Cissell Dryer Error Code AF-2: Airflow Switch Failed to Close
AF-2 means the airflow switch did not close after the cycle started, so the control never saw proof of moving air and held the heat off. The drum may turn without heating the load. Switch the dryer off, empty the lint screen, check that the lint door closes tightly, look at the outside vent, and try one cycle.
Medium: the control holds the heat off, which protects the dryer but stops drying until airflow is proven.
What does Cissell error code AF-2 mean?
On a 120 or 170 lb Cissell with the micro control, such as the CU120L, the blower starts first and the control then waits for the airflow switch to close. The switch is a small paddle in the exhaust path, and moving air pushes it closed. If the control waits and the switch never closes, it assumes that air is not flowing and keeps the burner or heater off, then posts AF-2. This matters because heating a drum with no exhaust can overheat the cabinet. Staff see a drum that turns without heating the load. The usual cause is simple restriction, a lint screen packed full or a vent that is blocked at the outside opening. A lint door that does not seal can also pull air in the wrong place, so the paddle sees less flow than the blower is making. If the airflow is clearly good and AF-2 stays, the switch or its wiring needs testing.
Affected models and control systems
This page covers the Cissell 120 and 170 lb tumble dryers with the micro control, C-prefix models. Other Cissell controls use different codes.
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
- Display shows AF-2 shortly after the cycle starts
- Drum turns and the blower runs but there is no heat
- Clothes come out cool and damp
Possible causes
Listed in Cissell's documentation
- A blocked lint screen or exhaust duct
- Air leaks in the blower and air path
- An airflow switch that does not move
- Damaged switch wiring or a failed control input
Other likely causes — what usually sits behind error code AF-2 on this control. A technician confirms which one it is before any part is replaced.
- A vent hood outside with a flap that is stuck shut or caked with lint
- A long exhaust run with a crushed or kinked section, which starves the paddle of air
- A paddle that sticks open because of dried lint and cannot respond to normal flow
Safe checks before calling for service
- Switch the dryer off and let it settle.
- Empty the lint screen and make sure the lint door closes tightly.
- Look for blockage at the outside vent opening.
- Restore power and try one cycle. If AF-2 returns, note how soon it showed up and call us.
How a technician diagnoses error code AF-2
- Read the code and run a cycle to see how long the control waits before it posts it.
- Check airflow at the vent outlet and inspect the duct run.
- Look at the air path for leaks at the lint door and blower housing.
- Test the switch for closure while the blower runs, and check its wiring.
- Replace the switch or control only after the flow and switch tests agree.
- Duct checks go beyond the lint screen and often need a ladder and tools at the outside vent.
- The switch and its wiring are behind panels carrying line voltage.
- Running the dryer hot with poor exhaust can damage the cabinet and the load.
How error code AF-2 differs from similar codes
AF-1 means the switch is closed before the blower runs. A flashing AF means the switch toggled five or more times in one cycle.
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
Can I run the dryer with AF-2 on?
The control prevents heating, so the dryer will not dry the load. It is best to clear the cause first.
Is a blocked vent really enough to cause AF-2?
Yes. If air barely moves, the paddle does not close, and the control cannot confirm exhaust.
Will cleaning the lint screen fix it?
Often, if lint was the cause. If AF-2 returns the same day, the duct or switch needs a closer look.
Need help with Cissell error code AF-2?
A technician confirms the cause on site and gives you the price in writing before any work starts.