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Tech Tips:

Preventing Heat Illnesses in the BLAZING Summer Heat
This tech tip about preventing heat illnesses covers information and resources from the Cleveland Clinic, the U.S. Centers for Disease Control and Prevention (CDC), the U.S. Occupational Safety and Health Administration (OSHA), and the National Oceanic and Atmospheric Administration (NOAA). HVAC School is NOT an official OSHA training resource, and although these safety tips are […]
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What is RS-485 Communication?
This tech tip about RS-485 communication is the third installment in a four-part series about oscilloscopes. It’s a primer for the final installment about using an oscilloscope for diagnosis. I owe a special thanks to Jeremy Smith for sharing the information on Danfoss and for sparking my curiosity surrounding this type of communication. Let’s talk […]
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A2L Dissipation Boards and Leak Sensors
The HVAC industry’s ongoing shift towards eco-friendly solutions continually introduces new challenges and learning opportunities. A2L refrigerants are at the forefront of this transformation, offering a lower global warming potential (GWP) than many of the refrigerants weโ€™ve been using. A2L refrigerants are also mildly flammable, meaning they require some enhanced safety measures; one of these […]
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Oscilloscope Systems and Settings
This is part two of our four-part series on oscilloscope fundamentals. Special thanks to Andrew Holden for his contributions. In our last tech tip on oscilloscopes, we learned about some safety basics, waveforms, and measurements. Weโ€™re going to dive a little deeper into systems and settings on the oscilloscope in this tech tip. Systems are […]
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Iโ€™ve Done It This Way for 20 Years โ€“ And Thatโ€™s the Problem
Every trade has its favorite phrases. One of the most common in HVAC goes something like: “Iโ€™ve been doing it this way for 20 years and never had a problem.” When you hear thatโ€”or when you catch yourself saying itโ€”itโ€™s worth stopping to think. Usually, what that sentence really means is: “Iโ€™ve been doing it […]
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Oscilloscopes 101
This tech tip is the first in a four-part series on using oscilloscopes. I’d like to give a special thanks to Andrew Holden for his contributions to this particular tech tip. When we want to measure voltage between two points, we reach for a multimeter. A multimeter can tell us the average electrical potential between […]
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Estimating Made Easy with Unity Build
Many of you may already know that our HVAC company, Kalos Services, is also a GC. We do a lot of construction projects with HVAC, plumbing, and electrical scopes of work. Estimating is a crucial part of winning those projects, and those of you who work on HVAC for new construction probably already have an […]
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Buck-Boost Transformers
HVAC systems often fail early or don’t perform well due to inconsistent power. While technicians can’t control a home’s main power supply, they can stabilize it at the system using buck-boost transformers. These devices adjust voltage up or down to meet the equipmentโ€™s needs. As HVAC systems become more advanced, understanding buck-boost transformers will be […]
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Upgrading a Single-Pole Contactor with a SureSwitch: Using a Wiring Diagram
Along the path to becoming a great HVAC technician lies the dreaded wiring diagram. It’s meant to be a helpful map of the equipment’s electrical system, but with its crisscrossing lines and cryptic symbols, it often feels more like a barrier than a guide. If this sounds familiar, you’re not alone. But what if you […]
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Videos:

Podcasts:

Heat Exchanger Crack Comment – Short #280
๏ปฟ๏ปฟ In this short podcast episode, Bryan responds to a comment we received about cracked heat exchangers and how they were characterized in a recent combustion safety podcast episode. In reality, heat exchanger cracks counter the effects of the inducer motor.ย  The inducer pulls air through the heat exchanger, but a crack causes the inducer […]
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Dehum Innovations and Essentials w/ Nikki K.
๏ปฟ๏ปฟ๏ปฟ In this live episode recorded at the AHR Expo 2026 Podcast Pavilion in Las Vegas, host Bryan sits down with longtime friend and industry expert Nikki Krueger of Santa Fe and AprilAire. Nikki brings over 15 years of experience in indoor air quality and whole-home dehumidification to the conversation, having started her career with […]
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Lifetime of HVAC/R w/ John Pastorello – Short #279
๏ปฟ๏ปฟ In this short podcast episode from AHR Expo 2026, Bryan sits down with John Pastorello for a discussion about the latter’s lifetime of HVAC/R. John was a chemist and an HVAC technician before founding Refrigeration Technologies in 1987, and he received the HVAC Tactical Lifetime Achievement Award in 2026. Prior to entering the trade, […]
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Vapor Injection + Modulation Innovation w/ Copeland
๏ปฟ๏ปฟ In this live episode from the AHR 2026 Podcast Pavilion, Bryan sits down with Copeland’s Josh Souders (Manager of Commercial Unitary Product Management) and Jeff Kukert (Compression Senior Technical Trainer) to dive deep into Enhanced Vapor Injection (EVI) technology and its transformative impact on HVAC systems. This conversation offers both technical professionals and industry […]
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TXV vs. EEV – Short #278
๏ปฟ๏ปฟ In this short podcast episode, Bryan breaks down the differences between a thermostatic expansion valve (TXV) and an electronic expansion valve (EEV). He highlights their strengths and weaknesses. In the basic refrigerant circuit, the metering device drops the pressure. TXVs and EEVs are both metering devices that cause the liquid refrigerant to drop in […]
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Electric Heat Talk w/ Bert
๏ปฟ๏ปฟ In this informative episode, host Bryan welcomes guest Bert for an in-depth discussion on the often-overlooked but critically important topic of electric heat in HVAC systems. The conversation takes listeners through both the common and uncommon issues that arise with electric heat installations, offering practical insights drawn from years of field experience. Bryan and […]
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Gas & Combustion Safety w/ Bert
๏ปฟ๏ปฟ In this informative episode, Bryan and Bert dive deep into gas appliance safety and combustion analysis from the unique perspective of Florida HVAC technicians. While they humorously acknowledge that Florida’s mild winters mean they don’t work on gas furnaces daily, they make a compelling case that this actually makes their training even more critical. […]
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Why Square Footage โ‰  Tonnage – Short #276
๏ปฟ๏ปฟ In this short podcast episode, Bryan dives a bit into equipment sizing rules of thumb and why square footage does NOT equal tonnage in today’s world. Many rules of thumb exist in the industry, and one is a load calculation rule stating that you can size the HVAC for a house at 500 square […]
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Combustion vs. Compression – Short #275
๏ปฟ๏ปฟ In this short podcast episode, Bryan covers the history of the great heating debate: furnaces vs. heat pumps or combustion vs. compression. He also gives a breakdown of each other’s strengths and gives his two cents on the winner of the debate. Fire kept humans warm for much of history, but engineers developed a […]
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