What was found
ENROUTE, CREW REPORTED CABIN ALTITUDE WARNING HORN SOUNDED AS THEY ENCOUNTERED A SLOW LOSS OF CABIN PRESSURIZATION. PRESSURE LOSS WAS NOT EXPLOSIVE BUT CREW COULD NOT CNTRL PRESS. FLIGHT DESCENDED TO 10,000 FT AND CONTINUED. NO OXYGEN MASKS WERE DEPLOYED. FLIGHT LANDED WITHOUT FURTHER INCIDENT. MAINT FOUND FWD OUTFLOW VALVE FAILED IN OPEN POSITION. REPLACED VALVE IAW MM. ALSO FOUND AND REPAIRED LEAKS AT RT PACK MIX VALVE (HOT SIDE) AT FUSELAGE PEN IN PACK BAY, AFT DRAIN MAST, ALL (4) CABIN DOORS, REPLACED LEAKING PRESS REG VALVE FOR AVIONICS EQUIP COOLING AND REPLACED LT A/C MIX VALVE FOR INTERMITTENT OPS. ACCOMPLISHED SATISFACTORY OPS CK OF PRESSURE CNTRL SYS IAW MM AND SINGLE PACK. AC OK FOR SERVICE.