As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A/C WOULD NOT MAINTAIN CABIN ALT ON CLIMBOUT. WOULD NOT MAINTAIN PSI IN AUTO-STANDBY OR MANUAL OR ANY BLEED. WHILE TROUBLSHOOTING ITEM FOUND THAT THE RT PACK WAS NOT OPERATING WHEN SELECTED ON, REMOVED AND REPLACED THE RT AIR SHUTOFF VALVE IN REF TO 727-200 AMM 21-55-071-4. PERFORMED OPS CHECK OF THE RT PACK AND PACK OPERATED NORMALLY ALONG WITH THE RT AIR MIX VALVE. PERFORMED A DECAY CHECK PER 727 JRH CHAPT 7 PG 7-51 TO 7-54 DECAY CHECK PASSED, A/C IS OK FOR CONTINUE SERVICE.