Abstract: Embodiments of the current disclosure include air pretreatment devices suitable for pretreatment of air received by air handler units. The air pretreatment devices can include an air intake configured to capture the outside air. A cooling coil system can process changes in the dry bulb and dew point temperatures of the captured outside air. The pretreated air can then be passed via an air outtake to the air handler. The cooling coil system can be coupled to at least a chilled water intake and a chilled water return line. Finally, a single water valve control unit located on either the chilled water intake or chilled water return line can be adjusted to direct a change in the dry bulb temperature and dew point temperature within the cooling coil system.