As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PIT-ORF - FLT 1272 - DURING CRUISE AT 19,000 FEET, THE PRESSURIZATION OUTFLOW VALVE OPENED. THE VALVE WAS MANUALLY CLOSED BUT THE PASSENGER OXYGEN MASKS DEPLOYED. THE AIRCRAFT RETURNED TO THE FIELD AND LANDED WITHOUT INCIDENT. MAINTENANCE REPLACED THE PRESSURIZATION CONTROLLER, AND THE AMPLIFIER AS A PRECAUTION. THE OXYGEN MASKS WERE STOWED. (M)