FixByModel
AF

Whirlpool AF: Restricted airflow — clogged lint screen or vent

AF warns that exhaust airflow is restricted, so the dryer runs longer and hotter than it should. The cycle keeps going, but it is telling you the lint screen or vent path needs clearing.

DIY fix

By the FixByModel editorial team · Verified 2026-09 · Researched against manufacturer support & repair references (below)

Most likely causes

  1. Clogged or lint-caked lint screen
  2. Blocked, crushed, kinked, or lint-filled exhaust vent duct
  3. Too many bends or an over-long vent run
  4. Obstructed or stuck exterior vent flap
  5. Improperly installed or oversized ductwork
The airflow path — check in this order
1Lint filter
2Blower / lint housing
3Vent hose
4Wall duct
5Exterior vent

Schematic illustration of a typical dryer — not your exact model.

Before you start — unplug the dryer, and on a gas model shut off the gas supply. Let it cool first — the drum, heater and exhaust can be hot. If a step involves the heating element, wiring, or opening the cabinet and you're unsure, stop and call a qualified technician.

Step-by-step fix

1Clear the displayTouch any key to clear AF; then address the airflow so it does not return.
2Clean the lint screenRemove and wash the lint screen every load; if water beads on it, scrub off fabric-softener film.
3Inspect the ventDisconnect and clean the full exhaust duct from the dryer to the outside wall, removing lint buildup.
4Straighten the ductingRemove kinks and crushes, and keep the run as short and straight as possible with rigid or semi-rigid metal duct.
5Check the outside flapConfirm the exterior vent hood opens freely and is not blocked by lint, nests, or debris.

Still showing AF?

If you’ve worked through every step and AF keeps returning, an internal part likely needs testing and replacement. That’s a job for a qualified appliance technician, who can measure the suspect part against the service-manual spec before replacing it.

Which models this applies to

Whirlpool dryers. Whirlpool dryers that show AF (equivalent to the F4E3 code on newer models); airflow warning, not a component failure.

FAQ

What does Whirlpool AF mean?

Restricted airflow — clogged lint screen or vent. AF warns that exhaust airflow is restricted, so the dryer runs longer and hotter than it should. The cycle keeps going, but it is telling you the lint screen or vent path needs clearing.

What causes Whirlpool AF?

The most likely cause is clogged or lint-caked lint screen. Other causes include Blocked, crushed, kinked, or lint-filled exhaust vent duct; Too many bends or an over-long vent run; Obstructed or stuck exterior vent flap; Improperly installed or oversized ductwork.

Can I fix Whirlpool AF myself?

Usually yes. Start by working through the steps above, beginning with: touch any key to clear af; then address the airflow so it does not return.