As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, COCKPIT DUCT HOT AND CABIN DUCT HOT CAUTIONS ILLUMINATED. UNABLE TO CONTROL IN AUTO OR MANUAL, AIRFLOW WEAK. RETURNEN TO FIELD. LANDING UNEVENTFUL. REMOVED FROM SERVICE. FIM TROUBLESHOOTING OF LOW AIR FLOW FROM CABIN IAW 21-60-00-810-882, NO DEFECTS OR FAULTS NOTED, INSPECTION AND REPLACEMENT OF DISTRIBUTION DAMPER ROTARY ACTUATOR AS A PRECAUTION IAW 21-22-06-000/400-802. OPS TESTED GOOD. OBSERVED 20 DEGREE COCKPIT & CABIN DUCT DECREASE WITH ENGINES RUNNING. ACFT OK FOR SERVICE.