What was found
EN ROUTE TO CLT, 40 MILES EAST OF FLO THE CREW SMELLED A STRONG BURNING SMELL. FLIGHT ATTENDANT REPORTED NO SMELL OR SMOKE. THE CREW TURN ON COCKPIT LIGHTS AND COULD SEE A SMALL AMOUNT OF SMOKE. DECLARED AND EMERGENCY AND DIVERTED TO FLO. DESENDING TO 10K FEET, CREW OPENED THE FORWARD OUT FLOW VALVE AND THE SMOKE AND SMELL WENT AWAY. CANCELLED THE EMERGENCY AND CONTINUED ONTO CLT. ARRIVED IN CLT WITH NO PROBLEMS. MAINT FOUND CIRCUIT BREAKER POPPED, UPON TROUBLESHOOTING FOUND COCKPIT ZONE TEMP SENSOR (FAN) INOP. REMOVED AND REPLACED ZONE TEMP SENSOR IAW 21-60-45. OPS CHECK GOOD.