As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING IN-SERVICE REPAIRS, THE OPERATOR HAS NOTICED THAT THE RECIRCULATION DUCTS WITH THE RECIRCULATION FAN CYCLING ON/OFF, MIGHT BE CAUSING FOULING WITH ADJACENT SYSTEMS. A REVIEW OF THE PRODUCTION LINE SHOWS THAT THE DUCT IS ALREADY FOULING WITH ELECTRICAL CABLES, FUEL LINES AND STRUCTURE.