Unconformed Free Chapters
Unconformed Signup * indicates required Email Address * Click HERE for the FPEA Presentation Expanding Your Child's Career Opportunities Here is two free chapters of Unconformed Chapter 1: Papa and Wrecked Planes I’ve got this mental image of my grandfather engraved in my mind's eye. He’s in his office at his aircraft hangar, leaning back […]
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Does Mass or Volume Move Heat?
I once heard someone say, and have since repeated many times that BTU's ride on the back of Cubic Feet of Air or CFM. As I've learned more I've come to the conclusion that the weight or mass of the air passing over the evaporator coil is far more important to understand both in terms […]
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Why is the Air Dry at Altitude?
So, here's the thing. When I was a kid, I got to go skiing in the Rockies a few times. Sounds great, right? Well, yeah, the skiing was fantastic, but the dry air at those higher elevations? the dryness and the lack of oxygen combined felt like breathing vapor beef jerky. Cut to me getting […]
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The Strange Behavior of Moisture in Stuff
Water is weird and water vapor is even weirder – before we dive down this rabbit hole lets define some terms To better understand the behavior of moisture in materials, we need to first define some essential terms and concepts: Relative Humidity (RH): The ratio of the amount of water vapor in the air to […]
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Impacts of Decreasing Evaporator Airflow
Airflow, airflow, airflow… When we set up and commission comfort cooling and heating systems, we need to pay more attention to airflow before worrying about the fancy controls or the refrigerant circuit. One way to do that is by checking out Bill Spohn's Airflow 101 webinar on ESCO Group's learning network, which you can access […]
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Gas Law Concepts for HVAC/R
If you went to school and learned the “gas laws” early on, you probably thought it seemed LAME. Then, later, things like mass flow rates, airflow conversions, and compression ratios seemed HARD. Well… It's because HVAC is hard if you don't understand the concepts behind the gas laws, even if you never learn to do […]
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Condensate Drain Codes & Best Practices
It should be stated and restated that codes and code enforcement vary from location to location within the US. The IMC (International Mechanical Code) is one of the most widely utilized and referenced. The 2015 version of the IMC section 307 is what I will be referring to in this article. Condensate Disposal  The code […]
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Air Barrier vs. Vapor Barrier vs. Insulation
Think of it like this: It's a cold, wet, windy day. You can take an umbrella to protect you from the water alone, but that won't deal with the cold (temperature) or the wind (air convection). You can add in a light windbreaker, which will help keep the wind (convection) off. But if you also […]
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Why Many Techs Confuse Overload, Short, & Ground Fault
The point of this article is to give you a full understanding of the role fuses, overloads, and circuit breakers play in the protection of HVAC/R equipment. If you skim-read or jump to conclusions, you will be tempted to argue. Be patient; if you want to understand, you will need to read all the way […]
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