This depends on the type of fan you possess. Surely the best place to keep a table fan is in an isolated area near an electrical point where it can be plugged in. There should be no obstructions in the air pathway it provides. Otherwise, it will prove fruitless. A wall-mounted fan should be on the wall opposite a large open window without any air obstacles in its way. A box fan can be placed inside a window as they are built to withstand any weather condition like rain or sun. Fans can even be paired with a bucket or bowl of ice to cool the room. In this scenario, you've got cold wind on the cards.