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.

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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 Criteria
  • Laboratory equipment quality and investment levels
  • Accreditation importance (particularly HVAC Excellence)
  • Modern tools vs. traditional equipment balance
  • Manufacturer partnerships and industry connections
• Instructor Qualifications
  • Field experience vs. teaching credentials
  • Importance of humility and adaptability
  • Managing diverse skill levels in the classroom
  • Storytelling and practical application methods
• Program Length and Structure
  • Comparison of certificate programs vs. associate degrees
  • Benefits of two-year programs for comprehensive learning
  • Integration of on-the-job training and apprenticeships
  • Realistic expectations for different program lengths
• Hands-On Learning
  • Importance of repetition and practical experience
  • Managing consumable materials and budget constraints
  • Real-world equipment exposure vs. lab simulations
  • Peer mentoring and collaborative learning approaches
• Student Readiness and Expectations
  • Managing diverse student backgrounds and skill levels
  • Realistic employer expectations for graduates
  • The value of combining school with field experience
  • Personal responsibility in education and continuous learning
• Industry Connections
  • Importance of school-contractor partnerships
  • Field trip opportunities and manufacturer relationships
  • Bridging the gap between classroom and real-world application
  • The role of apprenticeships in comprehensive training

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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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.

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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 Case: How testing indoor air quality on every service call creates new revenue streams and differentiates contractors in a commoditized market
• Six Critical IAQ Parameters: Detailed explanation of particles (PM 2.5), VOCs, carbon dioxide, carbon monoxide, humidity, and temperature - what they are, how to measure them, and health impacts
• Systematic Testing Methodology: The "test in, implement solution, test out" approach that provides measurable results and customer proof of value
• Particle Control Strategies: Source control, enhanced filtration (MERV 13-16), duct cleaning benefits, and duct sealing with Aeroseal technology
• Chemical and VOC Management: Understanding formaldehyde and benzene sources, proper storage techniques, and why PCO devices aren't recommended
• Carbon Monoxide Detection: The life-saving importance of testing every home, understanding chronic vs. acute exposure, and why standard CO detectors aren't sufficient
• Ventilation as the Silver Bullet: Comprehensive coverage of supply-only, exhaust-only, and balanced ventilation strategies, with strong emphasis on ERV systems
• Practical Implementation Tools: Using DOE's REDCalc tool for ventilation sizing, integrating IAQ testing into service calls, and customer communication strategies
• Real-World Case Studies: Multiple examples of IAQ testing uncovering dangerous conditions, from cracked heat exchangers to improper combustion appliance installation
• Building Science Integration: How IAQ testing leads to broader building performance improvements, including duct sealing, insulation, and equipment sizing corrections

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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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.

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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 Fundamentals
  • Definition and measurement using manometers
  • Inches of water column explained
  • Relationship between static pressure and system performance
• Fan Law 2 Mathematics
  • Breaking down the intimidating formula into simple terms
  • Step-by-step calculation examples
  • Common mistakes when squaring numbers in calculations
• Practical Applications
  • Filter pressure drop calculations at different airflows
  • Evaporator coil pressure drop analysis
  • Total External Static Pressure (TESP) predictions
  • Duct system pressure calculations
• Equipment Selection Strategy
  • How to select evaporator coils based on pressure drop ratings
  • Filter sizing for optimal pressure drop
  • Using manufacturer data sheets effectively
  • AHRI matchup considerations beyond just capacity
• Real-World Problem Solving
  • Preventing "rocket ship" installations
  • Retrofitting existing systems with proper calculations
  • Downsizing benefits for static pressure reduction
  • System commissioning and performance verification
• Professional Development
  • Moving beyond equipment replacement guesswork
  • Using measurement tools like True Flow Grid
  • Understanding manufacturer specifications
  • Elevating installation quality through proper system design

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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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.

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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 Fundamentals
  • The geometric relationship between duct diameter and airflow capacity
  • Why linear measurements can be misleading when calculating system performance
  • The critical importance of proper duct sizing in modern installations
• Pressure Concepts Demystified
  • Static pressure vs. velocity pressure and their inverse relationship
  • How pressure and friction work together in ductwork systems
  • External static pressure as a measure of fan capability
  • The role of pressure in airflow generation and control
• Friction and Resistance in Ductwork
  • Understanding friction as the primary enemy of airflow
  • How fittings create equivalent lengths of straight duct
  • The impact of direction changes and system components on airflow
  • Comparing flex duct vs. metal duct friction characteristics
• Modern System Design Challenges
  • Why traditional 0.1 friction rates no longer work effectively
  • The evolution of residential systems: larger homes, better filters, complex coils
  • Equipment placement strategies and their impact on system performance
  • The "war on sensible" and "war on blowers" affecting modern HVAC design
• Measurement and Verification Methods
  • Tools for measuring static pressure and velocity pressure
  • The importance of using objective measurement tools over customer satisfaction
  • Available static pressure calculations and their practical applications
  • Manual D design principles and their real-world limitations
• Practical Design Philosophy
  • Working backwards from blower capacity rather than arbitrary friction rates
  • Balancing system performance with budget constraints
  • The importance of central equipment placement for optimal airflow
  • Professional standards vs. "good enough" mentality in system design

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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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 Debunked
  • The belief that adding returns automatically improves room comfort
  • Misconceptions about returns mixing air effectively
  • The difference between supply air entrainment and return air influence
• Pressure Relief vs. Air Mixing
  • Returns function primarily for pressure balancing, not air circulation
  • How to measure pressure problems using flow hoods and micromanometers
  • The impact of door closure on supply air delivery
• Manual D Guidelines and Field Reality
  • Manual D recommendations for returns on each floor
  • Real-world examples of successful single central return systems
  • When to follow guidelines versus when field conditions allow flexibility
• Passive Return Strategies
  • Transfer grilles, jumper ducts, and door undercuts as alternatives to active returns
  • Proper sizing considerations for low-resistance return pathways
  • Privacy and noise concerns with different passive return methods
• System Design Fundamentals
  • The importance of accurate load calculations in reducing return requirements
  • How right-sizing equipment reduces airflow and pressure management challenges
  • The relationship between static pressure and airflow changes
• Zoning Considerations
  • Whether to add dampers to returns in zoned systems
  • Potential depressurization issues when zones are closed
  • Passive solutions for zoned system return air management
• Practical Installation Tips
  • Avoiding short-cycling by maintaining proper supply-to-return distances
  • The risks of undersized return pathways
  • Balancing damper selection and sealing strategies
• Advanced Concepts
  • Destratification strategies using ceiling fans versus high returns
  • The impact of conditioned versus unconditioned return air pathways
  • Energy efficiency considerations in return system design

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

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