
Hosted by Bryan Orr · EN

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 HVAC company when he realized the financial opportunity in the trade. He eventually owned a contracting business, but he didn't truly make his HVAC/R chemistry debut until 1987 with Big Blu. When he noticed problems with existing liquid leak reactants and inaccurate electronic leak detectors, John developed Big Blu in his kitchen (with the help of his local library and patent office for research) and tested it in the field. Big Blu was the first Refrigeration Technologies product, and it was the only one for a while. He then developed Nylog in the early 1990s while developing a different product. After falling down research rabbit holes and doing lots of trial and error, he eventually realized the product's potential as an assembly lubricant, and Nylog became an official Refrigeration Technologies product. Even as Refrigeration Technologies continues to grow and has received several purchase offers, it remains a family business. John's son, Mike, became a mechanic but eventually decided to return to the business, and he runs it to this day. John's career culminated with the HVAC Tactical Lifetime Achievement Award, which is a testament to the service, education, and mentorship he has shared with the HVAC/R industry. Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

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 comprehensive look at how vapor injection is revolutionizing heat pump performance, particularly in challenging climate conditions. The discussion centers on how EVI technology addresses one of the industry's most persistent challenges: maintaining high heat pump capacity in extremely low-temperature conditions. Josh and Jeff explain that vapor injection can deliver up to 20% added capacity and 10% improved efficiency while simultaneously enhancing compressor reliability. This technology, which has been a staple in refrigeration applications for years, is now becoming increasingly prevalent in commercial and residential HVAC systems, especially as cold climate heat pumps gain traction across North America. The guests make the complex topic accessible by breaking down how the system works—taking liquid refrigerant from the condensing line, running it through an expansion device and brazed plate heat exchanger (economizer), and injecting the cooled vapor directly back into the compressor scroll at a specific intermediate point. What makes this episode particularly valuable is the practical guidance offered for field technicians. The conversation moves beyond theoretical explanations to address real-world implementation challenges and troubleshooting strategies. Josh and Jeff emphasize the importance of understanding operating envelopes, pulse-width modulated (PWM) valves, pressure transducers, and modern control systems. They introduce Copeland's latest product developments, including the YAW variable speed vapor injection platform (1.5 to 25 tons) and the upcoming YAB two-stage vapor injection system launching later in 2026. The discussion also touches on applications beyond traditional HVAC, including commercial water heating and boiler replacement systems where high discharge temperatures are crucial. Throughout the episode, the guests maintain an encouraging tone toward technicians who may feel intimidated by these advancing technologies. They stress that while EVI systems may appear complex with additional tubing, heat exchangers, valves, and sensors, the underlying thermodynamic principles remain the same. The key is familiarizing oneself with new components like PWM valves and modern controllers, and leveraging tools like Copeland Mobile to verify system performance against operating envelopes. This episode serves as both an educational resource and a call to action for HVAC professionals to embrace these emerging technologies that are rapidly becoming industry standard. Topics Covered Enhanced Vapor Injection (EVI) fundamentals – How EVI works, its history in refrigeration, and why it's now critical for commercial and residential HVAC applications Capacity and efficiency benefits – Achieving up to 20% capacity boost and 10% efficiency improvement, particularly in low-ambient heating conditions Compressor reliability improvements – How injecting cooled vapor into the scroll set manages discharge temperatures and extends compressor life under high compression ratios Operating envelope management – Understanding compressor operational limits and using tools like Copeland Mobile to verify field conditions stay within safe parameters Cold climate heat pump technology – Meeting DOE's Cold Climate Heat Pump Challenge requirements for 100% capacity at 5°F ambient conditions System architecture and components – Detailed explanation of economizers (brazed plate heat exchangers), pulse-width modulated (PWM) valves, pressure transducers, and advanced controllers Compression ratio challenges – Managing the increased work required when outdoor temperatures drop while indoor condensing temperatures remain constant New Copeland product platforms – Introduction to YAW variable speed vapor injection (1.5-25 tons), YAB two-stage vapor injection (launching 2026), and tandem variable speed configurations Applications beyond traditional HVAC – Water heating systems, commercial boiler replacement, and managing high discharge temperatures for Legionella protection Technician training and tools – Practical advice on learning PWM valves, thermistors, transducers, and system controllers; emphasis on using Copeland Mobile for dynamic performance analysis Market trends and adoption – How vapor injection is becoming standard in premium residential systems and increasingly common across commercial rooftop units and dedicated outdoor air systems Installation and service considerations – Proper system design to avoid oversizing, humidity control in hot-humid climates, and troubleshooting techniques for complex control systems Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

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; they control evaporator feeding and maintain a constant superheat. TXVs achieve this by mechanical means; the bulb responds to suction line temperature and evaporator pressure at the valve. They are self-contained and easy to diagnose with basic refrigeration measurements. However, they are prone to mechanical failures, including clogged orifices and screens, cracked capillary tubes, and powerhead leaks. Installation errors are also easy to make, and TXVs can hunt in low-load conditions. Overall, failures are often mechanical and refrigerant-related. They win in the simplicity department. EEVs receive inputs from sensors and modulate in response to those digital signals. They have a wider modulation range and maintain stable control in low-superheat applications, and they do well in conditions with highly variable loads or where coordination across multiple coils is required. EEVs come in two types: stepper motor (small, discrete steps) and PWM (controlled solenoid valves). Stepper-style EEVs excel at fine positioning, and PWM-style EEVs are in applications that require a more robust valve (like CO2 refrigeration). EEV failures are often electromechanical or related to sensor control. They win in the controllability department. There is no "best" metering device; they merely have different strengths that make them better suited to different applications. However, EEVs are the future due to the greater degree of controllability we will need in newer equipment. Commissioning and airflow are also crucial for getting the most out of both metering device types in terms of longevity and reliability. Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

_*]:min-w-0 !gap-3.5"> In this powerful episode of the HVAC School podcast, Bryan sits down with Nate Agentis, third-generation plumber and author of Get Shit Done: How to Build a Strong Team, A Profitable Business, and a Lasting Legacy. Their conversation explores the intersection of personal health, business success, and meaningful leadership in the trades industry. Nate's journey from technician to business owner wasn't easy. After his grandfather built the family plumbing business from nothing, only to lose it to the IRS, and his father rebuilt it from scratch, Nate found himself thrust into leadership at age 33 when his mother was diagnosed with pancreatic cancer. The tragedy of losing his mother while simultaneously taking over the business created a perfect storm that eventually led to burnout and a period of deep reflection during COVID-19. This experience became the foundation for his leadership philosophy and his book. The conversation delves into the generational divide in the trades, where older workers view younger employees as lazy while younger workers see their elders as slaves to their jobs. Nate argues that healthy leadership requires bridging this gap through understanding and practical solutions. His approach centers on five pillars: healthy owner, sticky culture, skilled technicians, efficient operations, and clear metrics. However, he emphasizes that without the foundation of personal health and self-awareness, the other pillars crumble. Perhaps most compelling is Nate's emphasis on humility and accountability as twin keys to success. He challenges the "self-made man" mentality prevalent in trades culture, arguing that true leadership requires vulnerability, community, and the willingness to seek help. This philosophy extends beyond business into his nonprofit work with Hope for the Trades, which provides educational resources, retreat opportunities, and humanitarian mission trips for tradespeople seeking both professional development and personal renewal. Key Topics Covered Generational Business Transitions - Navigating the challenges of taking over a family business during crisis and the unique pressures of third-generation ownership The Burnout Epidemic in Trades - Understanding why skilled tradespeople burn out and how to create sustainable career paths that don't sacrifice family and personal health Bridging Generational Divides - Addressing the tension between older workers who prioritize work ethic and younger workers who emphasize work-life balance The Five Pillars Framework - Healthy owner, sticky culture, skilled technicians, efficient operations, and clear metrics as the foundation for sustainable business growth Humility and Accountability in Leadership - Why admitting weakness and seeking help are actually signs of strength and keys to long-term success The Balance Wheel Concept - A practical tool for evaluating different areas of life (marriage, parenting, health, spirituality, etc.) and identifying areas needing attention Community and Isolation in Trades - Addressing the epidemic of loneliness among tradespeople and the importance of genuine relationships for personal and professional growth Metrics Without Depression - How to implement business measurement systems as tools for clarity rather than sources of shame or discouragement Hope for the Trades Nonprofit - Educational resources, retreat programs, and humanitarian missions designed to support the whole person, not just the business owner Legacy vs. Profit Mentality - Shifting focus from purely financial success to creating lasting positive impact on employees, families, and communities Practical Life Planning - Applying strategic planning principles to personal life, marriage, and parenting with the same intentionality used in business planning Sign up for Hope for the Trades at https://hopeforthetrades.com/ and get a free copy of Nate's book. You can also order Get Shit Done on Amazon at https://a.co/d/56QyjLQ. Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android

In this episode of the HVAC School podcast, host Bryan sits down with building science expert Allison Bailes to dive deep into the world of Energy Recovery Ventilators (ERVs). The conversation explores the critical role of ventilation in modern homes, highlighting how ERVs have become an essential component of maintaining indoor air quality and energy efficiency. Bailes breaks down the technical nuances of ERVs, explaining how these systems not only bring fresh air into a home but do so while recovering both temperature and moisture energy. The discussion goes beyond simply explaining what an ERV is, delving into the practical considerations of ventilation strategies. Bailes shares personal experiences, including challenges he faced with over-ventilation in his own home, which led to extremely dry indoor conditions. The podcast explores the complex balance of bringing outdoor air inside while managing humidity, temperature, and air quality. Listeners gain insights into why simply bringing in outdoor air isn't always the best solution, especially in climates with extreme humidity or air quality challenges. Throughout the episode, Bailes and Bryan emphasize the importance of thoughtful ventilation design. They discuss the evolution of home construction, noting how increasingly airtight buildings have made proper ventilation more crucial than ever. The conversation touches on key considerations for selecting and implementing ERVs, including motor efficiency, boost capabilities, filtration, and the impact of outdoor air conditions. The experts provide practical advice for contractors, technicians, and homeowners looking to improve their understanding of indoor air management. Key Topics Covered: The difference between Energy Recovery Ventilators (ERVs) and Heat Recovery Ventilators (HRVs) Moisture transfer and vapor permeability in ventilation systems Balanced ventilation strategies and their importance Challenges of over-ventilation and indoor air quality Filtration considerations for ERV systems Impacts of outdoor air quality on home ventilation Strategies for different climate zones The role of ERVs in managing indoor humidity and temperature Resources Mentioned: Allison Bailes' book: "A House Needs to Breathe... Or Does It?" Upcoming online ventilation course from Energy Vanguard (expected May 2025) Energy Vanguard website: energyvanguard.com Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android

In this short podcast episode, Bryan answers a listener-submitted question asking whether you can use another surge protector at the disconnect panel with an ICM 493 already in place. Using multiple surge protectors in the configuration described does NOT count as daisy-chaining. Surge protectors with MOVs (metal oxide varistors) shunt current from high voltage to ground by reducing their resistance. MOVs are sacrificial, so they wear out over time. Surge protectors don't last forever, so installing multiple is a fine idea. You can have whole-home surge protection with additional surge protectors positioned at the appliances/electronics. While it can be done and doesn't hurt anything, it's not the most cost-effective solution. When you install a surge protector, wire it in parallel with the circuit to ground. It should be wired properly with the shortest possible path to ground. In any case, many surge protectors won't hold up against direct lightning strikes, but they will protect the equipment from power surges after power comes back on or constant overvoltage. Our company, Kalos Services, now uses DITEK's Kool Guard 2 as our surge protector and voltage monitor of choice. They also provide warranties for their products, which have come in handy for customers. Learn more about the DITEK Kool Guard 2 at https://www.diteksurgeprotection.com/product-series/intelligent-voltage-monitoring/. Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android

In this podcast episode, HVAC professionals Chris Hughes and Adam Mufich discuss the intricate challenges technicians face when commissioning modern inverter-based heating and cooling systems. Unlike traditional single-stage or two-stage HVAC equipment, inverter systems introduce a new level of complexity that can leave even experienced technicians feeling uncertain about proper installation and startup procedures. The presentation highlights a fundamental shift in how HVAC systems operate, moving from straightforward single-stage systems to sophisticated inverter-based technologies that modulate compressor, fan, and refrigerant flow dynamically. This technological evolution creates significant challenges for technicians, who previously could rely on simple, consistent commissioning processes. The speakers emphasize that modern inverter systems require a much more nuanced approach, with specific temperature ranges, wait times, and verification methods that are not always clearly documented in manufacturer manuals. Recognizing the industry-wide need for clarity, Chris and Adam have developed a comprehensive spreadsheet resource that consolidates commissioning information across multiple HVAC brands. Their goal is to empower technicians by providing accessible, standardized guidance for working with these complex systems. By sharing their research and encouraging collaboration, they aim to address what they see as a critical gap in manufacturer support and technical documentation. The podcast serves as both an educational resource and a call to action for HVAC professionals and manufacturers alike. Chris and Adam argue that the industry needs more transparency, better documentation, and a collective effort to standardize inverter system commissioning practices. Their work represents a significant step towards demystifying these advanced HVAC technologies and ensuring that technicians can confidently and effectively install and service modern heating and cooling equipment. Key Topics Covered: Differences between single-stage, two-stage, and inverter HVAC systems Commissioning challenges with modern inverter technologies Critical factors in proper system startup, including: Outdoor and indoor temperature requirements Wait times for system stabilization Refrigerant charging methods Airflow measurement and verification The importance of precise refrigerant charging (superheat and subcooling) Challenges with manufacturer documentation and technical support The need for standardized commissioning procedures across HVAC brands Strategies for verifying system performance during commissioning The speakers' collaborative effort to create a comprehensive inverter system commissioning guide Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android

In this short podcast episode, Roman Baugh takes over the HVAC School podcast to answer a listener-submitted question about VRF (or VRV) system evacuation. Evacuation is a critical step of making repairs on VRF systems, which are very diverse and versatile but require a high level of understanding. VRF systems have multiple indoor units per outdoor unit, and they achieve that with the help of several components and accessories down the refrigerant line that can pose issues in evacuation and pressure testing. In heat recovery units, some manufacturers use solenoid valves (or even electronic expansion valves) in branch selector boxes or branch collector boxes. These valves act as little traffic guards, and the system needs to be put in its refrigerant recovery or vacuuming mode. If not, then you won't be able to evacuate all of the refrigerant and non-condensables from the system. Even if the system passes a decay test, contamination is a major concern when the system starts up and the valves open (due to nitrogen and oxygen mixing with pure refrigerant being put into the system). You can trust and verify that the system is in its proper operating mode at the thermostat to ensure that the valves are open 100% and ready for evacuation or pressure testing. Failure to do so not only poses a contamination risk but likely won't maintain its pressure during the pressure test. Assumption or trust alone is not enough. Heat pumps only have two lines, and the vacuum pulls from both sides of the valve. There's less of an issue because there are no branch selector or collector boxes, but it's still good to ensure that the valves are responding and communicating. Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android

This podcast episode is of Bryan's session from the HVAC School Symposium, "10 Things I've Learned in the Last 10 Years." Delivered as HVAC School approaches its 10-year milestone and Kalos hits 20 years, Bryan blends technical know-how with personal stories, revealing how his “expertise” is a product of constant learning—often from the very audience he’s addressing. Bryan’s presentation weaves together practical HVAC lessons and relatable anecdotes, offering a glimpse into his growth as a technician, educator, and leader. He tackles wire sizing versus breaker sizing, debunking outdated myths tied to the National Electrical Code and sharing tales of sparring with inspectors over code-compliant innovations. On vent sweating and duct leakage, he provides actionable fixes—like sealing boots and tackling attic moisture—while urging techs to look beyond bandaids. Bryan also dives into coil corrosion, distinguishing formicary from galvanic causes and advocating for field-driven research over manufacturer spin. His interactive style shines as he pauses for audience questions, fostering a dynamic exchange where attendees refine his insights. The talk balances technical depth with human wisdom, spotlighting patience, joy, and consistency as cornerstones of his journey. Bryan recounts Eureka moments—like unraveling why high-latent markets defy evaporator temperature expectations—and credits mentors like Jim Bergmann and peers like Jordan Cummings for sharpening his perspective. He wraps up with a personal touch, addressing work-life balance as a father of 10 and business owner, advocating for mutual sacrifice with family over unilateral trade-offs. Topics Covered: Wire Sizing vs. Breaker Sizing: Debunks NEC myths and shares strategies for navigating inspector challenges. Vent Sweating Solutions: Offers practical fixes like sealing boots and managing attic moisture sources. Evaporator Temperature in High-Latent Markets: Explains unexpected suction pressure behavior with lower airflow. Control Layers in Ducts and Walls: Clarifies roles of vapor, air, and thermal barriers in system design. Formicary vs. Galvanic Corrosion: Differentiates coil leak causes, highlighting VOCs and flux issues. Low-Level CO Monitoring: Stresses its importance for safety in homes with combustion appliances. Duct Leakage: Links leaks to moisture and pressure woes, with visual diagnostic tips. Filtration Importance: Pushes for larger, sealed filters over inadequate factory setups. Compression Ratio and Dehumidification: Explores why ductless/inverter systems falter at moisture removal. Personal Growth and Joy: Ties patience, consistency, and community to a rewarding career. Work-Life Balance: Shares lessons on balancing family and work through shared sacrifice. Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android

In this short podcast episode, Bryan answers a listener-submitted question about using R-290 as a drop-in refrigerant for R-22 systems. It is NOT safe to use R-290 as a drop-in, but there are some similar properties between the two and some interesting thought experiments within this topic. R-290 is propane, a hydrocarbon that belongs to the family of natural refrigerants. R-22 is an HCFC refrigerant that has undergone a manufacturing/importation phaseout in the USA. They are both single-component refrigerants, not blends. Both of them have similar operating pressures and oil carry. However, the latent heat of vaporization of R-290 is almost double that of R-22, which makes it extremely effective as a refrigerant. The main issue with using R-290 is that it is highly flammable and explosive (A3), and it has very small charges (500 grams). Around 2010, some people started selling R-290 blends as drop-in alternatives for R-22. In theory, that combination would work very well, but it is not a safe or legal option. R-290 is currently used in sealed, self-contained equipment. However, it could be the future, especially if our industry goes for refrigerants with lower GWPs and uses flame-free fittings and tubing cutters. It's also worth noting that A2L refrigerants do not contain R-290 or any other hydrocarbons, but it is possible that the industry will gradually embrace the more flammable refrigerants like R-290. Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool. Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android. Subscribe to our YouTube channel. Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android