Open your window fully. Set the window fan horizontally in a double-hung window opening and vertically, with the left side of the fan situated at the bottom of the window opening, for a slider window.
Close the window against the fan. The bottom of the window should set against the window fan's flat top.
Pull out the extender panels on each side of the window fan to fit the fan to the window casing. This keeps any uninvited creatures from crawling through the opening on either side of the fan.
- Remove the fan and lock your window when you leave your home.