As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CREW REPORTED A PACK NR 1-2 OVERLOAD AFTER TAKEOFF. PACK NR 1 WOULD NOT RESET. ACFT WOULD NOT PRESSURIZE. EMERGENCY DECLARED, RETURN TO DEPARTURE. THE ACFT LANDED WITHOUT INCIDENT. THE ACFT WAS REMOVED FROM SERVICE. R & R THE NR 2 PACK PRIMARY INLET DUCT IAW AMM 36-11-09, OPS CHECK GOOD. NO DEFECTS NOTED AT THIS TIME. THE ACFT WAS RETURNED TO SERVICE.