HVAC School - For Techs, By Techs
Real training for HVAC (Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.
Episodes
Mastering Your Meter Advanced Functionality with Louise Kellar (UEi Test Instruments)
In this episode, Bryan welcomes back Louise Kellar of UEi Test Instruments for a deep dive into getting more out of a digital clamp meter than the basic volts, amps, and ohms most techs rely on every day. The tool in the spotlight is UEi's High Accuracy Clamp Meter (HAC), which is accurate when dealing with the low current draws common on modern condenser fan and blower motors and is critical for
Premature Coil Failure in Ductless Mini-Splits & VRF Equipment - Short #303
In this short podcast, Bryan and Roman discuss premature coil failure in ductless mini-splits and VRF equipment. These coils are susceptible to a few different types of corrosion. Warmer coil saturation temperatures and shorter runtimes result in lower latent capacity; whatever moisture is on the coil dries on the coil instead of draining out. Minerals and chemicals (including chlorides from bl
Advanced Refrigerant Recovery: Best Practices for Diverse Systems and Environments
In this live episode, Bryan sits down with Jim Bergmann of measureQuick and NAVAC trainers Zane and Jesse Stewart for a deep, technician-focused conversation about advanced refrigerant recovery. The group covers diverse system types and environments, including low-ambient recovery. Recovery machines cannot pump straight liquid, which we need to be mindful of during service. That said, vapor-only r
The A2L & Refrigerant Transition - Short #302
In this short podcast episode, Bryan and Roman talk about the A2L & refrigerant transition again, particularly sensors on R-454B and R-32 equipment. Since the beginning of the A2L transition, we have seen the equipment evolve and begin requiring accessories, including refrigerant sensors and blower recirculation systems (BRS) or dissipation boards. In a BRS, the blower turns on and dilutes the re
Invented For Techs, by Techs: Inside Refrigeration Technologies' "The Lab"
In this episode, Bryan sits down with Mike Pastorello, owner of Refrigeration Technologies, and Ashley Lynds, director of education and brand management for Viper, to talk about the company's roots, its newest product launches, and where the brand is headed next. This podcast focuses on "The Lab" and how it integrates field technicians with product development. Refrigeration Technologies was built
The Ethics of IAQ – Testing vs. Remediation Conflicts - Short #301
In this short podcast episode, Bryan and Roman talk about the ethics of IAQ, particularly in terms of microbial growth testing vs. remediation conflicts, based on Roman's recent experience hiring a mold assessor and then a remediation expert in his home. Remediation is governed by S520 of the IICRC. Microbial growth is tricky because it is often hidden and has real health effects, but there is a h
Is 400 CFM per Ton Always Right? w/ Ty
400 CFM per ton is useful—until it isn't. In this episode, Bryan and Ty take on one of the trade's favorite rules of thumb. It can be a reasonable starting point for many systems under moderate, near-sea-level conditions, but it is not a universal target. Proper airflow depends on actual delivered capacity, sensible and latent load, air density, climate, manufacturer data, and what the system is s
The MERV 15 Filtration Physics - Short #300
In this short podcast episode, Bryan and Roman Baugh talk about indoor air quality and microbial control, specifically MERV 15 filter physics and how it all works when bringing in outdoor air. We filter indoor air to keep dust and particles off the equipment and keep them from circulating through the air. However, we also need to filter fresh air. While indoor air has several pollutants, including
Tips for Being On Call w/ Ty
In this episode, Bryan Orr sits down with Ty Branaman for a wide-ranging conversation about what it really takes to be a good on-call technician. They open by reminiscing about how dispatch technology has evolved over their careers — from pagers, radio codes, and outdated paper map books to MapQuest, early GPS units, and today's 24-hour dispatch systems. That trip down memory lane sets up the epis
The Florida "M-Word" – Legal Boundaries & Tech Communication - Short #299
In this short podcast episode, Bryan and Roman talk about Florida law and how it relates to the "M-word" (mold) and the legal boundaries our techs must respect when they communicate with customers. HVAC School and Kalos are NOT mold experts, but we have experience as HVAC professionals who encounter suspicious microbial growth in our market (and cannot diagnose or remediate mold). We cannot use th
Becoming a GRIT Host or Mentor w/ Leilani
In this episode, Bryan sits down with Leilani for an introduction to GRIT Camps — the hands-on program that brings skilled trades exposure to youth ages 12–17 through community events led by working tradespeople. Leilani explains that a GRIT Camp pairs recruited mentors with students for a day of modules covering safety, carpentry, electrical, brazing, and plumbing, including torch work, PVC and c
Behind the Drywall – The Psychrometrics of a Hidden Moisture Failure - Short #298
In this short episode, Bryan and Roman talk about the psychrometrics of a hidden moisture failure... behind the drywall. Roman had an indoor air quality and mold assessment in his own home, and he learned that there were active mold spores in his home; he shares what he learned from the experience. Roman had a bulk water issue from plumbing (though bulk water issues can also occur outside the buil
HVAC Education. What NOT to Do w/ Jim F., Roman B. and Craig M.
Join Roman Baugh, Craig Migliaccio (AC Service Tech), and Jim Fultz for an unfiltered conversation about training mistakes, teaching pitfalls, and educational failures in the HVAC industry. Recorded live at the 7th Annual HVAC/R Training Symposium, this candid discussion reveals what experienced educators wish they knew when they started. Learn from their mistakes so you don't have to make the sam
Q&A What Uninsulated Refrigerant Lines Really Cost You - Short #297
In this short podcast episode, Bryan answers a question from Evan about the true cost of uninsulated refrigerant lines, especially in terms of efficiency losses and decreased longevity. Insulation keeps refrigerant cold, usually in the suction line; it makes it harder for cool vapor refrigerant to absorb heat. (Expansion lines are also insulated.) When that refrigerant picks up heat, that heat has
Outdoor Air & Ventilation Strategies with John Semmelhack, Ty Branaman & Tim De Stasio
In this live-stream episode, Bryan is joined by Tim DeStasio, John Semmelhack, and Ty Branaman for a deep dive into residential ventilation — the often-overlooked "V" in HVAC. The group opens with quick life updates before launching into a wide-ranging conversation covering the three core ventilation strategies (circulation, extraction, and dilution), how tight home construction changes the ventil
Selecting a Replacement Motor - Short #296
In this short podcast episode, Bryan covers the points to consider when selecting a replacement motor, particularly blower motors and condensing fan motors in residential and light commercial applications. Horsepower and amperage both matter for matching, but they are not the only items to consider. We also have to consider phase (three-phase vs. single-phase), voltage, and RPM; those must match
Nailing a Job Interview w/ Refrigeration Mentor
In this episode, Bryan welcomes back Trevor Matthews from Refrigeration Mentor for a conversation focused entirely on nailing a job interview in the HVAC and refrigeration trades — whether it's a technician's very first shot at breaking into the industry or an experienced tech looking to move to a new company or specialty. Trevor opens up about his own rocky start, admitting he cycled through roug
Digital Tools and AI - "So Happy Together" - Short #295
This short podcast episode is Tyler Nelson's Bry-X presentation from the 7th Annual HVACR Training Symposium: Digital Tools and AI - "So Happy Together." Tyler is the Business Development Manager and Global Trainer at Sauermann Americas. Artificial intelligence (AI) is measured data, not an authority, and it will not replace techs. It may enhance technicians' abilities but must be used responsibly
HVAC Summer Service Calls: Rushing, Mental Fog & How to Stay on Your Game
In this episode, Bryan leads a live team meeting focused on getting technicians mentally and practically ready for the summer rush. He opens by asking the group to name what makes the season different, and the answers pile up quickly: higher call volumes, hotter attics, more irritable customers, and a nagging pressure to move faster than usual. Bryan distills these observations into a central them
The House Always Wins! A Class On Building Science Basics - Short #294
In this short episode from the Bry-X stage of the 7th Annual HVACR Training Symposium, Tessa Murry gives a class on building science basics: The House Always Wins! Tessa is a building scientist who works with TEC. Tessa's class is about how the house puts HVAC contractors in difficult situations. When people have indoor air quality or comfort concerns, the HVAC often takes the blame, even if the i
Compressor Failures, What and Why w/ Ty
In this episode, Bryan sits down with compressor teardown specialist Ty Branaman for a deep dive into what really kills refrigeration and AC compressors. After some lighthearted banter, the conversation quickly turns technical: Ty has spent years cutting apart failed compressors on video, and he explains why that practice matters so much. As he puts it, he is "all about making the invisible visib
Multi Position Valves and More - Short #293
In this short podcast episode, Bryan talks about multi-position service valves and more valve types. Many typical residential systems have brass service valves with a hex cap and Schrader ports; access happens solely through the Schrader ports (where the cores are). Schraders are restrictive and prone to leaking, and they don't have the ability to back-seat or front-seat. In applications where we
Triple Point In Water and CO2 w/ Andrew G. and Matthew T.
In this episode, Bryan is joined by Matthew Taylor, a supermarket refrigeration specialist whose expertise centers on CO₂ rack systems, and Andrew Greaves, Director of User Experience at NAVAC Tools, for the third installment of their series on triple-point evacuation. The conversation expands beyond water to bring CO₂ into the picture, exploring where the two refrigerants behave similarly around
Washing Commercial Coils and Water Challenges - Short #292
In this short podcast episode, Bryan talks about considerations for washing commercial coils and water challenges techs might face. Despite being the topic of debate within the last several years, cleaning coils matters and will affect performance. When washing coils, we use Refrigeration Technologies Viper cleaners (especially Venom Packs) when we actually need cleaners. No matter which cleaner y
Does AI Belong in Trades Education w/ Ty
Bryan opens this conversation with Ty Branaman, Head of Training at the GRIT Foundation, by digging into a question that anchors everything else in the episode: what is trades education actually for? Ty's answer is unambiguous — it's about people, not information. He describes his own struggle with traditional, reading-heavy instruction and explains how that personal experience shaped his teaching
Q&A System Oversizing - Short #291
In this short Q&A podcast episode, Bryan answers a question from Evan, a licensed mold assessment consultant, about system oversizing: What can be done when an HVAC system is oversized to control humidity and keep occupants comfortable? The extent of the problem will depend on how badly the equipment is oversized, whether it has any turn-down or staging, and how the latent capacity is set up. To m
Filters - MERV 13, Myths & More
In this episode of the HVAC School Podcast, Bryan sits down with Kelsey Hei and Andy Fox from 3M Filtrete to pull back the curtain on what really goes into a quality air filter. Most homeowners — and even some contractors — think of air filters as simple screens that catch dust, but as this episode makes clear, modern filter technology is anything but simple. From proprietary nonwoven fiber struct
From High Performance Medicine to High Performance HVAC - Short #290
In this short podcast from the 8th HVACR Training Symposium's Bry-X stage, Ken Davis shares his experience as an HVAC contractor who has brought vital experience from high-performance medicine to High-Performance HVAC. Ken's experience comes from developing high-reliability organizations (HROs). An HRO has a low fail rate in an industry where high fail rates aren't tolerated due to catastrophic co
Training The Next Generation of HVACR Technicians w/ Lenny Diaddario (Copeland)
In this episode of the HVAC School Podcast, host Bryan sits down with Lenny from Copeland to explore how one of the most respected names in HVAC and refrigeration is actively investing in the next generation of technicians. Lenny leads Copeland's aftermarket demand creation efforts, which includes everything from working with wholesale networks and trade shows to educational partnerships with scho
Communications Might Be Your Best Tool - Short #289
This short episode is Andy Holt's session from the Bry-X stage of the 7th Annual HVACR Training Symposium: Communications Might Be Your Best Tool. In this session, Andy covers some key communication and customer service principles that can help you become a better technician. In the end, customers won't remember your technical knowledge; they will remember how you made them feel, and that's why go
All About Airflow Testing w/ Eric Kaiser
In this session from the 7th Annual HVACR Training Symposium in Florida, Eric "Elk" Kaiser delivers a comprehensive workshop on airflow testing and measurement. Eric opens by challenging technicians to think beyond simply pointing an instrument at a duct and reading a number. Before selecting any tool, he argues, professionals must understand exactly what they are measuring — whether that is veloc
The Deep End with Roman Baugh: Live Call, Grounded Compressor, Mitsubishi Mini-Split
In this short podcast, Roman Baugh takes over with his new series, "The Deep End," where he shares tech support conversations. This time, Roman is on the other end of a live tech support call about a grounded compressor with an existing Mitsubishi mini-split (Mr. Slim heat pump). The unit in this case had an unclear service history due to the homeowner moving in recently. In this issue, the compre
Add Duct Renovations to Your Product Offerings
In this episode, HVAC veteran Adam Mufich of National Comfort Institute (NCI) pulls back the curtain on one of the industry's most overlooked problems: the majority of residential HVAC systems in the United States are not delivering the correct amount of airflow. Drawing on decades of hands-on experience, Adam opens up about his own journey from confident installer to humbled diagnostician, shari
Refrigeration Pulse Valves - Short #288
In this short podcast from the Bry-X stage of the 7th Annual HVACR Training Symposium, Matthew Taylor from Kalos Services introduces refrigeration pulse valves, which started as a solution for CO2 refrigeration systems and are now common in commercial refrigeration as a whole. He briefly explains how they work and describes their role in the refrigeration systems (and possibly commercial HVAC syst
Residential HVAC Install Process Improvement
In this candid team meeting, Bryan — a founder of Kalos Services and a veteran of residential HVAC — gathers his install crew to have an honest conversation about what goes wrong on the job. With summer around the corner and the workload about to spike, Bryan circles back to his roots in residential HVAC to lead a round-table discussion on the pain points his technicians face every single day. Rat
How to Teach Kids the Trades - Short #287
In this short podcast from the Bry-X stage of the 7th Annual HVAC/R Training Symposium, Ty Branaman and Leilani Orr talk about how to teach kids the trades. They share lessons they've learned from the GRIT Foundation and over their careers as trades and home educators. Their approaches have evolved over the years, and GRIT has also evolved quite a bit from its beginnings. Leilani and Ty have found
Geothermal – Back to the Basics w/ Brad Cooper
In this episode, Brad Cooper — second-generation HVAC technician, educator at Arkansas State University-Beebe (ASUBB), and CMHE-certified professional with HVAC Excellence — breaks down geothermal systems for everyday HVAC technicians. Brad brings a grounded, no-hype perspective to a technology that has long intimidated many in the trade. His central message is simple: if you already understand he
How to Make Online Training That Does Not Suck - Short #286
In this short podcast, Ruchir Shah and Dan Riggs from SkillCat talk about how to make online training that does not suck! They talk about how to develop training that is relevant to the trades and can be applied in real-world trade work. The skill gap is widening in the trades, especially as shortages grow when people retire and it becomes more difficult to hire qualified new people. Hiring appren
The Vacuum Deep Dive: Microns, Moisture, and Molecular Science
In this action-packed live stream episode of HVAC School, host Bryan is joined by Eric Kaiser, Ty Branaman, and Roman Baugh for a continuation of a deep-dive conversation on vacuum practices — picking up where a previous episode left off with Andrew Greaves and Jim Bergmann. The team sets out to both reinforce the foundational best practices every HVAC technician should follow and to explore some
Surge Protection for HVAC - Short #285
This short podcast is from the Bry-X stage of the 7th Annual HVACR Training Symposium: Cheryl Klein's "Surge Protection for HVAC." Cheryl is with DITEK, a veteran-owned company based in Florida, and has extensive knowledge of whole-home surge protection and HVAC-specific surge protectors. HVAC systems may have their lifespans reduced by power surges (tens of thousands of volts within microseconds)
20 Years in Family Business from the Kalos Founders
In this special live panel session recorded at the 7th Annual HVAC/R Training Symposium, the three founders of Kalos Services — Bryan Orr, his father Robert (Bob) Orr, and uncle Keith Huntington — sit down together to celebrate the company's 20th anniversary and answer questions from the audience and online attendees. Hosted by Bert, the conversation blends humor, hard-earned wisdom, and surprisin
Permanent Load Reduction As a Sales Driver - Short #284
This short podcast episode is Jeremy Begley's Bry-X session from the 7th Annual HVACR Training Symposium: "Permanent Load Reduction in HVAC – The Hidden Driver of Long-Term Sales." Some common customer complaints we hear as HVAC contractors include high humidity, high electric bills, noise, and uncomfortable rooms. The typical HVAC solution is to change the equipment or ductwork, such as by downs
Cold Climate Evacuation Livestream - Pandora's Box
In this long-awaited live episode of HVAC School, host Bryan Orr reunites with three industry veterans — Jim Bergmann of measureQuick, Roman Baugh (Kalos), and Andrew Greaves of NAVAC — to tackle one of the most pressing and underaddressed challenges in modern HVAC: performing refrigerant recovery and system evacuation in extreme cold-weather conditions. The conversation was sparked by a real-worl
Training Refrigeration: Building Technicians Who Think, Not Just Fix - Short #283
Training the refrigeration technician is about building technicians who think, not just fix. In this engaging conversation from the 7th Annual HVAC/R Training Symposium, host Trevor Matthews sits down with Billy Carlson to explore what it really takes to develop technicians who think critically and troubleshoot effectively. Billy shares his journey in the HVAC/R industry, from residential air cond
Succession in Family Business w/ TruTech & Kalos
In this special collaborative episode between the Building HVAC Science Podcast and HVAC School, host Bryan Orr sits down with his father and co-founder Robert Orr (Kalos) and Bill and Billy Spohn, the father-son duo behind TruTech Tools, for an in-depth conversation about the realities of running, transitioning, and ultimately passing the torch in a family-owned business. What makes this episode
Adding Plumbing To Your HVAC Business - Short #282
Looking to Add Plumbing To Your HVAC Business? Learn the critical pitfalls to avoid before you make the leap! In this livestream from the 7th Annual HVAC/R Training Symposium, service plumber and third-generation tradesman Nate Agentis breaks down why adding plumbing to your HVAC business isn't as simple as hiring a plumber and stocking PVC on your trucks. What You'll Learn: Why most HVAC compani
Troubleshooting Tips and Tricks w/ Let's Be Techs
In this episode of the HVAC School Podcast, host Bryan sits down with Johnny, the creator behind the popular social media channel "Let's Be Techs." Johnny brings a wealth of hands-on experience to the table, having spent his first 13 years in residential HVAC before transitioning into commercial refrigeration. He shares his unconventional path into the trade—starting out building houses before bei
Heat In....Heat Out: All About Heat Transfer w/ Joe Joe The HVAC Man - Short #281
Join Joey Henderson LIVE from the 7th Annual HVAC/R Training Symposium in Florida! This essential training breaks down the science of heat transfer into practical field techniques every technician needs. What You'll Learn: Understanding sensible heat (dry bulb) vs latent heat (wet bulb) removal Why airflow matters Heat transfer diagnostics BEFORE pulling out gauges Gas furnace temperature rise tr
Building Science at the Kitchen Table: Using Testing to Close the Sale
Recorded live at the 7th Annual HVACR Training Symposium, this episode brings together Roman from HVAC School and building science practitioner Brynn for a deep-dive conversation on one of the most pressing challenges in the HVAC industry: how contractors can use building science principles not just to solve problems, but to communicate value and close sales at the kitchen table. With 26 years of
Hard Lessons w/ Roman, Tim D., Nathan O. and ELK
Join industry veterans Tim De Stasio, Roman Baugh, Eric Kaiser, and Nathan Orr as they share their most memorable HVAC lessons learned the HARD WAY. This unfiltered conversation from the 7th Annual HVAC/R Training Symposium reveals the real stories behind costly errors, dangerous situations, and valuable HVAC training moments that shaped their careers. What You'll Learn: Critical refrigerant hand
Better Seen than Viewed w/ Jim Bergmann
In this heartfelt and wide-ranging episode, host Bryan reconnects with Jim Bergmann of measureQuick after nearly three years apart. The reunion is anything but ordinary — Jim opens up about a serious battle with non-Hodgkin's B-cell lymphoma that sent him through not one but two rounds of chemotherapy, ultimately requiring a cutting-edge CAR-T cell immunotherapy treatment at the Cleveland Clinic.
Symposium - What Good Techs Do Different W/ Data
Discover what separates elite HVAC technicians from average ones in this eye-opening session from the 7th Annual HVAC/R Training Symposium. Shelby Breger, co-founder of Conduit Tech, and Jim Bergmann, President of measureQuick, reveal what good HVAC techs do differently with data and how they leverage data to transform their diagnostics, commissioning, and service work. What You'll Learn: Why top
Heat Recovery from Data Center w/ Jeff Staub
In this episode of the HVAC School Podcast, host Bryan sits down with Jeff Staub, Director of OEM Sales for Danfoss North America, to explore one of the most rapidly evolving frontiers in the HVAC and refrigeration world: thermal management for AI data centers. With nearly 30 years of industry experience spanning technical support, application engineering, and product development, Jeff brings deep
All About ESCO with Renee Tomlinson and MeasureQuick's Latest Features with Jim Bergmann
In this short episode, the HVAC School team members talk with Jim Bergmann (measureQuick) and Renee Tomlinson (ESCO) about the latest and greatest that they brought to their booths at the 7th Annual HVACR Training Symposium. First, JD Kelly spoke with Renee about ESCO Institute's educational offerings. ESCO offers a mix of books and online training content, including new training for A3 refrigeran
Building Tools & the Trade w/ Tony G. from Fieldpiece
Recorded live on the third day of the AHR Expo 2026 in Las Vegas, Nevada, this episode of HVAC School brings together host Bryan and longtime friend of the show Tony Gonzalez, Director of Training at Fieldpiece Instruments. The conversation kicks off with some light-hearted banter about trade show survival tips — including the classic trick of hanging around near closing time to score free gear fr
Symposium - Do Inverters Suck?
Join us for this eye-opening session from the 7th Annual HVAC/R Training Symposium featuring industry experts Roman Baugh, Jon Esquivel, and Adam Mufich as they expose the truth about inverter-driven HVAC systems. What You'll Learn: Common Inverter Problems - Why these systems fail and how to prevent callbacks Design Mistakes - Oversized inverters acting as expensive single-stage units Dehumidifi
Recovery Pro Tips w/ Jesse from NAVAC
Recorded live on the floor at the AHR Expo 2026, this episode of the podcast brings together host Bryan and his guest Jesse, National Training Manager at NAVAC, for a candid, high-energy conversation about professional best practices in the HVAC/R trade. The two have a long-standing friendship and professional rapport that makes the discussion feel both educational and genuinely entertaining. Jess
Symposium - What is the House Trying to Tell Me?
Join Chris Hughes and Adam Mufich at the 7th Annual HVAC/R Training Symposium as they interview building scientist Tessa Murray. In this eye-opening conversation about what your house is really trying to tell you. Discover why HVAC techs need to understand building science fundamentals to truly master their craft. What You'll Learn: The critical connection between HVAC systems and building scienc
Don't Die! w/ Louise from UEi
In this episode, recorded live at AHR Expo 2026, Bryan sits down with Louise from UEi Test Instruments for an in-depth conversation about one of the most underestimated dangers in the HVAC trade: carbon monoxide. Rather than treating CO as just another checkmark on a safety list, Bryan and Louise dive into the full history of the gas — all the way back to early publications from 1922 and 1923 that
Heat Exchanger Crack Comment - Short #280
In this short podcast episode, Bryan responds to a comment we received about cracked heat exchangers and how they were characterized in a recent combustion safety podcast episode. In reality, heat exchanger cracks counter the effects of the inducer motor. The inducer pulls air through the heat exchanger, but a crack causes the inducer to pull the air from elsewhere, especially once the blower mot
Dehum Innovations and Essentials w/ Nikki K.
In this live episode recorded at the AHR Expo 2026 Podcast Pavilion in Las Vegas, host Bryan sits down with longtime friend and industry expert Nikki Krueger of Santa Fe and AprilAire. Nikki brings over 15 years of experience in indoor air quality and whole-home dehumidification to the conversation, having started her career with AprilAire before moving to Santa Fe (formerly Ultra Aire) — and now
Lifetime of HVAC/R w/ John Pastorello - Short #279
In this short podcast episode from AHR Expo 2026, Bryan sits down with John Pastorello for a discussion about the latter's lifetime of HVAC/R. John was a chemist and an HVAC technician before founding Refrigeration Technologies in 1987, and he received the HVAC Tactical Lifetime Achievement Award in 2026. Prior to entering the trade, John was a chemist in a lab. He applied for and was hired by an
Vapor Injection + Modulation Innovation w/ Copeland
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 newcomers a compr
TXV vs. EEV - Short #278
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 pressure and become a liquid-vapor mixture;
Electric Heat Talk w/ Bert
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 Bert balance technical ex
Vapor Diffusion Ports, Hygric Buoyancy, and Fruit - Short #277
In this short podcast episode, Bryan talks about some building science concepts, including vapor diffusion ports, hygric buoyancy, and... fruit packaging? Much of building science wisdom over the past couple of decades has dealt with air sealing (just seal it tighter!). However, building tightness has a darker side: more difficulty drying. When buildings can't dry, moisture accumulates and leads t
Gas & Combustion Safety w/ Bert
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. When technicians only encounter gas applianc
WHY SQUARE FOOTAGE ≠ TONNAGE - Short #276
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 feet per ton. Old houses are leaky and poorly insulated compared to new homes, which results in large energy l
EPRs and Rack Refrigeration w/ Matthew Taylor
Matthew Taylor delivers an expert-level presentation on EPRs, building on his previous work on parallel rack systems. While his earlier content focused on the similarities between air conditioning and refrigeration, this session explores what makes commercial refrigeration unique—particularly the critical role of EPRs in maintaining optimal operating conditions across multiple evaporators running
Combustion vs. Compression - Short #275
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 way to move heat by manipulating refrigerant pressures. Early heat pumps got a bad rap
HVAC In the Northeast w/ Leo & Paul Sharkey
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 years. Their engineering backgrounds bring a refreshing, data-driven perspectiv
Superheat in Heat Mode: Why Heat Pumps Get Weird - Short #274
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 to move heat in very cold conditions, we need very low suction pressures and cold
What We Learned From NCI Duct / Balancing Training
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 their customers.
HVAC Systems for Architects: Making Sense of the Alphabet Soup - Short #273
In this short podcast, Bryan answers a question submitted to HVAC School by an aspiring licensed architect who wanted to learn more about the many different types of HVAC systems. The three main buckets of HVAC systems are air-to-air, water-source, and air-to-water. Air-to-air systems move air around to remove heat from one space, and that heat is rejected to the air somewhere else. Water-source s
Sizing Breakers and Conductors (for HVAC) – Have Things Changed?
In this essential episode, Bryan Orr sits down with Elliot, the residential install supervisor at Kalos Services, to unpack a critical issue that's causing confusion among HVAC technicians, electricians, and inspectors alike: the new standards for breaker and conductor sizing on inverter-driven equipment. The conversation was sparked by Elliot's frustrating experience of having two inspectors in
Absorption Cooling - The Rise and Fall and Rise - Short #272
In this short podcast episode, Bryan goes on another history journey, retelling the story of the rise and fall and rise of absorption cooling. Some of the first HVAC/R engineers cooled buildings with fire; they used absorption refrigeration, which ran on heat instead of electricity. In the early 1800s, French scientist Michael Faraday showed that gases like ammonia could absorb heat as they evapor
Combustion Analysis w/ Tony G.
In this comprehensive training session from the symposium, Tony Gonzalez, Training Director at Fieldpiece, delivers an engaging and practical guide to combustion analysis for HVAC technicians. With 25 years of experience at Fieldpiece—from warehouse worker to training director—Tony brings both technical expertise and real-world application to this 50-minute interactive session focused on the comp
Give Until it Hertz - The Battle Over Frequency - Short #271
In this short podcast episode, we go back into the history of the trades, namely the battle over frequency (and how each side had to give until it hertz). The low hum of motors is alternating current: electricity moving back and forth through copper 60x per second (in the USA and Canada, at least). In another version of history, that pulse could be 50x per second instead (as in much of the remaind
Residential vs. Commercial HVAC Sales
In this candid conversation, Nathan and Bryan dive deep into the often-misunderstood world of sales in the construction and HVAC trades. Nathan, who has transitioned from fieldwork to spending roughly 60% of his time in sales, offers a unique perspective on why sales professionals are necessary despite the skepticism they face from tradespeople. The discussion tackles head-on the negative percept
When Ammonia Ruled the World - Short #270
In this short podcast episode, Bryan takes us on a history journey back to when ammonia ruled the world. In the mid-1800s, before R-12, many inventors and scientists experimented with vapor-compression refrigeration systems to make ice. They used a variety of refrigerants in their patents, including ether, ethyl ether, carbon dioxide, sulfur dioxide, methyl chloride, and ammonia. Each one had trad
