PILOT LIGHT ON. TURNED UP THERMOSTAT TO CALL FOR HEAT. BURNERS WENT ON. FAN SOUNDED LIKE IT IS GOING TO KICK IN "BUT" THEN EVERYTHING SHUT OFF. TRIED IT AGAIN, SAME RESULT. PREVIOUS TO THIS, I NOTICED A SMELL OF MELTING WAX SMELL COMING FROM THE FURNACE CABINET. FAN MOTOR PROBLEM ? FAN BELT? WHERE IS THE MOTOR AND BELT LOCATED IN THIS MODEL? HOW TO I CHANGE IT OUT? MS.ILONA SMITH