What was found
FLT 1117, SYR-FLL, DIVERTED TO IAD. DURING CRUISE CABIN ALT STARTED CLIMBING UP TO 8200, TRIED MANUAL CONTROL NO RESPONSE. STARTED DESCENT INTO IAD CABIN KEPT CLIMBING TO 9800. THE DIFF MAX WAS 7.0-7.7 AFTER LANDING MAN OUTFLOW VALVE CONTROL WORKED. AUTO PRESS NEVER WORKED AFTER MULTIPLE ATTEMPT TO RESET. PERFORMED GVI OF RAM AIR INLET DUCTS IAW 21-25-05, NO DEFECTS NOTED. PERFORMED PACK OUTLET DUCT GVI IAW 21-51-21, NO DEFECTS NOTED. PERFORMED OPS CHECK OF COOLING PACKS. FOUND NR 2 PACK DISCHARGE AIR ESCAPING THROUGH RAM AIR CHECK VALVE AND FREEZING NR 2 WATER SPRAY NOZZLE. PERFORMED EMERGENCY RAM AIR CHECK VALVE OPERATIONAL. CHECK OPS TEST FAIL IAW AMM 21-25-03-710. FOUND FLAPPER HOLD OPEN ROD MISSING. PERFORMED GVI OF DUAL HEAT EXCHANGER NR 2 IAW AMM 21-51-04-210. NO CONTAMINANTS OR DEFECTS NOTED. REMOVED AND REPLACED EMERGENCY RAM AIR CHECK VALVE IAW 21-25-03-401. OPS CHECK OK, DEPRESSURIZATION CHK OK IAW AMM 05-50-08.