Fan stack and Speed reducer:

Fan - A fan is a device used to induce air flow by the cooling tower.

Fan deck - The fan deck is a horizontal surface enclosing the top of the cooling tower above the plenum which serves as a working platform for inspection and manages.

Fan stack - The fan stack is a cylinder enclosing the fan, commonly along with an eased inlet and an expanding discharge for increased fan effectiveness.

Fill - The fill is wood, PVC, metal, or an instead material which gives extended water surface exposure for evaporative heat transfer.

Intake louvers - The intake louvers are an arrangement of horizontal blades at the air inlets which avoid escape of falling water although permitting the entry of air.

Makeup valve - The makeup valve is a valve which introduces fresh water inside the collection basin to manage the desired collecting basin water level.

Overflow - The overflow is a drain which avoids the collecting basin from overflowing.

Partition - The partition is a baffle inside a multicell cooling tower which is used to avoid air and/or water flow among adjacent cells.

Plenum - The plenum is the internal cooling tower area among the drift eliminators and the fans.

Speed reducer - A speed reducer is a right-angle gear box which transmits power to the fan although reducing the driver speed to which needed for optimal fans performance.