What was found
(CAN) DURING A ROUTINE FLIGHT, THE CREW NOTED THE THE CABIN PRESSURE WAS RAPIDLY INCREASING, THE CREW IMMEDIATELY DEPLOYED OXYGEN, INITIATED A DESCENT, DEPRESSURIZED THE CABIN AND DIVERTED TO BASE (WHERE PRIMARY MAINTENANCE IS ADMINISTERED). MAINTENANCE PREFORMED A GROUND RUN AND VERIFIED THAT THE RT FLOW PACK HAD FAILED, THE FLOW PACK WAS REMOVED AND REPLACED WITH A OVERHAULED UNIT AND THE AIRCRAFT WAS REALEASE FOR A TEST FLIGHT.