If your dishwasher is leaving standing water at the bottom after every cycle, draining slowly, or making a strange humming sound during the drain phase, there is a very good chance the drain pump filter is clogged. Good news: this is the single easiest dishwasher fix you can do yourself. It requires no tools, no parts, no experience, and takes about 15 minutes. And it solves a repair problem that would cost 150 to 250 dollars from a professional service call.
This guide walks through exactly what a drain pump filter does, how to find yours, how to safely remove and clean it, warning signs that mean the problem is beyond simple filter cleaning, and how to prevent future clogs.
What the Drain Pump Filter Does
Modern dishwashers have a small mesh or cylinder filter at the bottom of the tub that catches food debris, glass shards, plastic pieces, and other solids before they reach the drain pump. This prevents small objects from damaging the pump impeller and clogging the drain line.
The problem is that this filter needs regular cleaning. Most manufacturers recommend cleaning every 1 to 3 months depending on how heavily you use the dishwasher. Most homeowners never touch it. After 6 months to a year, the filter clogs up enough that water cannot flow through fast enough to drain properly.
When this happens, you see standing water in the bottom of the tub after cycles complete. The dishwasher may also start throwing error codes or leaving dishes dirtier than usual because the wash water is not circulating cleanly.
Signs Your Filter Is Clogged
Any of these mean your drain pump filter needs cleaning immediately:
Standing water in the bottom of the tub after every cycle.
Dishes come out with debris or gritty residue on them.
Dishwasher smells bad, especially between cycles.
Drain phase of the cycle takes noticeably longer than usual.
You hear a straining or humming sound during drain phase.
Error codes appear on the display indicating drain issues (varies by brand).
Dishes come out not fully clean even though soap and rinse aid are stocked.
These symptoms almost always trace to the drain filter. In fact, before calling for any dishwasher service, cleaning this filter should be your first step. It resolves about 40 percent of dishwasher drain complaints entirely.
Tools You Need
Nothing special. Just have these ready:
Old towel or shop rag.
Soft brush (an old toothbrush works perfectly).
Warm soapy water in a small bowl.
Flashlight (phone flashlight is fine).
Bowl or container to hold the filter parts.
Optional: rubber gloves if you dislike touching food debris.
That is the entire tools list. No screwdrivers, no wrenches, no special equipment.
Step by Step Filter Cleaning Instructions
Step 1: Turn off power to the dishwasher. Either unplug the unit under the sink or flip the breaker labeled kitchen or dishwasher. This is optional for filter cleaning but good practice.
Step 2: Open the dishwasher and remove the lower rack. Slide it fully out and set it aside. This gives you clear access to the bottom of the tub.
Step 3: Locate the filter assembly. Look at the bottom of the tub, usually near the back center under the lower spray arm. You will see a cylindrical or dome shaped part that looks like a mesh strainer. Depending on your model, there may be one piece or two nested pieces.
Step 4: Remove the upper filter. Most models have a top filter that twists counterclockwise to unlock. Turn it about a quarter turn until you feel it release, then lift straight up. If it does not twist, check your dishwasher manual (available online by searching your model number plus manual). Some models have a locking tab that must be pressed first.
Step 5: Remove the lower filter (if present). Some dishwashers have a second larger mesh filter underneath. This usually lifts straight up without twisting. Set both filter parts in your bowl.
Step 6: Clean the filter parts. Rinse under running warm water. Use the soft brush to gently scrub away any stuck food debris, grease film, or mineral buildup. Do not use metal wire brushes or sharp tools. These can damage the fine mesh.
Step 7: Inspect the filter housing area. Now look down at the empty filter housing in the bottom of the tub. Use the flashlight to check for any food debris, broken glass, or objects that have accumulated below where the filter sits. Use a paper towel to wipe out anything you find.
Step 8: Check the drain outlet. Underneath where the filter goes, you should see the drain opening. Verify it is clear of debris. If you can see down into it, look for any obstructions.
Step 9: Reinstall the filter parts. Put the lower filter back in first (if applicable). Then place the upper filter and twist clockwise to lock it in place. Make sure it clicks or feels seated firmly. A loose filter will not work properly.
Step 10: Replace the lower rack and close the door. Restore power if you turned it off. Run a short cycle (usually a rinse only or shortest wash) to verify drainage works correctly.
What to Do If Cleaning Does Not Solve It
If you cleaned the filter thoroughly and the dishwasher still does not drain properly, the problem is deeper. Possible causes:
Clogged drain hose. Behind the dishwasher, the drain hose connects to your garbage disposal or air gap. Food debris can accumulate here. Disconnecting and clearing requires some plumbing knowledge.
Garbage disposal knockout plug still in place. If your dishwasher connects to a newly installed garbage disposal, there is a small plastic plug inside the disposal that must be knocked out. If it is still there, no water can drain from the dishwasher.
Clogged air gap. If you have an air gap fitting on your sink counter, food debris can clog it. Remove the top cap and clean any buildup.
Failed drain pump. If all drain path items are clear and the dishwasher still will not drain, the drain pump itself has failed. This is a professional repair, typically 175 to 300 dollars.
If you have cleared the filter and the problem persists, book professional service. Our team at dishwasher repair Des Moines service handles drain pump replacement, drain hose diagnostics, and full dishwasher diagnostics with parts on the truck.
How Often to Clean the Filter
Frequency depends on your usage patterns:
Heavy use (daily runs with dinner plates loaded with sauces and food residue): Every 4 to 6 weeks.
Moderate use (3 to 5 times per week with reasonable pre rinse): Every 2 to 3 months.
Light use (2 to 3 times per week with thorough pre rinse): Every 3 to 6 months.
Very light use (1 to 2 times per week, mostly rinsed dishes): Every 6 months.
Regardless of usage, if you see any warning signs mentioned earlier, clean immediately. Regular cleaning prevents the small clog from becoming a serious drain problem or a mold and odor issue.
What Not to Put in the Dishwasher
Prevention is easier than cleaning. Keep these out of your dishwasher to reduce filter clogging:
Whole pieces of food larger than a quarter inch. Scrape plates before loading.
Fruit stickers. These peel off in the wash and clog the filter and drain.
Toothpicks or small skewers. These slip through the filter mesh and can damage the pump impeller.
Broken glass. If a glass breaks in the dishwasher, remove all pieces before running any more cycles.
Chicken bones, fish bones, or shellfish shells. Too solid for the filter to handle. Also creates bacterial growth.
Rice, pasta, or noodles. Small enough to slip through pre rinse but they accumulate and clog fast.
Sticker residue or duct tape residue on containers. Gums up the filter mesh.
Brand Specific Notes
Bosch dishwashers: Bosch has one of the easiest filter removal designs. Twist and lift, no tools required. Their filter is designed for less frequent cleaning (every 2 to 3 months) due to superior wash quality.
Whirlpool and KitchenAid: Similar twist and lift filter design. May have a lower filter that lifts straight up under the twist off upper filter.
LG dishwashers: Filter usually cylindrical shape that twists counterclockwise to unlock. Some models have finer mesh that clogs faster than average.
Samsung dishwashers: Similar to LG. Some models have a filter cleaning reminder built into the control panel.
Frigidaire and GE: Filter design varies by year and model. Check the manual for your specific unit.
Older dishwashers (pre 2010): Some older units have a hard food disposer instead of a user cleanable filter. These typically do not require cleaning but can still develop drain issues from broken parts.
When DIY Filter Cleaning Is Not Enough
Book professional service same day if:
Filter looks clean but standing water persists after cycles.
Water is actively leaking underneath the dishwasher.
You see broken parts inside the filter housing or drain area.
The unit throws error codes even after filter cleaning.
Drain phase of cycle stops working entirely (no water pumps out).
You hear grinding or unusual noises during the drain cycle.
Any of these signals a deeper issue that filter cleaning cannot solve. If you need appliance repair near me in the Des Moines metro to handle a dishwasher issue beyond simple filter cleaning, our team offers same day service with parts on the truck for most common failures.
Related Dishwasher Maintenance
While you have the filter out, do these additional maintenance items for maximum dishwasher longevity.
Wipe the door seal with warm soapy water. Mold and mineral buildup here causes bad odors and eventually seal failure.
Clean the spray arms. Remove them (usually twist off) and check the small holes for mineral or debris clogs. Soak in warm vinegar for 30 minutes if clogged.
Wipe the interior with a damp cloth. Remove any visible food residue on walls or racks.
Refill the rinse aid dispenser. Empty rinse aid causes spotting and film issues that mimic bigger problems.
Check the water inlet screen. Some models have a small screen behind where the water inlet hose connects. Cleaning it can improve fill performance.
Water Quality Considerations for Central Iowa
Des Moines area water at 8 to 15 grains per gallon deposits mineral scale on dishwasher components over time. This affects filter cleaning frequency and cleaning effectiveness.
If your area has particularly hard water, consider a whole home water softener. Softened water dramatically reduces filter buildup and extends dishwasher lifespan.
Add a dishwasher cleaner (Affresh or similar) every 2 to 3 months to descale interior components including the pump and hoses. This complements filter cleaning.
Use rinse aid in every cycle. This prevents mineral spotting and helps flush residue through the filter faster.
West Metro Considerations
Newer construction homes in west metro Des Moines often have premium dishwashers (Bosch, KitchenAid, Miele) with sophisticated filter systems that require less frequent cleaning but benefit from careful maintenance. If your premium dishwasher has developed drain issues that filter cleaning did not resolve, our appliance repair West Des Moines service includes certified premium brand technicians with OEM parts for common repairs.
Frequently Asked Questions
Can I clean the filter with bleach?
No. Bleach can damage the filter mesh and rubber seals. Use warm soapy water with a soft brush only.
How do I know if I have a self cleaning dishwasher without a user cleanable filter?
Look at the bottom of the tub. If there is no obvious filter to twist or lift, you probably have an older hard food disposer style unit. Check the manual for your specific model.
My filter looks fine but water still stands. What now?
Check the drain hose behind the dishwasher, the garbage disposal knockout plug if newly installed, and the air gap on the counter if present. If all are clear, the drain pump has likely failed.
Should I run the dishwasher empty after cleaning the filter?
Yes. Run a short rinse cycle to verify the drain works properly and to flush any small debris left after cleaning.
Can I use vinegar to clean the filter?
Yes. Soaking the filter in 50/50 warm water and white vinegar for 30 minutes removes mineral scale and improves flow.
Book Professional Service If Needed
Filter cleaning solves most dishwasher drain issues but not all. If you have cleaned the filter, checked the drain path, and your dishwasher still refuses to drain properly, book professional service. Do not run additional cycles hoping the problem resolves. Water sitting in the tub creates bacterial and odor problems fast. Our full appliance repair Des Moines team handles dishwasher drain pump replacement, drain hose diagnostics, and full system service with same day availability across the metro. Call (319) 410-0530 to book.
A well maintained dishwasher lasts 12 to 15 years or more. Regular filter cleaning is the single most important thing you can do to extend that lifespan and avoid expensive repairs.
Sources: Whirlpool official dishwasher maintenance and troubleshooting resources, ENERGY STAR dishwasher efficiency and maintenance guidance, and the CDC guidance on water quality and household appliance maintenance.