Dishwasher: Not Draining

Opening your dishwasher to find an inch of murky water sitting in the bottom of the tub is unpleasant, but it is a problem that has a defined set of causes. Working through them methodically will usually identify and resolve the issue without professional help.

Start with the filter and the drain area at the bottom of the tub. Remove the lower rack and unscrew the filter assembly. Rinse it under running water and use a soft brush to scrub away any accumulated grease, food particles, or soap residue. While the filter is out, look into the sump area for any debris — broken glass, pit seeds, or plastic fragments are common causes of drain pump blockages.

The drain hose runs from the pump to either your sink drain or a dedicated air gap fitting on the countertop. A kinked hose or a clog inside it will prevent water from leaving the tub. Disconnect the hose at both ends and blow through it — any resistance indicates a blockage. Also ensure the hose forms a high loop up near the underside of the countertop before it connects to the drain; without this loop, water from the sink drain can back-siphon into the dishwasher.

If the filter and hose are clear, the drain pump is the next component to test. You should hear the pump activate near the end of each cycle. A pump that hums but does not move water has a jammed impeller; a completely silent pump has failed electrically. Both conditions require pump replacement.