Tech Tips

As we often do in these tech tips, we will start with the common and more practical explanation of saturation and then move to the more technical and nerdy explanation later. When we say “at saturation” or “saturated” in the HVAC/R trade, we are generally referring to the refrigerant that is in the process of […]

How does a typical single phase motor know how fast to run? Typical induction motors are dependent of the electrical cycle rate of the entering power (measured in hertz) for their speed. Our power in the US makes one complete rotation from positive electrical peak to positive peak 60 times per second or 60hz (50hz […]

First, let's get something straight: BRAZING is when you use a filler rod that isn't the same material as the base metal but melts ABOVE 840°F. Soldering is the same but at temperatures BELOW 840°F. With HVAC rods melting at around 1200°F, it confuses me why we usually call it “silver solder” but also often call it […]

Did you know that electrical terminals have a torque value? Yeah, I didn’t either for a long time. “Tight” worked well enough, but I’ve seen a few connections overheat after a while, and now I wonder… Did you know that tightening electrical screw terminals to their torque specs is part of the NFPA 70/National Electrical […]

Some quick basics – An ohmmeter is used to measure the resistance to electrical flow between two points. The ohmmeter is most commonly used to check continuity. Continuity is not a “measurement” as much as it is a yes/no statement. To say there is continuity is to say that there is a good electrical path […]

Friction rate is a value located on a ductulator. We use it during the design phase of a duct system to predict the operating static pressure of a duct system. The challenge with friction rate is that it is often misapplied by folks using a rule of thumb (ROT). In order to apply friction rate properly, […]

There have been several past posts on our Facebook group page about a concept called bypass dehumidification. I think technicians could benefit from learning more about this topic.  Bypass dehumidification or airflow is an interesting method for utilizing mixed air temperatures to maximize a system’s dehumidification capabilities. It's also a means of supplying adequate air […]

Let’s face it, refrigerant leak detection and prevention will always be important in our trade. Whether we’re dealing with leaks from corrosion or poor connections, we will always run into them in some form. We’ve touched on refrigerant leak prevention and detection quite a lot at HVAC School. Many of our articles, podcasts, and videos […]

In the residential HVAC industry, technicians are faced with customers every day. Each interaction presents its own set of unique challenges since no two customers are ever the same. While the variety of people we may encounter is wide, the HVAC technician's variety of soft skills and intuitive ability to communicate needs to be even […]