What was found
AIR CONDITIONING PACK WOULD NOT MAINTAIN THE CABIN AT FLIGHT LEVEL 20 THOUSAND FEET. REMOVED AND REPLACED PRESSURE REGULATOR VALVE.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
AIR CONDITIONING PACK WOULD NOT MAINTAIN THE CABIN AT FLIGHT LEVEL 20 THOUSAND FEET. REMOVED AND REPLACED PRESSURE REGULATOR VALVE.