Cissell Dryer Error Code AF Flashing: Airflow Switch Cycling
A flashing AF means the airflow switch opened and closed five or more times during a running cycle, which points to uneven airflow or a switch that is not holding. The control stops the cycle. Let the dryer cool, clean the lint screen, wipe the door seals, check the outside vent, then run a lighter load.
Medium: the cycle stops but the control is doing its job; the cause needs finding before it repeats.
What does Cissell error code AF mean?
On a 120 or 170 lb Cissell, such as the CT170N, air should flow evenly while the dryer runs, so the airflow switch should close once and stay closed. The micro control counts the times the switch changes state during a cycle. When it counts five or more, it decides the airflow is not steady and stops the cycle, leaving AF flashing on the display. Steady AF in the same family is a closed-at-start or never-closed problem. A flashing AF is about instability. That can be an exhaust path that surges because lint is partially blocking it, a heavy wet load that restricts air, leaks at the blower and drum seal, or a switch whose pivot or wiring jumps with vibration. The cycle ends partway, and clothes may still be damp. Watching how soon it appears in the cycle, and whether it depends on the load, helps a technician tell airflow from the switch.
Affected models and control systems
This page covers the Cissell 120 and 170 lb tumble dryers with the micro control, C-prefix models. A flashing display is different from a steady AF code.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- AF flashes on the display and the cycle stops partway
- The dryer may click or surge before stopping
- Clothes are damp at the stop and heavy loads make it more likely
Possible causes
Listed in Cissell's documentation
- Uneven airflow from lint or duct problems
- An airflow switch that moves unsteadily or has loose wiring
- Heavy loads that choke air movement
- A worn blower or drum seal that leaks air
Other likely causes — what usually sits behind error code AF on this control. A technician confirms which one it is before any part is replaced.
- A lint screen that is clean but has a torn edge that lets lint reach the paddle area
- An exhaust hood that opens and closes in the wind, which makes pressure change in the duct
- A switch connector that rattles when the drum is loaded and spinning
Safe checks before calling for service
- Shut the dryer off and allow it to cool before you look at anything.
- Clean the lint screen thoroughly and wipe the door seals.
- Check the vent opening outside for lint, nests or a bent cover.
- Restore power, run a lighter load, and call us if AF flashes again. Note what the load size was.
How a technician diagnoses error code AF
- Read the code and ask about load size and when in the cycle it stopped.
- Check airflow at the vent outlet with the dryer running and watch for surges.
- Inspect the blower housing, drum seals and door gasket for leaks.
- Watch the airflow switch during a cycle and check its wiring for movement.
- Replace the switch, or correct the duct, only after the test shows the cause.
- Unsteady airflow is harder to trace than a plain blockage, and it needs the dryer running with airflow measured at the outlet.
- The airflow switch and blower housing are inside the cabinet, near line-voltage wiring.
- Repeated stops leave loads damp and burn extra gas or power each time.
How error code AF differs from similar codes
A steady AF-1 or AF-2 describes a switch that is stuck or never closes. A flashing AF means it keeps changing state.
Technical reference
- Document
- Tumble Dryers 120/170 lb Troubleshooting TMB1268C, Part No. 70399901R2, Dec 2016 (pp.53, 65)
- Edition
- Part No. 70399901R2, December 2016; models through serial no. 0907000048
- Models / control
- 120/170 lb tumble dryers micro control (C-prefix models)
- Section
- Hybrid Timer Control Troubleshooting - 31. Error Codes, printed p. 53 (PDF p. 55); On Premise Micro Control (RM) Troubleshooting - 36. Error Codes, printed p. 65 (PDF p. 67)
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Cissell dryer error codes
Why does AF flash instead of staying on?
Flashing means the switch opened and closed five or more times in one cycle, not that it is stuck.
Will a lighter load help?
It can, if the heavy load was choking the air. If it still happens, the duct or switch needs a look.
Can I restart the dryer after AF flashes?
Yes, once it has cooled and the lint is cleaned. If it flashes again, stop and call.
Need help with Cissell error code AF?
A technician confirms the cause on site and gives you the price in writing before any work starts.