What does EF1 mean?
Restricted exhaust airflow detected.
Common causes
- Lint buildup in duct
- Crushed duct
- Blocked exterior vent
Diagnostic & testing steps
- 1. Clean lint filter
- 2. Clean exhaust duct
- 3. Check exterior vent
- 4. Verify duct length and elbows
OEM parts & part numbers
Exhaust Duct
Safety warning
⚠️ Blocked vents are fire hazard
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