A fan stack is a type of ventilation system used to cool and circulate air in an enclosed space. It consists of multiple fans that are stacked on top of each other, allowing for greater air circulation and ventilation. The fan stack is usually placed in a room or other enclosed space, such as a server room, to ensure that the air remains cool and fresh. The fan stack is designed to be efficient and cost-effective, as it requires minimal energy to operate. It is also designed to be quiet, so as not to disrupt the environment. The fan stack is a great way to ensure that the air in an enclosed space is kept cool and fresh, while also being energy-efficient and cost-effective.