Uploaded April 2026 | Updated September 2026, 2 weeks ago
Ever stared at a psychrometrics chart and felt your brain short-circuit? You're not alone. In this episode, we break down the magic behind the most powerful tool in HVAC — and why one line on that chart secretly rules everything you do on every service call.
We trace the history of psychrometrics from wet-bulb thermometers to Willis Carrier's legendary 1911 paper, then walk through the 3D relationships between dry bulb temperature, humidity ratio, enthalpy, and the dew point — that magic line where vapor becomes liquid and surfaces start sweating.
Whether you're troubleshooting a clammy house, a dripping air handler, or trying to understand why your supply air leaves at 90% RH, this episode connects the dots between the math and the real world.
Apps do the math. The chart gives you the soul behind it.
Read all the tech tips, take the quizzes, and find our handy calculators at hvacrschool.com or the HVAC School Mobile App on the Google Play Store (hvacrschool.com/play-store) or App Store (hvacrschool.com/app-store).
Ever stared at a psychrometrics chart and felt your brain short-circuit? You're not alone. In this episode, we break down the magic behind the most powerful tool in HVAC — and why one line on that chart secretly rules everything you do on every service call.
We trace the history of psychrometrics from wet-bulb thermometers to Willis Carrier's legendary 1911 paper, then walk through the 3D relationships between dry bulb temperature, humidity ratio, enthalpy, and the dew point — that magic line where vapor becomes liquid and surfaces start sweating.
Whether you're troubleshooting a clammy house, a dripping air handler, or trying to understand why your supply air leaves at 90% RH, this episode connects the dots between the math and the real world.
Apps do the math. The chart gives you the soul behind it.
Read all the tech tips, take the quizzes, and find our handy calculators at hvacrschool.com or the HVAC School Mobile App on the Google Play Store (hvacrschool.com/play-store) or App Store (hvacrschool.com/app-store).
