When AF comes up on your dryer, it indicates an air flow issue. We would recomend checking your venting for kinks and or bends. Taking off the venting to check for any lint build up. You can also verify that your lint filter is clean and clear. If you have checked and verified that these are ok, We would recommend having a local certified technician in your area properly diagnose and repair the issue you are experiencing. Please call (800)344-1274 Monday-Friday, 8:00 AM to 8:00 PM EST to schedule a service appointment with a local certified technician.