A heat exchanger including a housing having a base and defining an interior. A plurality of coils are located in the interior of the housing and are arranged to extend upwardly from the base to define a coil depth. A blower is adapted to move air through the plurality of coils in a direction of the coil depth. A water distribution system is preferably located around a circumferential periphery of the plurality of coils to spray water on an outer surface of the plurality of coils along substantially the entire coil depth thereof. At least one air inlet opening is located in the housing to allow airflow across the plurality of coils. Additional embodiments of improved heat exchangers are disclosed herein.