As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 43 JFK-MCO, AIR RETURN TO JFK DUE TO AIRCRAFT UNABLE TO PRESSURIZE WITH VENT SKIN VALVE AND A/C BLOWER FAULT. TECHNICIAN REMOVED AND REPLACED SKIN AIR OUTLET VALVE (22HQ) IAW AMM CH 21-26-53 & ACTIVATED THE SKIN EXCHANGER ISOLATION VALVE (24HQ). PERFORMED OPS CHECK OF THE VENTILATION SYSTEM FOUND OK.