The short answer
A new noise from a condenser dryer points first at one thing: the heat-pump or condenser module is humming through the shell. Next on the list: the drum glides or the felt seal have worn through. Before anything else, work out whether the noise tracks the drum turning or the motor running — that single observation splits the list in half.
What you observe
- A sound the machine did not make when it was new — Note whether it is fast or slow before anything else.
- A continuous low hum that was always there and is now louder — The module runs whenever the machine does.
- A rasp or scrape once per drum rotation — Rotation-linked noise comes from the drum, not the motor.
- A high squeal that is worst at the start of a cycle — Temperature-dependent noise points at a dry bearing.
- NEAR MISS — a soft rush of air with no mechanical sound — That is the blower doing its job. Nothing to fix.
Causes, most likely first on this machine
- The heat-pump or condenser module is humming through the shell — First on this machine, because a ductless dryer carries a sealed refrigeration or condensing module that a vented one does not have. It hums continuously while the machine runs, and on a hard floor that hum couples into the room in a way owners of vented machines never hear.
- The drum glides or the felt seal have worn through — Ranked here because the glides are the fastest-wearing parts in the drum and the noise they make is very distinctive.
- The idler pulley is squealing — Ranked here because it is the commonest squeal in a dryer and it does not damage anything for a while.
- The machine is not sitting level — Last, and a spirit level settles it in minutes.
Check in this order, and why
- Note whether the hum is steady or has a beat in it — Steady is normal on this class; a beat is a finding.
- Note whether the noise tracks drum rotation or motor speed — Glides track the drum; a pulley tracks the motor.
- Note whether the squeal changes as the machine warms up — A dry bush squeals cold and often quietens hot.
- Push each corner and feel for rock — A cabinet that rocks at rest knocks under load.
What an owner can safely check
- Decide whether the noise is fast or slow — The drum turns slowly and the motor turns fast; the noise belongs to one of them.
About 10 min
- Put a dense mat under the machine and compare — Decoupling from the floor tells you how much was structure.
About 25 min
- Turn the drum by hand and listen for a scrape at one point — Report where in the rotation it happens.
About 10 min
- Run a short cycle and listen as the machine warms — Record whether the squeal fades, holds or worsens.
About 20 min
- STOP HERE if the noise survives every check above — Glides, an idler or a blower mean the cabinet comes apart. Service call.
Before you open anything
Safety
Unplug the machine or switch off its breaker before removing any panel. A capacitor can hold a charge after the power is off, and a dryer that has just cut out on temperature is hot inside long after it is silent. Empty and refit the condensate tank with the machine off; water and a live cabinet do not belong together. Never run the machine with the condenser unit out of its housing.
When to call a technician
Call once the machine is level, the duct is clipped clear and nothing loose is in the drum, and a rasp, squeal or rattle is still there. That means the cabinet comes apart. Call immediately if you hear metal grinding on metal, or if the noise arrived with a burning smell — a seized idler can scorch a belt in minutes.
Nearest pages of this class
What this page does not cover
This page is written for the brand and the machine class, not for one family or model line. Where a family- or model-specific page exists for your machine, it is the more specific answer and it is where to start. Deliberately absent: programme charts, capacity figures, condenser and board part identifiers and wiring colours, which differ between the condenser and heat-pump families.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
