As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 1 PACK VALVE CLOSES IN FLIGHT. REMOVED AND REPLACED THE NR 1 A/C PACK VALVE IAW AMM 21-51-01. PERFORMED AN OPS CHECK IAW AMM 21-60-00, OPS CHECKED FAILED DUE TO THE NR 1 PACK OVERHEAT. FOUND THE NR 1 A/C PACK ACM DUCT DETACHED. SECURED IAW AMM 21-20-00/21-51-00. OPS CHECKED GOOD.