Dryer stops mid-cycle with E04; unit may feel very hot inside.

Safety first: Disconnect power and allow the dryer to cool completely before working on it.

E04 indicates the dryer has overheated beyond safe limits.

• Clean the lint filter: Remove the lint filter from the door opening and clean thoroughly with warm water and a soft brush if clogged with fabric softener residue. Dry completely before reinstalling.
• Clean condenser/heat exchanger (if applicable): On Blomberg condenser and heat pump dryers, open the lower front flap, remove the condenser unit, and rinse it under running water to clear lint from the fins. Let it dry and reinstall.
• Check exhaust duct (vented models): Disconnect the vent hose from the back of the dryer. Inspect for crushed sections, lint clogs, or bird nests at the wall outlet. Clean or replace the duct as needed and avoid long, restrictive runs.
• Inspect thermostats and thermal cut-outs: Access the heater housing from the rear. Test the high-limit thermostat and thermal fuse for continuity. Replace any open components with OEM-rated parts.
• Check heater relay operation: If the heater remains on when it should be off, the relay on the main control may be stuck closed. This is a board-level fault and usually requires control board replacement by a professional.
• After cleaning and repairs: Reassemble, restore power, and run a test cycle on low heat. Monitor for normal temperature and verify that E04 does not reappear.