Tech Tips

There was a question in the Facebook group a few days ago about averaging sensors. There are two common configurations/methods used for averaging. The first is simply a setting in a thermostat or control where it reads separate sensors, and then the thermostat itself averages out the readings using its software. For example, if the […]

I recently received a message asking for a discussion of relative humidity (RH), wet-bulb (WB), and dry-bulb (DB). Time and time again, I hear techs say that condensation occurs when “hot meets cold,” which may be true in some cases. However, that is only a shorthand way to describe it and doesn't really address what […]

This article was written by Sam Myers with Retrotec. Thanks, Sam! If you’ve ever lived in a historic home, you’ve likely noticed that the level of comfort can change throughout different parts of the house. It can also typically change throughout different times of the year, depending on your climate. That is primarily due to […]

The general law of perfect gas is a combination of Boyle’s and Charles’s laws. Each of those laws neglected pressure, temperature, or volume in their formulas. The law of perfect gas combines the two, clearly establishing the relationship between all three variables and giving those laws a much more practical use in our field. We […]

We’ll never run out of content to discuss as long as thermostatic expansion valves exist. Deal with it. Today, we’re going to focus on the powerheads of TXVs. This article will focus on what the powerheads do, how they work, and some basic troubleshooting procedures involving TXV powerheads.   What is a powerhead, and where […]

This article was submitted by Genry Garcia of Comfort Dynamics, Inc. It is the second part of his series on zonal pressure diagnostics. Thanks, Genry! In Part 1 of this series, we outlined the basic understanding of ZPD—what it means and what it does. Most importantly, we showed how an effort to simplify a fairly […]

DISCLAIMER: HVAC School is NOT an official OSHA safety training resource! Although we provide safety tips in good faith, our website is not a substitute for safety training from an authorized OSHA training source. Although we primarily work with our hands, our eyes are one of our most valuable assets in the industry. After all, […]

DISCLAIMER: HVAC School is NOT an official OSHA safety training resource! Although we provide safety tips in good faith, our website is not a substitute for safety training from an authorized OSHA training source. We have already touched on safety in previous tech tip features about recovery tanks, as recovering refrigerant can be a surprisingly […]

John Dalton was an English chemist and physicist born in 1766. He was born into a Quaker family of tradesmen, though he and his brother became teachers early in life. His family bought a Quaker school in Kendal, where he and his brother taught around 60 students.  Dalton separated from the church as a young […]