Quick answer
If your dishwasher water isn't draining completely, first check the drain hose for clogs and clear any debris. If the issue persists, inspect the drain pump and filter for blockages or damage.
Confirm the symptom
- Standing water in the dishwasher after a cycle
- Dishes are still wet or soapy after the cycle ends
- Unpleasant odor from the dishwasher due to stagnant water
- Dishwasher error code related to drainage issues
Tools and prep
- Screwdriver set
- Plunger or wet/dry vacuum
- Bucket
- Flashlight
- Rubber gloves
- Plumber's snake or wire hanger
- Turn off power to the dishwasher at the circuit breaker
- Shut off the water supply to the dishwasher
Step-by-step troubleshooting
- Check for Standing WaterDo: Open the dishwasher door and look for water remaining in the bottom of the unit.Observe: Water pooled at the bottom indicates a drainage issue.Means: There is a blockage or malfunction in the drainage system.Next: Check the drain hose for clogs.
- Inspect the Drain HoseDo: Locate the drain hose and check for kinks, clogs, or debris.Observe: Clogs or kinks in the hose prevent water from draining properly.Means: The drain hose is partially or fully blocked.Next: Clear the clog or straighten the hose.
- Clear the Drain Hose ClogDo: Use a plumber's snake or a straightened wire hanger to remove debris from the hose.Observe: Debris or food particles come out of the hose.Means: The clog was successfully removed.Next: Run a test cycle to see if the issue is resolved.
- Check the Air Gap (if applicable)Do: Inspect the air gap on the countertop for blockages.Observe: Debris or standing water in the air gap.Means: The air gap is clogged and needs cleaning.Next: Clean the air gap thoroughly.
- Clean the Dishwasher FilterDo: Remove and clean the dishwasher filter under the spray arm.Observe: The filter is clogged with food particles and debris.Means: A dirty filter restricts water flow.Next: Rinse the filter and reinstall it.
- Inspect the Drain PumpDo: Locate the drain pump and check for clogs or damage.Observe: Debris in the pump or damaged impeller.Means: The drain pump is clogged or faulty.Next: Clean the pump or replace it if damaged.
- Test the Drain Pump MotorDo: Use a multimeter to test the drain pump motor for continuity.Observe: No continuity indicates a faulty motor.Means: The drain pump motor needs replacement.Next: Replace the drain pump motor.
- Check the Drain Line ConnectionDo: Ensure the drain line is properly connected to the sink or garbage disposal.Observe: Loose or disconnected drain line.Means: Improper connection prevents proper drainage.Next: Secure the drain line connection.
- Run a Test CycleDo: Start a short cycle to see if the water drains completely.Observe: Water drains without issues.Means: The problem is resolved.Next: Monitor the dishwasher for recurring issues.
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Clogged Drain Hose Food particles, grease, or debris can block the hose. | Common | Easy | None |
| Clogged Air Gap The air gap prevents backflow but can become clogged with debris. | Sometimes | Easy | None |
| Clogged Dishwasher Filter A dirty filter restricts water flow and causes drainage issues. | Common | Easy | None |
| Faulty Drain Pump A damaged or clogged drain pump cannot pump water out. | Sometimes | Medium | Drain Pump |
| Clogged Garbage Disposal or Sink Drain If the dishwasher drains into a disposal or sink, a clog there can cause backup. | Sometimes | Easy–Medium | None |
| Faulty Drain Pump Motor A failed motor prevents the pump from operating. | Rare | Medium | Drain Pump Motor |
| Improper Drain Line Installation A kinked or improperly sloped drain line can trap water. | Rare | Medium | Drain Line |
| Blocked Drain Valve A stuck or clogged drain valve prevents water from exiting. | Rare | Medium | Drain Valve |
| Malfunctioning Float Switch A faulty float switch can prevent the pump from activating. | Rare | Hard | Float Switch |
| Incorrect Water Temperature Cold water can cause grease to solidify and clog the drain line. | Rare | Easy | None |
Parts matching
If your dishwasher water isn't draining completely, you may need to replace certain parts. Here are the most common parts associated with this issue:
- Drain Pump
- Drain Pump Motor
- Dishwasher Filter
- Drain Hose
- Drain Valve
- Float Switch
Before purchasing any parts, ensure they are compatible with your dishwasher model by checking the owner's manual or the manufacturer's website.
When to call a professional
- Water continues to pool after clearing all clogs and cleaning components
- Drain pump makes loud noises or fails to operate
- You suspect a major electrical issue with the pump motor
- Standing water causes a foul odor or mold growth
- The dishwasher displays a persistent error code related to drainage
- You are unsure about electrical testing or part replacement
FAQ
How often should I clean my dishwasher filter?
It is recommended to clean the dishwasher filter every 1–2 months to prevent clogs and maintain proper drainage.
Can I use a drain cleaner on my dishwasher drain hose?
Avoid using chemical drain cleaners as they can damage the hose and internal components. Instead, use a plumber's snake or a straightened wire hanger to clear clogs.
Why is my dishwasher draining slowly even after cleaning the filter and hose?
A slow drain after cleaning may indicate a clogged garbage disposal, a faulty drain pump, or a blockage in the drain line connection.
What should I do if the drain pump motor is not working?
If the drain pump motor is not working, it will need to be replaced. Turn off the power to the dishwasher before attempting any repairs.
Can a clogged air gap cause drainage issues?
Yes, a clogged air gap can prevent water from draining properly. Clean the air gap regularly to avoid this issue.