As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PHL - FL1638, AIRCRAFT RETURNED TO FIELD AT PHL DUE TO LOUD NOISE FROM AFT RIGHT SERVICE DOOR AND NOT BEING ABLE TO PRESSURIZE. FLIGHT LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE CLEANED FOREIGN MATERIAL FROM AFT RIGHT SERVICE DOOR TRIM AND PERFORMED OPERATIONAL CHECK OF THE OUTFLOW VALVE PER MM. ALL SYSTEMS CHECK NORMAL. (M)