Whirlpool Dryer F22 Error Code — What It Means
On Whirlpool dryers, the F22 code signals a problem in the outlet thermistor or temperature sensor circuit. The control board detects that the thermistor is open, shorted, or reporting an implausible temperature reading. The dryer will typically shut down after about a minute when this fault occurs. (Note: On Whirlpool front-load washers, F22 means a door lock issue, not a thermistor fault.)
The outlet thermistor is a temperature-sensing resistor mounted in the dryer’s exhaust path. It tells the control board how hot the exhaust air is so the heater can cycle correctly. When the thermistor or its wiring fails, the control loses its temperature reference and throws F22 to prevent overheating or unsafe operation.
Common Causes
- Failed outlet thermistor The thermistor itself degrades over time, develops an open circuit, or shorts internally.
- Loose or corroded connector Vibration or moisture causes the thermistor plug or connector pins to lose contact or corrode.
- Damaged wiring harness Wires between the thermistor and control board are pinched, cut, or shorted to ground.
- Control board fault The machine control board misreads the thermistor signal or has a failed input circuit.
Step-by-Step Fix
- Power down the dryer at the circuit breaker for five minutes, then restore power and run a timed dry cycle to see if F22 returns. This reset step clears any transient faults.
- Unplug the dryer and pull it away from the wall. Remove the top or rear panel (depending on your model) to access the outlet thermistor, usually mounted on the blower housing or exhaust duct.
- Inspect the thermistor connector and wiring harness for loose pins, corrosion, or damage. Disconnect the thermistor plug and examine both the sensor terminals and the harness socket.
- Measure thermistor resistance with a multimeter set to ohms. Touch the probes to the thermistor terminals (with the sensor at room temperature). Compare your reading to the resistance table in your model’s service manual. A reading of open (infinite ohms) or near-zero ohms indicates a failed thermistor.
- Check wiring continuity from the thermistor harness connector back to the control board if the thermistor tests good. Also test each wire to ground to rule out a short. Replace the harness if you find an open or shorted conductor.
- Replace the thermistor if resistance is out of range or wiring is intact but the code persists. Plug in the new sensor, secure any mounting clips, and reassemble the panels.
- Restore power and run a test cycle for at least five minutes. If F22 does not return and the dryer heats normally, the repair is complete. If the code reappears with a known-good thermistor and harness, replace the machine control board.
Parts Often Needed
| Part | Notes |
|---|---|
| Outlet thermistor (temperature sensor) | Amazon | Verify the part number against your dryer’s model and serial tag. WP8577274 fits many Whirlpool Duet models but always cross-reference. |
| Thermistor wiring harness | Amazon | Order if the connector or wires are melted, corroded, or cut. Match the harness to your exact dryer series. |
| Machine control board (main PCB) | Amazon | Required only if the thermistor and harness test good but F22 persists. Confirm the board part number from your dryer’s service sheet. |
When to Call a Pro
Call a technician if you are not comfortable working with a multimeter, if the dryer’s cabinet disassembly is unclear, or if you have replaced both the thermistor and harness but F22 still appears. Control board diagnosis requires schematic reading and may involve live voltage checks. A qualified appliance tech can also verify that the exhaust duct is not restricted (a blocked vent can sometimes cause unusual temperature readings) and can cross-check other thermal components in one visit.