Whirlpool Dryer Error AF: Airflow Restriction
The AF code (or F4E3 on digital-display models) indicates that drying airflow is restricted, usually from lint buildup in the filter or exhaust duct.
Common symptoms:
- Clothes come out damp or take much longer to dry
- "Clean filter" or AF indicator lights up
- The dryer feels hotter than usual on the outside
Probable causes:
The accumulated lint layer blocks hot air passage, even if the filter looks only partially full.
The duct running outside accumulates lint over time or is kinked behind the dryer, drastically reducing airflow.
On ventless dryers, a full tank can also trigger similar warnings due to system overheating.
Safe Inspection Checklist (Check off when completed):
Remove the filter and pull off all lint by hand; then wash it with warm soapy water to clear the fabric softener residue clogging the pores, and let it dry fully.
Disconnect the duct at the back and check it isn't crushed or packed with lint. A vacuum cleaner helps pull out debris built up inside.
On condenser models, remove the front tank, empty it completely, and reseat it firmly before starting a new cycle.
If AF keeps appearing after cleaning the filter and duct, an airflow sensor may be faulty or the outside vent could be blocked at an inaccessible point, requiring a technician or duct specialist.