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

Dishwasher won't drain or drains into the sink after a new disposal install

New disposals ship with a plastic knockout plug sealing the dishwasher inlet. If the dishwasher hose was connected without knocking it out, the dishwasher cannot drain. Knock the plug out and remove it from the chamber; also check the hose loop or air gap and the 7/8 in inlet connection.

Cross-checked ~30 min easyBrands: All

Before you start

Turn off the disposal's breaker and unplug before removing the unit
Support the unit when removing it from the mount
Never reach into the chamber with power connected

Diagnostic steps

Unlock all 5 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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