As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMBOUT FROM YOW THE AIRCRAFT FAILED TO PRESSURIZE. THE CREW OF FLIGHT 2269 CONTINUED TO DESTINATION (PHL) UNPRESSURIZED. PSA MAINTENANCE CLEANED THE PRIMARY OUTFLOW VALVE. THE SYSTEM OPERATIONALLY CHECKED GOOD IAW CRJ 200 AMM 21-31-00-710-802. THE AIRCRAFT WAS THEN RELEASED FOR SERVICE.