Erin,
Thank you for your purchase of Bosch downdraft and oven. Sorry to learn of your installation issue. All Bosch downdraft vents require the purchase of an accessory blower. Bosch has three blowers available for different application needs: Internal blower which mounts to the downdraft vent inside the cabinet, an in-line blower which mounts between the vent and the exterior of the home, or a remote blower which mounts outside on the roof or exterior wall.