Fancy Refrigerant Words
The HVAC industry uses all sorts of fancy words to classify refrigerant. As such, there are all sorts of complicated refrigerant acronyms: HFC, HCFC, CFC. Let’s also not forget the mythical zeotropic, azeotropic, and near-azeotropic descriptors. Let’s simplify those. (Though if you want to go back to the basics first, check out this article on […]
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The Impact of Adding or Removing Water From Air
Air conditioning was about humidity control from the very start. Willis Carrier’s very first air conditioning system was all about controlling the humidity with the side effect that it also could reduce the sensible temperature. Theaters caught on that this newfangled contraption could lead to big summer numbers when they installed it to keep patrons […]
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The Sneaky Effects of Radiant Heat Transfer
If you’ve ever sat close to a bonfire on a really cold night, you may have noticed that your face starts to get really warm. The minute you put your hands up and shield your face from the light of the flame, your face cools off almost immediately. That happens because the flame is heating […]
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Mistakes in Measuring Ohms
In HVAC and electrical school, one of the first things you learn about electricity is Ohm’s law: Volts (V) = Amps (I) x Ohms (R) Pretty simple, right? Watt’s law is just as easy: Watts (P) = Volts (E) x Amps (I) With this newfound knowledge, the student walks confidently into the real world with […]
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Tips for Managing Millennials and Zoomers
Many of the “old-timers” in our trade are baby boomers; they were likely born after World War II ended and before the mid-1960s. These people grew up in a different time than today’s millennials (Gen Y) and zoomers (Gen Z). As those old-timers continue to retire, our trade needs to start attracting, recruiting, and managing […]
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Unapologetically a Technician
For years, I’ve worked with and around people who view work, problems, and goals differently than I do. I’ve often told my wife that I have an issue managing and leading administrators, salespeople, and other inside staff. Why? It’s because I just don’t communicate in a way they seem to like. It’s been 20 years […]
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Why and How to Adjust a TXV/TEV
As we discussed in an earlier podcast, a TXV maintains a specified and constant superheat at the evaporator coil outlet. It does this through a balance of forces between the bulb pressure (opening force), equalizer pressure (closing force), and spring pressure (closing force). We can actually adjust the spring pressure on some valves. But why […]
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How much PRESSURE is that Recovery Tank Designed For?
Most techs know that you shouldn’t fill a recovery tank more than 80% with liquid-based refrigerant. Many know that the WC rating stands for “water capacity.” So, you need to adjust for the density of the actual refrigerant rather than just using 80% of WC. I hope most of you know that the TW marking […]
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Something to Watch For When Replacing a Thermostat
Sometimes, you may have to replace a fancy thermostat with a simple one. It may be because the customer got fed up with all the options, or maybe the basic stat is the only thing on your truck. No matter the reason, you need to make sure the new thermostat can do the old one’s […]
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