How To Use A Psychrometric Chart Review

"Exactly. You’ve just found the state of the air in the lobby. That single dot represents all the invisible water vapor currently torturing our guests."

"To get from your lobby dot to this new cool dot, we have to do two things," Elena explained, drawing an L-shape. "First, we move horizontally left to cool the air. That is Sensible Cooling —changing the temperature. But we can't stop there." how to use a psychrometric chart

"Right. That’s a lot of moisture. If we cool this air down without removing water, it's going to hit 100% humidity fast, and then we’ll have rain indoors." "Exactly

"Good. So the air is halfway saturated. But why does it feel so gross? Let's check the ." She pointed to the vertical axis on the far right. "Those horizontal lines measure grains of moisture per pound of dry air." "First, we move horizontally left to cool the air

F . Penn State Extension +1 Common HVAC Processes on the Chart The chart also allows you to visualize how air changes as it moves through a system: Sensible Heating/Cooling: Moving horizontally (Right = Heating, Left = Cooling) changes temperature without changing moisture content. Humidifying/Dehumidifying: Moving vertically (Up = Humidifying, Down = Dehumidifying) changes moisture without changing dry bulb temperature. Evaporative Cooling: Moving along a constant wet bulb line (up-left) as water evaporates into the air. Rotronic.com +2 For more detailed technical data, refer to professional resources like the ASHRAE Fundamentals of Psychrometrics or use software like the