Dryer displays E04 and does not heat; cycle may continue with only cool air.

Safety first: Unplug the dryer and allow it to cool for at least 30 minutes before working near the heater or ducting.

• Clean lint filter: Remove the door filter and any secondary filter. Wash with warm soapy water, dry thoroughly, and reinstall.
• Clean condenser/heat exchanger: On condenser and heat pump models, open the lower front flap and remove the condenser unit. Rinse under running water to remove lint and fluff. Allow to drain and refit correctly.
• Check airflow paths: Inspect the air intake grilles and internal ducts (if accessible) for lint buildup. Vacuum gently without damaging sensors.
• Reset thermostat (if fitted): Some Montpellier heaters have a manual reset thermostat (small button on a thermostat body). With power off and rear panel removed, press the reset button if present. If it trips repeatedly, investigate airflow and heater condition.
• Test run: Restore power and run a timed warm cycle while monitoring for normal heat. If E04 reappears quickly, the thermostat, thermal fuse, or heater assembly may need replacement.