BACK
Tool Selection: Manometers for the Right Job
Condenser Fan Blade Placement
Tool Selection: Analog vs. Digital vs. Probes
Two Ways to Prevent Freezing in 90%+ Furnace Condensate Lines
Decoding Measurement Lingo
History of Thermometry and the Invention of Thermometers
It’s All Relative… Humidity
The Heating Sequence of Operations and Onions
Electronic Expansion Valve Troubleshooting
Compressor Ohm Mistakes w/ Bert
Motor Ambient Rating – Short #241
Superheat Talk w/ JD Kelly
How to Deal w/ Too Much – Short #240
Delta T Talk w/ JD Kelly
Fire Sprinklers – Short #239
The PATH to High Performance HVAC w/ David Richardson
Nylog, Oil? Where does it go? – Short #238
Growing your HVAC Business the Smart Way w/ Copeland
#hvac
Tech Tips:
Last week, we briefly looked at the spec sheet of a gauge manifold. All things considered, it was quite short; we only had to worry about the refrigerant types, pressure ranges, and hose diameters. However, manometers’ spec sheets are quite a bit longer than gauge manifolds’ because they have resolution and accuracy specs, among other […]
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In a previous article, I talked about wiring permanent split capacitor (PSC) condenser fan motors. While researching the topic, I realized that there isn’t as much information available on condenser motors as there is on their counterpart—the indoor blower motor. I had never really given it much thought, as I assumed that the condenser motor […]
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The original tools of the trade were all analog: electrical meters, gauges, and even manometers (Magnehelic, anyone?). However, digital tools have also become a staple of the skilled trades—where would most of us be without digital multimeters? And then probes also joined the fray with the rapid improvements to smartphone technology over the last 15–20 […]
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This tech tip came from an email sent by Adam Blunkall, a Tennessee-based HVAC technician. He shared some tips to help prevent the issue of freezing in 90%+ furnaces in his market, and we appreciate his insight. Thanks, Adam! If we’re draining our 90%+ furnaces (or any condensing heating system) outside the structure in a […]
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Troubleshooting and commissioning are entirely data-dependent processes. How can you know that a system is undercharged unless you measure the superheat and subcooling? How can you know how much static pressure a blower motor has to overcome? In both cases, we use tools and measurements to help us determine the next steps. However, using the […]
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So, what is thermometry anyway? Thermometry is the scientific study of measuring temperature and has roots that date back to as early as 220 BC. During this time, Philo of Byzantium began to study the effects that temperature had on air. Specifically, he observed expansion and contraction caused by temperature change. He did this using […]
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Florida’s got a lot of great qualities: some pretty neat wildlife, beaches all around, and theme parks. On the flip side, Florida also has hurricanes and a lot of humidity. As much of a pain as it might be for residents and contractors alike, humidity is one of my favorite topics. We see relative humidity (RH) […]
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Just like Shrek, I like to think about the heating sequence of operations as an onion—it has layers. And each layer builds upon the previous one. We have written previously in great detail about gas furnaces, from top to bottom. I want to focus today on why there is a sequence of operations and how […]
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Electronic expansion valves (or EEVs) are metering devices that you’ll find in a variety of modern HVAC equipment, including heat pumps, VRF units, inverter mini splits, and chillers. This valve is electronic rather than mechanical and can precisely control the flow of refrigerant into the evaporator and optimize efficiency for heating and cooling units. Other […]
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Videos:
Podcasts:
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 […]
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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 […]
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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 […]
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In this short podcast, Bryan talks about how to deal with too much at work and in life. He gives some practical tips to help you when you feel overwhelmed. One of the best ways to get ahead is to wake up early, exercise, get sunlight, stay hydrated, eat healthy, and get enough sleep. […]
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Bryan from HVAC School interviews JD Kelly, known as “student of HVAC” on Instagram, about Delta T measurements in HVAC systems. This episode dives into the fundamentals of Delta T, common misconceptions, and proper measurement techniques. JD explains that Delta T is simply a temperature difference between two points of the same medium, which […]
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In this short podcast episode, Bryan talks about fire sprinklers and how to avoid setting them off on job sites. Fire sprinklers have an element in the center that expands when exposed to heat (like a TXV sensing bulb) and breaks the glass. When the glass breaks, the fire sprinkler starts pouring out water. […]
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In this engaging session, David Richardson breaks down the concept of high-performance HVAC, offering a clear roadmap for industry professionals looking to elevate their craft. Richardson argues that the HVAC industry has long been focused on equipment rather than complete systems, leading to widespread inefficiencies. The average system delivers only about 57% of its […]
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In this short podcast, Bryan answers a listener-submitted question about Nylog, oil, and where you put them when you're making flares. Nylog is a thickened refrigerant oil (which is either POE for Nylog Blue or mineral oil for Nylog Red), and it's miscible with the refrigerant and moves with it through the circuit. You […]
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In this episode of the HVAC School podcast, Bryan and Jim discuss strategies for growing an HVAC business, focusing on the importance of maintenance contracts, consistent service, and effective branding. Drawing from Jim's 15 years of experience running a successful HVAC company in California, they explore how maintenance contracts not only provide consistent revenue […]
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