HVAC School - For Techs, By Techs

In this comprehensive session, Eric Kaiser walks through the critical importance of establishing proper user requirements before making equipment purchases. Drawing from real-world experiences in the HVAC industry, he demonstrates how poor upfront planning leads to costly mistakes, buyer's remorse, and multiple equipment purchases. The discussion covers everything from selecting simple tools like screwdrivers to complex HVAC system installations for residential and commercial applications. Eric begins with relatable examples that everyone can understand - like buying screwdrivers that don't do the job you need them for, leading to accumulating multiple tools over time. He then escalates to more serious scenarios, sharing a story about a company that spent significant money switching business software twice because they failed to identify a crucial missing feature upfront. This pattern of inadequate planning costs businesses and homeowners thousands of dollars and countless hours of frustration. The heart of the presentation focuses on a structured approach to equipment selection that prioritizes needs over wants. Eric introduces a step-by-step process that includes defining intended use, conducting thorough assessments, categorizing requirements as needs versus wants, and performing systematic candidate evaluation. He demonstrates this methodology using electrical meter selection, showing how 38 potential options can be narrowed down to just two viable candidates through careful analysis of features like amperage capability, True RMS measurement, and accuracy requirements. The session expands into HVAC system selection, where the stakes are much higher. Participants share valuable insights about customer expectations, from wanting to know when quiet systems are running (leading to flag solutions on registers) to dealing with customers who expect their new heat pump to feel as warm as their old poorly-designed system. Eric emphasizes that understanding customer expectations often differs from understanding their stated wants, requiring skilled questioning to uncover the real requirements for comfort, noise levels, and operational preferences. Key Topics Covered The Cost of Poor PlanningStructured Selection ProcessNeeds vs. Wants PrioritizationElectrical Meter SelectionHVAC System Selection ComplexitiesCustomer Psychology and ExpectationsCommercial Equipment ConsiderationsInstallation and CommissioningRisk Assessment in SelectionData Collection for Future DecisionsHidden Costs and Considerations 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 explains the science behind a common HVAC simile: static pressure is like blood pressure. He covers the similarities and differences between measuring static pressure during a service call or maintenance and a doctor measuring your blood pressure at a checkup. Total external static pressure (TESP) should be measured every time you perform service or maintenance on a unit. The exact test port location will vary between air handlers and furnaces; the coil adds extra pressure drop in furnace applications. You need to pick a coil that has the lowest static pressure drop (same consideration as filters). Typically, the lower the pressure drop, the better. Make sure you use proper ports for static pressure testing when you do make those holes. Static pressure isn't airflow itself. It can help diagnose airflow issues or give indications, but it doesn't measure the CFM. Static pressure is a balloon-type pressure exerted on the walls of the duct. Just as high blood pressure doesn't mean your heart is pumping more blood than it should, a high static pressure doesn't mean your blower is moving a lot of air; both can indicate restrictions. You also don't want an extremely low static pressure, either. It could indicate that airflow is weak, just like a very low blood pressure indicates that the heart isn't pumping as it should. If you want to know your system airflow, you should use TEC's TrueFlow grid. However, static pressure is particularly good at measuring trends so that you can see where the numbers deviate from the norm for each individual system. 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 comprehensive episode, Bryan Orr sits down with Tim De Stasio to explore the world of comfort consulting and performance contracting in HVAC. Tim, who sold his contracting company to focus on this specialized field, shares his methodical approach to diagnosing home performance issues that go far beyond traditional HVAC troubleshooting. Working primarily in the humid coastal North Carolina market, Tim has developed a thorough process that treats the house as a complete system rather than just focusing on equipment. Tim's journey into comfort consulting began when he recognized the value of comprehensive home performance testing after seeing the work of practitioners like Michael Housh. His approach combines ethical selling with rigorous testing and data collection, allowing him to stand behind his recommendations with confidence. Unlike traditional HVAC service calls that might only involve checking refrigerant levels, Tim's comfort consultations can take an entire day and involve extensive testing protocols that examine everything from building pressure to thermal imaging. The conversation reveals how this type of work requires a fundamental shift in thinking - from being an equipment-focused technician to becoming more like a field engineer or building scientist. Tim emphasizes the importance of having repeatable processes and comprehensive checklists, using tools like Safety Culture app to document findings with photos, notes, and annotations. His methodology starts with a detailed pre-visit questionnaire and includes preparing clients for what will be a very different experience from typical HVAC service calls. Perhaps most importantly, Tim demonstrates how proper diagnostics can lead to ethical sales opportunities. By using tools like blower door tests, thermal imaging, building pressure measurements, and comprehensive system evaluations, he can provide clients with data-driven recommendations prioritized by impact and return on investment. His approach includes a two-week period for analysis before delivering final recommendations, ensuring thoughtful conclusions rather than rushed judgments. Topics Covered The Business Model of Comfort ConsultingPreparing Clients for the ProcessComprehensive Visual AssessmentInterior Documentation ProcessCrawl Space and Attic InspectionsVentilation System TestingBuilding Pressure Testing ProtocolsBlower Door Testing ProceduresThermal Imaging During DepressurizationHVAC System Performance AnalysisIndoor Air Quality MonitoringReport Generation and Client CommunicationTesting Out and Verification 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 talks about non-bleed TXVs and whether they need hard starts. A non-bleed (hard shutoff) TXV is a metering device that shuts off during the off cycle; it closes shut when there is no superheat. This strategy prevents refrigerant migration, especially in cases where we have long line sets. Liquid refrigerant stays in the condenser and is kept out of the evaporator, suction line, and compressor crankcase. When we have a non-bleed TXV, the compressor may have a hard time starting under the conditions created by the hard shutoff TXV (high head pressure, low suction pressure). Reciprocating compressors are more likely to have this problem than a scroll or rotary compressor. If you have a short line set, 230+ voltage, and a scroll compressor, you probably won't need a hard start kit. You may need a hard start kit if you have a reciprocating compressor, a longer line set, or 208V power. The OEM will recommend a hard start kit that is suitable for the equipment. Aftermarket hard start kits are okay if a compressor is old and struggling, but they're not the preferred option and should be as close to the OEM's recommendation as possible. Hard start kits typically consist of a start capacitor and a potential relay. Positive-temperature coefficient resistors (PTCRs) also exist, and these have a resistor that heats up and eventually takes them out of the circuit. Hard start kits should not be added to inverter-driven equipment and are not meant to compensate for voltage drop issues; they can cause more harm than good if they're used when they're not necessary or not used correctly. 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 essential episode, Bryan sits down with Jeff and Tom from Copeland to dive deep into the world of scroll compressors and the critical topic of refrigerant compatibility. As the HVAC industry navigates new refrigerant standards and regulations, understanding how compressors are specifically designed and optimized for different refrigerants has never been more important. The conversation begins with a comprehensive overview of refrigerant classifications, focusing on the A1, A2L, and A3 categories that technicians are encountering in the field. Jeff and Tom dispel common misconceptions, particularly around A2L refrigerants and their relationship to propane (R-290), clarifying that A2L refrigerants like R-454B and R-32 do not contain propane despite widespread confusion in the industry. They explain how regulatory pressures around Global Warming Potential (GWP) limits are driving the transition to these new refrigerants, with targets under 700 GWP for air conditioning applications. The technical discussion covers the fundamental operating principles of scroll compressors and why they've become the dominant technology in HVAC applications. With over 200 million scroll compressors sold by Copeland, the technology has proven its reliability and efficiency. However, the guests emphasize a crucial point that many in the industry overlook: each compressor is specifically optimized for particular refrigerants. This isn't just about basic compatibility – it's about precision engineering to meet efficiency requirements and ensure long-term reliability. The scroll geometry, oil viscosity, and internal components are all carefully matched to each refrigerant's unique properties. Safety takes center stage throughout the discussion, with both guests stressing that while A2L refrigerants are "mildly flammable," they require heightened safety practices that were previously considered best practices but are now mandatory. This includes nitrogen purging during brazing, proper evacuation procedures, comprehensive leak testing, and thorough documentation. The conversation also touches on the practical challenges contractors have faced, including refrigerant availability issues, while maintaining the importance of following proper procedures regardless of supply chain difficulties. Topics Covered: Refrigerant ClassificationsCompressor OptimizationNew Compressor Naming ConventionsOil Viscosity RequirementsSafety ProtocolsGlide CharacteristicsRefrigeration ApplicationsService Compressor StrategyRegulatory TimelineTools and ResourcesTraining Importance Visit the EPA's website to stay up to date on the latest HFC phasedown rulings and information at https://www.epa.gov/climate-hfcs-reduction. Keep up with Copeland at https://www.copeland.com/ and on their Facebook, LinkedIn, and Instagram. 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 explains how leaky ducts can lead to sweaty, uncomfortable houses. Moisture issues are common all across humid and "green-grass" climates in the United States. Hot, unconditioned attics and crawl spaces also often have high dew points, which can cause moisture problems in those spaces. Plants also release moisture, so agricultural communities also have those special considerations. There are several HVAC and building design factors that can prevent or worsen growth from moisture problems. Duct leakage is one of those factors. Return and supply leaks can cause moisture to enter the ductwork. Return leaks suck in air from around the leak. Supply leaks create a pressure differential that can cause mechanically-driven infiltration (MAD-AIR); when a supply duct leak puts the attic under positive pressure, somewhere else has to go under negative pressure. There are lots of gaps and cracks around boots and can lights, which provides pathways for hot, moist air to seep into the envelope. Longer runtimes and keeping the fan on will worsen these conditions. We need to control the source of moisture and then seal the ducts and boots before we focus on the equipment. Visual inspections at the connections and boots will go a long way, but there are also plenty of tools for testing duct leakage, especially by Retrotec and TEC. You can also measure house pressure to the outdoors with the air handler running and all the doors closed, but that's a qualitative measurement that has a lot of other variables to consider. 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 insightful episode of the HVAC School podcast, Bryan Orr sits down with successful small business owner Matt Bruner to discuss how to build and maintain a thriving HVAC business without the typical stress and overwhelming challenges that many entrepreneurs face. Matt, who has been running his own HVAC company for about two and a half years, shares his refreshingly honest perspective on small business ownership and debunks many of the common myths about entrepreneurial stress. Matt's journey from technician to business owner offers a compelling alternative to the traditional "grow fast or fail" mentality that pervades much of the business world. His approach centers on building a business aligned with personal values, particularly the desire to maintain work-life balance while still delivering excellent technical service. Rather than focusing on rapid expansion, fancy equipment, or impressive marketing, Matt chose to start lean, borrow minimal money (only $10,000 from his father for a van down payment), and grow organically while keeping overhead low and stress manageable. The conversation delves deep into the financial discipline required for successful business ownership, emphasizing the critical importance of separating personal and business finances, understanding your true hourly costs, and charging appropriately from day one. Matt candidly discusses his learning curve with business finances, from initially relying on advice from online communities to eventually working with a business coach and reading key books like "Profit First" to truly understand the numbers behind his operation. Both hosts stress that financial literacy isn't optional for business owners—it's a learnable skill that requires dedication but isn't as intimidating as many people believe. Throughout the discussion, both Bryan and Matt emphasize that there's no single "right" way to build a successful contracting business. While some entrepreneurs thrive on rapid growth, multiple locations, and eventual private equity buyouts, others find fulfillment in staying small, maintaining direct customer relationships, and focusing on technical excellence. The key is knowing yourself, understanding your values, and building a business structure that supports your personal and professional goals rather than chasing someone else's definition of success. Topics Covered Personality traits that support successful small business ownershipFinancial discipline and money managementStarting lean and avoiding debtThe learning curve of business financesWork-life balance in business ownershipChoosing your business modelTechnical work vs. business managementPricing strategies and customer relationshipsCommon mistakes to avoidBuilding systems and staying organizedPartnership considerationsLong-term sustainability 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 business and building-oriented short podcast episode, Bryan discusses the limitations and downsides of intentionality. He also talks about the differences between people who act, think, and work quickly and those who are a bit slower, more detailed, and more methodical; there are upsides and downsides to both. People often talk about being intentional, but those intentions have little impact on the world unless they lead to action. Intentionality feels productive, but it doesn't make a difference unless the execution piece is also there. Likewise, skills come from action, not aspiration. Books and podcasts are tools that support efforts to improve, but you can't improve skills without practicing. There is also the career paradox: we expect people, especially kids, to know what they want to do when they grow up. Their answers aren't backed by any real-life experience. People do the same as adults; we expect them to know what they truly want to do when they haven't necessarily been challenged (or physically made something real or fixed something with their hands). In many of these cases, opportunism and trying new things out, even if it means messing up or being criticized, are more important than intentionality. It helps to think of opportunism in terms of "hat" decisions, "hairstyle" decisions, and "tattoo" decisions. "Hat" decisions are things you can try out without consequences; be opportunistic. "Hairstyle" decisions have longer-lasting effects and require a bit more intentionality, but it's still good to make some of these decisions. "Tattoo" decisions have lasting effects and require intentionality. Intentionality is most useful when we have the experience already; act first and reflect later. 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 fascinating episode, Bryan welcomes back longtime friend and nuclear industry veteran Bill Nowicki to discuss a recently released document from DHS and NUSTL that provides new recommendations for HVAC operations during nuclear events. Bill brings over 40 years of nuclear experience, starting as a 19-year-old Navy nuclear operator (after being deemed "not ready for the grill" at Friendly's restaurant) and progressing through various roles, including lead engineer on critical control systems at nuclear facilities. Bill shares his journey from nuclear plant evaluator to leadership trainer, now working internationally to help nuclear professionals develop their skills. His current podcast, "The Nuclear Leader," continues this mission alongside his passion project, "Navigating Mental Illness: Parent Stories." Bill provides an accessible explanation of nuclear reactor operations, using the analogy that "contamination is the poop and radiation is the smell" to help listeners understand the difference between radioactive material and radiation itself. He walks through the three-barrier system in nuclear plants: fuel cladding, reactor coolant system, and containment structures. The discussion covers how fission works, the controlled chain reaction process, and what happens when these systems fail, using examples from Three Mile Island, Chernobyl, and Fukushima to illustrate different failure modes. The episode explores the current nuclear renaissance driven by AI data centers and industrial companies seeking clean baseload power. Bill explains how private industry is now directly funding nuclear projects, bypassing traditional utility structures, with companies like Microsoft and ExxonMobil investing billions in new nuclear facilities. This represents a dramatic shift from the post-Three Mile Island era when nuclear construction essentially stopped in the United States. The core discussion focuses on updated emergency guidance that reverses previous recommendations. Instead of the old "shelter in place and shut off your AC" advice, the new guidance suggests keeping HVAC systems running while eliminating outdoor air intake. This approach recognizes that modern, well-sealed buildings with high-efficiency filtration can provide better protection by maintaining positive pressure and filtering recirculated air rather than allowing uncontrolled infiltration. Bill and Bryan discuss how building characteristics dramatically affect the best response strategy. High-performance homes with tight construction, MERV 13+ filters, and controlled ventilation systems offer significant advantages, requiring only the ability to shut off outdoor air intake. Conversely, older, leaky buildings may still benefit from complete system shutdown to prevent contamination circulation. The conversation highlights how lessons learned during COVID-19 about airborne contamination and filtration directly apply to nuclear emergency preparedness, emphasizing the importance of case-by-case analysis rather than one-size-fits-all approaches. Topics Covered Nuclear industry career pathsBasic nuclear physicsNuclear plant safety systemsCurrent nuclear renaissanceEmergency preparedness evolutionBuilding performance factorsHVAC system modificationsCase-by-case response strategiesPodcasting journeyLeadership developmentPersonal stories Here is the full document from the DHS: https://www.nrc.gov/docs/ML2425/ML24250A059.pdf 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 about a bigger-picture topic, Bryan talks about making stuff real. He talks about how to make ideas, businesses, podcasts, and other large projects come to life based on his experiences with HVAC School, Kalos, and several other current and past projects. Understanding yourself and the thing you want to do is the first key to making things real. You need to be able to speak intelligently about a topic (without sounding pretentious); mastery isn't always the goal, but you need to have some level of understanding of the general topic and your own strengths and weaknesses. Starting a business requires you to acquire at least a working knowledge of software, compliance, insurance, licenses, and other items related to that particular business. You also want to avoid relying solely on someone else's vision or advice for your project. Then, curiosity and exploration are key; you need to get practice and immerse yourself in the work to get an understanding of the process and your strengths and weaknesses. It's okay if your work doesn't look good; you just need experience, not affirmation, early on. Hiring good people also matters; these people don't need to be perfect, but they need to be growth-oriented and reliable. You'll also likely work with people who are poor fits before finding the right person for your business or project. When you have the right people on your team, you need to be consistent, communicate clearly, pay well and on time, and provide plenty of meaningful work. 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 comprehensive discussion, Bryan sits down with Brad Cooper, an experienced HVAC instructor from Arkansas, and JD Kelly, a trade school graduate, to tackle one of the most pressing questions in the HVAC industry: Is trade school worth it? Rather than offering a simple yes or no answer, the trio dives deep into the nuanced factors that determine whether trade school provides real value for aspiring HVAC technicians. The conversation begins with Brad's unique perspective as both a field technician with over 20 years of experience and a current instructor who transitioned to teaching five years ago. His father's business background and the common frustration of having to "go behind people and fix stuff" motivated Brad to enter education, believing that proper training from the start could eliminate many field problems. JD brings the student perspective, having attended trade school while working full-time, which gives him insight into both the challenges and benefits of formal HVAC education. A significant portion of the discussion focuses on what to look for when evaluating trade schools. The guests emphasize that the investment in laboratory equipment and facilities often reflects the school's commitment to the program - you can tell immediately upon walking into a lab whether the institution truly prioritizes HVAC education. They stress the importance of accreditation, particularly from organizations like HVAC Excellence, which provides regular oversight and ensures schools meet industry standards. The conversation reveals that accreditation isn't just about having a certificate on the wall; it represents a school's willingness to submit to external scrutiny and maintain educational quality. The discussion also addresses the critical balance between theoretical knowledge and practical application. All three speakers agree that the most valuable trade school experiences combine classroom learning with real-world field exposure through partnerships with local contractors, apprenticeship programs, or internship opportunities. They emphasize that instructor quality matters more than having the latest equipment - a humble, field-experienced teacher who can adapt to different student skill levels and learning styles proves far more valuable than someone with extensive theoretical knowledge but limited practical experience. Topics Covered School Evaluation CriteriaInstructor QualificationsProgram Length and StructureHands-On LearningStudent Readiness and ExpectationsIndustry Connections 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 split-phase and 3-phase power in HVAC systems. Split-phase is a form of single-phase power, and it's common in residential HVAC. Three-phase power is more common in commercial and industrial applications. Single-phase power uses only one of the three phases of power produced by the power company. When there is a neutral and two sides of 120V power, that is split-phase power. Transformers on power poles for residential service only have one line going into them (and only one sine wave). That power gets stepped down to ~240V. Most household appliances and electronics we use are rated for 120V or 240V power. However, we use split-phase power by tapping the center of the transformer secondary; there are two 120V halves. We can see the "differences" between split-phase and single-phase power with an oscilloscope. These halves may look like two different sine waves if we use neutral as a reference, but an oscilloscope will only show one 240V sine wave from leg to leg (without neutral). Therefore, split-phase power really is just single-phase power with a center reference point, and split-phase power doesn't matter to the HVAC unit. We get three-phase power when all three phases of power come in from the utility, not just one. Each individual phase is 120V, and all three can make up 208V power because the phases are 120 degrees out of phase. 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 from the 6th Annual HVACR Training Symposium, Brynn Cooksey, a home performance contractor from Michigan and technical training business owner, reveals how indoor air quality (IAQ) testing transformed his contracting business from a commodity service into a profitable specialty. Cooksey shares his proven methodology for turning IAQ into an "instant profit center" by implementing systematic testing on every service call. Cooksey opens with a striking reality check: according to the EPA, Americans spend 90% of their time indoors, yet indoor air quality is 2-5 times worse than outdoor air. This presents a massive opportunity for HVAC contractors, as he explains that consumers are already spending $10 billion annually on air quality products at big box stores - but they're treating symptoms rather than addressing root causes. His approach involves educating contractors on how to position themselves as the solution providers rather than letting customers self-diagnose with retail products. The presentation dives deep into six critical IAQ parameters that every contractor should measure: particles (especially dangerous PM 2.5), volatile organic compounds (VOCs), carbon dioxide, carbon monoxide, humidity, and temperature. Cooksey emphasizes his "test in, implement solution, test out" methodology, demonstrating how this systematic approach not only ensures customer satisfaction but also provides concrete proof of value delivered. He shares real-world examples, including a dramatic case where routine IAQ testing during a water heater service call revealed a cracked heat exchanger that could have been life-threatening. The episode concludes with extensive coverage of ventilation strategies, which Cooksey calls the "silver bullet" for IAQ improvement. He walks through the differences between supply-only, exhaust-only, and balanced ventilation systems, strongly advocating for Energy Recovery Ventilators (ERVs) as the optimal solution. His practical approach includes using DOE's free REDCalc tool for proper ventilation sizing and emphasizes the importance of controlled ventilation over relying on natural air leakage - debunking the myth that "houses need to breathe." Topics Covered The IAQ Business CaseSix Critical IAQ ParametersSystematic Testing MethodologyParticle Control StrategiesChemical and VOC ManagementCarbon Monoxide DetectionVentilation as the Silver BulletPractical Implementation ToolsReal-World Case StudiesBuilding Science Integration 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 covers some basics on bi-metal and magnetic switches. Bi-metal switches are made of two dissimilar metals that are bonded together and are often integrated into motors. When the temperature changes, the metals bend. In an overload circuit, they're designed to bend and open the circuit in an overheat condition. Mercury thermostats also use these; they have a bulb attached to a bi-metallic coil, which causes it to wind or unwind when heated or cooled. Fan limit switches also use bi-metallic coils. Bi-metallic discs also exist, and they snap open to make or break a circuit. Bi-metallic switches have a time delay and often auto-reset (with exceptions like rollout switches on furnaces), which is advantageous in some applications. However, they're also affected by the ambient temperature and are more likely to trip in warm weather and less likely to trip in cold weather. Nuisance trips are more common than in magnetic switches, and they may weld themselves shut and fail closed (though failing open is relatively common as well). Magnetic switches are usually more external to the equipment or parts they're protecting (such as in the contactor or starter assembly instead of inside a motor itself). These switches are also more instantaneous and are better for mission-critical applications. These also respond to amperage and aren't affected by ambient temperature. They're more likely to fail open than closed. Compared to bi-metallic technology, magnetic switches trip faster and are better for sudden issues rather than long-term operational overheating. In many cases, we use both of them to get the benefits of each. 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 educational session, Adam from National Comfort Institute (NCI) delivers a comprehensive deep dive into Fan Law 2 and its practical applications for residential HVAC systems at the 6th Annual HVACR Training Symposium. Adam begins by establishing the fundamental concepts of CFM (cubic feet per minute) and static pressure, explaining how these measurements relate to system performance. He shares a humbling personal story about learning to measure gas pressure from a homeowner, emphasizing that even experienced technicians can benefit from understanding basic measurement principles. The presentation focuses heavily on Fan Law 2, which allows technicians to predict how changes in airflow will affect static pressure in a non-proportional relationship - a critical concept for equipment sizing and replacement decisions. The core of the presentation revolves around practical applications of Fan Law 2 in real-world scenarios. Adam demonstrates how to calculate pressure drops across filters, evaporator coils, and entire duct systems when airflow changes occur. He emphasizes that static pressure increases exponentially when airflow increases, which explains why oversized systems often perform poorly. Through detailed examples using actual field measurements, he shows how a 16% increase in airflow can result in a 33% increase in static pressure, highlighting the importance of proper system sizing. Perhaps most importantly, Adam presents a systematic approach to equipment selection that goes beyond simply matching tonnage. He demonstrates how contractors can "back into" total external static pressure calculations by carefully selecting low-pressure-drop components like evaporator coils and filters. This methodology allows technicians to predict system performance before installation, preventing the common scenario where new equipment sounds "like a rocket ship" due to excessive static pressure. The presentation concludes with a compelling comparison showing how proper component selection can reduce system static pressure from over 1.0 inches to 0.64 inches while maintaining the same capacity and airflow. Topics Covered Static Pressure FundamentalsFan Law 2 MathematicsPractical ApplicationsEquipment Selection StrategyReal-World Problem SolvingProfessional Development 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 drops some knowledge to help with understanding voltage drop, a few different causes of it, and NEC recommendations. Voltage is electrical potential or "pressure," and voltage drop is the reduction in electrical potential energy. We often think of it happening across conductors (which add resistance), but it also happens across loads (like contactor coils). Voltage drop across loads is usually designed, but voltage drop across conductors is usually undesigned and undesirable. Several factors contribute to conductor resistance. Length is a major one; long runs of wire introduce more resistance to the circuit than shorter runs. Size/gauge also matters; smaller-gauge wire has more resistance than larger-gauge wire. Copper is the most common material for wiring, but we use other materials (including steel or aluminum), and those have different resistance values. Temperature also affects resistance, as they both increase and decrease as the other one does. When we measure voltage drop, we want to make sure we're doing it under load, NOT on startup. Voltage drops that happen on startup can be mitigated with more suitable infrastructure (including larger wires) or soft starts. Undersized conductors don't have sufficient cross-sectional area for the applied load. To avoid voltage drop due to undersized conductors, we should size conductors based on minimum circuit ampacity (MCA), not breaker size (MOCP). Poor connections can also cause resistance to jump, which reduces voltage; we need to pay attention to the connection design (including torque specs and proper lugging) to avoid making mistakes. Long wires don't cause overheating by themselves, but they still contribute to voltage drop and cause reduced performance (including drawing higher current on startup). 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 enlightening presentation, Alex Meaney breaks down the fundamental concepts of airflow in HVAC systems using practical analogies and real-world examples. Rather than diving straight into complex mathematics, Alex focuses on helping technicians and contractors understand what's actually happening inside ductwork and why traditional design methods may be falling short in modern residential systems. Alex begins by addressing one of the most critical yet misunderstood aspects of ductwork: the exponential relationship between duct size and airflow capacity. He explains that the difference between a 6-inch and 7-inch duct isn't just 17% more capacity—it's actually 36% more, because airflow is determined by cross-sectional area (which increases geometrically) rather than linear measurements. This fundamental misunderstanding leads to significant underperformance in many HVAC installations. The presentation tackles the confusion surrounding pressure terminology in the HVAC industry, where the single word "pressure" is used to describe four distinct concepts: static pressure, velocity pressure, pressure loss, and external static pressure. Alex uses creative analogies, including a memorable demonstration with an inflatable tube dancer (referencing the "used car lot" in his title), to illustrate how static pressure and velocity pressure are always in balance—when one increases, the other decreases proportionally. A major focus of the discussion centers on why the traditional 0.1 inches of water column per 100 feet friction rate, long considered standard in residential duct design, is no longer adequate for modern systems. Alex explains that today's homes have evolved significantly: they're larger, use more restrictive filters for air quality, have more complex coil designs, and often place equipment in suboptimal locations. These factors combine to create much higher system resistance than the 0.1 standard was designed to handle. He advocates for using lower friction rates (like 0.06) and emphasizes that proper duct sizing is more critical than ever. The presentation concludes with practical insights about system design philosophy, emphasizing that while homeowners may not complain about poorly performing systems, HVAC professionals should use objective measurement tools rather than customer satisfaction as the primary indicator of system performance. Alex stresses that craftsmen in the field will make systems work regardless of design flaws, but this shouldn't excuse poor initial design practices. Key Topics Covered Duct Sizing FundamentalsPressure Concepts DemystifiedFriction and Resistance in DuctworkModern System Design ChallengesMeasurement and Verification MethodsPractical Design Philosophy 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, Bryan Orr sits down with Adam and Matt to tackle one of the most misunderstood aspects of HVAC system design: return air systems. The conversation dives deep into the common myths surrounding returns, particularly the widespread belief that adding returns to rooms will automatically improve comfort and air mixing. The hosts explore why returns are often seen as mysterious - sometimes helping when added to a room, sometimes making things worse - and work to clarify the actual science behind how returns function versus how many technicians think they work. The discussion reveals a fundamental misunderstanding in the industry about the difference between supply and return air behavior. While supply air creates significant mixing effects through entrainment and the Coanda effect, returns have a much more limited impact on room air patterns. According to Manual T, laboratory tests show that return air intake influence is limited to just a few feet around the grille, even at high velocities. This leads to the key insight that returns serve primarily as pressure relief mechanisms rather than air mixing devices, which explains why their placement and sizing strategies differ significantly from supply air design principles. The hosts examine real-world scenarios, including Matt's experience with a two-story home where the homeowner requested an additional return on the second floor despite having adequate return pathways. They discuss the Manual D recommendation for returns on each floor while sharing field experiences where single central returns have successfully maintained temperature differentials within two degrees across multiple floors. The conversation emphasizes that proper system design, including accurate load calculations and right-sized equipment, often eliminates the need for complex return strategies. A significant portion of the discussion focuses on the practical considerations of passive versus active returns. The hosts lean toward passive return strategies (transfer grilles, jumper ducts, and door undercuts) for their simplicity, cost-effectiveness, and reduced ductwork requirements. However, they acknowledge the challenges of proper sizing - passive returns must be significantly larger than their active counterparts since they rely on minimal pressure differentials rather than mechanical assistance. The conversation also addresses privacy concerns with transfer grilles and the benefits of oversized jumper ducts for noise attenuation. Key Topics Covered Common Return Myths DebunkedPressure Relief vs. Air MixingManual D Guidelines and Field RealityPassive Return StrategiesSystem Design FundamentalsZoning ConsiderationsPractical Installation TipsAdvanced Concepts 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

If you're a fan of fans, this is the podcast for you! In this short podcast episode, Bryan shares how installing ceiling fans can be a smart HVAC design strategy (even though he wasn't a fan of fans!). Ceiling fans break the "don't blow air on people" rule we usually refer to in duct design, but they can solve quite a few basic comfort problems, especially in homes with lower loads than we've historically seen. They're great for creating high-velocity airstreams and mixing air. Low-load homes have systems with lower tonnages; they don't move as much air and could use a little bit of help from a ceiling fan. Air mixing is also poor in homes that have a greater distance between the air and the ceiling. Stratification of the air causes comfort problems due to temperature differences, and hot or cold surfaces can also contribute to these issues for similar reasons. Moisture and eventual growth are also concerns when we allow rooms to have those temperature differences (especially on the ceiling, as water vapor is lighter than air). Ceiling fans disrupt the stratification of air and water vapor. They solve air mixing problems while they dispel odors and maintain more consistent dew points throughout the air. Modern fans with ECMs can also run at a low speed without taking a large energy efficiency hit. Ceiling fans are great and relatively inexpensive solutions that can solve comfort and IAQ problems in high-performance homes. 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, Bryan Orr sits down with Roman Baugh, a leading VRF (Variable Refrigerant Flow) specialist and co-host of the VRF Tech Talk podcast, for an in-depth exploration of VRF system maintenance. The conversation begins with some lighthearted back-and-forth before shifting to the technical realities of maintaining VRF equipment. Roman immediately addresses a common misconception: the idea that VRF systems are “maintenance free.” He explains that, contrary to some marketing claims, these systems require regular, specialized attention to ensure longevity and reliable performance. Roman shares real-world stories that highlight the consequences of poor installation and lack of serviceability. He describes situations where VRF units are installed in hard-to-reach locations—like cabinets or hard-lid ceilings—making even basic maintenance a costly and invasive process. This lack of foresight often leads to significant expenses for property owners, especially when major repairs require extensive drywall work just to access failed components. Roman emphasizes that proper maintenance starts with ensuring that systems are accessible and serviceable, a step too often neglected during installation. The discussion delves into the specifics of VRF maintenance, moving beyond the basics of filters and drain lines. Roman explains how improper drain line installation can lead to persistent error codes and system shutdowns, particularly when condensate pumps are forced to exceed their design limitations. He goes on to detail the critical role of temperature sensors (thermistors), which are prone to failure from corrosion, moisture, and environmental factors—especially in challenging locations like laundry rooms. These sensor failures can cause misleading error codes and even compressor damage if not addressed promptly. Roman recommends regular sensor checks, especially as components age past their typical five-year lifespan. A significant portion of the episode is dedicated to electronic expansion valves (EEVs), which are susceptible to rust, dried grease, and mechanical binding. Roman advocates for proactive inspection and, when necessary, preemptive replacement of EEVs to prevent catastrophic compressor failures. He introduces tools developed by technicians for technicians, such as the EEV Mate and custom EEV magnets, which allow for manual manipulation and diagnostics of expansion valves in the field. These innovations help HVAC professionals quickly triage and resolve issues, minimizing downtime and protecting expensive system components. The episode wraps up with a strong endorsement for ongoing education, technician communities, and the use of specialized tools and software to ensure VRF systems are maintained to the highest standard. Topics Covered: Debunking the “maintenance-free” VRF myth Access and serviceability challenges in VRF installations Proper drain line design, installation, and common failure points The role and failure modes of temperature sensors (thermistors) Environmental impacts on sensor and component reliability Electronic expansion valve (EEV) maintenance and troubleshooting Field-developed tools for EEV diagnostics (EEV Mate, EEV magnets) The importance of commissioning and using service software Application and installation quality as a foundation for long-term reliability Technician communities, podcasts, and resources for VRF learning and support This episode is essential listening for HVAC professionals seeking to deepen their understanding of VRF systems, avoid common pitfalls, and stay ahead with practical, field-tested maintenance strategies. For more insights, check out Roman Baugh’s VRF Tech Talk podcast and YouTube channel for additional resources on VRF technology and troubleshooting. Check out the VRF Tech Talk podcast on YouTube HERE, or search for it on your favorite podcast app. Have a question that you want us to answer on the podcast? Submit your...