The short answer
An AooDen dishwasher that smells is holding a greasy residue somewhere in the wash and drain path, most often under the filter, in the sump, and in the door gasket channel. The fix is mechanical rather than chemical: strip and wash those places by hand, then run a hot cycle. Products help afterwards; they do not substitute for the hour with a brush.
What owners describe
- A sour smell on opening a machine that has stood shut — Biofilm. Strongest when the machine has been closed and unused for a day or two.
- A drain smell that appears while the machine runs — Further down the path: the hose, or the household waste it connects to.
- Visible dark or pink growth in the gasket channel — Direct evidence, and the place owners almost never inspect.
- Plates smelling faintly after a wash — Redeposition. The machine is washing in what it should have drained away.
- NEAR MISS: a hot plastic smell during the cycle — Not hygiene. Something has fallen onto the element and it needs finding today.
Ordered by likelihood
- Grease film from cool short programmes — First on this page because it is the underlying condition rather than a component fault, and every other cause grows on top of it.
- Residue under the filter and in the sump — Second, and the specific address of most smells.
- The door gasket channel — Third, out of sight behind the seal lip, and routinely missed during cleaning.
- A drain hose holding water in a sag — Fourth. It smells during the cycle rather than at rest, which is the distinguishing clue.
- The household waste connection — Last, and not the appliance at all. If the sink smells too, this is your answer.
Work down this list
- Smell the machine cold before running anything — A machine that has just run smells of detergent, whatever is living in it.
- Lift the filter and look and smell underneath — The most likely address and the easiest to check.
- Fold back the door gasket and inspect the channel — The second most likely and the one nobody looks at.
- Note whether the smell is at rest or during the run — During the run moves the search into the hose and the waste.
The checks you can run yourself
- Strip the filter stack and wash it in hot soapy water — Brush the mesh rather than rinsing it. A rinse moves the smell around; a brush removes it.
Tools: brush, washing-up liquidAbout 20 min
- Clean the sump and the area beneath the filter by hand — Gloved. This is where the smell usually lives and no cycle reaches it.
Tools: gloves, clothAbout 15 min
- Clean the gasket channel all the way round — Fold the seal back gently and wipe both faces without pulling it out of its groove.
Tools: old toothbrush, clothAbout 15 min
- Run the hottest empty programme once the machine is clean — This strips the grease film that the hand cleaning loosened. Monthly thereafter keeps it away.
About 90 min
Before you touch it
Safety
Unplug the appliance or switch off its breaker before removing any panel — a capacitor can hold a charge after the power is off. Never combine bleach with an acid descaler in the tub: together they release chlorine gas inside a closed cabinet, and that has hurt people doing exactly this job. Wear gloves in the sump, where glass fragments sit in the residue you are trying to lift out.
When to stop and book someone
Call when the machine has been stripped, cleaned and run hot and the smell returns within a week, because the residue is then somewhere unreachable, typically inside the drain hose or the pump housing. Call a plumber instead if the sink smells too, since a dry or damaged trap makes everything connected to it smell. And treat any burnt or electrical smell as a different problem entirely: that one is not hygiene and it does not wait for the weekend.
Nearest pages of this class
Where this page stops
This page is written for the AooDen dishwasher as a class rather than for a family or a model line. It names no filter parts, no gasket profiles and no cleaning brands, because the first two differ across builds under this badge and the third is not the appliance's business. Where a family- or model-specific page exists it shows the filter and sump layout for that build. The sink waste, the trap and the plumbing under it stay outside this page even when they are the actual source of the smell.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
