Inside a worn garbage disposal: rusty grinding plate and lugs seen from the sink

Garbage disposal install and replacement

A disposal hangs on a sink-flange mount, connects to the trap and, if present, the dishwasher drain. Replacing with the same brand family often allows reuse of the existing mount; otherwise install the new flange. Knock out the dishwasher inlet plug only if a dishwasher will connect.

Cross-checked ~90 min moderateBrands: All

Before you start

Turn off the breaker for the disposal and verify dead before touching the wiring.
Support the unit when removing it: it is heavy and drops suddenly when the mount turns.
Hardwired disposals: follow local code; electrician where required.

Diagnostic steps

Unlock all 6 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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