Before you open anything
An Almison dishwasher that smells is holding residue somewhere in the drain path, most often under the filter and in the sump below it. The gasket channel round the door is the second place, and it is the one owners almost never look at. A machine cleaned in that order stops smelling within two or three cycles without any specialist product.
The observable signs
- A stale or sour smell when the door is opened cold — The classic biofilm signature. It is strongest after the machine has stood unused for a day or two.
- A drain smell that arrives during the cycle — Points further down the path, at the hose or the household waste rather than at the tub.
- Black or pink deposit in the gasket channel — Visible growth. Wipe a finger round the inside of the seal and look at it.
- NEAR MISS: a burnt smell during a hot programme — That is not mould. Something plastic has fallen onto the element, and it wants investigating today.
Where the fault usually sits
- Residue under the filter and in the sump — First, always. It is the warmest, wettest, most protected place in the machine and it holds exactly what a biofilm needs.
- The door gasket channel — Second, and routinely missed because the growth is out of sight behind the lip of the seal.
- Grease film on the tub walls and the arms — Third. It is what short, cool programmes leave behind, and it is the substrate everything else grows on.
- A sagging drain hose holding water — Fourth. It smells during the cycle rather than at rest, which is how it is told apart from the first three.
- The household waste connection — Last, and not the appliance's fault. If the sink smells too, so is this.
The order to work in, and why
- Open the door cold and smell it before running anything — A cold machine tells the truth. A machine that has just run smells of detergent whatever is growing in it.
- Pull the filter and look underneath — The most likely address, and the easiest to inspect.
- Run a finger round the inside of the door gasket — The second most likely, and the one nobody checks.
- Note whether the smell comes during the cycle or at rest — During the cycle moves the search to the hose and the waste.
The checks you can run yourself
- Strip and wash the filter stack in hot soapy water — Use a brush and get into the mesh. Rinsing under a tap is not enough once a film has formed.
Tools: brush, washing-up liquidAbout 20 min
- Clean the sump and the area under the filter by hand — Gloved fingers and a cloth. This is where the smell usually lives and it does not respond to cycles.
Tools: gloves, clothAbout 15 min
- Wipe out the gasket channel all the way round — Fold the seal back gently and clean both faces. Do not pull it out of its groove.
Tools: cloth, old toothbrushAbout 15 min
- Run the hottest empty programme with the machine clean — This clears the grease film that the manual cleaning loosened. Repeat monthly and the problem does not come back.
About 90 min
Safety first, and it is not boilerplate
Safety
Unplug the appliance or switch off its breaker before removing any panel — a capacitor can hold a charge after the power is off. Do not mix cleaning products in a dishwasher tub: bleach and any acid descaler together produce chlorine gas in an enclosed cabinet, and people have been hurt doing exactly this. Wear gloves in the sump, where glass fragments hide under the residue you are trying to remove.
What is not a homeowner job
Call when the machine has been properly cleaned, the gasket is clear and the smell returns within days, because at that point the residue is somewhere you cannot reach — usually the hose interior or the pump housing. Call a plumber instead if the sink smells as well, since a shared waste with a dry or damaged trap will make any appliance connected to it smell. And treat a burnt or electrical smell as a different page entirely: that one is not hygiene, and it is not something to schedule for next week.
Same problem, other brands
What this page does not cover
This page is written for the Almison dishwasher as a class rather than for one family or model. It names no filter part numbers, no gasket profiles and no cleaning-product 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 will show the filter and sump layout for that build. The household waste, the trap and the sink connection are plumbing and sit outside this page even when they are the 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.
