Tech Tips

Introduction Replacing a reversing valve is either every technician’s dream or nightmare. The sheer amount of brazing involved in confined spaces will inspire either delight or nightmares about the upcoming valve replacement. Fortunately, these emotional highs and lows are uncommon because we don’t diagnose and replace bad reversing valves very often.  That itself poses a […]

This article was written by Don Gillis with Chemours. Thanks, Don! There are 3 main reasons we use “P” or “U” traps: Assisting in oil return to the compressor Preventing oil accumulation in the evaporator  Preventing liquid refrigerant or oil from entering the compressor while operating or during the off cycle Assisting in oil return […]

Let's talk about the magic that is inverters and how to test the boards that drive this technology. Inverters play an extremely important role in household appliances, industrial machinery, and the rising popularity of household HVAC systems. Inverters consist of a wide variety of electronic circuitry, and there are many situations in which they need […]

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 […]

It’s that time of year again—the furnace service calls are peaking. It’s a good idea to crack open Jason Obrzut’s book, Gas Heating: Furnaces, Boilers, Controls, Components, and listen to the many public podcasts and presentations by experts like Jim Bergmann. At HVAC School, we’re fortunate to have had some of the industry’s greatest minds […]

A few years ago, a friend of mine, Clive Mitchell, aka Big Clive, explained the Dunning-Kruger concept while he was a guest on my YouTube-based podcast, “HVAC Overtime.” Clive is another content creator on YouTube specializing in technical videos where he reverse-engineers electronic devices. Clive has a very analytical mind; he sees patterns in people […]

DISCLAIMER: I have no financial interest in HVAC Simulator or Dirk’s company, Nauman Innovation Group LLC. He is not a sponsor; I just think he’s a great guy who cares a lot about the industry, and I’m excited to share his work with other people who want to improve training and education in the skilled […]

How do we decide what to spend our time and attention on as technicians? What is truly important and what isn’t? At least here in Texas, the answer changes seasonally. When it’s 100 degrees outside, your priorities shift from long conversations about people’s pets to conveying necessary information about system problems so we can get […]

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 […]