What was found
WHILE CLIMBING TO ALTITUDE FL210 THE ACFT LOST ITS PRESSURIZATION, CARRIED OUT QRH PROCEDURE AND RETURNED TO STATION. THE CREW DECLARED AND EMERGENCY AND WAS MET BY EMERGENCY VEHICLES ON ARRIVAL. THE FLIGHT WAS BELIEVED TO BE NOT OVERWEIGHT WHEN IT LANDED. PRESSURIZATION LOSS WAS CAUSED BY BLEED 1 LEAK EICAS CAUTION (WHILE OPPOSITE SIDE WAS ON MEL) T/S IAW 36-21-00-810-803-A RESULTED WITH A TRANSIENT CONDITION. AN APU LEAK CK PERFORMED SHOWED NO DUCT LEAKS. ODS CONNECTORS IN THE NR 1 PYLON WERE CKD WITH NO FAULTS FOUND. AMS CONTROLLER IN COMMAND AT TIME OF SNAG (AT SPDA NR 2 SLOT 18) WAS REPLACED. SYS CKS SERVICEABLE.