Fine dust escapes from the exhaust air; the air seems dusty despite the filter being installed.

Safety first: Remove the battery and wear respiratory protection when handling contaminated filters.

• 1. Verify filter type: Confirm that the installed filter is the correct Festool HEPA or main filter specified for the model.
• 2. Inspect filter: Remove the filter and check for tears, holes, or separation from the frame. Replace if any damage is found.
• 3. Check seating and seals: Ensure the filter sits flat in its housing and that all sealing edges contact the housing surfaces. Clean dust from sealing surfaces.
• 4. Replace if in doubt: If you suspect filter damage or age-related degradation, replace the filter. Do not attempt to repair torn filter media with tape or glue.