What was found
CREW REPORTED SMELL ABNORMAL BEFORE PUSHBACK,AMT ADVISED CREW TURN ON PACKS,LESS THAN 2 MINS SMOKE AND ASH COMING FROM AIRCON OUTLET,WE FOUND STATUS MESSAGE RECIRC FAN,GROUND CREW REPORTED HEAVY SMOKE COMING FROM UPPER FUSELAGE AND MDC.WE REPORTED TO CREW AND CREW EVACUATED AS PER PROCEDURE. REF AMM 21-25-08-4 R/R'ED BOTH RH RECIRCULATION AIR FILTERS AND REF AMM21-25-07-4, R/R'ED RH RECIRCULATION FAN FAN AND OPS TEST SATIS.