limit the scope of embodiments of the invention skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention fig7 and 15 illustrate a ventilation assembly 10 according to one embodiment of the invention some embodiments of the ventilation assembly 10 can include several components and devices that can perform various functions in some embodiments the ventilation assembly can include a main housing 25 which can house the various components and devices of the ventilation assembly 10 in some embodiments the ventilation assembly 10 generally can include a upgrade cartridge assembly 20 substantially housed within the main housing 25 and positioned within the main housing 25 aided by a fan cartridge locating rib 80 and coupled to the main housing with a fan cartridge snap retention feature 85 in some embodiments the upgrade cartridge assembly 20 generally can include a motor 30 such as a permanent split capacitor motor 30 and a motor capacitor 35 some embodiments provide a upgrade cartridge assembly 20 that can also include a scroll 40 and a blower wheel 50 positioned substantially within the scroll 40 and mechanically coupled to the motor 30 furthermore in some embodiments a duct connector assembly 270 can be coupled to the ventilation assembly 10 the duct connector assembly 270 can include a moveable damper flap 280 coupled with a ventilation orifice 272 in some embodiments the damper flap 280 can.