What was found
FLIGHT DEPARTED MCI WITH MEL 21-26-04A APPLIED, SKIN AIR OUTLET VALVE INOP. AFTER TAKEOFF, CREW RECEIVED AN ECAM MESSAGE: VENT SKIN VALVE FAULT. PERFORMED ECAM PROCEDURE PER OPS PROCEDURE FOUND IN MEL 21-26-04 (WHICH THE AIRPLANE IS CORRECTLY UNDER). ECAM PROCEDURE WAS UNSUCCESSFUL. FLIGHT RETURNED TO FIELD AT MCI. MAINTENANCE RESTORED SYSTEM TO NORMAL (REVERSED MEL PROCEDURE) AND ACCOMPLISHED SATISFACTORY AEVC TEST IAW AMM TASK 21-26-00-710- 001-A. NO FAULTS DISPLAYED. CLEARED MEL 21-26-04A. AIRCRAFT OK FOR CONTINUED SERVICE.