HVAC School - For Techs, By Techs

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.

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.

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.  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.

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: Building professional confidence The importance of continuous learning Overcoming fear and self-doubt in technical careers Strategies for personal and professional growth Maintaining a positive mindset Investing in self-improvement Balancing work, health, and personal development The power of small, consistent actions Avoiding comparison with others Techniques for staying motivated Recommended resources for personal development Recommended Resources Mentioned: Book: "Limitless" by Jim Kwik Book: "Good to Great" by Jim Collins Book: "Think and Grow Rich" by Napoleon Hill Book: "Mastery" by Robert Greene Podcast: Hidden Brain Podcast: AC Service Tech   Check out Refrigeration Mentor at https://refrigerationmentor.com/ or email Trevor at [email protected].  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.