What this means on these models
Noise from a WAW washer is a load question before it is a bearing question. On a drum machine of this construction an unbalanced load, a cabinet off its feet or transit bolts still in place will all produce a noise owners describe as a failing bearing, and none of them needs a part.
The observable tells
- A squeal on the first rotation of every wash — Usually the door seal or a belt taking up its slack rather than anything structural.
- A metallic rattle at low drum speed — Something loose is riding in the drum or has passed the seal into the sump. It is audible at slow speeds because nothing is masking it.
- A humming machine that does not turn at all — The motor is being asked to move a drum that will not move, and that is a jammed-drum fault rather than a noise fault.
- Loud only on one programme — Different programmes use different spin speeds, so this normally means the noise has a speed threshold rather than a cause of its own.
- The machine walks across the floor on spin — Feet, floor or load. The noise is a symptom of the movement, and stopping the movement stops the noise.
The ranking that applies to this platform
- Unbalanced or under-loaded drum — First on this family by frequency: a small heavy item alone in a large drum cannot be balanced, so the machine either bangs or refuses to reach speed.
- Foreign object in the sump or between drum and tub — Coins, wires and clips pass the seal and grind continuously. It ranks high here because it is common and because it does real damage if left.
- Transit bolts still fitted or partly backed off — Only on a machine that has been moved, but on such a machine it is the very first thing to check and the noise is unmistakable.
- Drain pump impeller fouled — Produces a harsh noise on drain only, which is why the timing of the noise within the cycle matters so much on this diagnosis.
Check in this order, and why
- Listen for whether the noise tracks drum speed — Speed-tracking noise is mechanical and in the rotating assembly; constant noise is not, and that split is the most useful one you can make.
- Rock the cabinet at each corner — Any movement means a foot is not carrying weight, and everything downstream of that is unreliable until it is fixed.
- Press and release each cabinet panel while the noise runs — A rattle that changes under your hand is panel resonance and needs no part at all.
- Run a spin with the drum empty — It removes the load variable entirely, which is the single biggest source of noise on this family, and it costs one short cycle.
What to do before you start
Safety
Power off at the breaker before any access panel is lifted. Water on a kitchen floor beside a machine that is still plugged in is the hazard here, far more than anything inside the cabinet.
Models in the WAW family
Reference| Model number | Family key |
|---|---|
| WAW28420AU | bosch:washer:waw |
| WAW28440AU | bosch:washer:waw |
| WAW285H1UC | bosch:washer:waw |
| WAW285H2UC | bosch:washer:waw |
| WAW28620AU | bosch:washer:waw |
| WAW28640AU | bosch:washer:waw |
| WAW28790AU | bosch:washer:waw |
Where the owner fix ends
The service call starts where the wiring does. Checking a filter, a hose or a load is fine; tracing a harness behind the tub of a machine that is plumbed in is not, and a technician does it in one visit.
Nearest pages of this class
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
