As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DUB FLT 798 EN ROUTE PHL TO AMS. THE CABIN PRESSURE ALTITUDE BEGAN TO CLIMB. THE CREW WAS ABLE TO STOP THE PRESSURE CLIMB AT 12,000 FEET. THE FLIGHT DIVERTED TO DUB AND LANDED WITHOUT FURTHER INCIDENT. REMOVED AND REPLACED THE RT PACK HEAT EXCHANGER ASSEMBLY. THE SECONDARY HEAT EXCHANGER WAS FOUND RUPTURED. THE HEAT EXCHANGER WAS CORED AND OVERHAULED.