What was found
AIRCRAFT WAS GROUNDED: BURNING SMELL EVIDENT AFTER T/O SMELLED LIKE OVEN,BUT NONE WERE ON. LASTED ABOUT 3-5 MINUTES. FLIGHT ATTENDANTS IN AFT GALLEY SAID SMELL WAS VERY STRONG TO THEM., NOT AS MUCH IN FORWARD GALLEY. FLIGHT ATTENDANTS REPORTED THAT AFT CHILLER WAS ON DURING TAKEOFF,BUT WAS NOTED TO BE "OFF" AFTER THIS EVENT. NO SMOKE. ALL CIRCUIT BREAKERS IN. NO OTHER EVIDENCE OF BURNING. MAINTENANCE DETERMINED SOURCE OF ODOR TO BE THE APU. (OPEN)