How to Replace a Garbage Disposal

A failing disposal hums, leaks, or smells permanently. Replacement is a 90-minute job once you know the trick for fitting the mounting ring.

Shut off power at the breaker — disposals are usually on their own switch but verify with a voltage tester before disconnecting anything. Unplug or disconnect the wiring depending on your model.

From below, disconnect the discharge tube and dishwasher hose. Twist the old disposal off its mounting ring (counter-clockwise from below). Most disposals weigh 10–15 lb, so brace it with a knee or a paint can while you work the connection loose.

Mounting rings between brands are often compatible (InSinkErator's EZ Mount is on most newer units). If you're replacing same-brand, you can usually skip the sink-flange step entirely — just twist the new unit onto the existing ring. If switching brands, remove the old flange, scrape the old plumber's putty, roll a fresh rope of putty, install the new flange and mounting hardware per the manual.

Wire the new unit, hang it on the ring, twist to lock, and reconnect drain and dishwasher hose. Critical step: insert the knockout plug remover hammer-tap if you're connecting a dishwasher — new disposals ship with the dishwasher inlet plugged, and a forgotten knockout will back the dishwasher up into itself.