BACK
Refrigerant Recovery Cylinder Fill Calculations Simplified
Confirming Liquid Levels with a Little Thermodynamics
Lรฉon Creux’s Scroll Design: From Initial Failure to an Enduring Legacy
Traditional & Desiccant Dehumidification and When to Use Each (or Both)
Discovering Mental Reference Points
Three Levels of Acid Testing
Dedicated Dehumidifier vs. Electric Reheat Dehumidification – Who Yaย Got?
HH vs. EK Filter-Driers: Technical and Field Comparison
3 Ways to Reduce Compression Ratio in a Heat Pump
Vapor Injection + Modulation Innovation w/ Copeland
TXV vs. EEV – Short #278
Electric Heat Talk w/ Bert
Gas & Combustion Safety w/ Bert
Why Square Footage โ Tonnage – Short #276
Combustion vs. Compression – Short #275
HVAC In the Northeast w/ Leo & Paul Sharkey
Superheat in Heat Mode: Why Heat Pumps Get Weird – Short #274
What We Learned From NCI Duct / Balancing Training
#hvac
Tech Tips:
This tech tip about recovery cylinder fill calculations was written by Eric Kaiser from TruTech Tools. Thanks, Eric! Filling refrigerant recovery cylinders is a task HVACR technicians perform regularly, but figuring out how much refrigerant to safely put into a cylinder can still be confusing. The challenge almost always comes back to refrigerant density or […]
Read more
Maintaining the correct vapor-liquid refrigerant balance is crucial for air conditioning and refrigeration system performance. Longer line sets hold more refrigerant, which increases the risk of liquid accumulating in the suction line or entering the compressor during off-cycles. Heat pumps are one common application that requires additional measures. Refrigerant flow reverses during heating, turning the […]
Read more
The HVAC/R industry isnโt short on tragic figures. Thereโs John Gorrie, whose ice machine showed a lot of promise but didnโt have enough financial backing due to the lucrative ice industry and the death of his business partner. While Gorrie may have died without seeing his vision reach the masses, he was ahead of his […]
Read more
This tech tip about traditional and desiccant dehumidification is based on a conversation with Nikki Krueger and David Schurk. Nikki is a longtime contributor to HVAC School and is a relatively frequent podcast guest and symposium speaker. David Schurk is the Director of Applied Engineering and National Sales Manager at Innovative Air Technologies. Nikki specializes […]
Read more
Trying to wrap your head around HVAC can feel like a constant firehose of new info, right? Whether you’re in class or on the job, there’s just so much to soak up. And when you finally think you’ve got one thing down, BAM, here comes another concept. For me, remembering everything can be a real […]
Read more
Anytime we have a compressor failure, we canโt just pull out the bad compressor and drop a new one in. We have to put our detective hats on and find the culprit so that it doesnโt happen again. In many cases, acid is a prime suspect. Whenever thereโs acid in the system, the next compressor […]
Read more
This dehumidification tech tip was written by Tim De Stasio. He originally published it on his website, which you can visit HERE. Thanks, Tim! In March of 2024, I set out to better understand the cost of ownership and return on investment for two dehumidification strategies: a dedicated dehumidifier versus using electric reheat dehumidification from […]
Read more
When we think of HVAC system components, the big four come to mind: evaporator, compressor, condenser, and metering device. However, there are several accessories that keep the HVAC system working as intended, and the filter-drier is one we cannot ignore. Filter-driers protect HVAC/R systems by removing moisture, acids, and debris from refrigerant. In typical residential […]
Read more
Weโve talked about compression ratio a lot over the years. Compression ratio is the number you get when you divide the absolute head pressure (PSIG + 14.7) by the absolute suction pressure (PSIG + 14.7). It measures the efficiency of a compressor, and lower numbers indicate that the compressor is moving more refrigerant while consuming […]
Read more
Videos:
Podcasts:
๏ปฟ๏ปฟ In this live episode from the AHR 2026 Podcast Pavilion, Bryan sits down with Copeland’s Josh Souders (Manager of Commercial Unitary Product Management) and Jeff Kukert (Compression Senior Technical Trainer) to dive deep into Enhanced Vapor Injection (EVI) technology and its transformative impact on HVAC systems. This conversation offers both technical professionals and industry […]
Read more
๏ปฟ๏ปฟ In this short podcast episode, Bryan breaks down the differences between a thermostatic expansion valve (TXV) and an electronic expansion valve (EEV). He highlights their strengths and weaknesses. In the basic refrigerant circuit, the metering device drops the pressure. TXVs and EEVs are both metering devices that cause the liquid refrigerant to drop in […]
Read more
๏ปฟ๏ปฟ In this informative episode, host Bryan welcomes guest Bert for an in-depth discussion on the often-overlooked but critically important topic of electric heat in HVAC systems. The conversation takes listeners through both the common and uncommon issues that arise with electric heat installations, offering practical insights drawn from years of field experience. Bryan and […]
Read more
๏ปฟ๏ปฟ In this informative episode, Bryan and Bert dive deep into gas appliance safety and combustion analysis from the unique perspective of Florida HVAC technicians. While they humorously acknowledge that Florida’s mild winters mean they don’t work on gas furnaces daily, they make a compelling case that this actually makes their training even more critical. […]
Read more
๏ปฟ๏ปฟ In this short podcast episode, Bryan dives a bit into equipment sizing rules of thumb and why square footage does NOT equal tonnage in today’s world. Many rules of thumb exist in the industry, and one is a load calculation rule stating that you can size the HVAC for a house at 500 square […]
Read more
๏ปฟ๏ปฟ In this short podcast episode, Bryan covers the history of the great heating debate: furnaces vs. heat pumps or combustion vs. compression. He also gives a breakdown of each other’s strengths and gives his two cents on the winner of the debate. Fire kept humans warm for much of history, but engineers developed a […]
Read more
๏ปฟ๏ปฟ In this engaging episode of the HVAC School podcast, host Bryan Orr sits down with Leo and Paul Sharkey, a father-son duo of mechanical engineers who made the leap into the HVAC business. Leo and Paul share their remarkable journey of purchasing an HVAC company in September 2020 and quadrupling its revenue within five […]
Read more
๏ปฟ๏ปฟ In this short podcast, Bryan answers a listener-submitted question and explains why heat pumps get a bit weird: when it comes to superheat in heat mode. He also explains how we can move heat from outdoors to indoors, even in temperatures below freezing (cold temperatures just have less heat, not zero heat). In order […]
Read more
๏ปฟ In this engaging and informative episode, Bryan sits down with Elliot to discuss his recent training experience with the National Comfort Institute (NCI), covering two intensive courses on duct system optimization and residential air balancing. The conversation offers valuable insights for HVAC professionals looking to improve their technical skills and provide better service to […]
Read more
