🔧 Repair or Replace
Dishwasher Not Draining? Five Checks Before You Call a Technician
Standing water in the bottom of a dishwasher usually has a cheap cause you can fix yourself in under an hour.
Marcus Ibe · Sep 27, 2026 · 4 min read · 6 steps
A pool of murky water left after a cycle is one of the most common appliance complaints. Before booking a repair visit, it is worth working through the simple causes, which account for most cases.
Switch the dishwasher off at the wall or breaker first, and keep towels handy: there will be water.
1. Clean the filter
Most modern dishwashers have a removable filter under the lower spray arm. Twist it out, rinse it under the tap, and scrub the mesh with a soft brush. A clogged filter is the single most common reason for poor draining.
2. Check the drain hose
The flexible hose running from the dishwasher to the sink drain or waste disposal can kink, especially if the machine was recently pushed back into its space. Check it along its length. Many installations also need a high loop or air gap to stop dirty sink water flowing back in.
3. Clear the sink connection
If the hose joins a waste disposal unit, run the disposal for a few seconds: food in the disposal can block the dishwasher outlet. If the disposal was newly installed, check that the knockout plug inside the dishwasher inlet was removed.
4. Inspect the drain pump
Under the filter there is usually a small cover over the drain pump. With the power off, remove it and check for broken glass, fruit stones, or labels that can jam the impeller.
5. Run a cleaning cycle
Grease and detergent residue build up in the sump. Run an empty hot cycle with a dishwasher cleaner, or a cup of white vinegar on the top rack.
When to call for help
- The pump hums but does not move water after clearing debris
- You hear grinding noises from the pump
- An error code points to the drain pump or control board
- The machine is more than ten years old and the repair quote is high
This is general home-maintenance information, not professional advice. Building codes, permits, and safe practices vary by location — consult a licensed contractor, electrician, or plumber for work beyond your experience.