Disposal runs but water backs up into sink and does not drain through the unit

Safety first: Turn off the disposal and shut off the breaker. Do not use chemical drain cleaners in or before the disposal.

• Check for simple blockage: Run water and briefly turn on the disposal. If the chamber empties slowly or not at all, proceed to plumbing checks.
• Remove and clean the P-trap: Place a bucket under the trap. Loosen the slip nuts and remove the P-trap and discharge elbow from the disposal. Clear any food sludge or obstructions.
• Inspect the disposal discharge port: Use a small brush or bottle brush to clean the outlet on the side of the InSinkErator housing.
• Check downstream drain: If the trap is clear, the blockage may be further in the wall. Use a drain snake from the trap arm into the branch line.
• Reassemble and test: Reinstall the trap and elbow, tighten slip nuts, run water, and test the disposal for proper draining.