When you step a certain number of blocks in front of a fan, you would immediately be extinguished if you were on fire. Any fire blocks 3 or so blocks in front of a fan would also immediately be extinguished. The idea is that it is blowing out the flames. It is the only potential use for the fan that I could think of, at least.
This could be useful for the Fire Gym as an alternate way apart from the current method of water blocks to extinguish the player after they jump into the lava pool to enter the lower level of the Gym. The fan is orange so it should look fine in there.