Psychrometric Chart: Tutorial

Find 85° on the bottom axis (horizontal). Follow the vertical line straight up.

Where those two lines meet is the current state of your air. Congratulations, you’ve plotted your first point. The 3 Most Useful Things You Can Do Now Now that you have your point (85°F & 60% RH), let’s read the answers. psychrometric chart tutorial

The Psychrometric Chart Explained: Your No-Nonsense Guide to HVAC’s Most Powerful Tool Find 85° on the bottom axis (horizontal)

Find the 60% RH curve (it looks like a line bowing to the right). Follow that curve until it crosses the vertical 85° line. Congratulations, you’ve plotted your first point

Stop squinting at all those curved lines. This tutorial breaks down the psychrometric chart into 5 easy steps—showing you exactly how to find dew point, mixed air, and cooling loads. Introduction: Why You Can’t Ignore This Weird Chart If you’ve ever looked at a psychrometric chart and felt your eyes glaze over, you’re not alone. It looks like a spider web of lines, numbers, and curves.

(Link to PDF download) Pro Tip for your blog: Include an actual image of a psych chart with the 5 key lines circled in different colors (red for dry bulb, blue for dew point, green for wet bulb). That visual anchor doubles retention.

But here’s the truth: It tells you everything about a parcel of air—how hot it is, how wet it is, and how much energy it holds.