AN AIRBUS 319 WAS DISPATCHED WITH CONNECTORS ON OUTFLOW VALVES SWAPPED TO ALLOW OP OF #1 PRESSURIZATION SYS. ACFT RETURNED TO THE FIELD WITH LOSS OF CABIN PRESSURE.

Narrative

I RECEIVED A CALL AND REQUEST FROM ZZZ MAINT REQUESTING PERMISSION TO SWAP THE CABIN OUTFLOW VALVE AUTOMOTOR CONNECTORS FROM THE #1 TO THE #2 AS LCL MAINT HAD CONFIRMED THE FAULT WITH THE #1 AUTOMOTOR WITH NO MEL RELIEF FOR THE #1 AUTOMOTOR. AFTER INSURING THAT ZZZ HAD INDEED CONFIRMED THE FAILURE AND THE SWAPPING OVER THE CONNECTORS FROM THE #1 AUTOMOTOR TO THE #2 AUTOMOTOR REQUIRED NO DISASSEMBLY; I INSTRUCTED ZZZ TO SWAP THE CONNECTORS AND RE-TEST THE SYS TO INSURE NO FAULTS ON THE #1 SYS AND TO DEFER THE #2 AUTOMOTOR INOP PER MEL. 30 MINS INTO FLT; THE ACFT RETURNED TO ZZZ DUE TO A CABIN PRESSURIZATION SYS #1 AND #2 FAULT (FAILURE); AFTER MAINT INVESTIGATED THE OUTFLOW VALVE WAS REPLACED AND AS OF THE WRITING OF THIS RPT NO ADDITIONAL FAILURES HAVE OCCURRED (5 LEGS). DOWNLOADED DATA SUPPORTS THE ONLY FAILURE MESSAGE PRIOR TO DISPATCH (SWAPPING THE CONNECTORS) WAS THE #1 AUTOMOTOR AND AT THE TIME OF THE AIR TURN BACK THE ONLY FAILURE WAS THE #1 AUTOMOTOR AGAIN (THIS WAS ACTUALLY THE #2 AUTOMOTOR AS THE CONNECTS WERE SWAPPED ON THE OUTFLOW VALVE). THE COMPANY FLT MANUAL DOES CONTAIN PROCS FOR BOTH #1 AND #2 SYS INOP AND AT THE TIME OF THE AIR TURN BACK NO RPTS OF PROBS WITH THE MANUAL PRESSURIZATION SYS WERE RPTED.