s putty - Install Garbage Disposer
  • Press a rope of plumber’s putty onto the underside of the drain flange.
  • Insert the flange into the drain hole and press down evenly.
  • Install the backup ring, fiber gasket and mounting ring from beneath the sink.
Install Mounting Ring
Install mounting ring - Install Garbage Disposer
  • Tighten the mounting screws for the upper mounting ring.
  • Alternate the tightening of the screws to pull the ring up evenly against the sink.
Mount the Disposal
Mount the disposer - Install Garbage Disposer

Place the disposer into the mounting ring.

  • Make sure the outlet of the disposer is facing the drain pipe connection.
  • Turn the lower ring clockwise until the disposer is supported by the mounting assembly.
Connect Outlet to P-Trap
Connect outlet to p-trap - Install Garbage Disposer
  • Use a hacksaw or tubing cutters to measure the discharge pipe and cut it to length.
  • Install the discharge pipe to the outlet of the disposer.
  • Attach to the drain line with slip nuts.
Tighten Mounting Lug
Tighten mounting lug - Install Garbage Disposer
  • Insert a screwdriver or disposer wrench into the mounting lug on the lower mounting ring.
  • Turn clockwise until the disposer is locked into place.
  • Tighten all slip nuts snug using water-pump pliers.
  • Run water into the sink.
  • Turn on the disposer and check for leaks.
  • Tighten fittings if necessary.

Consider the following when shopping for new appliances:Consider the following when shopping for new appliances:

  • 3-prong plugs are used for homes build before the year 2000. 
  • 4-prong plugs are used for homes built after the year 2000. 

When you add professional installation to your new appliance purchase from The Home Depot, a compatible cord is required. The delivery agent carries both types of cords to make sure your home is covered.

When you purchase a new appliance from The Home Depot without professional installation, a 4-prong cord is sent by default. If your home is equipped with a 3-prong outlet, you will need to purchase a 3-prong cord or connector adapter separately.