ACR LGT MADE A TKOF WITH 1 PACK INOP THEN HAD TO DIVERT TO ALTERNATE WHEN CABIN PRESSURE COULD NOT BE MAINTAINED.

Narrative

AT NEWARK AND ON THE TAXIWAY JUST PRIOR TO TKOF; THE R PACK TRIP OFF LIGHT ILLUMINATED. AFTER STABILIZING THE PROBLEM; I INFORMED THE CAPT; AND WE PERFORMED THE 'PACK TRIP OFF LIGHT ON' ABNORMAL CHKLIST. THE LIGHT REMAINED ILLUMINATED AFTER THE RESET PROC. THE PACK TEMP GAUGE INDICATED IN NORMAL RANGE. THE CAPT'S DECISION WAS TO CONTINUE. AFTER TKOF THE LIGHT REMAINED ON. THE CABIN CLBED NORMALLY UNTIL FL240 WHERE IT READ 8000 FT CABIN ALT. HOWEVER; THE CABIN VERY SLOWLY CONTINUED TO CLB. WE IMMEDIATELY REQUESTED DSCNT TO LOWER ALT. WE THEN INFORMED THE FLT ATTENDANTS OF THE PROBLEM AND WHAT TO EXPECT AND IMMEDIATELY PERFORMED THE 'RAPID DECOMPRESSION/EMER DSCNT' EMER CHKLIST. THE CABIN STILL CONTINUED TO CLB. THE PAX OXYGEN MASKS WERE DEPLOYED AUTOMATICALLY AT 14000 FT CABIN ALT. MEANWHILE WE ARE STILL DSNDING THE ACFT UNTIL BELOW 10000 FT. I HAD BEEN IN CONTACT WITH MAINT AND DISPATCH AND WE WERE REDISPATCHED TWICE -- ONCE TO FLL AT LOWER ALT; AND AGAIN TO WASHINGTON NATL AFTER REALIZING THAT THE SINGLE REMAINING (L) PACK WAS UNABLE TO MAINTAIN CABIN PRESSURE. WE WERE HANDLED NORMALLY BY ATC AND PROCEEDED TO THE NEW DEST OF WASHINGTON NATL ARPT WHERE NORMAL APCH AND LNDG WAS MADE.