How to Repair a Sink Drain Problem with a Dishwasher

While there may be many causes for a dishwasher not draining, simple troubleshooting procedures often resolve the problem. Discover what to do if your dishwasher won't drain and how to maintain your dishwasher draining correctly in the future.

What should you do if your dishwasher refuses to drain?Please turn off the power to the dishwasher before troubleshooting it by removing the fuse or Turning off the circuit breaker in the main power panel of your house.

1. Check for a blockage
Check if nothing obstructs the sump (found towards the back of the dishwasher) or the bottom of the tub. If you discover more than two to three cups of standing water, drain as much as possible in a small container. You can unclog a dishwasher by looking for and removing food particles, paper, and other trash.

It should be noted that some dishwashers leave a tiny quantity of water at the bottom of the tub after completing a cycle. Read your owner's handbook to see whether this is usual.

2. Clean the filter of particles.
The filter may be found at the bottom of the dishwasher. It should be placed around the lower spray arm's base or towards the rear of the tub. Even though most dishwashers have built-in grinders for processing food particles and paper, detritus may still block the filter. Remove any debris you detect.

3. Examine the drain hose
The drain hose is a corrugated construction found just under the sink, between the drain pump and the drain line. If the drain line has any kinks, carefully straighten them out.
To clear obstructions in the drain hose, you may need to remove it from its present position. Remove the clamps that keep the drain hose connected to the disposal. Blow through one end to remove the debris if the hose is clogged.

4. Check the garbage disposal.
Check to see whether the kitchen sink drain is plugged in. Remove the drain stopper (a little plastic insert) from your trash disposal and run it to ensure the dishwasher drain is not blocked. Never put your hands down on the trash disposal—this might result in catastrophic damage.

5. Clean the air gap
The little chrome cylinder on the kitchen sink's rear edge is the air gap. Check whether the water comes from the air gap when running the dishwasher. If this is the case, a clog has formed between the air gap and the waste disposer. Remove the air gap lid and wipe the interior with baking soda and water to clear the obstruction.

6. Make sure that the dishwasher door lock is closed.
Your dishwasher will only drain fully if the door is locked. Close the dishwasher door and complete a cycle to check if it drains. If you're having difficulties locking the door, you may need to replace the latch.

7. Examine the drain valve
A drain valve permits water to drain during the wash cycle by opening the solenoid (an electromagnet used in dishwashers). To test the valve, gently press the valve bracket to ensure it slides easily. Not all dishwashers have a drain valve, but if yours has one and seems stuck in place, you may need to repair the drain valve.

8. Test the motor
Ensure that the dishwasher is connected and receiving electricity before testing the motor. Switch on the dishwasher and listen for a buzzing sound. A hum indicates that the engine is getting electricity but is not rotating. If this is the case, you'll need to replace the motor.

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