As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB DELTA P RISING WAS NOTED, BUT CABIN ALT WAS NOT RISING WHEN LEVELED AFTER TROUBLESHOOTING CABIN ALT DECREASED DELTA P INCREASED. PERFORMED CABIN PRESSURE TEST IN REFERENCE TO AMM 05-53-00-780-003-A AFTER REPLACEMENT OF SKIN AIR INLET VALVE REF LP501359 ITEM #3 TEST RESULTS GOOD, AC OK FOR SERVICE AT THIS TIME.