What was found
(CAN) PILOT REQUESTED RAPID DESCENT TO 10,000 FEET AND ADVERSION TO ALTERNATE LANDING SITE. PILOT REPORTED DOOR SEAL LEAKING AND A SLOW DEPRESSURIZATION. RUN-UP RT ENGINE AND WITH DOOR OPENED, DEPRESSED THE PLUNGER FOR THE DOOR SEAL VALVE AND ALLOWED THE SYSTEM TO PURGE OFF WATER WHICH WAS FOUND IN THE SYSTEM. AIRCRAFT TT: 2,198 HOURS.