HVAC School - For Techs, By Techs

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 from exhibitors who don't want to ship anything home. Tony, who spent much of the show working the Fieldpiece booth, shares what it's like to be on that side of the expo floor, while Bryan admits he stopped by the booth but somehow managed to avoid saying hello.

One of the highlights of the episode is a hands-on look at Fieldpiece's brand new analog manifold gauge set — a surprise addition to their lineup. Bryan gives his first impressions live on the mic, noting the heavy-duty build quality, four-port design, dual-scale display for popular refrigerants including R-22, R-32, R-454B, and R-410A, and high-pressure ratings. The standout feature that catches Bryan off-guard is a built-in pressure marker ring — what Tony jokingly calls a "fidget spinner" — that allows techs to mark a pressure point on the gauge dial during standing pressure tests, replacing the old wax pen or Sharpie workaround. Bryan makes a compelling case for why every truck should carry a set of analog gauges as a reliable backup, especially for dirty systems, long-term standing pressure tests, or situations where digital probes or batteries fail.

Tony shifts the conversation to something he's deeply passionate about: Fieldpiece's commitment to tackling two of the biggest challenges facing the HVAC industry today — low-quality workmanship in the field and the growing skills gap as experienced technicians retire. Fieldpiece has launched a formal School Partnership Program, developed after extensive conversations with trade school directors and union leaders to understand their real needs. The program offers in-person support, supplemental training materials focused on best practices, prizes for top graduates, tools for labs and classrooms, and student discounts. Tony also unveils Fieldpiece's mobile training trailer — a fully-equipped 35-foot rig with live HVAC equipment, including a variable-speed heat pump and furnace — designed to bring hands-on training directly to contractors, distributors, and schools. Bryan passionately echoes the importance of repetitive, hands-on practice, arguing that reading books or watching videos will never replace actually pulling vacuums and executing best practices over and over again.

The episode wraps up with Tony sharing details about Fieldpiece's revamped rewards program, where technicians and contractors can earn points by registering products, attending events, and completing free courses on Fieldpiece University — Fieldpiece's online learning platform offering continuing education credits. Bryan encourages small contractors to leverage Fieldpiece University as the backbone of an in-house apprenticeship program without needing a big budget. Tony also teases some exciting future developments, including a new office and learning facility under construction in Heber, Utah, near Park City, a larger state-of-the-art training facility coming to Tustin, California, and a fully redesigned website expected to launch within the next couple of months.

Topics Covered

• Trade show tips: how to score free gear at the end of the last day
• Tony Gonzalez's personal life update
• First look at Fieldpiece's new analog manifold gauge set
• Refrigerant compatibility: R-22, R-32, R-454B, R-410A display on the new gauges
• The built-in pressure marker ring — a clever replacement for the wax pen trick
• Why every HVAC truck should have a set of analog gauges as a backup
• Use cases for analog gauges: dirty systems, long-term standing pressure tests, dead batteries
• Fieldpiece's two-pronged approach to the HVAC industry: reducing low-quality work and closing the skills gap
• The Fieldpiece School Partnership Program — resources, in-person support, student prizes, and lab tools
• Fieldpiece's 35-foot mobile training trailer: bringing live equipment to schools, contractors, and distributors
• The importance of hands-on, repetitive practice for trade skills — not just classroom learning
• Fieldpiece's new and expanded training facilities in Tustin, CA, and Heber, UT
• The revamped Fieldpiece Rewards Program — earning points for swag through product registration, events, and courses
• Fieldpiece University: free online courses with continuing education credit
• How small contractors can use Fieldpiece University to build internal apprenticeship programs
• A shoutout to the GRIT Foundation and their shared mission in workforce development
• Upcoming redesigned fieldpiece.com website
• Tony's trailer driving lessons — and a certain "learning opportunity" involving a sharp turn

Learn more about Fieldpiece's School Partnership Program at https://www.fieldpiece.com/schools/, Fieldpiece University at https://www.fieldpiece.com/fieldpiece-university/, and Fieldpiece's products at https://www.fieldpiece.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 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

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Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

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
• Dehumidification Challenges - Understanding sensible heat factors and humidity control modes
• Building Science Integration - How envelope leakage and infiltration affect inverter performance
• Installation Best Practices - Proper setup, commissioning, and field settings configuration
• Troubleshooting Techniques - Using the diagnostic triangle and understanding EEV operation
• Refrigerant Charging - Advanced methods for verifying proper charge in inverter systems
• Climate-Specific Applications - When inverters thrive vs. when they struggle

Key Topics Covered:

• Why education is the biggest challenge with inverter technology
• The difference between "smart" and "dumb" inverters
• Dehumidification modes: overcooling vs. coil saturation control
• How duct leakage creates a "double whammy" effect
• Rotary vs. scroll compressor technology in inverters
• Mini-split performance data and missing specifications
• Variable capacity adjustments and compressor overclocking
• ERV integration and ventilation strategies
• The importance of building envelope testing

Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

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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. Jesse brings a unique background to the table — from underground coal mining in West Virginia to becoming a lineman, then pivoting to HVAC through vocational school and a contractor-sponsored apprenticeship program. His path to becoming a national trainer is a testament to the value of investing in yourself and being open to learning at every stage of a career.

The core of this episode centers on refrigerant recovery and charging best practices — a topic that might sound routine but quickly reveals how many technicians, even experienced ones, are cutting corners that cost their clients and their companies money. Bryan and Jesse dig into the problems caused by unnecessarily opening sealed systems, the refrigerant lost every time a technician gauges up a system without need, and why the HVAC industry needs to shift its mindset to treat equipment more like a home refrigerator: a sealed system that should run for years without needing to be cracked open. Jesse makes a compelling case that many so-called "mysterious leaks" are actually caused by repeated unnecessary gauge hookups removing small amounts of refrigerant each time.

A significant portion of the conversation focuses on the transition away from manifold gauges toward digital probes and modern recovery setups. Jesse isn't dismissive of manifolds — he acknowledges their place in the classroom and as a backup tool — but he makes a strong case that eliminating restrictions throughout the recovery and charging process is one of the single most impactful things a technician can do to improve efficiency, protect equipment, and deliver better results for customers. Topics like pulling Schrader cores, using 3/8" hoses, Rapid-Y fittings, and the importance of using a filter dryer inline with the recovery machine are all covered with practical, field-tested advice.

Bryan and Jesse also tackle some timely and emerging issues facing the industry, including the equalization behavior of R-454B blends and the growing challenge of refrigerant recovery in extreme cold climates as cold-climate heat pumps become more widespread in northern markets. These aren't hypothetical — they're problems technicians are encountering right now, and Bryan's theory about refrigerant fractionation showing up on thermal imaging cameras offers a genuinely fascinating technical angle. The episode closes with Jesse's overarching message: eliminate restrictions wherever you can, take pride in your craft, and never stop learning.

Topics Covered

• Jesse's background: coal mining, lineman work, HVAC vo-tech, contractor apprenticeship, and path to becoming a national trainer
• The sealed system philosophy: why unnecessarily opening refrigerant circuits causes more problems than it solves
• Manifold gauges — their appropriate role in training and as a backup vs. the case for moving to digital probes
• How repeated gauge hookups can introduce refrigerant loss and fake "mystery leaks" — the 3.5 oz. per hose problem
• Restrictions as the enemy of efficient recovery: pulling Schrader cores, using core removal tools, and proper hose sizing
• The importance of recovering liquid first and how restrictions cause flash gas that slows recovery and adds heat
• Hose size trade-offs: why 3/8" hoses are the recommended sweet spot between flow rate and refrigerant retention
• Using a filter dryer inline with the recovery machine as cheap insurance against acid contamination and machine damage
• Why recovered refrigerant should generally NOT be reused — dirty recovery tanks, fractionation, and the limits of a single filter pass
• Scales as a non-negotiable tool: weighing refrigerant in AND out, and why techs who estimate by feel are guessing
• Diagnosing overcharge and undercharge situations using scale data before making repairs
• Airflow first, charge second: the importance of confirming CFM before adding refrigerant to a struggling system
• The R-454B equalization issue: refrigerant fractionation in new blends and Bryan's thermal imaging theory
• Cold-climate heat pump recovery challenges at sub-zero temperatures and strategies for adding heat to the system
• Heat pump maintenance best practices: testing defrost cycles and what happens when they haven't been checked in years
• Word of mouth as the most powerful (and dangerous) form of advertising in the service industry
• Recovery cylinder safety: the dangers of overfilling tanks and the 80% rule

Learn more about NAVAC's products and resources at https://navacglobal.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 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

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Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

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 science
• How to identify hidden moisture problems in walls and attics
• Combustion safety testing that could save lives
• Understanding dew points and thermal bridging
• Proper ventilation strategies for different climate zones
• Why duct leakage testing is just the beginning

Key Topics Covered:

• Transition from cold climate (Minnesota) to hot/humid (Florida) building science
• Ice dams, ghosting, and crying houses explained
• The house as a system approach for HVAC professionals
• Blower door testing and pressure diagnostics
• Indoor air quality concerns and solutions
• Natural draft appliance safety considerations
• Wall assembly moisture management
• Occupant behavior impacts on building performance

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.

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Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

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 were already studying the effects of low-level CO exposure. One of the most fascinating takeaways from their discussion is just how long the industry has known about the dangers of carbon monoxide, yet how frequently it remains misunderstood, misdiagnosed, and overlooked on the job site.

Louise breaks down the science behind CO poisoning in a way that is both accessible and eye-opening. Unlike high-level acute poisoning — where symptoms are immediately obvious — low-level, chronic carbon monoxide exposure is an entirely different beast. It can mimic the flu, chronic headaches, early-onset Alzheimer's, and even heart attack symptoms. Because CO is colorless, odorless, and tasteless, it is notoriously difficult to diagnose, and victims often have no idea what is causing their illness. Compounding the problem is the cumulative nature of CO toxicity: the gas builds up in the bloodstream over time and can linger in the body for days, months, or even years after exposure ends. Bryan draws an entertaining but sobering historical connection between the prevalence of carbon monoxide poisoning during the Victorian era — when gas lamps were common inside homes — and the widespread reports of ghost sightings, fugue states, fainting spells, and the spiritualist movement of the time. It was almost certainly CO poisoning, not the paranormal.

The conversation then shifts to practical, on-the-job guidance for technicians and contractors. Bryan and Louise walk through the proper process for combustion analysis: starting your analyzer outside in fresh air, identifying test ports on furnaces, boilers, and water heaters, and understanding what readings at steady state actually mean. They emphasize that CO production is not limited to furnaces alone — ranges, ovens, dryers, fireplaces, water heaters, and even propane-powered forklifts are all legitimate sources. One of the most critical points they make is that carbon monoxide hazards are often intermittent and condition-dependent. A system can appear to be working perfectly during one visit and be producing dangerous levels the next time a door is closed or a vent is accidentally blocked. Visual inspection, awareness of combustion air sourcing, and thoughtful analysis are just as important as having the right instruments.

On the product side, Louise introduces two exciting new offerings from UEI. The first is the UEI Clip, a compact personal CO detector that clips onto a bag, belt, or lanyard, activates automatically at 20 ppm, and is designed as a set-it-and-forget-it safety device with a two-year sealed battery lifespan. Priced under $100, it is an affordable way to outfit an entire team with a baseline layer of personal protection. The second highlight is the new High Accuracy Clamp Meter (HAC), a commemorative product celebrating the United States' 250th anniversary. This meter excels at wattage measurement — particularly with low-draw ECM blower motors where most meters fall short — and Bluetooth integration with MeasureQuick is on the horizon. Louise also walks through UEI's revamped combustion analyzer recertification program, UEI Service Plus, which offers same-day turnaround on standard recertifications at their Indianapolis facility, extended warranties with each annual service, and transparent, upfront pricing directly on their website.

Topics Covered

• The history of carbon monoxide research dating back to publications from 1922 and 1923, and a 1923 patent for a hot water heater that sparked a friendly debate between Bryan and Louise about terminology.
• How low-level, chronic CO exposure is underdiagnosed and can mimic conditions like the flu, chronic headaches, early-onset Alzheimer's, and heart attack symptoms — and why CO builds up cumulatively in the bloodstream.
• The fascinating historical theory connecting widespread Victorian-era reports of ghosts, fugue states, and fainting spells to chronic carbon monoxide poisoning from indoor gas lamps.
• CO safety thresholds: residential standard (9 ppm), World Health Organization guideline (4 ppm), first responder evacuation threshold (35 ppm), and how UL-rated home alarms may not trigger until 70 ppm sustained for 1–4 hours.
• Sources of CO that technicians often overlook, including ovens, ranges, dryers, fireplaces, water heaters, propane forklifts, generators, and vehicles idling near garages.
• Proper combustion analysis procedure: starting the analyzer outside in ambient air, identifying or installing test ports, running tests at steady state, and interpreting O2, CO, and stack temperature readings.
• Industry CO standards for furnaces: official standard (400 ppm), HRI recommendation (200 ppm), industry best practice (100 ppm), and modern high-efficiency benchmarks (50 ppm or less).
• How combustion air sourcing — and changes to it (new roofs, blocked vents, swapped doors) — is one of the most commonly missed risk factors for CO production.
• Why even "heat pump markets" like Florida still need combustion analysis, since over 90% of homes have at least one fuel-fired appliance.
• Introduction of the UEi Clip personal CO detector: set-and-forget, activates at 20 ppm, sealed 2-year battery, priced under $100, and its unexpected popularity among refrigeration technicians.
• Introduction of the UEi High Accuracy Clamp Meter (HAC) commemorative edition: exceptional accuracy at low current draws (ideal for ECM blower motors), full accessory kit included, and upcoming measureQuick Bluetooth integration.
• UEi's Service+ combustion analyzer recertification program: same-day turnaround at their Indianapolis lab, extended warranty with each annual service, prepaid UPS shipping labels, and transparent pricing on their website.
• A brief spotlight on UEi as a family-owned business founded by Michael Kane's parents, with their own manufacturing operations in the UK and Korea.

Learn more about UEi's new and longstanding products, as well as the Service+ guarantee, at https://ueitest.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 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

Subscribe to our podcast on your iPhone or Android.

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Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

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 motor comes on. That is a cause of flame rollout and a higher CO measurement.

Induced draft (80%) furnace venting is under negative pressure near the equipment (WRT the air in the room around it). The inducer fan pulls the air through the single heat exchanger, but air isn't "pushed" out of the flue. That's because the draft in the flue is greater than the inducer itself.

80% furnaces are also open-combustion units that pull combustion air in from the air around the furnace, and they require access to fresh air. When you have gaps and cracks in the ductwork, the blower comes on and may cause the combustion analysis readings to change briefly. In a 90%+ sealed combustion furnace, the change is very minimal and doesn't last long; if the numbers vary a lot and are sustained, then that's an indicator of a cracked heat exchanger.

In any case, if you suspect a cracked heat exchanger and want to quote it, you must be able to find it. Proper combustion analysis and combustion analyzer use and care also matter for accurate cracked heat exchanger diagnosis.

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.

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Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

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 coming full circle as the two brands have integrated under the AprilAire umbrella as of January 1st of this year. The episode dives deep into a topic close to both hosts' hearts: how to properly manage indoor humidity, and what role a whole-home ventilating dehumidifier plays in a comprehensive HVAC system strategy.

Bryan and Nikki lay out a holistic framework for tackling moisture problems, emphasizing that a dehumidifier should be the last tool added — not the first. Before reaching for dedicated dehumidification equipment, contractors need to assess the building envelope for air leaks, evaluate whether the air conditioning system is properly sized (oversizing is a major contributor to poor latent removal), confirm that the AC is set up with the right airflow and sensible heat ratio, and take into account the ventilation strategy and occupant behavior. The pair discuss real-world scenarios ranging from elderly residents in Florida who keep their thermostats at 80°F, to a project in Barbados where overcooling caused interstitial condensation in walls and ceilings. The message is clear: humidity control is a systems problem, not a single-product fix.

A significant portion of the episode is dedicated to proper installation practices for whole-home dehumidifiers. Nikki explains why Santa Fe recommends pulling from a dedicated return and discharging into the supply side of the AC duct — rather than tying into the return side — because the heat generated by dehumidification (roughly 1,054 BTUs per pint of water removed) can warm the AC evaporator coil and reduce its latent removal capacity. Bryan adds nuance around dew point management when routing outdoor air ducts, and both hosts agree that fan operation strategy (continuous low-speed vs. intermittent) matters more in tight, low-load homes where mixing is harder to achieve naturally. They also clarify a common misconception: a ventilating dehumidifier is not a dedicated outdoor air system (DOAS) and does not automatically condition incoming ventilation air before it enters the home.

The conversation wraps up with an exciting look at Santa Fe's newly launched Ultra V Series, which features an upgraded 8-inch ventilation duct (up from 6 inches), a more powerful fan for handling higher static pressure in retrofit applications, a new digital control panel, and a wired remote humidity sensor that can be placed in the living space for more accurate readings. Nikki and Bryan also field audience questions on topics like short-cycling risks from oversized dehumidifiers and why Santa Fe chose a wired sensor over wireless (accuracy, reliability, and fewer callback headaches). Bryan closes by noting that rising dew points across most U.S. markets over the last 20 years make whole-home dehumidification more relevant than ever — and that any region where you can see green grass outside is a candidate for a more advanced moisture control strategy.

Topics Covered

• Introduction to Nikki Krueger and the merger of Santa Fe and AprilAire under one brand
• The purpose of whole-home ventilating dehumidifiers and how they fit into an overall HVAC system strategy
• Latent vs. sensible heat loads explained — and why both matter for comfort and moisture control
• Geographic reach of humidity problems — why dehumidification isn't just a Florida or Gulf Coast issue
• Ken Gehring ("Teddy Bear"), inventor of the whole-house ventilating dehumidifier, and his framework for diagnosing moisture problems
• The four-factor checklist before deploying a dehumidifier: building envelope, AC sizing, AC setup/airflow, and ventilation strategy
• How occupant behavior (thermostat preferences, activity levels, large households) creates latent load variability
• The dangers of overcooling — how setting thermostat too low can cause interstitial condensation in walls, ceilings, and attics
• Sensible heat ratio (SHR) and its role in a system's ability to remove moisture — targeting ~350 CFM per ton in humid climates
• Why dehumidifiers should connect to a dedicated return and discharge into the supply — not tie into the AC return side
• How dehumidifier heat output (~1,054 BTUs per pint) can reduce AC coil efficiency when ducted incorrectly
• Fan-on strategy debate: when running continuous low-speed circulation helps vs. hurts humidity control
• Tighter homes, smaller systems, and the importance of air mixing strategies (including ceiling fans)
• Ventilating dehumidifiers vs. dedicated outdoor air systems (DOAS) — clearing up a common misconception about how ventilation air is conditioned
• Dew point management for outdoor air ducts — preventing condensation inside duct runs
• Using dehumidifiers to address sweating ductwork in multi-story homes
• Rising dew points over the past 20 years and what "green grass climates" means for dehumidification demand
• Heat pump oversizing challenges in colder climates and the downstream impact on AC latent removal
• Santa Fe's new Ultra V Series: 8-inch ventilation duct, stronger fan, digital controls, and wired remote humidity sensor
• Why proper dehumidifier sizing matters: short-cycling risks, moisture reservoir release, and uneven RH throughout the home
• Why Santa Fe chose a wired humidity sensor — accuracy, reliability, and reducing contractor callbacks
• Audience Q&A: oversizing consequences, short-cycling mechanics, and sensor placement best practices

Learn more about Santa Fe Dehumidifiers at santafeproducts.com.

Connect with Nikki Krueger on LinkedIn or Instagram @nikkikruegerIAQ.

Check out the work of Ken Gehring ("Teddy Bear") or ask him a question on the HVAC Talk Forum: hvac-talk.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 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 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.

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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.

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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.

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