What was found
CREW REPORT: ELEC BURNING SMELL 13000 & 20000 ALT. *S/D* FOUND EICAS MESSAGE AFT EQ EXH FAN 1, REPLACED FAN. ACP HIGH POWER RUN AND CHECKED ECS SYSTEM FOR ODOR, FOUND NO ODOR FROM PACKS. COULD NOT DUPLICATE ANY TYPE OF BURNING SMELL THROUGHOUT THE AIRCRAFT. INBOUND CREW REPORTED NO EICAS MESSAGES RELATED TO EQUIPMENT COOLING OR FAN STATUS MESSAGES. ACCOMPLISHED TEST FLIGHT OF ACFT. TEST FLOWN 1.5 HRS FOR BURNING ODOR. NO ODOR DETECTED. OPS NORMAL.