What was found
DURING FLIGHT FROM SJU, COULD ONLY PRESSURIZE AIRCRAFT AT TO 5.0PSI DIFFERENTIAL, WITH ALL T.C.'S RUNNING AND OUTFLOW CLOSED. CABIN CONTINUED TO CLIMB TO F.L.16.0 AFTER LEVEL OFF AT F.L. 29.0. AIRCRAFT DIVERTED TO MIA WITHOUT INCIDENT. FOUND CONNECTOR CLAMP AT NR 1 AND NR 2 T/C DELIVERY DUCT TO MIXING VALVE DISCONNECTED. RECONNECTED CONNECTORS, PRESSURIZED AIRCRAFT, OPS CHECKED NORMAL, 8PSI DIFFERENTIAL.