Newly installed Electrolux disposal runs, but water and food back up into the sink or dishwasher immediately.

Safety First: Turn OFF power at the breaker and disconnect the dishwasher drain hose before working on the disposal inlet.

• Step 1 – Check dishwasher inlet: Remove the dishwasher drain hose from the disposal inlet nipple. Shine a flashlight into the inlet. If you see a solid plastic wall, the knockout plug is still installed.
• Step 2 – Remove the knockout plug: Insert a screwdriver into the inlet and tap gently with a hammer to knock out the plug into the grinding chamber. Retrieve the plastic disk from inside the chamber with tongs.
• Step 3 – Inspect the discharge elbow and gasket: Confirm the discharge elbow is oriented correctly and the rubber discharge gasket is not twisted or blocking the outlet.
• Step 4 – Reconnect dishwasher hose: Reattach the dishwasher drain hose with a proper clamp. Ensure there is a high loop in the hose to prevent backflow.
• Step 5 – Test operation: Restore power, run water, and operate the disposal. Then run the dishwasher briefly to confirm proper draining.