Hvac School - For Techs, By Techs

This podcast episode focuses on the critical shortage of HVACR technicians and installers across the industry. The hosts discuss the massive gap that exists, with estimates of nearly 200,000 open roles expected in the next few years. They are joined by Lenny Diaddario from Copeland's contractor services department and Chris Harris from the educational nonprofit National Coalition of Certification Centers (NC3). Lenny and Chris explain the various initiatives Copeland and NC3 have undertaken to help attract more people to the HVACR trades. This includes STEM education outreach to get kids interested from an early age, partnerships with organizations like SkillsUSA and PHCC, virtual reality training tools that allow interactive compressor teardowns, and comprehensive certification curricula developed in collaboration with subject matter experts and instructors. One major program they highlight is the "train the trainer" events where instructors from trade schools can get certified on the Copeland curriculum ove

In this episode of the HVAC School Podcast, Bryan interviews Rachel Kaiser, a chemist with a passion for making science more accessible and understandable, especially when it comes to the topic of combustion. Rachel shares her background of how her family's restaurant business sparked her early interest in chemistry and the science behind mixing ingredients to produce desired results. Rachel dives deep into explaining the fundamental chemistry behind the combustion process. She breaks down the three key components required for combustion to occur - fuel, oxygen, and a heat source - and how the ideal chemical reaction is represented. However, she emphasizes that in the real world, factors like using natural gas (a mixture of gases) as fuel instead of pure methane and air (also a mixture) as the oxygen source lead to incomplete and imperfect combustion reactions. The discussion highlights the importance of combustion analysis and monitoring for byproducts like carbon monoxide (CO) and nitrogen oxides (NOx). Rac

In this short episode of the HVAC School podcast, Bryan talks about hoses and their various types and applications, particularly focusing on NAVAC hoses. Charging hoses (NAVAC: NH5 and NH5L) ideally shouldn't be longer than 5-6 feet, as the longer the hose, the more refrigerant it will hold. Manifold gauges also have leak points, so it's usually better to use probes instead of manifolds to help with charging. Charging hoses with ball valves (NH5S and NH5SC) can help you control the flow and are great for recovery. Whenever you use charging hoses, they will have a core depressor on one side only (usually the 45-degree side, if applicable); the right amount should be exposed, and the seal should be in good shape. Larger-diameter hoses with higher burst pressure are advantageous for recovery (though it's better to have separate hoses for recovery and evacuation). Larger-diameter hoses of a shorter length will allow you to get a higher flow rate, including cases where you have 1/4" connectors (though the F1028 &a

In this episode of the HVAC School podcast, Bryan interviews Pat Ward, an HVAC technician who specializes in servicing and maintaining computer room air conditioning (CRAC) units for data centers. They dive deep into the unique challenges and setups involved in cooling these critical facilities. Pat provides an overview of data centers, explaining that they are essentially industrial-scale computer rooms that generate immense amounts of heat from the servers and need precise environmental controls. CRAC units are specialized air conditioning systems designed to maintain the temperature and humidity within tight parameters suitable for electronic equipment. Unlike typical comfort cooling, CRAC units supply air around 70°F to avoid excessive dehumidification. Humidity control is crucial, often requiring supplemental humidifiers or dehumidifiers. Pat discusses common configurations like air-cooled direct expansion (DX) units as well as chilled water systems with computer room air handlers (CRAHs). Redundancy i

In Part 2 of the Rack Refrigeration Class at Kalos Services, Matthew Taylor discusses safeties, service, and more. Part 1 focuses more on the basic refrigeration circuit of a rack refrigeration system. When safeties are piped together, we have to keep in mind that they're a bit more complex than most HVAC refrigeration systems, especially when it comes to the oil side. All of these safeties and their proper installation can be located on the wiring diagrams. Safeties often respond to pressure, both in the refrigerant circuit and the oil circuit, but they may also respond to amperage or temperature. Each compressor on a rack has its own safety controls, but all compressor safeties should be wired in series. Overloads may measure temperature or amperage and break the circuit if it detects unsafe conditions. We also deploy demand cooling strategies to cool the compressor and help control compression ratios. We can also control capacity with staging strategies. Mechanical controls may be able to communicate with

This episode dives into an interesting and pragmatic discussion about how HVAC contractors can better balance their workload throughout the year. Kevin from Haven shares insights from observing HVAC businesses across the country and how some are taking a more strategic approach to triaging work. The main idea is to get systems up and running in the peak summer months when demand is highest, while also collecting data and making notes for more in-depth commissioning, ductwork upgrades, IAQ improvements, etc. that can be tackled in the fall "shoulder season." The hosts discuss the market forces that drive the typical reactive cycle - consumers waiting until systems fail to call for service, companies prioritizing new equipment installs when demand is high to boost revenue, etc. However, they propose a model where contractors are more proactive about maintenance, communication, and expectation-setting. Install the right-sized equipment over the summer, document issues to revisit later, use data loggers to analyz

In this insightful episode of the HVAC School Podcast, Ty Brannaman, an exceptional educator and trainer, shares his unique approach to making learning not just effective but also engaging and memorable. He delves into the art of connecting with students, unlocking their curiosity, and fostering a love for learning. Ty emphasizes the importance of understanding that not all students learn in the same way. He advocates for finding creative ways to capture their attention and spark their interest, whether through hands-on experiments, relatable analogies, or thought-provoking demonstrations. By tapping into students' existing experiences and curiosities, Ty creates an environment where learning becomes an exciting adventure rather than a chore. One of the key takeaways from the conversation is the power of the Socratic method. Ty encourages educators to ask questions that challenge students' assumptions and encourage them to think critically about the subject matter. By fostering a sense of exploration and

This podcast episode is Part 1 of a Kalos class on rack refrigeration given by Matthew Taylor. This first segment focuses on the basic refrigerant circuit and oil management of a parallel rack system, common in market refrigeration. Parallel racks follow the same general process as any other compression refrigeration system. However, they contain multiple compressors on a single rack. These systems have multiple suction lines that tie into one single suction header that feeds into multiple compressors. The suction side of the piping is usually a long distance with varying elevations; risers are vertical stretches of piping that carry oil and refrigerant up and pose a challenge for oil return. The compressor takes low-pressure vapor on the suction side and turns it into high-pressure vapor on the discharge side. From there, the condenser rejects heat from the refrigerant, which brings the superheated vapor down to saturation temperature and further rejects heat to make the refrigerant fully liquid (subcooled).

Standard 310 is a technical workflow created by ACCA, ResNet, and ANSI for grading the installation of HVAC systems, typically in new home construction. It plays a crucial role in obtaining Energy Star certification, which can qualify homeowners for tax credits under the Inflation Reduction Act. The five steps of Standard 310 are design review, duct leakage test, total system airflow, blower fan watt draw, and refrigerant charge verification. In this podcast episode, host Bryan Orr is joined by guests Chris Hughes and Eric Kaiser to discuss Standard 310 and its implications for HVAC contractors. The standard aims to ensure that HVAC systems are installed correctly and operate as designed. The process involves a third-party HERS rater conducting various tests and measurements, which contractors need to be prepared for. Proper duct sealing, airflow settings, and refrigerant charging are critical for passing the assessments. One of the challenging aspects highlighted is the refrigerant charge verification step.

In this short Q&A podcast episode, Bryan answers Gunther's question about kitchen exhaust and makeup air. Gunther asked if there were any studies that showed that makeup air should come very close to the hood to avoid infiltration. He also asked how to educate others who push back against the idea, particularly in kitchen exhaust systems of around 600 CFM. Commercial facilities, especially restaurants, bring in makeup air to balance out the air being exhausted. There are costs associated with makeup air, but there are plenty of valid reasons to add it to residential structures. Being able to control the makeup air allows us to control where we bring air in from (especially when it comes to drawing in humid air or dirty attic air from gaps and cracks, particularly in vented attics). Open-combustion appliances in the building envelope are also prone to backdrafting if the structure is under negative pressure. The structure is also more likely to have its dryer vents experience leaks under negative pressure.

This episode featured Bryan Orr interviewing Sam Myers, the building science consultant at Retrotec. Retrotec manufactures products like blower doors and duct testers for measuring air tightness and leakage in buildings. Sam discussed his role at Retrotec, which involves training contractors on using their tools properly, product design, software testing, presenting at conferences, and running trade show booths. He talked about the demanding travel schedule this requires but also the rewards of educating the industry. The main topic was duct leakage testing - why it's important, how it's done, interpreting the results, and investigating and fixing duct leaks when problems are found. Sam explained that while a duct leakage test provides a number, that number alone doesn't indicate if the leakage is acceptable or problematic. However, it points technicians in the right direction for further investigating issues like comfort problems, indoor air quality concerns, or high energy bills. He provided tips on using t

In this short Q&A podcast episode, Bryan answers Jeremy's question about checking the charge on rooftop units, and he gives some RTU tips. Rooftop units often come in sets, so you can use a thermal camera to look at all of the RTUs and compare them. A thermal imaging camera may even show you where subcooling begins in the condenser, which can be a useful diagnostic hack. Try to avoid hooking up gauges each time you check the charge on a rooftop; RTUs have a fixed factory charge, and losses from your gauges can add up over time. Your senses will also come in handy; check for odd sights, sounds, and smells. Checking suction pressure and superheat is less risky and imperfect, but it'll give you some diagnostic data. You can also check discharge temperatures to check for signs of compressor overheating (remember: 225 stay alive).  Here are some tips for RTUs: Get familiar with the service manual and wiring diagrams; these items will help you with the job and help you build on your knowledge of RTUs in genera

This episode features an insightful conversation with Brynn Cooksey, an experienced HVAC contractor and trainer from Southeast Michigan. Brynn shares his expertise in conducting proper load calculations, sizing the equipment correctly, improving duct design, and addressing common issues contractors face. Brynn emphasizes the importance of performing accurate load calculations, especially in older housing stock where equipment is frequently oversized by 50% or more. He discusses how oversized equipment leads to short cycling, poor efficiency, and increased utility costs for homeowners. His approach involves educating customers by involving them in the measurement process and using metrics like "duct deficiency" to demonstrate the inefficiencies of their current systems. The discussion then shifts to heat pumps and the unique challenges of implementing them in cold climates like Michigan. Brynn advocates for a "dual fuel" approach, utilizing heat pumps for efficiency while supplementing with gas heat during ext

In this short Q&A episode, Bryan answers podcast listener Cooper's question about starting an internal training program. Eugene Silberstein has been on the podcast before to offer his perspective on this topic, which you can listen to HERE.  Bryan recommends a combination approach: instructor-led, hands-on, and self-paced learning, all deployed together. Hands-on learning often gets missed, and we can give inexperienced techs experience with some basic troubleshooting tasks or breaking down and reassembling things. The Socratic method can also be employed here; the instructor can ask their trainees questions instead of the other way around. When the instructor is the one who asks the questions, they allow their trainees to be wrong, learn from their mistakes, and make their own connections to the fundamentals. Learning plans and curriculums are great for giving trainees a structure, but they need to be reinforced with the hands-on component in this trade. When determining what to teach, try to focus on w

This podcast episode is Bryan Orr's presentation at the 6th Annual HVACR Training Symposium: "Humility in Thought Leadership." Bryan reflects on his own journey as a trades educator, business owner, husband, and father, sharing personal anecdotes and insights that resonate with anyone in a position of influence. Bryan begins by acknowledging the challenge of maintaining humility in the face of success and recognition. He emphasizes the need to continually shift our focus from a mindset of "deserving" to one of "serving" others. By embracing humility, we not only become more effective leaders but also create an environment where those around us can grow and thrive. Throughout the episode, Bryan encourages listeners to embrace vulnerability and be open to feedback from those who care about them. He stresses the importance of surrounding oneself with people who are willing to hold you accountable and challenge you when necessary. This accountability, he argues, is crucial for personal growth and maintaining a gr

This short podcast is a Q&A based on a question submitted to us by Andy Holt. Bryan gives some tips on how to go from service tech to service manager. Service managers may have better pay, but they also have different sources of stress than service technicians, and not all service tech skills will translate well to management. Service techs and service managers have completely different skill sets, and they have to be able to gain satisfaction from different sources. Service techs are satisfied by solving problems, and they get immediate dopamine hits whenever they use their brains and hands to fix someone's AC. Service managers have to find satisfaction in big wins for their team. Service managers have to manage processes and procedures around customer service; they are involved with customer service representatives and dispatchers. They also handle the most difficult clients and situations, so they need to be able to resolve conflict and stay calm in tense situations. Good service managers also learn to

This episode was recorded live on location at the 2024 ACCA conference in Orlando. Bryan starts by interviewing Marissa, a co-founder of Conduit Tech, a software company providing load calculation and sales tools for HVAC contractors. Marissa shares insights into what it takes for contractors to successfully adopt new technology in their businesses. She emphasizes the importance of having support at multiple levels of the company, a willingness to thoroughly learn the new software, and providing feedback to the developers. Marissa stresses that Conduit actively seeks input from contractors to continue improving their product's workflow integration. Learn more about Conduit Tech at https://getconduit.com/.  In the second segment, Bryan talks to Martin Hoover, the incoming chair of ACCA (Air Conditioning Contractors of America). Martin discusses the value ACCA provides through training, advocacy, and facilitating peer group interactions. He highlights how ACCA conferences allow contractors to learn from industr

In this insightful podcast episode, the host delves into the crucial aspects of positive and productive client communication, drawing from his extensive experience in the residential air conditioning industry. He emphasizes the importance of setting the right tone, bringing energy, building trust, and adapting to different customer personalities when interacting with clients. The host highlights the key elements of positive communication, such as maintaining a consistently upbeat and enthusiastic demeanor, while also being mindful of the client's preferences. He stresses the importance of active listening, to truly understand the customer's needs and concerns, rather than simply waiting for your turn to speak. The host also touches on the challenges of dealing with difficult customers, such as those who are overly focused on price or technical details, and provides strategies for navigating these situations with patience and professionalism. The discussion then shifts to the productive side of client communic

Roman Baugh, Matthew Condron, and Luke Peterson discuss the importance of proper condensate drain installation and maintenance, particularly in commercial applications. The conversation begins with the hosts examining the typical drain configurations seen in different regional markets, highlighting the significant variations in practices across the country. Sizing and configuration of condensate drains can have a significant impact on system performance, especially in high-static pressure systems. He emphasizes that the "one-size-fits-all" approach of using a 2-inch trap is often insufficient, as the static pressure within the system can overcome the trap's ability to prevent air from being sucked into the drain line. The hosts discuss the chart Roman presents, which provides guidance on selecting the appropriate trap depth based on the static pressure of the system. The discussion then delves into the challenges associated with maintaining condensate drains, including the buildup of debris and the potential

In this short podcast episode, Bryan explains electronic expansion valve (EEV) types. EEVs perform the same function as TXVs, but they operate electronically, not mechanically. The EEV makes sure that the evaporator is full of the right amount of refrigerant at saturation; it doesn't just affect evaporator pressure. We don't want high superheat (due to inefficiency), and we don't want zero superheat (due to the risk of compressor failure). EEVs commonly have a stepper motor with a set of discrete settings depending on how many rotations the motor has made. It can be fully open or fully closed, and the number of rotations can set the valve at any value between fully open and fully closed; it's open or closed by a specific percentage. Instead of a bulb and external equalizer, a pressure transducer and temperature sensor report to the controller and give the controller the data it needs to open or close the EEV to maintain a specific superheat. Pulse-width modulation (PWM) allows an EEV to open and close rapidly