Garbage disposal runs but water backs up into the sink and does not drain

Safety First: Turn OFF the disposal and do not run it while the sink is backed up.

• Check the discharge elbow: Place a bucket under the disposal discharge. Loosen the slip nut and remove the discharge elbow. Clear any food buildup or obstructions.
• Inspect the P-trap: Remove the P-trap and horizontal drain arm. Clean out any sludge, grease, or food debris. Reassemble with the washers correctly oriented.
• Dishwasher knockout plug: If a dishwasher is connected, disconnect the hose from the Waste Maid dishwasher inlet and verify the internal knockout plug has been removed. If still present, carefully knock it out with a screwdriver and hammer (unit removed or fully supported).
• Flush the line: After reassembly, run hot water and test the disposal. If the sink still backs up, the blockage may be further down the wall drain and may require a drain snake or plumber.