As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, THE NR 3 FIRE WARNING CAME ON. THE CREW DECLARED AN EMERGENCY, SHUT DOWN NR 3 ENGINE AND THE WARNING LIGHT EXTINGUISHED. THE FLIGHT RETURNED TO AIRPORT AND LANDED UNEVENTFULLY. MAINTENANCE FOUND THE 13TH STAGE DUCT FROM THE PRBC AND FUEL HEAT DUCT BLOWN OUT. REMOVED AND REPLACED THE DUCT. OPS CHECKED GOOD. A/C RETURNED TO SERVICE.