Start here
The seal around a dryer door and drum keeps the airflow inside the drum where it can do work. When it fails, the machine still runs but much of its air bypasses the load. These platforms decide almost everything in software, so a sensor that drifts rather than fails keeps the appliance behaving plausibly and wrongly. Most of what follows is about conditions the machine is checking rather than parts that have failed.
Symptoms and near misses
- A rubbing or squealing noise as the drum turns — A seal that has come loose and is contacting the drum.
- Clothes taking noticeably longer to dry — Air bypassing the load is the commonest cause once the vent has been ruled out.
- Lint on the outside of the door or on the floor in front of the machine — Air escaping around the seal carries lint with it.
- NEAR MISS: long cycles with no lint escape and a hot vent — That is a venting restriction, not a seal.
What is usually behind it, in order
- Drum or door seal worn flat — The one to suspect first. It leads because felt seals wear from the first cycle onwards and nothing about the machine tells you when they have gone. Felt seals wear with every rotation and lose their contact gradually, so performance falls off over months rather than suddenly.
- Lint packed into the seal path — The second suspect. Debris holds the seal off its face and accelerates the wear that caused it.
- Restricted vent raising internal pressure — Third, and less common. Air that cannot leave through the duct leaves around the seal instead, so a duct fault presents as a seal fault.
- Seal detached or displaced — Fourth, and less common again. Adhesive fails with heat and age, and a lifted section both leaks and rubs.
- Body: The order below is what makes this page worth reading. It is a ranking rather than a measurement, and it carries no numbers because no fact bundle supports any.
Check in this order, and why
- Run a short cycle and feel around the door frame for escaping heat — Warm air at the door is the direct symptom.
- Look for lint outside the drum and on the floor — Lint travels with escaping air and marks the leak.
- Inspect the seal all the way round for flattening, gaps and tears — Do this with the machine isolated and the drum turned by hand.
- Body: The order below separates air leaving the wrong way from air that cannot leave the right way, because both produce the same complaint.
Step by step, safely
- Clear the lint filter and the whole vent run first — This must be ruled out before the seal is judged.
Tools: vacuum
- Isolate the machine and turn the drum by hand while inspecting the seal — Flattening, lifting and tears are all visible this way.
Tools: torch
- Check the door closes squarely and latches without being lifted — Alignment leaks look exactly like seal wear.
- STOP before removing the drum or refitting a seal — That is a strip-down and it is not an owner task on most machines.
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. Never run a dryer with the vent disconnected to test airflow, and never use the machine with a seal that is rubbing hard enough to smell, because friction on felt and lint is a fire risk rather than a noise complaint.
Where owner work ends
Call when the vent is clear and the seal is visibly flat, lifted or torn, or when the seal is rubbing the drum. Seal replacement is a strip-down on most machines and is worth having done properly, because a badly fitted seal produces the same complaint it was meant to fix. Mention any recent work in the room: taps, cables and hoses are the usual casualties.
What is out of scope
This page is written for the appliance class rather than for one Blomberg family or model line. Where a family- or model-specific page exists for your unit it is the more specific answer and should be preferred over this one; the brand and appliance hub linked below routes to everything more specific that exists today.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
