What was found
CREW REPORTS CABIN CREW HAD SMOKE IN CABIN WITH ACRID SMELL AND SHORTLY AFTER A "RECIRC FAN" STATUS MSG APPEARED. CREW TURNED OFF RECIRC FAN SW AND HAD CABIN CREW TURN OFF ALL CABIN LIGHTS AND GALLEY PWR. AHM SHOWS LWR LEFT RECIRC FAN FAULT (MAINT MSG#21-24600). SMOKE AND SMELL CLEARED IN THE CABIN. REPLACED LT LOWER RECIRC FAN, FOUND CB A18 OPEN WHEN PREPPING FOR REPLACEMENT, FOUND SOOT AND BURN SMELL IN FAN. RAN PACKS AFTER, NO BURNING SMELL OR SMOKE NOTED.