Absorption Cooling - The Rise and Fall and Rise - Short #272
HVAC School - For Techs, By Techs
In this short podcast episode, Bryan goes on another history journey, retelling the story of the rise and fall and rise of absorption cooling. Some of the first HVAC/R engineers cooled buildings with fire; they used absorption refrigeration, which ran on heat instead of electricity. In the early 1800s, French scientist Michael Faraday showed that gases like ammonia could absorb heat as they evaporated. Instead of compressing the vapor, engineers looked for a way to absorb the heat from the vapor and drive it back out. In 1859, Ferdinand Carré invented a machine that boiled ammonia,...
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Combustion Analysis w/ Tony G.
HVAC School - For Techs, By Techs
In this comprehensive training session from the symposium, Tony Gonzalez, Training Director at Fieldpiece, delivers an engaging and practical guide to combustion analysis for HVAC technicians. With 25 years of experience at Fieldpiece—from warehouse worker to training director—Tony brings both technical expertise and real-world application to this 50-minute interactive session focused on the company's CAT 85 combustion analyzer. Tony emphasizes that combustion analysis serves four critical purposes: safety, efficiency, equipment specification verification, and liability protection. He...
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Give Until it Hertz - The Battle Over Frequency - Short #271
HVAC School - For Techs, By Techs
In this short podcast episode, we go back into the history of the trades, namely the battle over frequency (and how each side had to give until it hertz). The low hum of motors is alternating current: electricity moving back and forth through copper 60x per second (in the USA and Canada, at least). In another version of history, that pulse could be 50x per second instead (as in much of the remainder of the world). The forgotten frequency war is the lesser-known sequel to the war of the currents. Tesla's AC power prevailed over Edison's DC, but different motor and generator companies chose...
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Residential vs. Commercial HVAC Sales
HVAC School - For Techs, By Techs
In this candid conversation, Nathan and Bryan dive deep into the often-misunderstood world of sales in the construction and HVAC trades. Nathan, who has transitioned from fieldwork to spending roughly 60% of his time in sales, offers a unique perspective on why sales professionals are necessary despite the skepticism they face from tradespeople. The discussion tackles head-on the negative perceptions surrounding salespeople while making a compelling case for their essential role in growing and sustaining a trades business. The conversation explores the fundamental differences between...
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When Ammonia Ruled the World - Short #270
HVAC School - For Techs, By Techs
In this short podcast episode, Bryan takes us on a history journey back to when ammonia ruled the world. In the mid-1800s, before R-12, many inventors and scientists experimented with vapor-compression refrigeration systems to make ice. They used a variety of refrigerants in their patents, including ether, ethyl ether, carbon dioxide, sulfur dioxide, methyl chloride, and ammonia. Each one had tradeoffs, but ammonia was the favorite because it was inexpensive, very good at moving heat, and useful because its odor made leaks obvious (although it was toxic and irritated the lungs and mucus...
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Humidity, Airflow, and Refrigeration
HVAC School - For Techs, By Techs
In this episode of the HVAC School podcast, Bryan and Nathan dive deep into the challenges of humidity control in grocery stores and other refrigerated environments. While the conversation takes several entertaining detours (including discussions about morning radio shows, Indian weddings with elephants, and imaginary lava-heated homes), the core content provides valuable insights for HVAC and refrigeration technicians dealing with condensation and moisture issues in commercial refrigeration spaces. The hosts explain why humidity management is critical in grocery environments, where...
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The Finned-Tube Coil - Short #269
HVAC School - For Techs, By Techs
In this short podcast episode, Bryan explores the history of the finned-tube coil, which is what we use for heat exchange in air-source air conditioners and heat pumps. Air-source HVAC systems have copper tubes threaded through thin metal fins. This design was optimized to ensure the greatest possible surface area for heat exchange to occur. However, prior to the finned-tube coil, HVAC coils looked more like plumbing projects with bare copper loops, which were heavy, costly, and inefficient. In the early 1900s, HVAC was essentially plumbing with higher expectations; capacity was dictated...
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Are Two Are Better Than One: Understanding Tandem Compressors
HVAC School - For Techs, By Techs
In this comprehensive episode of the HVAC School podcast, host Bryan Orr sits down with three experts from Copeland to demystify tandem and trio compressor systems. Joining him are Gina Kahle (Multiples Engineering Manager with 12+ years at Copeland), Tyler Daniels (Product Management team member), and James Stevenson (Technical Sales veteran with 28 years of field experience). Together, they provide both the engineering perspective and real-world service insights that technicians need to understand these increasingly common systems. The conversation begins with the fundamentals: tandem and...
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The Tech That Tried to Beat the Compressor - Short #268
HVAC School - For Techs, By Techs
In this short podcast episode, Bryan tells the story of the technology that tried to beat the compressor... and still may someday. We associate cooling with refrigerant... and all the things that come with it, including compressor noise, oil, recovery machines and tanks, leaks, superheat, and regulations. However, there is a means of providing cooling with two pieces of metal and several semiconductors; current runs through it, and one side becomes cold, and the other side becomes hot. This technology is called thermoelectric cooling, associated with the Peltier effect. In 1834, French...
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VRF, Ductless and Humidity Control w/ Roman
HVAC School - For Techs, By Techs
In this comprehensive episode, Bryan and Roman dive deep into one of the most challenging topics in modern HVAC: making VRF (Variable Refrigerant Flow) and ductless systems perform effectively in humid climates like Florida. The conversation tackles a common misconception that inverter-driven equipment automatically handles humidity well simply because it can "turn down." Roman emphasizes that successful application of VRF technology in humid environments requires skilled professionals who understand building science, envelope integrity, and proper system sizing. The biggest takeaway? If...
info_outlineIn 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 Planning: Real examples of expensive mistakes from inadequate user requirements, including business software failures and HVAC mismatches
- Structured Selection Process: Step-by-step methodology for equipment selection from initial use definition through final verification and purchase
- Needs vs. Wants Prioritization: Framework for distinguishing between essential requirements and desirable features to avoid decision paralysis
- Electrical Meter Selection: Detailed walkthrough showing how to narrow 38 options to 2 viable candidates using systematic evaluation criteria
- HVAC System Selection Complexities: Load calculations, customer expectation management, and the importance of understanding actual usage patterns
- Customer Psychology and Expectations: Understanding why customers may want noise from systems, visual confirmation of operation, and familiar operational feel
- Commercial Equipment Considerations: Rooftop unit replacement challenges, curb adapters, crane access, and the complexity of retrofit installations
- Installation and Commissioning: The critical role of proper system setup, customer training, and setting realistic expectations for new equipment operation
- Risk Assessment in Selection: How complexity and potential failure costs should determine the formality and thoroughness of your selection process
- Data Collection for Future Decisions: The value of documenting system performance during routine maintenance to inform future replacement decisions
- Hidden Costs and Considerations: Factors like electrical requirements, ductwork compatibility, equipment accessibility, and service support that impact long-term ownership costs
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