As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SHIP 3212 DURING CRUISE FLT AT 340 CABIN ALTITUDE CLIMBED TO A MAX OF 9000 ' AND DELTA P DROPPED TO 6.1 . DECENDED TO FL 260. CABIN REPRESSURIZED TO 3800' AND DELTA P 7.9. APPROX. 1 HOUR LATER CABIN UNCONTROLLED CLIMB AGAIN, DECENDED TO 15,000' AND CABIN ALT STABILIZED. CORRECTIVE ACTION: REPLACED #1 ENG THERMOSTAT 10HA1 SOLENOID AS PER A320 AMM 36-11- 55. REPLACED NBR 1 PRV VALVE PER A320 AMM 36-11. OPS CK GOOD. (7439096)