What does d90 mean?
Flow sensor detected exhaust vent is approximately 90% restricted.
Common causes
- Severely clogged duct
- Collapsed duct section
- Complete exterior vent blockage
- Dryer vent crushed against wall
Diagnostic & testing steps
- 1. Clean entire duct system thoroughly
- 2. Check for collapsed duct sections
- 3. Verify exterior vent is clear
- 4. Consider professional vent cleaning service
- 5. Replace transition duct if damaged
Tools required
- Vent cleaning brush kit
- Vacuum
- Flashlight
OEM parts & part numbers
Exhaust Duct, Transition Duct
Part numbers: 4986ER0004G
Safety warning
⚠️ FIRE HAZARD - do not operate dryer until vent is cleared
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