#hvac

If you own your HVAC company or are involved in management, you may have realized that our industry is currently facing a shortage of new A2L refrigerants, particularly R-454B and R-32.  Our own company has faced limited availability and long lead times, mainly due to supply chain disruptions and the increased demand now that our […]

I want to share something that came up in a recent discussion with Roman Baugh about VRF systems, and it made me realize I might have had a blind spot regarding scroll compressor designs. We were talking specifics, and he brought up high-pressure shell compressors. My immediate thought was, “Hold on, aren't scrolls low-pressure shell […]

There are three things we never discuss at the dinner table: religion, politics, and which wire to break with your float switch. A float switch fills with water whenever there is a drain backup, and it breaks power to one of the low-voltage wires. We clearly want the HVAC system to stop producing more condensate, […]

Being in an industry that requires a lot of travel—local or regional—can be a great thing for people who enjoy driving. It also comes with several more risks and opportunities for roadway accidents than someone who just has a round-trip commute to a single location every day.  We’re all aware of the issues of texting […]

A few times in the past, we’ve heard the phrase “the house is the biggest duct” because of the way air moves through it. Well, we can take it a step further and see that there are similarities that go just beyond air movement.  A building has several layers to keep things like moisture, heat, […]

Delta T is the difference in temperature between two points of the same medium. It is commonly used by scientists and engineers to analyze the amount of heat transfer in a system. In general HVAC terms, it is the measurable change in temperature between an air input and air output. However, it could also be […]

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. Many things may deter people from working in the HVAC industry. Perhaps surprisingly, exposure to heights could be the deal-breaker. (Not […]

This tech tip comes from a post in the HVAC School Facebook group by Ed Janowiak. Ed is the Manager of HVAC Design Education at ACCA, a longtime friend of HVAC School, and an educator who does a lot of great work for the industry. Thanks, Ed! This past Thursday, I taught a class where […]

In this article, we’ll discuss superheat while using this diagnostic sheet to help us better understand how it is calculated and from where it is derived. I want to thank Ty Branaman for helping me develop these sheets that will hopefully aid in a better understanding of some of the basic HVAC measurements that both […]

 In this episode of the HVAC School podcast, host Bryan Orr and guest Ty Branaman have an in-depth, hands-on conversation about the philosophy, structure, and impact of GRIT Camps—workshops designed to introduce kids to the trades through immersive, practical experiences. The episode opens with reflections on a recent successful GRIT Camp in New Jersey, […]

 In this short podcast episode, Bryan talks about band-aids, hacks, and ethics. He explores ethical “band-aid” solutions and how to charge for them. He also covers the difference between patching up equipment ethically and unethical repairs. Temporary fixes and ugly permanent fixes fall into the ethical gray area for a lot of people, especially […]

 In this episode, Bryan and Roman dive deep into the world of Variable Refrigerant Flow (VRF) systems, focusing on the persistent issue of compressor failures. VRF technology has evolved, and it has seen a major rise in the North American market since the early 2010s. Roman shares his passion for VRF, tracing its origins […]

 In this short podcast episode, Bryan talks about some no-serve situations he's encountered as a technician and HVAC business owner. He also talks about situations that may be unpleasant but aren't quite no-serve situations. Some common and obvious no-serve situations are when a client threatens a technician, especially with lawsuits, bad reviews, or even […]

 In this informative HVAC podcast episode, Bryan and Bert dive deep into the complex world of locked and internal overload compressors, focusing specifically on single-phase residential units. The discussion begins with Bert explaining one of the most common challenges technicians face: diagnosing a locked compressor. He describes how compressors that are locked will typically […]

 In this short podcast episode, Bryan covers some unique electrical cases: when 0v isn't safe. When you measure voltage, you're finding out the electrical potential between two points. Just because there is 0v between one point and another doesn't mean there will be 0v between those points and other points. Non-contact voltage detectors are […]

 In this episode, Bryan and Bert dive into the often misunderstood world of compressor testing, focusing on common mistakes technicians make when using ohmmeters, compressor testers, and megohm meters. The conversation highlights how diagnostic errors can lead to unnecessarily condemned compressors and wasted time and resources. The hosts begin by discussing fundamental concepts like […]

 In this short podcast episode, Bryan talks about what the ambient rating means on a motor. These ratings can be found on both condensing fan motors and blower motors. They have Cs in their rating, which represents the maximum ambient temperature the motor can handle in degrees Celsius (like 40C or 60C). Heat and […]

 In this episode of the HVAC School podcast, host Bryan discusses superheat with guest JD, who recently co-authored an article on the topic with Ty Branaman. The conversation explores the often misunderstood concept of superheat, its importance in HVAC diagnostics, and common misconceptions technicians have when measuring and interpreting it. Bryan begins by sharing […]