HVAC School - For Techs, By Techs
Career
Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.
Location:
United States
Description:
Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.
Language:
English
Website:
http://hvacrschool.com/
Email:
bryan@hvacrschool.com
Episodes
White Shirt Techs - Manifesto
1/9/2025
This unique podcast episode is a commentary on the phenomenon of "white shirt techs" in the HVAC industry - a term that refers to technicians who focus heavily on sales and maintaining a pristine appearance rather than technical expertise. While there's nothing inherently wrong with having good sales skills or maintaining a professional appearance, there needs to be a balance with actual technical competency. The episode serves as part of a manifesto series heading into 2025, addressing important industry trends and concerns.
There is a delicate balance between sales and service in the HVAC industry, particularly in residential services. Some companies and technicians may prioritize metrics like average ticket price and five-star reviews over providing genuine solutions to customers' problems. While it's important to discuss money and options with clients, we shouldn't resort to fear tactics or make promises that products can't fulfill, particularly in areas like indoor air quality solutions and UV lights.
The podcast raises important questions about professional identity and integrity in the HVAC field. Technicians should occasionally step back and think about whether they've lost their passion for actually fixing equipment and solving technical problems in favor of focusing solely on sales. He argues that the best residential technicians maintain their interest in the mechanical aspects of the work, even as they develop their customer service and sales skills. The episode concludes with a call for technicians and companies to invest more time in technical training and to maintain their commitment to solving real problems rather than just selling solutions.
Key Topics Covered:
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 6th 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
Duration:00:34:07
Q&A - Double Flares - Short #225
1/7/2025
In this short podcast episode, Bryan answers a listener-submitted question about double flares and their application in the HVAC/R industry.
Flare connections are common in certain types of equipment, and they connect the copper to the appliance. As a result, when we make a flare, our goal is to make it leak-free. A regular flare requires you to cut the copper, clean it, put the flare nut on, and make the flare with a flaring block (or a flaring tool). You can also put a little bit of oil on the flare cone to prevent galling. Modern power flaring tools are common nowadays, especially in markets where we install a lot of mini-splits. We also use torque wrenches to tighten the flare connection according to the manufacturer's specs.
In mission-critical applications where we have toxic or flammable refrigerants under high pressure, we especially want leak-free connections. Double flares make more sense in these scenarios for extra security (though we may use different connection types). A double flare requires you to use a double-flare die that flares over the edge, though those double-flare dies are more common in older flaring kits and may not exist for power tools or spin tools.
Double flares are usually less practical than other alternatives that exist on the market. For example, some manufacturers make flare gaskets to reduce the likelihood of leaks, and these are functionally similar to a double flare.
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 6th 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
Duration:00:09:07
Can You Coat Fiberglass?
1/2/2025
In this episode of the HVAC School Podcast, Bryan interviews Zach about duct coatings and their applications in HVAC systems, particularly focusing on the Hardcast RE500 product. The discussion delves into the importance of proper duct coating applications and their benefits for both contractors and customers. Zach, who has extensive experience in duct cleaning and restoration, shares his expertise on the proper application and benefits of duct coating systems.
The conversation explores how modern ductboard comes with a clear coat that offers some protection, but additional coating can provide significant benefits, especially in high-velocity areas near equipment. They discuss how coating creates a smoother, more cleanable surface that's almost comparable to sheet metal in terms of friction resistance. Zach emphasizes that coating should only be applied after proper cleaning, as it's not meant to cover up dirty ducts but rather to protect and improve cleaned surfaces.
A significant portion of the discussion centers around the practical applications for HVAC contractors, particularly during equipment changeouts. Bryan proposes the idea of coating the first 5-10 feet of ductwork near equipment during changeouts, as these areas experience the highest velocity and are most susceptible to fiber shedding and moisture issues. The conversation also addresses the cost-effectiveness of coating versus replacement, with the coating being approximately one-fourth to one-fifth the cost of replacement.
Key Topics Covered:
Learn more about NADCA at https://nadca.com/.
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 6th 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
Duration:00:29:00
Q&A - Metacognition and More - Short #224
12/31/2024
In this short Q&A podcast episode, Bryan answers a listener-submitted question about metacognition and more about critical thinking, reflective analysis, and challenging biases.
Metacognition is the ability to think about thinking; it's about breaking things down, noticing your own thoughts, and understanding the "why" behind their thoughts. Metacognition is beneficial when applied to the "wide" aspects of the "wide-narrow-wide" mindset; it helps with broad analysis and is less useful during the narrow phase when you want a flow state.
Unpacking our biases is useful, but it's most important in positions of power. Biases and assumptions have the most widespread effect when they're leveraged on others by authority figures, but they show up in any position of power (or lack thereof). Many of these are baked into us as mental shortcuts called heuristics, which are the same things that tell us not to touch stoves for survival; they're ingrained, but we have to be able to challenge those and unpack the reasons when it comes to assumptions about other people. However, this activity is time-consuming and not best used in situations where immediate action is needed.
Humans have a strong proclivity for pattern recognition for survival reasons. However, one of the downsides of strong pattern recognition is the risk of associating correlation and causation without taking the proper investigative steps to confirm the relationship between things. The scientific method exists to test a hypothesis and explore the relationship between things in our world. Learning and being open to complex relationships are components of a great mindset to apply to HVAC work as well, and humility and curiosity are at the forefront.
Franco, Zeno E., Kathy Blau, and Philip G. Zimbardo. "Heroism: A conceptual analysis and differentiation between heroic action and altruism." Review of general psychology 15.2 (2011): 99-113. https://doi.org/10.1037/a0022672
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 6th 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.
Duration:00:22:22
Redux - The Lost Art of Steam Heating w/ Dan Holohan
12/26/2024
In today's podcast, Bryan talks with legendary Hydronics author and trainer Dan Holohan about the history of steam heating and some practical applications of old ideas. Recently, Dan has been working on more novels, having published two of them over the past few months.
Steam heating is a “lost art” nowadays; it has become increasingly uncommon and has been disappearing since the Vietnam War. Many people who understood steam heating either retired or died after the Vietnam War. Many elements of steam heating are difficult to understand or surprising. (For example, steam pressure has a surprising relationship with velocity: low-pressure steam moves through piping much more quickly than high-pressure steam.) So, Dan Holohan is on a mission to revive that knowledge and teach the newer generations about the lost art.
There are many older steam heating systems still operating today, especially in the older large buildings in New York. Dan learned a lot about steam heating when working on these old systems and optimizing them. Most of the time, he optimized those systems by removing unnecessary accessories, not by adding components like steam traps.
Many old boilers used coal as a heat source. Nowadays, many old boilers have been fitted with conversion oil burners with thermostats, but they are still piped for coal. Some systems now have multiple risers or massive vents on the main riser to prevent the thermostats from getting too hot too early and satisfying the thermostat too early. We call that master venting, which reduces pressure and allows steam to move very quickly and efficiently.
Dan also discusses:
Find out more about Dan and hydronic heating at HeatingHelp.com.
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 6th 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.
Duration:00:44:34
Q&A on Superheat - Short #223
12/24/2024
In this short Q&A podcast episode, Bryan answers a listener-submitted question about superheat, including what it is and how we measure it.
Superheat is the number of degrees a refrigerant is above its saturation point. The saturation point is where you will have a liquid-vapor mix, so superheat only exists when a substance is a vapor. Saturated refrigerant should only exist in the evaporator and condenser, during which it is being boiled or condensed.
We usually measure superheat at the evaporator coil outlet and compressor inlet. The superheat at the evaporator outlet is usually around 5-14 degrees Fahrenheit, and it's often between 10 and 20 degrees at the compressor inlet (compressor superheat). However, many systems try to get lower superheat values, and some manufacturers may require higher superheat values at the compressor inlet to prevent liquid refrigerant from getting into the compressor. Accumulators can help keep liquid refrigerant out of the system as well. We may also measure superheat coming out of the compressor on the discharge line (discharge superheat); this superheat may exceed 100 degrees Fahrenheit. Discharge superheat can let you know if the compressor is overheating the oil and causing breakdown or carbonization.
We use superheat to set the charge for fixed-orifice metering devices (as opposed to subcooling for TXVs), as superheat is a measure of how well we're feeding our evaporator coil. When the system is off, the superheat will be 0. A system will equalize, and the refrigerant will be at saturation when that happens.
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 6th 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.
Duration:00:10:04
Duct Cleaning - How Long & How Often?
12/19/2024
In this episode of the HVAC School podcast, Bryan interviews Zach from Southeast Clean Air Solutions about the intricacies of professional duct cleaning. Zach specializes in addressing duct cleaning challenges specific to the Southeastern climate, with a particular focus on fiberglass-lined ducts. The conversation delves into the complexities of cleaning different types of duct systems, highlighting the significant variations in time, technique, and approach depending on the duct materials and home configuration.
The discussion reveals that duct cleaning is far more nuanced than many homeowners realize. A typical residential duct cleaning can take between six to eight hours, with metal ductwork being significantly faster to clean than flexible ducts or fiberglass-lined systems. Zach emphasizes the importance of careful cleaning techniques, especially with delicate flex ducts that can easily be punctured or damaged during the cleaning process. He recommends a two-person approach, with one team member working inside the home and another in the attic or crawl space to ensure thorough and safe cleaning.
Beyond the cleaning process, the podcast explores critical maintenance strategies for maintaining clean and efficient HVAC systems. Zach and Bryan discuss the importance of proper filtration, home maintenance, and understanding when duct cleaning is truly necessary. They challenge the common misconception of a fixed cleaning schedule, instead advocating for system assessment based on specific conditions like household dust, humidity, and the health needs of home occupants.
Key Topics Covered:
Learn more about NADCA and find certified duct cleaning contractors at https://nadca.com/.
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 6th 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.
Duration:00:29:38
Are EVs an Opportunity? - Short #222
12/17/2024
In this short podcast, Bryan talks about electric vehicles and whether EVs present an opportunity for HVAC technicians. The residential sales lead at Kalos recently mentioned that keeping an EV in a conditioned garage is advantageous, and it's an upgrade we can offer our customers.
In hot weather, EV battery performance and health can be degraded. On top of that, the vehicle consumes power when the vehicle gets hot so that the A/C can control the climate inside the car and preserve the interior. Most people also charge their electric vehicles in the garage at night, so it would stand to reason that conditioning the garage can yield energy savings and improve vehicle longevity. Attic encapsulation above the garage is also an option to limit warm, moist attic air from leaking into the garage; HVAC upgrades can include using closed-cell foam to encapsulate the attic and install a dehumidifier in there.
Conditioning a garage requires you to think about insulation. In our market (Florida), block walls don't insulate very well. Even when we can't do very much with the walls, we can usually use some polyiso boards inside the garage. However, we could get some moisture challenges, and carbon monoxide could be an issue if combustion appliances are in the garage (like furnaces, water heaters, or gas-powered cars). We can recommend using heat pump water heaters, and we should quote a low-level CO monitor in cases when garages have a CO risk.
It's important to make sure the garage remains separate from the rest of the house even when we do these upgrades. Keeping the garage separate helps prevent chemicals from getting into the airstream, especially yard chemicals or cleaners.
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 6th 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.
Duration:00:09:22
Choosing HVAC Cleaners w/ Becca from Viper
12/12/2024
The podcast delves into the world of HVAC chemical solutions through an in-depth conversation with Becca Stamey, the marketing director at Refrigeration Technologies. The discussion provides insights into the company's unique approach to developing cleaning products, rooted in a commitment to safety, effectiveness, and customer feedback. Founded by John Pastorello, a chemist turned HVAC technician, the company has always prioritized creating products that are non-toxic, non-corrosive, and environmentally friendly.
Becca highlights the range of Viper products, from condenser and evaporator cleaners to pan and drain sprays and all-purpose cleaners. Each product is carefully formulated with specific purposes in mind, such as the enzyme-based evaporator cleaner designed to address odor issues and break down biofilm. The conversation emphasizes the company's innovative packaging, particularly the Venom Packs, which offer concentrated, durable, and space-efficient solutions for technicians. The podcast also underscores the company's commitment to quality control, with U.S. manufacturing and personal oversight from the leadership team.
The episode provides a behind-the-scenes look at Refrigeration Technologies' growth and dedication to the HVAC community. The company has been named to the Inc. 5000 list of top-growing companies for three consecutive years and is expanding its manufacturing capabilities. Becca discusses the company's social media presence and community engagement, including their "Tech of the Month" program, which highlights and celebrates HVAC technicians who embody the company's values.
Key Topics Covered:
Learn more about Refrigeration Technologies at https://www.refrigtech.com/. You can also follow Refrigeration Technologies on Instagram, LinkedIn, Facebook, YouTube, and TikTok (ViperHVAC).
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 6th 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.
Duration:00:40:43
Q&A - Evap Placement - Short #221
12/10/2024
In this short podcast, Bryan talks about evaporator coil placement based on a question submitted by a listener, John. Evap coil placement differs in furnace applications versus air handlers.
When we use air conditioners with furnaces, we usually put evaporator coils on the positive side to protect the heat exchanger from rusting out during the summer (due to condensation and the chemical reactions that can occur with the metal heat exchanger). However, when it comes to air handlers, they're usually on the negative side. The coil is usually on the negative side of a fan coil or air handler because it keeps the blower motor cooler (though that doesn't make a huge difference in terms of performance).
The HVAC system will lose fewer BTUs to leakage when the coil is on the negative side, which is better for energy efficiency; those BTUs can reach the conditioned space rather than the closet, garage, or wherever it is stored. Pulling air over the evaporator coil on the negative side, however, could potentially lead to greater turbulence.
We run into challenges with evap coil placement on gas furnaces when we have dual fuel systems (a heat pump and furnace working together). You can't run gas heat over a heat pump coil due to the high head pressure, so a parallel setup would avoid the risks of high head pressure (downstream) or rusted-out heat exchangers (upstream).
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 6th 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.
Duration:00:07:15
Can Ducts Be Cleaned Ethically?
12/5/2024
In this episode of the HVAC School Podcast, Bryan interviews Zachary Ortwine, a duct cleaning professional who provides insights into ethical duct cleaning practices. The conversation delves deep into the complexities of cleaning different types of ductwork, the importance of proper assessment, and the potential challenges in maintaining indoor air quality.
Zach emphasizes the critical role of thorough inspection and honest communication with clients. He explains that not all duct systems are equally cleanable, and professionals must carefully assess factors like duct material, contaminant type, and cleaning feasibility. Metal ducts can be cleaned more aggressively, while fiberglass ducts require a more delicate approach. The discussion highlights the importance of understanding the underlying issues that contribute to indoor air quality problems, such as system design, maintenance, and home living conditions.
The podcast explores the evolution of duct cleaning technologies and safety considerations. Zach shares insights into modern fiberglass materials, which have improved safety compared to older versions, and discusses the importance of proper cleaning and coating techniques. The conversation also touches on broader indoor air quality challenges, including the impact of tighter building envelopes, ventilation issues, and the potential health risks of prolonged exposure to indoor contaminants.
Key Topics Covered:
Learn more about NADCA and certified professionals at https://nadca.com/.
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 6th 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.
Duration:00:41:32
Should I Fog or "Sanitize" My Ducts? - Short #220
12/3/2024
In this short podcast episode, Zach joins Bryan to answer a common duct maintenance question: Should I fog or sanitize my ducts?
The North American Duct Cleaners Association (NADCA) outlines the uses of chemical products. Adding chemicals is usually a last resort in flex or sheet metal (externally wrapped) duct systems; they should NOT be used on ducts with internal liners or are made of duct board or any other material with porous surfaces.
Fog is typically applied while a vacuum is running at the opposite end of the duct. It liquefies on surfaces, and a lot of contractors don't go in and dry off the duct surfaces. It's difficult to coat the entire interior of a duct system with the chemical to make it as effective as possible, and the residue creates a moist, sticky film that actually encourages microbial growth in the ductwork. On top of that, some people may be sensitive to the chemicals.
In many cases, replacing ductwork that has been confirmed to have microbial growth is more reliable. Chemical duct sanitation often has more of a perceived benefit than long-term results. The use of chemical cleaners in ductwork is similar to that of using some line set flushes without forcing a solid pig through the line set to pick up the residue afterward. Ultimately, the customer has to make an informed decision based on the problem and knowledge of the benefits and drawbacks of chemical solutions.
NADCA's white papers, including "Chemical Product Applications in HVAC Systems," are available at https://nadca.com/industry-professionals/nadca-white-papers.
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 6th 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.
Duration:00:09:16
Condensing Furnace Drain Guidance w/ AC Service Tech
11/28/2024
Bryan and Craig Migliaccio (AC Service Tech)dive deep into the complexities of managing condensate drainage in high-efficiency (90%+) gas furnaces. The conversation begins with a clear explanation of why these furnaces produce condensate in the first place - they have two heat exchangers that extract so much heat from the combustion gases that water vapor condenses out. This condensate is acidic (pH 3-5) and requires special consideration for drainage and disposal.
The discussion explores various challenges contractors face when installing these systems, particularly in cold climates where freezing is a concern. Craig shares practical solutions from his experience in New Jersey, including using larger diameter pipes for exterior drainage and creating air gaps to prevent complete freezing. They address the ongoing debate about whether to combine AC condensate lines with furnace condensate lines, noting that while it's technically possible, there are potential risks and code considerations to keep in mind.
A significant portion of the conversation focuses on code compliance and best practices for condensate disposal. The International Mechanical Code (IMC) provides several acceptable options for drainage, including floor drains, utility sinks, and standpipes. However, as Craig points out, local interpretations and requirements can vary significantly, making it crucial for contractors to maintain good relationships with their local inspectors and understand their specific jurisdiction's requirements.
Key Topics Covered:
Check out some of Craig's great educational books at https://www.acservicetech.com/.
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 6th 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.
Duration:00:38:57
How to Predict Air Flow Issues in the Sales Process
11/21/2024
Chris Hughes and Steve Rogers from The Energy Conservatory discuss TEC's TrueFlow technology and its crucial role in predicting airflow issues in the sales process, particularly for heat pump retrofits. They explain how the TrueFlow app helps contractors accurately measure both static pressure and airflow in existing systems, enabling them to predict whether proposed equipment changes will work effectively. This is especially vital when considering the growing trend of replacing gas furnaces with heat pumps, as the airflow requirements can differ significantly.
The conversation delves into a detailed example of replacing an 80% efficient 48,000 BTU furnace with a heat pump. They demonstrate how the airflow requirement would nearly double from 652 CFM to 1,200 CFM, potentially causing the static pressure to quadruple due to Fan Law 2 principles. This dramatic increase could lead to significant performance issues if not properly addressed during the system design phase. The experts emphasize that using TrueFlow during the sales process allows contractors to identify potential problems and necessary modifications before installation rather than discovering issues during callbacks.
The discussion also covers the ideal workflow for system assessment and sales, starting with customer comfort evaluation and proper load calculations. It's important to reduce loads through envelope improvements when possible, particularly in cold climates where heat pump retrofits are becoming more common. Proper system sizing often means going smaller rather than larger, contrary to common industry practices, and the worst HVAC systems are often found in expensive custom homes rather than tract housing.
Key Topics Covered:
Check out TEC's YouTube channel at https://www.youtube.com/@energyconservatory, and you can visit TEC's website at https://energyconservatory.com/.
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 6th 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.
Duration:00:46:44
MCA is 27 and the Breaker is a 50A - Short #219
11/19/2024
In this short podcast episode, Bryan and Mike from DITEK talk about what to do in tricky electrical scenarios, such as when the MCA is 27 and you have a 50A breaker.
When you size an HVAC system for compatibility with voltage monitors, like the DITEK Kool Guard, you need to pay attention to the MCA (minimum circuit ampacity), which should not be confused with MOCP (maximum overcurrent protection or breaker size). As long as the MCA is 40 amps or lower, you can attach the HVAC condenser to the Kool Guard. The KG2 also accepts wire sizes up to 6 AWG.
The Kool Guard is NOT a source of overcurrent protection; it is a voltage monitor rated for carrying current, which means ratings will be in MCA, not MOCP. MOCP is designed to deal with high starting amps and lets users know the maximum allowable current for a circuit so that it can trip properly when that current is exceeded. According to Section 440 of the National Electrical Code (NEC), motors with internal overload protection allow for a difference between the MCA and MOCP. You may find higher MOCPs on inverter-driven systems.
Learn more about DITEK at https://www.diteksurgeprotection.com/.
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 6th 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.
Duration:00:06:11
Deploying Surge Protection & Voltage Monitoring w/ DITEK
11/14/2024
Bryan discusses surge protection devices (SPDs) with Mike from DITEK, focusing on practical applications for HVAC contractors and how to provide value to clients. Mike emphasizes that surge protection is essential for modern HVAC systems, particularly given that they are typically the most expensive appliance in a home and increasingly rely on sophisticated electronic components like variable-speed compressors and inverter boards.
The conversation delves into installation best practices, with a detailed discussion of proper wiring techniques for SPDs. Mike explains that surge protectors should be installed in parallel with the circuit, typically at the disconnect, and addresses common concerns about double-tapping lugs and ground connections. He emphasizes the importance of keeping wire lengths as short as possible and provides guidance for installations both with dedicated disconnects and panel-direct connections.
A significant portion of the episode focuses on DITEK's Kool Guard (KG2) product, which represents an evolution in HVAC protection by combining surge protection with voltage monitoring. Mike explains how modern HVAC equipment, particularly inverter-driven systems, is increasingly sensitive to both over-voltage and under-voltage conditions. The Kool Guard monitors voltage on each phase independently and provides visual indication of fault conditions through LED indicators, making it easier for homeowners to identify potential issues without opening electrical enclosures.
Key Topics Covered:
· Why every modern HVAC system needs surge protection
· Installation locations and proper wiring techniques for SPDs
· The difference between line-side and load-side installation
· Ground connection best practices
· How to protect both condensers and air handlers
· The evolution from basic surge protection to voltage monitoring
· The importance of voltage monitoring for modern inverter-driven equipment
· How Kool Guard monitors voltage phase-to-ground vs line-to-line
· Common power quality issues beyond lightning strikes
· How to discuss surge protection with customers
· The limitations of utility-provided surge protection
· The impact of aging power infrastructure on power quality
· The advantages of USA-made surge protection products
· How voltage monitoring prevents damage from brownouts and over-voltage conditions
· The pre-programmed voltage protection ranges in Kool Guard
· Visual indication features for fault conditions
Learn more about DITEK at https://www.diteksurgeprotection.com/.
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 6th 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.
Duration:00:35:32
Pumping vs. Compression - Short #218
11/12/2024
In this short episode, Bryan clears up the confusion behind pumping vs. compression.
Pumping is usually associated with liquid. Liquid, like vapor, is a fluid, but it's a lot denser and is essentially incompressible because the molecules are close together. Liquid volume varies based on temperature and density, but we can't squish the molecules together. That's why compressors with very little axial and radial compliance fail when flooded; they can't compress the liquid. A circulator pump in a hydronic system is an example of a pump that pushes liquid along, but the pressure difference across the pump is minimal compared to that of a compressor; the same is true of liquid vs. vapor CO2.
However, vapor molecules are far apart and can be squished together to take up a smaller volume. That's why vapor can go through compressors, which take a fluid of one volume and apply pressure to shrink it to a smaller volume, raising the temperature in the process. Pneumatics, as opposed to hydraulics, utilize compression to move vapor around in a circuit. Recovery machines need to be able to compress vapor refrigerant and pump liquid into the recovery tank.
Compressors and pumps can either be positive displacement or non-positive displacement systems. A positive displacement system creates a trap and forces a fixed amount of fluid through a system, like a scroll compressor or a circulator pump. Refrigerant volumes may vary because vapor density varies with temperature and pressure (the volume flow is the same, but the mass flow varies). A condensing fan motor, on the other hand, is dynamic and varies the volume of air it moves in response to pressure, as the mechanism relies on velocity and kinetic energy to move air.
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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Duration:00:09:32
Building Tech Confidence w/ Refrigeration Mentor
11/7/2024
Trevor Matthews returns to the HVAC School Podcast to discuss building tech confidence and personal growth in the HVAC and refrigeration industry. The conversation explores the transformative power of self-investment, continuous learning, and maintaining a positive mindset. Trevor shares his personal journey from a hesitant technician to a successful business owner, highlighting the importance of pushing beyond comfort zones and embracing continuous improvement.
Some fundamental mindset shifts are necessary for professional development. Trevor candidly discusses his early career struggles, including his initial fear of public speaking and technical challenges. He emphasizes that confidence isn't something that happens overnight but is built through consistent effort, studying, and maintaining a willingness to learn. The key to the growth mindset is to focus on personal progress instead of comparing your achievements to those of others, and it's a perspective that can dramatically impact professional and personal growth.
Self-investment consists of dedicating time to learning, staying physically and mentally healthy, and maintaining a positive attitude, and it can open up unprecedented opportunities. Many technicians have transformed their careers by adopting a growth mindset, continuously seeking knowledge, and being willing to step outside their comfort zones.
Key Topics Covered:
Recommended Resources Mentioned:
Check out Refrigeration Mentor at https://refrigerationmentor.com/ or email Trevor at trevor@refrigerationmentor.com.
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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Duration:00:46:56
Molecular Transformator - Short #217
11/5/2024
In this short podcast episode, Bryan talks about the CPS Molecular Transformator and what it does.
The Molecular Transformator is a version of a tube-in-shell heat exchanger, which is a method of exchanging heat from one fluid medium to another fluid medium. Tubes containing a fluid pass through a shell containing water or glycol, and there is a heat exchange between that secondary fluid and the fluid being circulated in the tubes. In a Molecular Transformator, the fluid being circulated is recovered refrigerant, and the secondary fluid is water (in a bucket), which absorbs heat from the refrigerant and cools it down to make sure that the refrigerant enters the recovery tank as a liquid.
Refrigerant recovery machines have condensers inside of them, but they are quite small and don't hold a lot of refrigerant by design; many recovery machines use microchannel coils. A lot of the time, the refrigerant leaving a recovery machine is a liquid-vapor mix and too high-temperature; a lot of people run a hose over the tank or put it in a bucket of ice. The "Molecular Transformator" tries to settle the vapor molecules down into a liquid; it transforms the vapor molecules using the same mechanism as a tube-in-shell heat exchanger.
The main issue is that there will be leftover refrigerant in the Molecular Transformator after recovery. However, you can mitigate this problem with ball valves and proper purging. Do so responsibly to avoid venting refrigerant.
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Duration:00:09:11
Surge Protection Basics w/ DITEK
10/31/2024
In this enlightening episode, we sit down with Mike, a 20-year veteran from DITEK, a leading American manufacturer of surge protection devices based in Largo, Florida. The conversation begins with a brief discussion about recent hurricane impacts in the Tampa Bay area, where DITEK maintains its 65,000-square-foot manufacturing facility. Mike shares how the company, despite facing challenging weather conditions, continued its operations and maintained its commitment to American manufacturing.
The bulk of the discussion centers around surge protection technology and its critical importance in protecting HVAC systems and other electronic equipment. Mike provides an excellent analogy, comparing surge protectors to pressure relief valves for electrical systems. He explains how Metal Oxide Varistors (MOVs) work as semiconductors that create low impedance paths to ground when voltage exceeds certain thresholds. The conversation delves into the evolution of MOV technology, particularly the development of thermally protected MOVs that provide enhanced safety features.
The episode also addresses common misconceptions about surge protection, particularly the belief that surge protectors are primarily for lightning protection. Mike explains that while lightning strikes are a concern, especially in areas like Florida, approximately 65% of surges actually originate from within facilities themselves, often from equipment cycling on and off or other power quality issues. He emphasizes the importance of proper installation, particularly regarding ground connections and lead lengths, noting that every six inches of wire length can add about 100 volts to the clamping voltage of the device.
Key Topics Covered:
Learn more about DITEK at https://www.diteksurgeprotection.com/.
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.
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Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.
Duration:00:39:03