What was found
DURING CLIMB AFTER TAKEOFF, AT 1000 FEET, THE CABIN STARTED CLIMBING WITH THE AIRCRAFT AND A LOUD SQUEAL WAS HEARD COMING FROM THE FORWARD CABIN. THE CREW OF FLIGHT 2321 RETURNED TO DAY AND MADE AN UNEVENTFUL LANDING. PSA MAINTENANCE FOUND THE PASSENGER DOOR SEAL DAMAGED. THE SEAL WAS REMOVED AND REPLACED IAW CRJ200 AMM 52-11-10-000-803 & 400-803. THE PRESSURIZATION OPERATIONAL TEST WAS GOOD IAW CRJ 200 AMM 21-31-00-863-005. THE AIRCRAFT WAS THEN RELEASED FOR SERVICE.