The right vertical axis (Y-axis). Orientation: Horizontal lines. These lines tell you how much moisture is actually in the air (measured in grains of moisture per pound of dry air). If you trace a line straight across from the right axis, you are looking at air with a specific moisture content, regardless of its temperature.
Now, simply read the chart from that dot: how to read psychrometric chart
To the untrained eye, a psychrometric chart looks like a bowl of colorful spaghetti—a tangle of lines, curves, and numbers. But for HVAC engineers, meteorologists, and building scientists, it is the most powerful tool for understanding the invisible world of moist air. The right vertical axis (Y-axis)
