The answer in three sentences
Poor results from an AEG F dishwasher almost always mean water is not reaching the load with enough force, and the reasons are within reach. The machine cleans by throwing hot water at the dishes through spinning arms. Bad results mean the water is not hot enough, the arms are not delivering it, or the load is shielding itself. The table below names four models under this family key. They are near enough alike that the fault presents the same way on each; the divergence is in part numbers rather than in how you find it.
What comes out of the machine
- Grit and food debris redeposited on the dishes — The filter is passing debris back into the wash rather than holding it.
- A chalky film on glasses and on the inside of the door — Water hardness and detergent chemistry, not a mechanical failure.
- The upper rack is poor while the lower rack is clean — The upper arm is not getting water, which narrows this to the feed or the arm.
- Dishes emerge barely warm and still wet — The water is not reaching temperature, which damages cleaning and drying together.
- NEAR MISS — dirty dishes with water left standing in the base — Drainage is the fault; the drainage page for this family covers it.
Where the wash is being lost, most likely first on the F line
- Blocked jets, or an arm that cannot turn — Every clogged jet takes pressure from the rest, so delivery declines over months, and an arm fouled by a tall item simply stops turning altogether. All four models under the F key are built the same way here, so an ordering that fits one of them fits the rest.
- The filter and sump loaded with debris — It is the designed trap and the part owners are least likely to have ever removed, so debris builds until the machine is recirculating its own dirt — which is precisely the complaint that brings people here.
- How the machine is loaded — A single tray or a tall pot shadowing an arm removes the wash from a whole rack, and it is the one cause on this page with no failed part in it.
- Water temperature, detergent and rinse aid — Detergent needs heat to work, so a machine drawing cold water or running a short programme cleans badly with everything mechanically perfect, and hard water adds the film.
The order to work through on these models
- Take each arm off and hold the jets up to the light — A blocked jet is seen rather than inferred, and the arms lift off by hand on most machines.
- Lift out the filter assembly, rinse it and clear the sump — The single most effective thing an owner can do on this fault.
- Spin both arms by hand with the racks loaded and see what they strike — Costs nothing: if an arm stops on an item, that is your answer.
Models in the F family
Reference| Model number | Family key |
|---|---|
| F8242FI | aeg:dishwasher:f |
| F8242FI-18 | aeg:dishwasher:f |
| F8642FI | aeg:dishwasher:f |
| F8642SS | aeg:dishwasher:f |
Before you open anything
Safety
Unplug the appliance or switch off its breaker before removing any panel — a capacitor can hold a charge after the power is off. Close the isolating valve before undoing any hose, and expect water in the sump even after a cycle. Wash water and the heating element are both hot at the end of a cycle, so let the machine cool before reaching into the base. Leave the door latch and its switch exactly as fitted: they stop the wash when the door opens.
The line between an owner check and a service call
Call a technician when the filter, the arms, the loading and the water temperature are all proven and results are still poor, because the next suspects are the wash pump and the inlet under the machine. Call sooner if you find water outside the cabinet, if the protective device operates during the heated stage, or if anything smells of burning during a programme.
The rest of this family, fault by fault
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Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
