Last time we talked about the impact that the wet bulb temperature has on cooling tower performance. In summary, it’s harder to evaporate water into air that’s already wet. (I.e. The higher the wet bulb, the harder a cooling tower has to work to evaporate enough water to maintain set points.) In this blog, we’re going to define what those set points are, how cooling towers are rated, and finally how these factors impact the cooling tower size and operation for a given application.