Short answer
- Wash the removable filter at the sink with soap, water, and a soft brush, every few months (Bosch, GE).
- Clear blocked spray arm holes with a toothpick; rinse the arms under a tap.
- Run an empty monthly cycle with a dishwasher cleaner, or an occasional vinegar rinse per your manual.
- Wipe the door edges and rubber seal, where crumbs and moisture collect.
- Never mix bleach with vinegar or ammonia. The combination creates toxic gas.
A dishwasher washes your dishes, but it does not fully wash itself. Food scraps collect in the filter, grease films the tub walls, and minerals from hard water build up on everything the water touches. The warning signs are gritty residue on glasses, cloudy film, and a musty smell when you open the door. The fix is mostly mechanical rather than chemical: pull out the parts that trap debris, wash them at the sink, wipe the surfaces the spray cannot reach, then run one empty cleaning cycle. This guide follows the published care guidance from Bosch, GE Appliances, and Whirlpool, dirtiest parts first.
Step 1: Clean the Filter
The filter sits at the bottom of the tub, usually beneath the lower spray arm. Pull out the bottom rack to reach it. On most current models the filter is a cylinder that twists and lifts out; some designs add a flat fine filter plate underneath. A few older models use a built-in food disposer instead, with nothing to remove. Check your manual for which design you have.
Wash the filter at the sink. Bosch’s care instructions say to clean it under running water with soap and a soft brush. GE Appliances Factory Service recommends soaking it in hot, soapy water and scrubbing with a sponge or brush, then checking that the drain area underneath is clear before refitting. Be gentle: the mesh is fine, and torn mesh lets food straight through.
Refitting matters as much as washing. Whirlpool’s use and care guides warn owners not to operate the dishwasher without the filters properly installed and locked into place. A loose filter lets food recirculate onto your dishes and work its way toward the pump.
How often? Bosch advises every few months, and GE gives the same interval for the drain filter. If dishes come out gritty or a smell appears, do not wait for the calendar: check the filter first.
Step 2: Clear the Spray Arms
Spray arms do the actual washing, and a handful of blocked holes can leave a whole rack dirty. The lower arm usually lifts off or unscrews. The upper arm is often fixed to the underside of the top rack with a locking nut, as described in Bosch’s manual.
Hold each arm under a tap and watch the holes. Bosch’s guidance: run water through the arm, and if any holes are blocked, use a toothpick to loosen the debris, then rinse again. Refit the arms and spin each one by hand; it should rotate freely. Bosch suggests this check every few months, in step with the filter.
Step 3: Wipe the Interior, Door Edges, and Seal
With the machine empty and cool, wipe the tub walls and floor. Whirlpool’s interior method is a paste of powdered dishwasher detergent and water on a damp sponge, or liquid dishwasher detergent on a damp sponge. Whirlpool cautions against other types of cleanser inside the machine, because they may cause foaming or sudsing.
Pay attention to the door. Bosch’s manual notes that the outer edges of the inside door panel collect debris from loading and should be cleaned regularly; the spray barely reaches them. Then wipe the rubber door seal and inside its folds with a damp cloth. The seal traps crumbs and moisture, and it is a common spot for dark mold growth. A soft toothbrush helps in the folds. For the exterior, a soft damp cloth and mild detergent are enough (Whirlpool).
Step 4: Run a Cleaning Cycle
Two manufacturer-backed options cover the inside surfaces you cannot wipe.
A dishwasher cleaner product. GE Appliances recommends a dishwasher cleaning solution once a month to remove mineral deposits, scale buildup, and hard water stains, and a citric acid cleaner every few months to clean and deodorize. Whirlpool likewise recommends a monthly maintenance product for hard water filming.
A vinegar rinse. GE’s method: pour one cup of white vinegar into the bottom of the empty dishwasher and run the hottest cycle, repeating every few months or as needed. Whirlpool’s method: place two cups (500 mL) of white vinegar in a glass or dishwasher-safe measuring cup on the bottom rack and run a complete cycle using an air-dry or energy-saving dry option, with no detergent. Amounts differ by brand, so follow your own manual. One caution from Whirlpool: vinegar is an acid, and using it too often could damage your dishwasher. Treat it as an occasional rinse, not a weekly habit, and never add detergent to a vinegar cycle.
Why a Dishwasher Smells, and What Fixes It
Most dishwasher odors come from a short list of causes. The most common is food debris rotting in the filter: GE links a clogged drain filter directly to a smelly dishwasher. Grease film on the interior, mold in the damp folds of the door seal, and standing water left by poor drainage are the other usual suspects.
Work through them in order. Clean the filter. Wipe the seal. Run a cleaning cycle. Then check the tub floor after a normal wash: it should be nearly dry. If water is still pooled there, check the drain area for debris. If your installation has a drain air gap (the small fitting beside the faucet on some sinks), Whirlpool advises cleaning it periodically to ensure proper drainage. Persistent drainage problems are a repair issue, not a cleaning one.
Prevention is mostly loading habits. GE recommends scraping large pieces of food off dishes before loading, rather than sending them in for the filter to catch. The dishwasher shares a drain with the kitchen sink, and Whirlpool’s care guide advises running the garbage disposal, if you have one, before a load so that shared drain is clear.
What Not to Use
Never mix bleach with vinegar or ammonia. West Virginia University Extension, citing CDC guidance, warns that mixing bleach with vinegar or ammonia creates toxic fumes that can cause coughing, shortness of breath, and chest pain. Bleach plus vinegar produces chlorine gas; bleach plus ammonia produces chloramine gas. Never follow a vinegar rinse immediately with a bleach product either: rinse thoroughly and let the machine air out between any two products.
Bleach in a stainless steel tub. Whirlpool’s cleaning guide is blunt: if the interior of your dishwasher contains stainless steel, avoid bleach completely, because it can damage the finish. If your manual permits bleach for a mold problem in a plastic tub, that is the exception. The manual decides, not habit.
Hand dish soap and general household cleansers. Whirlpool restricts interior cleaning to dishwasher detergent precisely because other cleansers can foam and suds. Hand dish soap is the classic mistake: a small amount can fill the tub with suds that leak onto the floor.
Abrasive powders, scouring pads, and stiff brushes. These scratch the tub finish and can damage the fine filter mesh. Every manufacturer method above uses a soft cloth, sponge, or soft brush.
Drain cleaner or oven cleaner. Never put these in a dishwasher. They are far too caustic for its seals, pumps, and finishes.
A Simple Maintenance Routine
Monthly: Run a cleaning cycle with a dishwasher cleaner product, as GE and Whirlpool both recommend monthly maintenance. Wipe the door edges and seal while you are there.
Every few months: Wash the filter at the sink, check and clear the spray arms, and run a vinegar rinse if white film or spots are building up, per the Bosch and GE intervals above.
Every load: Scrape plates before loading, and run full loads without packing dishes so tightly that they block the spray arms. Full loads conserve water and electricity, but only if the water can circulate.
Frequently Asked Questions
How often should I clean my dishwasher?
Manufacturers cluster around the same answer: a cleaning cycle about once a month, filter cleaning every few months, and spray arm checks on the same cycle. GE specifies a cleaning solution once a month, and Whirlpool recommends a monthly maintenance product. Heavy use or hard water argues for the shorter end of those ranges.
Can I use vinegar instead of a dishwasher cleaner?
Yes, as an occasional rinse. GE uses one cup poured into the empty tub; Whirlpool uses two cups in a container on the bottom rack. Whirlpool also warns that too-frequent vinegar use could damage the machine, so rotate it with a made-for-purpose cleaner, or choose the cleaner.
Is bleach safe in a dishwasher?
Only in narrow circumstances. Whirlpool advises avoiding bleach entirely when the tub or interior parts are stainless steel. Whatever your tub material, never let bleach meet vinegar or ammonia, including residue from a previous cycle, because the gases produced are toxic.
Why are my dishes still dirty after I cleaned the machine?
Check the two mechanical causes first: a filter that is not locked back into place, and spray arm holes that are still blocked, or arms that cannot spin because a tall item is in the way. Both are more common than pump failure.
Conclusion
A clean dishwasher comes down to four habits: wash the filter at the sink every few months, keep the spray arm holes clear, wipe the door edges and seal that the spray cannot reach, and run a monthly cleaning cycle. Follow your manual’s amounts for vinegar or cleaner, keep bleach away from stainless steel, and never mix cleaning chemicals. Do that, and the machine goes back to its actual job: cleaning the dishes instead of redistributing last week’s dinner.
Keep reading: How to Clean a Porcelain Sink Without Scratching the Enamel
Sources & references
- Bosch Home Appliances (bosch-home.com), Dishwasher Cleaning & Maintenance: filter and spray arm methods and intervals.
- GE Appliances Factory Service (repair.geappliances.com), Dishwasher Maintenance Tips: monthly cleaner, citric acid cleaner, one-cup vinegar rinse, drain filter care, scraping before loading.
- Whirlpool Use & Care Guides, Dishwasher Care: interior cleaning with dishwasher detergent, two-cup (500 mL) vinegar rinse, monthly maintenance product, filter installation warning, frequent-vinegar caution, drain air gap cleaning.
- Whirlpool, How to Clean Your Dishwasher (care guide): avoid bleach in stainless steel interiors; shared drain advice.
- West Virginia University Extension (extension.wvu.edu), Home Cleaning Safety, citing CDC guidance: bleach mixed with vinegar or ammonia creates toxic fumes; disinfectants should carry an EPA Registration Number.
