The short answer
A new noise from a Bosch WTH-series dryer is placed by rhythm before it is placed by part, and this platform changes the list of candidates: a ventless condensing dryer has running gear a vented dryer does not have. the heat-pump platform adds its own sounds on top, and some of them are normal. The ranking below is written for what is actually inside this cabinet rather than for dryers in general.
What you observe
- A squeal or a chirp once per drum revolution — A rotating contact somewhere behind the drum.
- A deep hum from the base that is not the drum — On this platform there is machinery under the drum, and it has its own note.
- An intermittent tick or gurgle between drum sounds — Water being moved, which is a normal part of how this machine works.
- NEAR MISS - a hiss or a soft gurgle for a minute at a time — That is condensate and refrigerant doing what they are meant to do on a condensing machine. It is not a fault and it does not need chasing.
Likeliest causes here
- Something loose in the drum or in the filter well — Coins, a zip pull, a wire from a bra and a button all make a noise out of all proportion to their size. First, because on these models it costs nothing to exclude and it explains most new noises.
- The load itself, or the machine not sitting level — A single heavy item and a floor that flexes together produce a walking, thumping machine that sounds broken. Second on these models: this cabinet is light enough that the floor under it matters.
- The blower wheel fouled or loose on its shaft — Lint packs one side of the wheel, it goes out of balance, and the note follows the airflow rather than the drum. Third on this family - it is constant rather than rhythmic, which separates it from the drum.
- The refrigerant circuit and its mounts — A heat-pump circuit has a compressor, and a compressor on tired mounts passes its vibration into the cabinet. It comes last here - a steady note that runs with the cycle rather than with the drum.
- Where this ranking departs from the brand-generic page — The cause that moves is something loose in the drum or in the filter well. It leads on this family because the heat here comes from a refrigerant circuit rather than from an element. That is a property of the platform rather than of the brand, which is why the page above this one cannot rank it the same way.
Check in this order
- Empty the drum, then look into the filter well with a light — Run a hand round the seal at the front of the drum as well. This is free and it ends most of these calls. It leads on these models because the construction puts it within reach before anything else on the list.
- Run the machine empty and rock each corner — If the noise vanishes without a load, the load was the noise. A cabinet that rocks needs its feet set, not a part.
- Listen for whether the note tracks the air or the drum — An airflow note is constant through a cycle; a drum note comes once per turn.
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. Do not reach into a drum that is still coasting, and let the machine cool before opening the lower access flap. Never run this machine with the rear panel off to listen to it; the air path only works closed.
When to call
Emptying the drum, clearing the filter well, setting the feet and emptying the tank are all owner ground here, and between them they resolve most new noises. The line is the back of the drum: a grind that rises with speed, a belt that has to come off, or a circuit note that persists with the drum stopped all mean the cabinet comes apart.
Nearest pages
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
