the heat actually vibrates the blades of the fans at a special frequency that allows it to communicate with the undead.

using a special set of mircoscopic engravings on the back of every odd numbered blade, it communicates with the vengeful spirits and asks for a man named 'josh'.

once the fan hits 100°c, and josh is successfully conjured, he utilizes his insanely strong arms to push the fan in a counter-clockwise direction.

upon the cooling of the fan, josh relieved of his duties, and sent to the break room. another spirit is premoted to a 'josh' to take his place.