Abstract: An air venting apparatus for use with air discharging blowers, fans, including an air outlet duct and flap valve which pivots at top of a hood. The flap valve closes the outlet end of the duct by gravity. One leaf spring clip which acts on the valve flap to retain the same in the closed position. The spring clip maintains enough force to retain the valve flap in the closed position against pressure differentials developed by the outside wind, but is fabricated to allow opening of the valve flap against pressure differentials developed by the air discharge blower (fan).