The short answer
On a European built-in dishwasher of this platform, most new noises come from the sump rather than the motor. A rattling non-return flap or a fragment lodged against the drain impeller accounts for the majority, and both are reachable through the tub floor with the filter out and the power off. A genuine bearing failure sounds different, is continuous, and is the last thing to suspect rather than the first.
What you are seeing
- A rapid chattering or fluttering during the drain step only — Note: The non-return flap in the sump is loose or held partly open by debris. It is the most common new noise on this platform.
- A hard grinding that rises with the pump on fill and wash — Note: Something solid is against an impeller. Glass fragments and fruit stones are the usual culprits.
- A rhythmic knocking that matches the spray arm going round — Note: The arm is striking a load item, or the upper arm feed tube has unseated at the back wall.
- A single loud bang at the moment the machine takes water — Note: Valve hammer at the inlet head, which is about the plumbing rather than the machine.
- A drumming or booming through the worktop — Note: The cabinet is not secured to the counter, or the feet are not carrying the machine evenly.
- A continuous hum with no water movement at all — Note: That is not a noise fault. The machine is likely holding on its flood protection; read the cycle page.
Ranked causes on this brand
- Non-return flap in the sump chattering or held open by debris — Why this rank: First because this platform uses a small hinged flap in the sump to stop drain water returning, it sits directly under the filter where debris collects, and it is the noise owners describe most often.
- Drain impeller obstructed by glass, a stone or a label — Why this rank: Second because the drain pump on this platform draws from the sump through a short path with no macerator ahead of it, so anything that gets past the filter reaches the impeller directly.
- Circulation pump impeller with a foreign object against it — Why this rank: Third: it produces the same grinding but through the whole wash rather than only on drain, which is how you tell the two apart by ear.
- Spray arm striking the load, or the upper arm feed tube unseated — Why this rank: Fourth because the upper arm is fed by a tube that clips to the back wall, and it pops off when the upper basket is pulled out hard.
- Machine not secured to the worktop or standing unevenly — Why this rank: Fifth: a European built-in is designed to be screwed to the underside of the counter through brackets, and an unsecured one transmits pump noise into the worktop as a drum.
- Circulation pump bearing wear — Why this rank: Last because it is the only cause here that needs a pump, it develops slowly rather than appearing overnight, and every cause above it is far more common and free to check.
What to check, in order
- Listen and note which step of the cycle the noise happens in — Why: Drain-only, wash-only or both is the single most useful piece of information, and it separates the top three causes immediately.
- Twist out the cylindrical filter and look into the sump with a torch — Why: The flap and the mouth of the drain path are both visible from here without removing anything else.
- Feel the flap with a fingertip and check it hinges freely and closes flat — Why: A flap held open by a fruit stone or a shard is both the noise and, later, a smell complaint.
- Spin each spray arm by hand through a full turn with the baskets loaded as you normally load them — Why: A knock that reproduces by hand is a load or a feed-tube problem and needs no parts.
- Press down on the front corners of the machine and try to rock it — Why: Movement means the brackets are not holding it to the counter and the worktop is amplifying normal pump noise.
Checks you can do safely
- Run a short cycle and write down whether the noise happens on fill, during wash, during drain, or throughout. — Tools: none — Time: half an hour of listening
- Switch the machine off at its isolator, open the door, remove the lower basket and twist out the cylindrical filter assembly. — Tools: none, or a coin for the filter collar — Time: ten minutes
- With a torch, inspect the sump floor and the non-return flap. Lift out any glass, stones, seeds or labels with fingers or a plastic scoop. — Tools: torch, plastic scoop — Time: a quarter of an hour
- Check the flap hinges freely and seats flat when released, then wash the filter under a hot tap with a soft brush. — Tools: soft brush — Time: ten minutes
- Refit the filter, then spin both spray arms by hand through a full turn with the baskets loaded normally and note anything they touch. — Tools: none — Time: five minutes
- Reach up to the back of the upper basket and confirm the arm feed tube is fully engaged in its coupling on the rear wall. — Tools: none — Time: five minutes
Before you open anything
Safety
Switch the machine off at its isolator or breaker before reaching into the sump. Assume there is broken glass in there: use a torch and a plastic scoop rather than bare fingertips, and never sweep a hand blindly around the drain mouth. The inlet hose on this platform carries mains wiring inside its outer sleeve to a solenoid at the tap end, so it must never be cut, shortened, kinked or repaired, and it must not be handled with the machine live. Do not run the machine with the kick panel removed to listen to it. Unplug the appliance or switch off its breaker before removing any panel. A capacitor can hold a charge after the power is off. — Id: unplug-before-service
Where the service line falls
The sump and the flap are clear, both spray arms turn freely, the machine is secured, and the grinding continues through the whole wash. The noise is a continuous rumble or whine that is present the moment the pump starts and does not change with the load, which points at bearing wear. You can see water in the base pan below the tub, in which case a leak is feeding the machine flood protection and that comes before any noise work. The noise arrived together with a burning smell or a protection device tripping, which is an electrical matter and not a mechanical one. The machine needs the pump removed, because on a discontinued badge the replacement has to be cross-referenced to a group-sibling platform rather than ordered by name.
Nearest pages
What this page does not cover
This page is generalized across families and models on this European built-in platform. It does not cover a specific model family, and it does not cover slimline or compact variants, fully integrated units with a different door and bracket arrangement, or any model whose sump uses a macerator ahead of the drain pump. Identify your machine from the rating plate on the edge of the door or inside the tub rim rather than from the badge, because this manufacturer supplied the same platform under several group badges and a parts desk cross-references by platform, not by name.
Links down: - [Fagor Dishwasher: Will Not Drain](/blog/fagor-dishwasher-drainage-failure) - [Fagor Dishwasher: Odor or Mold](/blog/fagor-dishwasher-smell-mold)
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
