How Does a Garbage Disposal Work? Swapping One Under the Sink

Under a kitchen sink, a SwiftPro tech in a black hoodie, orange gloves and shoe covers unhooks the old disposal and sets it in a blue parts bin on a drop cloth. The new unit is still in its box on the floor beside the tools.

The text on screen walks through what happens when you flip the switch: the motor spins the grinding parts, food breaks into small particles, and water carries them into the drain.

What you can't see from above is the turntable at the bottom of the hopper, the round chamber under your sink opening. It spins fast, and centrifugal force does the rest.