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Joe Shearer
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Tech Tips written:

Does Air or Nitrogen Absorb Water?
There are many examples of teaching using metaphors to help someone grasp how something works without being EXACTLY correct. Some examples are how we often use water flow to explain electrical flow or refrigerant circuit dynamics. It's enough like the way it works to get our heads wrapped around it, but there are many differences. […]
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Why A/C Systems Freeze
Let's start with the basics. Water freezes at 32° Fahrenheit (0° Celsius) at sea level and at atmospheric pressure. When any surface is below that temperature, and the air around it contains moisture, ice/frost will form. You can see how water freezes at the molecular level in the GIF below:   In some situations, ice […]
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Living in a World of Acids (and why HVAC coils are secretly crying for help)
Imagine a small IT room packed with servers, monitors, and humans. CO₂ levels easily spike to over 3000 PPM since the room lacks fresh air ventilation. Two overworked mini-split units churn away, cooling the space and unknowingly creating the perfect acidic environment. Fast forward a few months, and those shiny coils now resemble something pulled […]
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Expansion Valves – What Does and Doesn’t Matter?
   This podcast features a lively discussion on expansion valves, particularly thermostatic expansion valves (TXVs or TEVs), with a panel of expert guests – Corey Cruz (a market refrigeration tech), Matthew Taylor (head of refrigeration service at Kalos), and Joe Shearer (with Precision Air Conditioning). The conversation kicks off by busting some common myths […]
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Non-Condensibles
Eric Mele and Joe Shearer join Bryan to discuss the challenging issue of diagnosing and rectifying non-condensibles in the circuit. Non-condensibles are gases that don't condense, including nitrogen. These are NOT moisture or contaminants, and they can be tricky to diagnose; the pressure readings will likely be normal, but the charge will actually be quite […]
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