As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ACFT ARRIVED WITH 2 SNAGS RELATED TO AIR CONDITIONNING. CABIN TEMP HARD TO COOL DOWN AND LOW FLOW PLUS BOTH PACKS SURGING ON THE GROUND. REF W/O 1089584. DURING TROUBLESHOOTING, FOUND NR 1 PACK OUTLET DUCT RUPTURED. MISSING AREA APPROX 6" X 3". DUCT WAS REPLACED AND SYS CHECKED SERVICEABLE.