As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE CABIN STARTED TO CLIMB WITH A PRESSURIZATION FLOW LIGHT AFTER MANUALLY CLOSING OUTFLOW VLV CABIN WAS STILL CLIMBING. BOTH FLOW GOUGES SHOWED AIR TO THE PACKS AT 10000 CABIN STARTED TO DESCEND. CABIN ALTITUDE NEVER EXCEEDED LIMITS. FLIGHT LANDED WITHOUT INCIDENT. FOUND DUCT LEAK AT FLANGE OF RT PACK WATER SEPARATOR. REPLACED DUCT & BOTH WATER SEPARATORS. SYS GND CHECKED NORMAL OPERATION CLOSED.