At a glance
Symptoms
- • Gritty, sandy, or cloudy residue left on glasses and plates after a cycle.
- • Standing water pooling in the bottom of the tub at the end of the wash.
- • Foul, swampy, or sour odors emanating from the dishwasher when you open the door.
- • Noticeable decrease in overall cleaning performance and water pressure.
- • Gurgling sounds during the drain cycle.
- • Visible food particles or grease sludge around the bottom spray arm.
Common causes
- • Prevents old food particles from recirculating and baking onto your freshly washed dishes.
- • Protects the delicate drain pump impeller from catastrophic damage caused by hard debris like popcorn kernels, fruit pits, or broken glass.
- • Reduces calcium and limescale buildup, which is especially critical in Southern California's notoriously hard water (250-400 ppm).
- • Eliminates breeding grounds for mold, mildew, and odor-causing bacteria in the warm, damp tub.
- • Extends the overall lifespan of the dishwasher's wash motor and circulation system by reducing strain on the pumps.
Safety First — Read Before You Start
- •Always wait for the dishwasher to cool down completely before reaching inside, as the exposed heating element at the bottom of the tub can cause severe burns.
- •Watch out for hidden sharp objects like broken glass, toothpicks, or bone fragments trapped in the filter mesh or sump pit.
- •Never operate the dishwasher with the filter removed; doing so will allow debris straight into the wash pump and can permanently destroy the appliance.
- •Avoid using wire brushes, steel wool, or harsh abrasive pads, which will tear the delicate fine-mesh filter screen and require a costly replacement.
Tools & supplies you'll need
- Soft-bristle brush (an old toothbrush works perfectly)
- Mild degreasing dish soap (e.g., Dawn)
- Distilled white vinegar (approx. $3-$5 per gallon)
- Sponge or microfiber cloth
- Shop vac or turkey baster (optional, for removing standing water)
- Flashlight (to see into the dark sump area)
Step-by-step instructions
Prepare the Dishwasher and Clear the Area
Start by ensuring the dishwasher has completed its cycle and the interior is fully cooled down. Open the door fully and pull the bottom dish rack all the way out. To give yourself unobstructed access to the tub floor, lift the bottom rack completely off its tracks and set it aside on your kitchen floor. Grab a flashlight and inspect the bottom of the tub. If there is a deep pool of standing water covering the filter area, use a sponge, a turkey baster, or a wet/dry shop vac to remove the excess water so you can clearly see the filter assembly.
Tip: Keep a small towel handy to kneel on, as reaching into the back of a dishwasher can be hard on your knees, especially if it's installed under a standard 34-inch counter.
⚠Warning: Do not touch the dark metallic heating element ring at the bottom of the tub if the dishwasher was recently run—it retains heat for a long time.
Locate and Unlock the Filter Assembly
Look at the lowest point of the dishwasher tub floor, usually directly beneath the lower spray arm. You will see a circular plastic piece, often resembling a small inverted cup or cylinder. This is the coarse filter. Most modern dishwashers use a simple twist-and-lock mechanism. Grasp the top of the cylindrical filter and twist it counter-clockwise (about a quarter turn). You should feel it unlock and release from the base. Some models may have directional arrows molded into the plastic indicating the 'Lock' and 'Unlock' directions.
Tip: If the filter is stuck and won't turn, do not force it with pliers. Wiggle it gently back and forth while running a little hot water over it to loosen any hardened grease or scale.
Remove the Coarse and Fine Filters
Once unlocked, pull the cylindrical coarse filter straight up and out of the dishwasher. Beneath or surrounding this cylinder, you will typically find a larger, flat, crescent-shaped piece of metal or plastic with a very fine mesh screen—this is the fine filter. Lift this flat filter plate out as well. Carry both pieces to your kitchen sink. Take a moment to inspect the mesh on both filters for any tears, holes, or warping. If the mesh is compromised, it can no longer protect your pump, and you will need to order a replacement part.
âš Warning: Handle the flat fine-mesh filter by its plastic edges. The metal mesh is delicate and can easily crease or puncture if pressed too hard.
Scrub the Filters Under Warm Running Water
Run warm water in your sink. Apply a few drops of a high-quality degreasing dish soap to your soft-bristle brush or old toothbrush. Gently scrub the inside and outside of the cylindrical coarse filter to dislodge trapped food particles, grease paste, and coffee grounds. Next, carefully scrub the flat fine filter. Pay special attention to the microscopic holes in the mesh; grease tends to film over these holes, completely blocking water flow. Rinse both pieces thoroughly until the water runs clear and completely passes through the mesh without pooling.
Tip: For stubborn, greasy sludge that won't scrub off, plug the sink and let the filters soak in hot, soapy water for 10 minutes before brushing.
Tackle Hard Water Scale (The California Special)
If you live in an area with hard water—like Los Angeles, Orange County, or San Diego—you will likely notice a chalky, white, or yellowish crust on the plastic framework or clouding up the fine mesh. This is calcium carbonate scale. Dish soap will not remove this. Fill a bowl with warm distilled white vinegar and submerge the filter components for 20 to 30 minutes. The acetic acid in the vinegar will safely dissolve the hard water minerals. After soaking, give them a final gentle scrub and rinse.
âš Warning: Never use bleach to clean your dishwasher filters. Bleach can degrade the plastic components and, if mixed with vinegar or other cleaners, creates toxic fumes.
Clean Out the Sump Pit
Before reinstalling the clean filters, take your flashlight and look down into the hole (the sump) where the filters sit. This area leads directly to the drain pump and circulation motor. Use a damp cloth or sponge to wipe away any greasy sludge lining the walls of the sump. Carefully reach in with your fingers to feel for heavy debris that might have bypassed the filter, such as unpopped popcorn kernels, fruit pits, or shards of broken glass. Removing these now prevents a jammed impeller later.
Tip: If you find broken glass in the sump, use a pair of needle-nose pliers or a slice of soft bread pressed against the glass to safely pick up the shards without cutting your fingers.
Reassemble and Lock Securely
Place the flat fine filter back into the bottom of the tub, ensuring it sits perfectly flush against the floor without any gaps. Next, insert the cylindrical coarse filter back into its central hole. Press down slightly and twist it clockwise until you feel it click or lock firmly into place. If there are alignment arrows, make sure they match up. It is absolutely critical that the filter is locked tightly; if it vibrates loose during a wash cycle, it can float up, allowing large food debris to get sucked directly into the wash motor.
âš Warning: Double-check the lock! A loose filter is the leading cause of premature wash motor failure, turning a free maintenance task into a $300-$500 repair.
Brand-specific notes
Some brands have known design quirks worth knowing about before you start.
Bosch & Thermador
Bosch dishwashers are famous for their ultra-quiet operation, which they achieve by completely eliminating the noisy internal hard-food disposer (macerator). Because of this, manual filter cleaning is absolutely mandatory. The filter is a prominent cylinder at the bottom center of the tub. Simply grasp the top handle, twist counter-clockwise, and lift. Bosch filters are highly effective but clog quickly if you don't scrape your plates.
Whirlpool, KitchenAid & Maytag
Many modern models from the Whirlpool family use a 'triple-filter' system. Look for the upper filter assembly that twists out, and carefully lift the lower flat filter. Older models (pre-2015) might have had a self-cleaning macerator, but almost all modern units require manual cleaning. KitchenAid models often have a very fine micro-mesh that is highly susceptible to hard water scaling, making vinegar soaks essential.
GE & GE Profile
GE filters often feature a distinct two-piece design. You usually need to squeeze two plastic tabs on the main filter cylinder to release it, then turn the fine filter counter-clockwise to remove the base plate. Be incredibly gentle with the GE fine mesh; the material is somewhat fragile, and OEM replacement filter kits can run anywhere from $40 to $65.
LG
LG dishwashers generally feature a large rectangular or circular filter plate with a central cylinder. The fine mesh on LG models is notoriously tight to catch tiny particles, which makes it highly susceptible to filming over with grease or hard water scale. If your LG is throwing an 'OE' (drain error) code, a blocked filter is the first thing you should check before assuming the drain pump has failed.
Samsung
On many Samsung models, the filter assembly is located slightly toward the bottom back of the tub rather than dead center. You'll need to twist the central knob and lift the entire unit out. Samsung's micro-mesh is prone to trapping grease, so using very hot water and a strong degreasing dish soap is essential to get the water flowing through the screen again.
What our techs see most often
About 30% of the 'my dishwasher isn't cleaning' calls we get in the San Fernando Valley and Orange County are just severely clogged filters compounded by our notorious hard water. A quick 10-minute scrub once a month saves homeowners a $150-$200 service call and keeps those pump motors running for years.
When to call a professional
- → If the filter mesh is torn, the plastic housing is warped, or pieces are missing, and you cannot confidently source or install a replacement part yourself.
- → If you have thoroughly cleaned the filter but the dishwasher still refuses to drain standing water, indicating a clogged drain hose, a blocked air gap, or a failed drain pump.
- → If you hear loud grinding, squealing, or rattling noises from the motor area during a cycle, even after removing all debris from the filter sump.
- → If you find metal shavings, heavy machine oil, or rust in the filter area, which points to a failing wash motor bearing or a damaged pump seal.
- → If the filter assembly is permanently jammed and cannot be unlocked by hand without risking breaking the plastic housing or the tub floor.
Related Dishwasher Troubleshooting
These troubleshooting guides cover problems this task can help solve.
Dishwasher Not Cleaning Dishes Properly: Fix Guide
Dishwasher Door Won't Latch or Stays Stuck: Fix Guide
Dishwasher Not Draining: How to Fix Standing Water
Dishwasher Soap Dispenser Won't Open or Release
Dishwasher Smells Bad: How to Remove Odors
Frequently asked questions
How often should I clean my dishwasher filter?
In Southern California areas with hard water (like Los Angeles or Ventura), we strongly recommend cleaning it once a month. If you pre-rinse your dishes heavily, you might stretch it to every 3-6 months, but monthly cleaning prevents hard water scale buildup and keeps odors at bay.
Can I run the dishwasher without the filter to flush the system out?
Absolutely not. Running the unit without the filter installed will allow large food chunks, glass, and debris to bypass the safeguards and enter the main circulation and drain pumps. This can quickly jam or destroy the pump impellers, leading to a costly $250-$400 repair.
Why does my dishwasher smell like a swamp even after I cleaned the filter?
If the filter is clean, the odor might be coming from a kinked drain hose, a clogged sink air gap (a $15-$30 DIY fix), or food trapped in the rubber door gasket. Wipe down the door seals and run a heavy cycle with a dishwasher cleaning tablet (like Affresh) or a bowl of white vinegar on the top rack.
How much does it cost to replace a damaged dishwasher filter?
If you accidentally tear the mesh or crack the plastic housing, a new OEM (Original Equipment Manufacturer) filter assembly typically costs between $30 and $75, depending on the brand and model. Bosch and KitchenAid filters are usually on the higher end of that price range.
Do all dishwashers have a manual filter that needs cleaning?
Most models manufactured after 2010 do. To meet stricter energy and noise standards, manufacturers removed the loud internal food choppers (macerators) and replaced them with manual wash filters. If your dishwasher is whisper-quiet, it almost certainly has a manual filter you need to clean.
Related Repair Guides
Dishwasher Not Cleaning Dishes Properly: Fix Guide
Dishes that come out gritty, filmy, or still flecked with food are usually not a detergent problem — they are a water problem. Hard water mineral deposits, clogged spray arm jets, and a starved water inlet valve cause roughly 80% of these complaints, especially in Southern California where calcium and magnesium levels run high. Most fixes take 30-90 minutes with no special parts.
Dishwasher Not Draining: How to Fix Standing Water
A pool of dirty water sitting at the bottom of your dishwasher after a cycle is one of the most common service calls we get. The good news: roughly 7 out of 10 cases trace back to a clogged garbage disposal connection or a blocked filter — both of which you can fix in under an hour without any special tools.
Dishwasher Smells Bad: How to Remove Odors
A stinky dishwasher usually means trapped food, a clogged filter, or hard water biofilm. Learn how to diagnose the root cause and banish those stubborn odors for good with basic household supplies.