Whirlpool / Maytag Dryer AF or F4 E3 Error: Restricted Airflow Fix (#WP8577274)
Quick Answer: The AF (Air Flow) or F4 E3 error code on a Whirlpool or Maytag dryer indicates severely restricted exhaust airflow or a faulty Exhaust Thermistor (#WP8577274) reading false overheating temperatures.
⚠️ Lint Inside the Internal Trap Chute: Even if your wall pipe is clean, wet lint packs tightly inside the internal plastic lint chute directly beneath the filter screen, choking the blower wheel and triggering AF / F4 E3.
#1 Most Common Fix: Whirlpool Dryer Exhaust Thermistor Sensor
Official OEM Part Number: #WP8577274
⏱️ Install Time: 15 Minutes | 💰 Avg Cost: $13.99 – $19.99
Step 1: Free 2-Minute Reset & Test
- Pull out the lint screen and wash it with hot water and dish soap—if water pools on the mesh instead of running straight through, invisible dryer sheet wax is blocking airflow!
- Disconnect the rear exhaust hose and clean out the wall vent pipe.
- If AF / F4 E3 persists with the exhaust hose disconnected, replace the Exhaust Thermistor (#WP8577274).
Step 2: Symptom & Part Number Lookup Table
| Symptom | Required OEM Part | Difficulty & Cost | Action |
|---|---|---|---|
| Vents are completely clear, but dryer still flashes AF or F4 E3 on every heated load Cause: Drifted resistance in NTC Exhaust Thermistor | Whirlpool OEM Exhaust Thermistor#WP8577274 | Easy DIY (15 min) Est: $15.99 | Check Price on Amazon → |
| Rattling noise from blower housing or weak air coming out the back port Cause: Stripped plastic center hub on Blower Wheel | Whirlpool Dryer Blower Wheel#WP697772 | Moderate DIY (25 min) Est: $19.50 | Check Price on Amazon → |
Frequently Asked Questions
Can I keep using my Maytag or Whirlpool dryer when AF is flashing?
Pressing Cancel clears AF temporarily, but running the dryer with restricted airflow will blow the non-resettable thermal fuse (#WP3392519), leaving the dryer completely dead.