HVAC School - For Techs, By Techs

Kimberly Llewellyn from METUS joins the podcast to talk about the value system around the trades and why the trades aren't more respected. In many cases, the people who are involved in engineering and design miss the practical details that the tradespeople would be able to pick up on. In many cases, tradespeople aren't consulted early enough in the design process, and their input deserves to be brought to the table. Often, not everyone on a project team is on board with the project's goal, and the trades need to be on board from the beginning to work towards the same goal as the architects and engineers. However, the trades aren't as respected because of the current American dream's emphasis on 4-year college, even despite the student loan debt problem many college graduates have. Despite that, building and troubleshooting systems that are necessary for survival is a fundamental skill for society. The trades can be especially hard on people and leave them feeling beaten down. To reengage the tradespeople and affirm their value, we need to give them credit for their contributions and expertise. It would also benefit younger generations if we could map out a trades career path and make the career progression opportunities clearer. Kimberly and Bryan also discuss: Kimberly's experiences with the trades Theory vs. practice 4-year college, the trades, and our current value system in education Professionalism and being treated as professionals Revising contracts and liability concerns (for contractors/subcontractors) Having mutual respect Consultation and what it means in the trades Working for manufacturers and other career opportunities Contracting as a "race to the bottom" Funding training programs vs. investing in people Mentorship in the trades Underpriced bids and pricing methods If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Eric Kaiser and Ty Branaman return to the podcast to talk about getting more people into the trade. They focus on how the HVAC/R industry could be better at attracting and training skilled workers, not just getting more bodies to fill HVAC/R tech and installer positions. People are starting to see more value in skilled trades careers, but it's difficult to find people who share your company's values and want to grow as HVAC/R professionals. Skilled tradespeople need time, education, and money invested in them, so it can be difficult for HVAC/R business owners to make those investments when other jobs pay close to the same without the same degree of investment from the company and the employee. To attract more people to the trade, HVAC/R business owners ought to focus on how to give their employees a means of giving a good life. That means making incremental changes to employee pay, benefits, and training to make the trades a competitive option for people who want to improve their skills and grow. We could consider increasing entry-level pay to attract skilled people, allowing us to be more selective in our hiring. Performance reviews can also be more goal-focused to help HVAC/R talent grow within a company. Companies also ought to focus on training their tradespeople to use the many tools at their disposal nowadays; providing these tools and acknowledging the needs of employees will make the industry much more appealing and competitive. Eric, Ty, and Bryan also discuss: Labor organizations Making gradual changes to the industry Competing with other similar industries Changing landscape of job ads and applications "Back in my day..." Ways of providing tools If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Genry Garcia returns to the HVAC School podcast to talk about what becoming a complete tech really means and entails. He talks about his professional journey and what we must do to address our deficiencies. Career progression looks a bit different for everyone, with some technicians going to trade school and others starting as helpers and working their way up. We get used to taking readings and start noticing patterns. Then, we start understanding why we see certain pressures. Our experiences are our most valuable tools for becoming better technicians, but they can be reinforced with other learning materials, including books and podcasts. There comes a point when we acknowledge that we are solid technician but may want to specialize in a certain aspect of the trade. For Genry, that was building performance and humidity control; along the way, he listened to people who knew more than him and took on many jobs that he'd learn from and would keep him humble. Everything goes back to the basics; we have to be able to solve all the basic problems and understand the fundamentals. Then and only then can we start thinking about building performance and focus on becoming experts at it. However, we also have to assess our ecosystem and see if it would allow us to grow or if it's more suited for stability. We also have to be willing to be wrong and grow from those mistakes. Genry and Bryan also discuss: The pros and cons of trade school Egos and admitting wrongdoing Mental models Humidity control Looking back on previous work with shame Building envelopes, pressures, and leakage Where and how to learn more about building science and performance Self-auditing and the Dunning-Kruger effect Get in touch with Genry on Facebook by joining his Facebook Group HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast in our electrical myths series, Bryan talks about some inductive current myths. There is a common myth surrounding voltage drop in inductive loads. When you decrease the voltage in a circuit with a resistive load, you'll see a relatively proportional drop in resistance (ohms) and current in accordance with Ohm's law. So, we'll see a decrease in current, but we have to keep in mind that load temperatures also affect the resistance (and the current, by extension). Some people will claim that reducing the voltage in an inductive load (like a motor or compressor) will increase the current. That is actually generally a myth; many people believe this myth because the current drop is NOT proportional, unlike in resistive loads. The resistance that shows up in a motor is called inductive reactance, which is an opposing magnetic field that creates back electromotive force (back EMF) and impedes the circuit. Back EMF and inductive reactance contribute to the impedance or total resistance of the circuit. Decreasing the voltage may cause the resistance to increase, as some of the work will start contributing to heat instead of mechanical motion; the motor derates, becomes less efficient, and draws more current than it needs, but it doesn't actually draw more total current. However, some variable-speed motors on VFDs may draw more current because the motor module speeds up the motor to make up for the voltage deficiency, static pressure, etc. ECMs also fall into this category and may draw more current if the motor module or VFD calls for it. However, in terms of simple electrical math without VFD logic, the current won't typically increase if the voltage drops, even in inductive loads. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Alex Meaney returns to the podcast to explain why it REALLY gets hot upstairs and what we can do about it. He also talks a bit about his new business. Heat technically doesn't rise; warm air is less dense than cooler air, so cooler air sinks as warmer air rises. In many cases, people blame stratification and the stack effect for warm upstairs areas, but there may actually be other issues at play, especially if the issue only seems to happen in the summer. Many apparent convective problems are actually due to building science errors, especially poor insulation when walls are exposed to attic space. When air moves via convection, it brings the heat it contains with it, which can contribute to comfort problems. To help figure out what is going on, try to see what the floor temperature is; a cold floor usually indicates a building design mistake, particularly a joist bag problem. Some of the solutions that may sound good aren't actually that effective, including placing return ducts higher. In many cases, we have to think about fixing the actual building, not the HVAC system. Some attics that are poorly ventilated and insulated will need to be reinforced. Alex and Bryan also discuss: Mean HVAC Consulting & Design Wind washing and exposure within the insulation R-value Pressurization and how it relates to hot air "rising" Manual J and its shortcomings with significant heat gains/losses Duct design and using a Ductulator Soffit vents, ridge vents, blown-in insulation, and infiltration Why building science skills are important for HVAC technicians Poorly conceived home designs Diagnostic tips and tricks Vapor-permeable air barriers Sizing, capacity, and power consumption Learn more about what Alex is doing at meanhvac.com. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast, Bryan busts the common electrical myth that single-phase 240v power is really two-phase power. When power goes into a structure that runs 240v appliances, we may understand that two 120v sine waves are 180 degrees out of phase with each other, but that isn't 100% accurate. If we were to use an oscilloscope to watch the electrical sine waves, we would see two sine waves 180 degrees out of phase because the transformers are center-tapped. Center-tapping creates a neutral center point that becomes our reference. The transformer has two sides: a primary and a secondary. The number of wraps on each side is proportional to the other, and the number of wraps also dictates whether a transformer steps the voltage up or down. However, when you use the center tap as a reference, that also makes the voltage appear to be halved. In many residential structures, a single phase of power goes into the transformer from the power company. If you were to use the center tap as your reference on each side of that transformer, you would read 120v; the two 120v readings add up to 240v. However, if you were to use the other side as the reference (as in a corner-tapped transformer), you would read 240v. On an oscilloscope, you would see the same thing; using the center tap as the reference, you would see two 120v sine waves completely opposite each other. If you were to measure completely across the transformer, however, you would see a single 240v wave, which is larger. Remember: only one phase comes from the power company. We only appear to get two separate waves because of our available point of reference. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Moe Hirsch joins the podcast to discuss the hydronics side of the industry, particularly focusing on Dan Holohan's Pumping Away and exciting developments in the hydronics market, especially regarding electrification. Pumping Away is many people's entry point to hydronics. It contains some good basic information about boilers, especially when it comes to learning about the pressures involved in pumping and how the components manipulate pressure throughout the system. Boilers use many of the same fundamentals as compression-refrigeration HVAC systems; pressure drops are similar, as are phase changes in steam boilers. Boilers also employ pumps instead of compressors, but the processes are similar. The pump or circulator makes a pressure differential within the boiler, which adds pressure to the circulator outlet and results in negative pressure on the suction side. However, problems like air bubbles and magnetite buildup can negatively impact performance. The electrification side of the boiler industry is exciting, especially because of the relative safety of electricity compared to combustible fossil fuels. However, electrification comes with its own set of concerns, especially when natural gas prices are low. In some markets, electrical grids also haven't caught up with the demand for electricity yet. Moe and Bryan also discuss: Moe's recent work in the industry Changes in boiler infrastructure over the years Pumping away from the boiler vs. pumping at the boiler Pressure's role in boiler systems Similarities between parallel racks and boilers Challenges with ECM circulators Evolution of boiler motors and controls Magnetic and hydraulic circulation Low-temperature heat pumps with radiant heated systems Moe's ideal HVAC system Natural gas health and safety risks (carbon monoxide) To learn more about what Moe is doing, check out turnupthecomfort.com or contact Moe directly at [email protected]. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast, Bryan busts the myth that hard starts reduce the start current on the run winding of a compressor. A single-phase motor's main winding is the run winding; it has a lower resistance and a higher current than the auxiliary winding, also known as the start winding. Hard start kits are often used on HVAC systems with single-phase compressors (which usually have PSC motors). These kits usually consist of a start capacitor and a potential relay, which takes the start capacitor out of the circuit. We don't typically use hard starts on three-phase motors or ECMs. Single-phase compressors often have to start under a big load, especially in long-line applications (at the manufacturer's recommendation) or if the compressor simply has a hard time starting. In cases where you have a voltage drop or low voltage, particularly due to long branch circuits, you may also use a hard start kit. However, they do NOT reduce the starting current or "save" compressors. Hard starts reduce the time-averaged starting current because they get the compressor to start up more quickly (therefore, the starting current is higher for a shorter time). However, hard starts do NOT reduce the spike of current upon startup. Like run capacitors, hard start kits allow current to flow on the start winding, but the run winding current stays the same. Hard start kits boost the start winding current faster, not at a lower current, reducing how long the system is in locked rotor. If they stay in the circuit too long, they could overheat the start winding and need to be taken out. Therefore, we don't want to use hard start kits without careful consideration. Soft starts are different entirely; they CAN reduce starting current. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Andy Holt joins the podcast to talk about what it means to be a 24-Hour Technician. We talk about what it means to be HVAC/R technicians AND deal with the human aspects of our lives at the same time. Service technicians differ from installers in that they do much of their work solitarily. They spend a lot of time by themselves. They're also on their feet very often and may do emotionally exhausting work, but they can earn a respectable living and accumulate savings for the future. To make our work and the emotional burdens that come with it more manageable, we can try to control how we react—take out head trash. Most people—but especially technicians—experience anxiety, and worrying about things takes a major toll on us. We also may need to apologize to people who we simply can't access. Andy goes over some of his best tips for dealing with those sources of worry. The goal is to eliminate negativity—clearing up negative aspects of your life and not being weighed down by individuals who negatively affect your life. As technicians, we do a lot of work to help other people, and the opportunities are endless for us. Customers may not always understand the value of the work we do, but we can bring positive experiences to them. We can find a lot of fulfillment in our work that way and bring positivity to our own lives. Andy and Bryan also discuss: Replacing negative thoughts with more positive ones The power of handshakes and eye contact Carrying burdens and being kind Apologies and forgiveness How to apologize to inaccessible people Being a "24-Hour person" Using overtime to avoid our lives outside of work How to manage anxiety Casting a future Andy Holt's Outdoor University To get in touch with Andy, visit https://toprate.com/ or call (706)-888-2332. You can also email Andy at [email protected]. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Jim Bergmann returns to the podcast to talk about furnace commissioning procedures and the development of measureQuick 2.0. MeasureQuick 2.0 has been a collaborative effort between Jim Bergmann and Joe Medosch, and it comes with an upgraded user interface that allows for faster operation and easier system data access and storage, and it works with more tool manufacturers' tools. Gas furnaces need to be commissioned to reach their maximum potential (and lifespan). MeasureQuick 2.0 provides commissioning instructions and recommends starting with a visual inspection, including the flame rectification system (rod, circuit board, and grounding). Electricity is conducted during the flame rectification process—only in the microamp scale—so a dedicated circuit is crucial to keep it working as it should. When commissioning a high-efficiency furnace, we should make sure the condensate drain cannot become clogged. The filter should block the airstream completely and not allow for any bypass, which could make the secondary heat exchanger, condensate drain, or circuit board dirty. The combustion air zone (CAZ) is also important; we don't want contaminants in there, as those could create acids that rot out your furnace components. Jim has also recently worked with the folks at TEC to make MeasureQuick 2.0 compatible with the TrueFlow grid and DG8. This integration allows you to identify airflow issues much more quickly and easily than before. MeasureQuick 2.0 also stores a lot more historical data, especially as it relates to the built-in visual inspection checklist. Jim and Bryan also discuss: The history and methodology of measureQuick 2.0 What technicians tend to miss the most Furnace circuit boards Electrical signals and flame rectification Filtration best practices IAQ accessories and pressure drop Combustion air zone (CAZ) Evolution of airflow measurement with measureQuick Venting termination considerations Clocking the meter and setting the fuel pressure CO and CO air-free PPM Low-level CO protection Checking manifold and inlet pressure Is the industry ready for universal heat pumps? If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Mike Klokus and Jeff Crable walk us through Kalos Services' light commercial PM process. First, we verify that everyone is clear on the agreement. Then, we start the PM with a thorough visual inspection, taking copious notes about things that look concerning. Once we've done a visual inspection, we clean the condensers. We try to use only water when possible, though safe cleaners may be necessary in some cases. When checking the electrical components, we make sure the wires are neat and have tight connections. We take our electrical readings and check the capacitor. Then, we check the system's refrigerant temperatures and pressures. We measure the superheat, subcooling, and pressures throughout the system and record those. Once we move indoors, we check and replace the filter in accordance with the agreement. We do another visual inspection at the air handler, paying special attention to blower wheel cleanliness, panel insulation, and wire routing and connections. When cleaning the evaporator, we want to try to stick with water or self-rinse cleaners. We want to make sure that we use very mild chemicals, and any foaming cleaners should be diluted appropriately and rinsed entirely. Drain cleaning is one of the most critical parts of a PM. We check for double traps and to make sure that the drain lines are properly pitched, trapped, and vented; vents should be uncapped, but cleanouts must be capped. We finish with a final inspection, making sure all disconnects are back in, cleaning up all trash and tools, and sharing any notes with the customer. Mike and Jeff also cover: Cleaning microchannel and multi-row coils Critical electrical readings How to replace panels carefully Filter replacement Modifying ductwork and return boxes for accessibility Cleaning drain pans thoroughly Pulling and cleaning blower wheels Common drains and condensate pumps Traps, cleanouts, and vents Testing heat strips Finishing up calls If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast, Bryan covers a common electrical myth about wire length and its relationship with the National Electrical Code. The NEC is concerned with safety—protecting buildings and people—but less so with making sure things work. Wire sizing is a common topic, and length is important because it can contribute to the voltage drop in a circuit. In many cases, we refer to the MCA (minimum circuit ampacity) to select an appropriate wire size. If you run more current through an undersized conductor, it gets hotter and will experience a voltage drop—though not proportionally. It's worth noting that nothing in the circuit is fixed; voltage, amperage, and resistance all follow Ohm's law but are variable as different things start happening in a circuit. In many cases, the NEC generally doesn't require us to size conductors to accommodate for voltage drop. Conductors have some degree of resistance, so longer wires will result in a greater voltage drop than you would see in a shorter wire. It makes sense for the wire to overheat, but that won't happen because the greater resistance in the circuit will reduce the current. There is less work being done. Longer wires and circuits that are sized correctly shouldn't overheat or present a safety issue. The NEC recommends but does not require voltage drop to stay below 5% across a conductor. That is a performance recommendation, not a safety concern. We need equipment to perform correctly, but NEC won't prevent electricians from setting up branch circuits that are longer than the ideal length. Excessively long branch circuits are common in commercial structures, and it's up to HVAC technicians to notice that and measure the voltage drop to make sure it's not negatively affecting the equipment. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Trevor Matthews, the founder of Refrigeration Mentor, returns to the podcast to talk about why CO2 matters in commercial refrigeration and even HVAC applications. CO2 (R-744) has entered the residential HVAC sphere in some places around the world, though it hasn't come to the North American markets yet. CO2 is one of the most eco-friendly refrigerants on the market, with a GWP of 1, and it's very good at moving heat. However, CO2 has some challenges, including its low critical point and higher pressures. CO2 comes with some safety concerns, and its systems have a complicated infrastructure. Since CO2 can exist as a liquid, vapor, or solid under operating conditions, you could end up with dry ice in the system. These issues require skilled, attentive technicians. As the industry moves to natural refrigerants like CO2 and hydrocarbons, we need to stop the race to the bottom. Technicians need to learn how to take their time and do the job right when they work on CO2 equipment so that they can be safe and save energy. The future of troubleshooting will eventually lie in electronic controls that take measurements constantly. Technicians won't lose their necessity with these changes, but it will be easier for them to respond to those measurements directly without connecting gauges. Technicians will also be able to access performance logs, which can help diagnose long-term problems. Trevor and Bryan also discuss: Trevor's history working with CO2 Refrigerant regulations Transcritical CO2 and climate The skills and proficiency of young technicians Dry ice in CO2 systems Pressure transducers and pressure release valves Manufacturer support and quality control Data logging and electronic controls in commercial refrigeration Trevor's recommended resources for CO2 education and training Check out Trevor's mentorship and training initiative at refrigerationmentor.com. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

This podcast is Bryan's full-length electrical basics class for the Kalos technicians. He covers electrical theory and circuit basics. Volts, resistance, and amps all affect the behavior of electricity in circuits. These are also critical factors in electrical safety. Watts and kilowatts come from the multiplication of the volts and amps, though not every volt-amp does work; the power factor indicates how much work the volt-amps are actually doing. Some of the volt-amps are reactive (kVAR) and don't do the real power of watts. Electrons move by interacting with other atoms. Substances can be conductors or insulators, and conductors have very few valence electrons, which move in and out of other atoms easily. Insulators have many valence electrons and are more stable. Insulators have high resistance, and conductors tend to have low resistance. Circuits consist of loads, switches, and power supplies. Loads actually do things and consist of light bulbs and motors. Switches pass power and don't do work. Power supplies can be finite, like batteries, but also include transformers that take power from the utility company. Open circuits don't move electricity, but closed circuits create a complete path that allows electrons to move. Electricity takes all available paths, not just the path of least resistance. Bryan also covers: Electricity and the body GFCIs and AFCIs Shock and arc flash protection Lockout/tagout Electricity and fall hazards Energy transfer Resistive vs. inductive loads Magnetism and flux Direct current (DC) vs. alternating current (AC) How power companies and generators work Open vs. short circuits "Path of least resistance" Tripping breakers Electrical units of measurement Step-up and step-down transformers Electrical frequency (hertz) Variable frequency drives (VFDs) Microfarads and capacitors Parallel and series circuits Becoming more proficient at reading diagrams If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast, Bryan debunks the myth that electricity only takes the path of least resistance. It is true that more current will typically take paths of lower resistance; it's much easier for more electrons to flow through a path with lower resistance, which is consistent with Ohm's law. Ohm's law states that a circuit will have higher current with you have lower resistance so long as the voltage stays the same. In most cases, the voltage stays relatively constant; transformers don't often need to limit their currents, so there usually isn't a voltage drop. When power supplies are regulated, the voltage is usually fixed, not the amperage. As a result, dropping the resistance in a circuit will increase the current. Ohm's law holds true for both resistive and inductive loads. Inductive loads, however, are a bit tricky because the resistance isn't constant. As motors spin faster, they create back EMF or impedance, which is magnetic resistance. The resistance only shows up once a motor, solenoid, or another electromagnetic component is energized; the resistance is much more dynamic. An electrical current takes ALL parallel paths, not just the path of least resistance. The current also stays proportional to the resistance, even when it takes paths of many different resistance values. Our bodies are also parallel paths, so there's a risk of electric shock even though our bodies usually have much higher resistance than loads. Wet skin has less resistance than dry skin, so that's why electricity and water are so dangerous to us; lower resistance means that more current can flow through our bodies. If electricity ONLY took the path of least resistance, we wouldn't be able to operate all the appliances and electrical components in our homes. The only prerequisite is an electrical potential (voltage). If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Nikki Krueger from Santa Fe Dehumidifiers returns to the podcast to talk about dehumidification equipment and strategies in the shoulder seasons (spring and fall). The shoulder seasons (and the weeks leading up to them) are when many homeowners begin to notice moisture problems in their homes. HVAC units and dehumidifiers should have a king-queen relationship. The HVAC unit is the king and controls the bulk of temperature and humidity during the day, but the dehumidifier can take care of the humidity when the king needs help. To remove moisture optimally, an HVAC unit needs longer runtimes and a cold evaporator coil. However, there will still likely be gaps in performance, and that's when the dehumidifier can step in. Proper equipment sizing can help us achieve better runtimes; we want to avoid oversizing the HVAC equipment, but oversizing is a bit less critical when it comes to installing dehumidifiers. The actual install configuration is more important when it comes to dehumidifiers (i.e., whether it takes supply or return air and ties into the supply or return). Dehumidification can be coupled with ventilation and filtration; ventilating dehumidifiers bring in outdoor air and should filter it before dehumidifying. The air mixing tends to occur in the dehumidifier, and the mixed, dehumidified air then moves into the supply airstream. Nikki and Bryan also discuss: Condensating vents, walls, and equipment Modern homes, energy efficiency, and HVAC Infiltration and the building envelope's effect on humidity Effects of equipment sizing and wall/duct insulation Fan speed, air mixing, condensation, and humidity Andy Ask and Ken Gehring's contributions and legacies Humidity from household habits and behaviors Santa Fe Oasis 105 features and operation If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast episode, Bryan gives some quick tips for time management. You can save a lot of time by prioritizing what really matters and delegating tasks. One of the simplest but most effective ways to manage your time is to use a calendar. You can even apply the calendar to your personal life; you can get into a habit of scheduling important appointments, deadlines, and tasks. Google Calendar also allows other people to see and interact with your schedule, so it's a great tool for scheduling performance reviews, interviews, and meetings. When you prioritize things, think about the negative and positive impacts of each thing. The ones with the highest positive and negative impacts should take priority over things with less significant positive or negative impacts. Many of the major business initiatives take place in the slow season, and many of our urgent client issues take priority during the busy seasons. Delegating is also a critical task. Just because you can do something, that doesn't mean you should do it. So, it often makes more sense to give someone a task if they're uniquely qualified for it. If someone is uniquely qualified to do a task, then you can delegate that task to them. Delegating is NOT the same as passing work to someone else because you don't want to do it. To delegate effectively, you need to assess qualifications and prioritize. On the management side, you can put processes in place that allow you to spend less time managing and more time doing meaningful things at work that you actually enjoy. Making videos and audio tutorials can make it easy to demonstrate processes and procedures within your company. Then, you can focus on leading by example, creating, and making everybody better overall. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Eric Kaiser returns to the podcast to talk about how to become a better mentor. He explains the topic from the perspective of a mentor and a mentee. The goal of mentorship is to pass your knowledge on to someone else. When you give someone the knowledge to succeed in the HVAC/R trade, you move the trade forward and allow yourself to try new career opportunities when someone can replace you. Some of the most effective mentorship strategies establish the mentor as a guide rather than someone who spoon-feeds the mentee. Mentorship is about supporting discovery, which also builds the relationship between the mentor and mentee. Mentors can also learn from their mentees when they allow their mentees to discover the answers to their questions. Mentors can also benefit their mentees by talking about health, especially mental health. Those who have been in the trade a long time may know how to draw boundaries between their work and their personal lives; mentees can benefit from open discussions about those things, and it helps to know that their mentor cares for them. Good mentors help mentees prioritize their health and wellness and break mental health stigmas. Mentors can also share references to other possible teachers with their mentees. Those relationships are especially important for mentors who don't have all the answers. Mentorship provides the context for training, and those connections provide as much context as possible. Mentors can also be mentees themselves, and those relationships are what really advance the trade. Eric and Bryan also discuss: Online education vs. in-person mentorship The role of the apprentice or mentee The Socratic method Mentoring people about health and safety practices Bryan and Eric's mentors Recognizing who mentors are and treating them appropriately If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Eric Kaiser joins the HVAC School podcast to talk about HVAC measurement types and the benefits of taking each one. He also talks about point measurements and data trends. Point measurements include static pressure, voltage readings, and readings provided by gauges. We only take those measurements once. However, when you track those on several occasions over time, you can build data trends. Single-point measurements give us information about what is happening at the moment, but they don't give us a long-term view of the system's health. Absolute and differential measurements also have different purposes entirely. Absolute measurements require us to compare a reading to a specific, unchanging reference point, but differentials compare one measurement to another. When we turn point measurements into trend measurements, we can see some degree of causation. Changes in data trends indicate that a problem occurred at a certain point in time and could be due to changes that coincided with the deviation from the norm. However, that's intermittent trending that relies on us to take point measurements at spaced-out points in time. Continuous trending allows us to use sensors and test instruments that map changes constantly. At the end of the day, point measurements are like snapshots, and continuous data trends are like videos; the former only shows part of the picture, and the latter can help us solve more difficult problems by giving us a more complete idea of what's happening. Eric and Bryan also discuss: Qualitative vs. quantitative measurements Filter restrictions and static pressure Gauge vs. atmospheric pressure Combined trend measurements How tool usage and calibration impact measurements Non-invasive testing Recorded data and sample frequency Comparative troubleshooting in spaces with similar equipment Resolution vs. accuracy vs. precision If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Genry Garcia joins the podcast to give an intro to ASHRAE Standard 62.2. He and Bryan also share a nice rant about accountability in HVAC design. Standard 62.2 is the ventilation standard for low-rise residential buildings, which dilutes airborne contaminants like VOCs and CO2. Before coming up with a ventilation strategy, we need to assess the leakage rate of the building, such as via a blower door test. However, we also need to consider how bringing in outdoor air might negatively affect efficiency and comfort if we don't do it right. Exhaust ventilation removes air from the structure and relies on infiltration to bring air back in. Instead, we can use controlled intake air, which is brought in from the outdoors instead of unconditioned spaces in the home. Ventilating dehumidification is a strategy we can use to comply with 62.2; we can bring in filtered outdoor air and dehumidify it before injecting it into the supply ductwork. When we introduce ventilation in a Florida installation, bringing it in through the return is typically not ideal, especially if it's unfiltered. People can go wrong with 62.2 if they remain shortsighted; when designing ventilation systems, we need to think about a lot more than the load calculations and CFM of fresh air needed. We need to focus on accessibility, ventilation strategies, and location-specific installation practices. Consulting tradespeople during the design process would likely make ventilation systems much more accessible, sensible, and effective. Genry and Bryan also discuss: Ventilation as an IAQ strategy Infiltration credits Pressurization Continuous vs. spot measurement Holding the right people accountable during the design phase Intermittent vs. continuous ventilation Automating ventilation with sensors Controlling ventilation on a timer Genry's ideal methods of controlling ventilation If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

RACT manual co-author Eugene Silberstein joins the podcast to talk about the titular topic of his book, Pressure Enthalpy Without Tears. Pressure Enthalpy Without Tears is a book that introduces engineering concepts to HVAC technicians in a way they can understand and apply in the field. Enthalpy is a fancy way of saying "heat," and we use it to refer to the total heat content (BTUs). The pressure-enthalpy chart shows the relationship between the refrigerant pressure and enthalpy in a system; it's like a P-T chart that shows the relationship between heat content instead of temperature. Each refrigerant has its own pressure-enthalpy chart, but the points and lines on the chart usually form a right trapezoid. Dirty air filters and other less-than-ideal conditions can distort the trapezoid or shift it on the chart. Each side of the trapezoid represents the refrigerant inside a major component of the HVAC system: evaporator, compressor, condenser, and metering device. The pressure-enthalpy diagram allows you to get a look at individual components while keeping the entire system in mind. To plot points on a pressure-enthalpy chart, you need the high side pressure, low side pressure, condenser outlet temperature, evaporator outlet temperature, and compressor inlet temperature. Pressure is usually measured in absolute units (rather than gauge units), but ballpark estimates are typically sufficient. Entropy is another concept we need to consider. Compression theoretically leaves no additional entropy and is reversible. Crossing a line of entropy means that a process is no longer reversible. Eugene and Bryan also discuss: Technicians vs. engineers Temperature vs. heat content Psychrometric and pressure-enthalpy charts Using the pressure-enthalpy diagram to assess operation costs Electrical measurements Predicting compressor failure Putting passion into learning and trades education You can visit https://www.escogroup.org/ to purchase Pressure Enthalpy Without Tears and access all of ESCO Group's resources. You can also use the code HVACSchool22 for a discount on ESCO Group's eLearning services. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast, Bryan talks about THOR, total heat of rejection. He explains what it is and why we should care about it when working on HVAC/R systems. THOR is another aspect of pressure-enthalpy calculations, along with net refrigeration effect (NRE) and total heat of compression. When we talk about system capacity, we're often referring to heat absorbed in the evaporator coil (NRE). Heating is on the opposite side of the coin; when we bring heat into a home, we care more about how much heat is rejected than absorbed. That's where THOR comes in. More heat is rejected at the condenser than absorbed in the evaporator. The total heat content increases due to additional heat being absorbed in the suction line. Compressors also have motors that aren't 100% efficient, so a bit of inefficiency also adds a small amount of heat to the refrigerant (in a system operating normally). All of that heat adds up to the total heat of rejection (THOR). Even though a higher total heat of rejection is desirable when we want heat pumps to bring heat into the home, we don't want our compression ratios and discharge temperatures to get too high. We have to avoid oil breakdown and other negative effects. So, modern heat pumps use variable frequency drive technologies or liquid or vapor injection to get a lot of capacity out of the compressor without overheating it. The effective THOR only happens in the condenser. Some heat rejection may occur in the discharge line, but none of that is of use to us when we need to bring heat indoors. Check out Eugene Silberstein's book, Pressure Enthalpy Without Tears, at https://escogroup.org/shop/itemdetail.aspx?ID=1445. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Matteo Giovanetti from Micro-Air joins the HVAC School podcast to talk about the differences between a hard start and an EasyStart. Micro-Air's "EasyStart" provides a soft start rather than a hard start. A hard start abruptly ramps up the voltage and current to the motor start; a soft start is a much gentler start that results from a gradual voltage and current increase on the start AND run windings. The EasyStart marks a paradigm shift in how we think about "saving" compressors. It attempts to avoid drawing unnecessary inrush current, which is very common with hard starts. Hard starts may even lead to premature failure if the potential relay fails and can't take the start capacitor out of the circuit. EasyStart has a different wiring configuration compared to hard start kits. A hard start kit consists of a start capacitor wired in series with a potential relay, which increases the torque on the compressor and removes the start capacitor from the circuit. The EasyStart has four wires; the black and white wires (L1 and L2) connect directly to the contactor, a brown wire that splices directly to the run winding, and an orange wire to the HERM terminal of the run capacitor. EasyStart also records information about the compressor during the first few startups to optimize its performance. It also monitors overcurrent and fault conditions with phase detection; when it detects a stall, it shuts off the compressor and doesn't attempt to restart it until a few minutes have passed. Matteo and Bryan also discuss: EasyStart models Solar, generator, and RV use Impedance Positive temperature coefficient resistors (PTCRs) Compressors running backward EasyStart's Bluetooth capabilities Tech support and product education Offering useful upgrades to customers Running and starting watt specifications for generators Learn more about EasyStart or purchase it directly from https://www.microair.net/. You can also contact the manufacturer by email at [email protected]. You can view the EasyStart home installation video at https://www.youtube.com/watch?v=bp4U-husy1o&ab_channel=MicroAir. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast, Bryan explains what the heat of compression is and why we should care about it as HVAC/R professionals. More heat is rejected in the condenser than absorbed in the evaporator coil, and that's because the compressor adds heat. That added heat is called "heat of compression." That heat does NOT contribute to the net refrigeration effect (NRE), as it doesn't contribute to cooling. When we compress something, we increase the system entropy during that process. Entropy is the waste and disorder associated with work. There is some inefficiency, which we see in the form of additional heat. So, the HVAC system needs to reject that additional heat of compression, and we can plot and track reversible changes by following lines of constant entropy. As the temperature increases, the molecules begin moving more quickly. However, the refrigerant doesn't absorb many more BTUs in the compressor (in a properly operating system). The temperature spikes, but the compressor doesn't typically add a significant number of BTUs to the refrigerant. Heat also enters the system via the suction line, which also doesn't contribute to the NRE. Long, uninsulated suction lines can absorb a lot of heat without cooling the space at all. That heat also has to be rejected in the condenser. So, short, well-insulated suction lines tend to absorb less heat. When plotting the heat of compression, we're looking at BTUs added into the system in the compressor, discharge line, and suction line. BTUs that don't contribute to the NRE may fall under the "heat of compression" label, though the actual definition may vary by organization. Check out Eugene Silberstein's book, Pressure Enthalpy Without Tears, at https://escogroup.org/shop/itemdetail.aspx?ID=1445. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Ed Janowiak joins the podcast to introduce us to ACCA Manual T. Compared to other manuals, Manual T is one of the least-considered ACCA manuals. However, it's the manual that advises us on how not to blow high-velocity air on people and has maintained the same standards since the mid-1900s. Unlike Manuals J, S, and D, Manual T is not recognized in code compliance. Manual T deals with air distribution; it helps us find out the throw and spread, which informs our ductwork design in Manual D. We need to know the customer's expectations and the air velocity we'll need to manage at the registers before designing the ductwork. Register placement is also a critical element of Manual T. Throw and spreqd can vary wildly, and register selection and placement are going to have a significant effect on comfort as a result. Register placement on the ceiling may achieve the Coanda effect to assist with air distribution, and that can be especially useful in low-load or passive homes. Low-load homes are an interesting case, as they use less hardware than other homes, meaning that we need to make the most of calculations and equipment selection. Manual T ultimately focuses on using the diffusers and registers, rather than the equipment, to spread air throughout a space. Knowledge of the principles in Manual T also allows us to communicate, establish, and manage expectations with the customer. Ed and Bryan also discuss: Registers, diffusers, grilles, and vents Filter restrictions ACCA Manual LLH Air movement in the occupied vs. unoccupied zone Manual T as an extension of Manual D What it means to lend credibility in this industry Floor vs. ceiling registers based on climate If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast, Bryan explains what the net refrigeration effect (NRE) is and how it affects HVAC systems. The net refrigeration effect (NRE) is what happens in the evaporator coil. The evaporator is the heat absorber; as air passes over the coil, the cooler refrigerant within the evaporator absorbs that heat and boils. The NRE is the net energy change that occurs during that process. You can plot the NRE on a pressure-enthalpy chart. When air moves over the evaporator coil, there is a change in enthalpy or BTUs per pound in the refrigerant (usually called delta h). There should be more BTUs per pound in refrigerant exiting the coil than when it went in. We have to know how many pounds of refrigerant we're circulating (mass flow rate) and how many BTUs are in those pounds. Many of those BTUs come from latent heat transfer, which happens when the refrigerant boils. When refrigerant undergoes a phase change, it remains at a constant temperature (sensible heat), but it continues absorbing heat. The heat absorbed contributes to the phase change, and that's latent heat. Most of the NRE deals with those latent BTUs. (Note: this does NOT refer to latent heat loads.) In addition to the boiling or saturation phase, we also have to consider BTU changes when refrigerant flashes off at the beginning of the evaporator coil and heat obtained during the superheating phase at the top of the coil. We can maximize our NRE by running a cold evaporator coil (without freezing) and ensuring the evaporator is full of boiling refrigerant. BTUs absorbed in the suction line do NOT count towards the NRE, as they don't contribute to cooling spaces or refrigerated boxes. Check out Eugene Silberstein's book, Pressure Enthalpy Without Tears, at https://escogroup.org/shop/itemdetail.aspx?ID=1445. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Eric Kaiser returns to the podcast to talk about how we can use systems thinking to approach gas appliances and combustion in HVAC installation and service. Gas lines can be made of a few different materials, including black iron, copper, and CSST. These all have benefits, setbacks, and appropriate applications. For example, copper is common in propane (LP) systems but not natural gas. In coastal environments, galvanized pipe tends to be most common due to the increased likelihood of corrosion. Gas lines may also need sleeves to prevent them from interacting with moisture. The piping also needs to be routed in accordance with code; in many cases, joints need to be exposed so that a technician can check for leaks. Keeping joints inside walls is risky, especially when light switches cause sparks and could potentially ignite leaking natural gas. In any case, leak detection can be tricky unless you have a combustible gas leak detector and bubbles that work well for gas lines. Safety has to be the top priority when it comes to venting, especially on water heaters. A personal low-level CO monitor can also keep you and your customers safe by detecting small yet harmful amounts of carbon monoxide. Makeup air and combustion air are also important in gas appliances; unbalanced pressures may result in undesigned return paths. Traps and improper pitch may also lead to improper venting, as condensate may get trapped in the pipe and may lead to freezing or other complications. Eric and Bryan also discuss: Pipe material and flow rate Pipe sizing and connectors Regulator issues on gas water heaters and pool heaters Thread sealant products and best practices Bubble solution recommendations Signs and risks of backdrafting Exhaust pipe insulation Drain installation If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Some admins from the HVAC School Facebook group join the podcast to discuss the art of moderating a successful community. Bryan is joined by Eric Kaiser, Ty Branaman, Michael Housh, and Neil Comparetto. A community based on a skilled trade gives people an inviting space to share information and ask questions. It's also a space that allows people to practice how they present information. Groups also connect people across geographical locations, and we can get regional perspectives that change the way we think about things. However, community standards are necessary to keep groups professional and on-topic. Swearing is a slippery slope that may lead to personal attacks, which make the community hostile and unhelpful. The main goal is to keep a respectful atmosphere, and moderators have to draw the line somewhere, but there's a difference between cultivating a productive atmosphere and being dogmatic. People who interact in those communities need to do it for altruistic reasons, not to satisfy their egos. Giving detailed, accurate answers (ideally with a source to back up the information) is the best way to contribute meaningfully. Engaging in rigorous debates with an open mind is also a great way to see many different viewpoints. Debates in HVAC communities are great, but they require boundaries and mutual respect between debaters. Namecalling, blaming others, or dragging politics into the discussion is unproductive. Overall, it's best to stay positive and try to keep things helpful, and admins try to maintain an atmosphere that can be both serious and lighthearted but is always helpful and respectful. HVAC communities and groups are not places to share other groups, content, or job postings. These groups are not marketing centers; they are forums for learning and discussing the work we do every day. Ty, Neil, Michael, Eric, and Bryan also talk about: How they got started in online HVAC communities Unproductive arguments about codes Banning and muting members Receiving feedback Avoiding logical fallacies in debates How egos hold people back Trite and unproductive catchphrases, slogans, and jokes Responding to disagreements productively Communicating with people appropriately Admitting fault and refraining from judging others who are incorrect Moderating posts for quality and shareability If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Eric Kaiser returns to the podcast to discuss high-voltage wiring, low-voltage wiring, and condensate assemblies as they relate to systems thinking. On the high-voltage side, the disconnect should be in a secure location, and it should be able to keep water out. The wires should be appropriately sized, have an appropriate level of tension, and should not be vulnerable to chafing or abrasion. Overall, best practices include using proper grommets and ensuring that you have a solid connection. Do not run high voltage wiring in parallel with low-voltage or control wiring. It's also worth noting that double-lugging is a poor practice that is against code. On the low-voltage side, you also need to be careful of where you route your wires to avoid induction, contact with hot surfaces, or abrasion. The insulation ratings also need to be appropriate. We can think of the condensate assembly as its own system. Condensate drains have uphills and downhills, and they may have traps, vents, and cleanouts throughout. Cleanouts and vents may be confused for each other, but cleanouts allow the technician to access and clean the drain. Cleanouts are also capped when in use, but vents are not. The location of a vent can help equalize the siphoning effects of pressurization. Condensate systems also consist of pans and switches. In those cases, redundancy is desirable to prevent overflowing. Secondary drain pans should be large enough to overlap with the primary pan, especially in horizontal air handlers. Eric and Bryan also discuss: Conductor length best practices Connecting stranded to solid wire Lug torquing Variation in wire sizing Testing low-voltage wires Cleanout tees Single vs. multiple drains with other appliances Drain pitch and if there could be "too much fall" If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Eric Kaiser returns to the podcast to talk about how copper, piping, and line sets play into systems thinking. Nowadays, we have to think about POE and PVE oil, and we need to design line sets in a way that assists with oil carry while preventing liquid refrigerant migration. The height of the evaporator relative to the condenser is a major factor to consider during the design phase. Especially when chases are run underground, we need to watch for possible threats to the copper. Water softener discharge and excess pool water may damage the copper over time, and systems should be designed to keep line sets away from those. In many cases, Florida chases are sealed with mastic, which doesn't prevent water from getting in (but does prevent rodents and insects from entering the home. Flowing nitrogen is one of the best practices you can do while brazing. Nitrogen displaces oxygen, which contributes to oxidation and produces scale. When cutting copper, you will also want to make sure that you don't get copper shavings inside the tube. The pressure test is also an important step for leak detection. Following the manufacturer's instructions, pressurize the system and apply a liquid leak reactant (bubbles) to joints and other common leak points. It's a good idea to have at least one line drier in the system, and it should be able to work both ways in a heat pump system. Ideally, the line drier should be in a serviceable location, as it will be easier to detect restrictions when it's on the line set. Eric and Bryan also discuss: Air and vapor barriers Long line guidelines Underground chase depth Derate values Controversial reaming/deburring practices Line drier best practices If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Eric Kaiser joins the podcast to talk about systems thinking in HVAC. Systems thinking allows us to solve problems and address customers' comfort holistically instead of focusing on just the equipment. The key to systems thinking is to think outside the appliance. System design plays a major role in performance. Duct design, drain placement, and equipment placement all matter, and we can only do so much to mitigate factors of poor design. We need to assess the building envelope and consider how the HVAC system interacts with it. Building envelope and duct leakage will significantly affect HVAC performance and occupant comfort. Ventilation also matters, especially since many homes rely on exhaust-only ventilation. However, the air that leaves the building must be replaced, and we often don't control where that air comes from. When you control the source of your fresh air ventilation to meet ASHRAE 62.2, filtration may further help control the quality of the air that comes in. Installation and commissioning are other things we need to consider when thinking of the HVAC equipment systemically. The wiring needs to be correct, and we need to verify that the system is achieving the proper airflow in the first place. Static pressure is another factor that we must consider during commissioning, as an abnormal static pressure could indicate a filter that doesn't fit or is too restrictive. It's best to start by looking at the appliance and widening your scope from there until you know about the system as a whole. Eric and Bryan also discuss: Is the house a duct system? Oversizing equipment Stack effect Loose vs. tight houses Filtration best practices Radiant heat transfer Ductwork best practices Data trends of cause and effect If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Nathan Orr joins Bryan to talk about some logical fallacies, namely the false cause and strawman. They explain how those fallacies show up in the trade. It's difficult to present arguments without using fallacies, but people tend to rely on fallacies to uphold extreme religious or ideological viewpoints or conspiracy theories. Fallacies are also often easier to communicate than nuanced science and data. "False cause" relates to the phrase "correlation does not equal causation." It can be tempting to link coincidences and say that one thing causes the other, but that could very well not be true. For example, more compressors fail during lightning storms. It's reasonable to assume that lightning causes the failures, but lightning is not simply striking all of the compressors; other power outages and other conditions that happen during storms are more likely plausible causes. Confirmation bias also makes it easy to cling to a false cause. People are likely to disregard data that doesn't align with what they already believe. A strawman misrepresents (or deliberately misstates) another argument to make it easier to attack. People often apply the strawman fallacy to conversations about forming ice in a system during vacuum and duct sizing. Strawman arguments happen more often in business matters, especially if people impugn the intentions of the other party. In many cases, being open to new information will prevent you from falling prey to logical fallacies. Nathan and Bryan also discuss: Flat-earthers Inverter board failures at night Evaporator coil corrosion Simultaneous capacitor and fan motor failures Logical fallacies in chance and gambling The pitfalls of anecdotal evidence and small samples Appeal to emotion Defining "better" Mounting TXV bulbs Heuristics and mental shortcuts If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Refrigeration Mentor founder Trevor Matthews returns to the HVAC School podcast to talk about personal development and training, including tips for learning in HVAC/R. When you're looking at a problem in the field or in training, it pays to take a step back, cool down, and reevaluate your mindset. Trevor recommends thinking about the worst-case scenario and seeing how you can either prevent it or grow from it. It's good to walk away for a little bit anytime you feel like you're overanalyzing anything so that you don't make blunders. Trevor has found that reading books is one of the best ways to learn about HVAC/R. HVAC/R professionals can greatly benefit from investing in themselves and setting up their own self-directed training programs. Trainers and mentors can't be the only ones motivating HVAC/R professionals, holding them accountable, and stimulating their growth. Many times, our own limiting beliefs of ourselves hold us back, and we need to convince ourselves that we can learn difficult things, even if it isn't easy. We can also limit our ratio of entertainment to education; focusing more on the latter can greatly benefit your personal development. Setting educational goals is also difficult when we work long hours and simply don't have the time or energy to invest in ourselves. The industry needs reform, and reform that raises base rates and prevents an over-reliance on overtime might also attract some new professionals to the field. Trevor and Bryan also discuss: Trevor's new podcast Clearing your head Books about doing the hard things first Autodidactism and "learning how to learn" Subconscious cost-benefit analysis The industry's addiction to overtime Helpful books and podcasts for personal development Getting rid of "tunnel vision" Recommended book/podcast list: Eat That Frog!: 21 Great Ways to Stop Procrastinating and Get More Done in Less Time by Brian Tracy How to Win Friends & Influence People by Dale Carnegie QBQ! The Question Behind the Question: Practicing Personal Accountability at Work and in Life by John G. Miller Mindset: The New Psychology of Success by Carol S. Dweck Grit: The Power of Passion and Perseverance by Angela Duckworth Mastery by Robert Greene Good to Great: Why Some Companies Make the Leap and Others Don't by Jim Collins Built to Last: Successful Habits of Visionary Companies by Jim Collins Entreleadership: 20 Years of Practical Business Wisdom from the Trenches by Dave Ramsey Culture Code: The Secrets of Highly Successful Groups by Daniel Coyle Discipline Without Punishment: The Proven Strategy That Turns Problem Employees Into Superior Performers by Dick Grote Atomic Habits: An Easy & Proven Way to Build Good Habits & Break Bad Ones by James Clear Rich Dad Poor Dad: What the Rich Teach Their Kids About Money That the Poor and Middle Class Do Not! by Robert T. Kiyosaki The Richest Man in Babylon by George S. Clason The Big Short: Inside the Doomsday Machine by Michael Lewis Antifragile: Things That Gain from Disorder by Nassim Nicholas Taleb Think and Grow Rich by Napoleon Hill The 5 AM Miracle Podcast The Mindvalley Podcast Hidden Brain Podcast If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast episode, Bryan shares some of his top threaded connection tips. He also clears up some confusion about connection types. Threaded connections include flare and compression-type fittings (like chatleff or Aeroquip fittings). The threads don't actually make the seal; the pressure pushing the surfaces together is what makes a seal. Bryan doesn't recommend putting traditional thread locks on flares, but refrigerant oil or mild assembly lubricants can help the flare come together more smoothly without imperfections. However, you need to be careful when using a torque wrench and use the lowest acceptable specification to avoid over-torquing. Leaks are common problems with flare fittings, but those often happen in cases where flares are poorly made. Scored faces, loose flares, and over-torqued flares are common causes of leaks. However, many modern flaring tools can make perfect flares quite easily. You must also remember to deburr the copper for the best results. Compression-type fittings often have O-rings, which are the parts that actually do the sealing. (Leaks WILL happen without the O-ring in place.) You can use an assembly lubricant with these fittings, but you still have to be mindful of torque spec adjustments. Pipe-thread connections actually rely on the threads, not pressure or an O-ring, to create a seal. Pipe dopes (or thread sealants) tend to be best on these connections, but you want to leave the last couple of threads bare so that pipe dope doesn't get into the system. As with brazed and soldered joints, the copper used for threaded connections needs to be cleaned, cut squarely, and deburred for best results. Bryan also covers: Assembly lubricants Brazing vs. soldering Zoomlock IMC 1107.5.4 Protecting seals during brazing and soldering If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Bryan explains how parents and educators can succeed at giving kids the tools for any job they want. This podcast was originally a presentation at the 2022 FPEA Florida Homeschool Convention. Jobs, careers, and vocations have changed a lot over the years. Even though those have changed over the years, parents still want their kids' vocations to develop character, foster growth, and bring joy. While kids are young, parents can instill values of grit and diligence; however, parents have to overcome the challenges presented by the instant gratification provided by technology. Interest-guided learning is a double-edged sword, as it allows a child to pursue their interests but can cut them off from the interest of others. Developing the values of kindness and deference can temper the negative effects of interest-guided learning while maintaining the benefits of interest-guided learning. If a child has an interest in something and can pursue that interest on their own by demonstrating autodidactism, they open themself up to a lot of vocational options. Nowadays, it's a lot more common for people to hold many different jobs or vocations over their lifetime. Encouraging a child to learn different skills allows them to explore non-linear career paths more easily than children who don't learn useful skills. When teaching children, developing mental models and an appreciation for learning is another key to success across vocations. Bryan also talks about: Vocation vs. avocation Grit vs. talent in the pursuit of success Modeling and practicing gratefulness Transferable skills Feeling "stuck" in a vocation Visualizing average molecular velocity Learning about humidity and electrical movement Striking a balance between joy, service, and passion Expectations vs. standards Pursuing college, business ownership, and other career opportunities If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast episode, Bryan talks about ERV and HRV technologies, including their appropriate applications and limitations. HRVs are heat recovery ventilators (not to be confused with heat recovery units or HRUs), and ERVs are energy recovery ventilators. The main difference between these two lies in the type of heat they move; HRVs only move sensible BTUs, whereas ERVs move sensible and latent BTUs. As you bring air in from outside, you're discharging roughly the same amount of air (though modern technologies allow you to manipulate the pressure a bit more). The goal of the HRV or ERV is to recover some energy from the air exiting the structure and incorporate it into the incoming airstream. The airstreams cross over each other, and there is heat transfer but not air mixing. (ERVs also allow for the exchange of moisture.) Two fans drive the direction of energy flow, and a mesh or a porous desiccant medium facilitates the interaction between the airstreams. You will get some energy savings with an HRV or ERV, but savings are dictated by the amount of air moved and the temperature differential between the airstreams. In general, you will see HRVs up north (in low-humidity markets) and ERVs down south (in higher latent-heat markets). However, even ERVs aren't very effective in conditions with low energy transfer and high moisture UNLESS they're used with a ventilating dehumidifier. Bringing in fresh air is good for indoor health and safety, as it helps dilute the presence of VOCs, viruses, and harmful gases. HRVs and ERVs help us manage the air we bring in. Bryan also covers: Integrating ERVs with bathroom ventilation Safety considerations to consider for outdoor air Positive pressurization Demand ventilation with CO2 sensors Learning about ASHRAE 62.2 If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Rajan Rajendran and Jennifer Butsch from Emerson join the podcast to discuss the Helix and some refrigerant changes that are coming. Jennifer is the Director of Regulatory Affairs, and Rajan is the Global Vice President for Environmental Sustainability and former director of the Emerson Helix. Lately, there have been more environmental efforts to reduce greenhouse gas emissions, and plenty of large corporations have "net zero" initiatives. Sustainability requires a holistic, systemic approach in our industry; the Helix Innovation Center conducts the research needed for us to handle these sustainability initiatives as effectively and safely as possible. However, the sustainability initiatives frustrate a lot of technicians. There will likely be multiple refrigerant transitions as our industry progresses. Education and knowledge provided by manufacturers and HVAC organizations will be the key to smooth transitions. Many of the replacement refrigerants, including R-32 and R-454B, are A2Ls. These mildly flammable refrigerants have different handling, transportation, and charging procedures than what we're used to. However, we are unlikely to see changes in oils; POE and PVE oil will likely remain dominant in the market. Eventually, we may see more GWP changes. We would also be prudent to focus on preventing and rectifying equipment leaks. Proper maintenance will help us navigate current and possible future changes. Rajan, Jennifer, and Bryan also discuss: The AIM Act and HFC reduction in 2024 GWP-limit petitions in HVAC vs. refrigeration Refrigerants that manufacturers are embracing Refrigerant testing processes Natural refrigerants The weight of refrigerants vs. the weight of air Evaporator coil manufacturing and leakage Built-in leak detection Refrigerant pricing To learn more about these coming refrigerant changes, check out the AHRI Safe Refrigerant Transition Task Force's resources HERE or Emerson's E360 Platform HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast episode, Bryan talks about pilot controls. He talks about the old-school ignition systems on gas appliances and some similar pilot functions on residential A/C units and heat pumps. When we think about a pilot light on a gas appliance, we can think of it as a small standing flame that sits there ready to ignite the burner whenever gas is flowing. Pilot lights were necessary for old-school gas furnaces, and many of those pilot lights worked with a thermocouple. In many older furnaces, pilots also prevent excessive carbon monoxide from unspent gas. In other words, the pilot is not the main burner; it merely sets up the main burner. On a typical A/C system, the 24v power is similar to a pilot on a gas appliance; the 24v "pilot" control energizes the system and has a small amount of voltage (compared to the high voltage needed for all of the components to work). The reversing valve on heat pumps also has a pilot valve; the 24v signal activates the pilot valve with the solenoid, which redirects system pressure to allow discharge gas to slide the valve. That's also why you can't shift the operating mode when the system is off. Solenoid valves in general tend to have pilot functions; they rely on a refrigerant pressure differential that results from 24v electrical signals, not the signal itself. In short, we don't rely on the pilot light or the 24v electrical signal to power the entire equipment. Pilot controls merely help the equipment get started; they have less load on them and trigger or control parts and processes that are more complicated. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Bryan and Robert Orr continue their discussion about ethics by talking about what it means to have grit and discipline in business. They talk about what those characteristics look like in business and in life, and they mention some good books. Grit is a trait that can contribute to an ethical way of life; showing grit means that you follow through with a project until you get the results you want. Both physical and emotional grit are strengths, and those things tend to be more important than talent in our field. Compared to discipline, grit is a lot more closely intertwined with a person's emotional condition. When we encounter overwhelming negative emotions, grit is the quality that allows us to power through the current state of affairs. Discipline and grit are both based on commitment and resolve, but discipline deals more with actions rather than feelings. Discipline is more about habits, balance, and wisdom. A belief system or set of guidance is what drives discipline. Discipline can also be repetitious and boring, but it can take you farther than raw talent if you dedicate yourself to your belief system, sources of guidance, and goals. Developing discipline requires us to establish habits and sequence those habits. Good leaders and parents are the ones who establish those habits for employees or children. However, something to keep in mind is that both grit and discipline can amplify a person's bad characteristics. Robert and Bryan also discuss: Grit vs. talent (Angela Duckworth) Does grit count as an ethic? Discipline and delaying gratification Developing grit over time "Real" vs. "true" emotions and thoughts The downfalls of raw talent Thinking about obstacles in a healthy way If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Bryan and Robert Orr talk about ethics and what it means to have integrity when running a family business. Robert is a lifelong tradesman who is a licensed construction contractor, and he has overseen the construction side of Kalos for many years. Robert initially started off at the Air Force Academy and realized that he didn't feel that the military was right for him. While in Florida, Robert fell into the trades and learned both hard skills and ethics in the process. He started his own house-wiring business at age 21. Later, he went into home inspection and eventually started a business with his son (Bryan) and his brother-in-law (Keith) Kalos was co-founded by Bryan, Robert, and Keith, all of whom were tradesmen. Even when naming their business, they wanted to focus on ideals that extend beyond them and their individual legacies. They settled on the name "Kalos," which is the Greek word for "integrity." Having integrity in business is a lot more than just following rules and "having principles." Real integrity is authentic and honest; you're transparent about who you are and deliver on the promises you make. Integrity and customer service are NOT the same thing, but you tend to yield higher customer satisfaction if integrity is at the forefront of your business. Evaluating yourself is also a component of integrity: reflecting on your desires, confronting greed, caring for employees, and choosing to do the right thing. In many small businesses that haven't fully found their stride, integrity can be compromised by fear. Robert and Bryan also discuss: Christianity in business Integrity as it relates to pricing expectations What it means to be savvy Taking responsibility If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast, Bryan talks about distributors and external equalizers and why we need to use them together. When older Carrier heat pumps (with pistons) would run in heat mode, the metering device would be outside. In those cases, the port on the liquid line would be on the opposite side of the metering device. So, you wouldn't actually be measuring the liquid line pressure (high-side) if you measured it at that port while the system runs in heat mode. However, that pressure would be higher than the common suction pressure. That's because distributors and distributor tubes also have a pressure drop associated with them AFTER the metering device. Nowadays, TXV systems have external equalizers, which create an equalizing force inside the valve. The bulb pressure forces the valve open, and the equalizer pushes against that pressure to create a closing force. An internal equalizer would work fine on a system without a distributor or distributor tubes; however, those systems are few and far between. We need an external equalizer on systems with distributors because the pressure at the end of the evaporator coil is significantly lower than the pressure picked up by the valve. Without closing force, the TXV would theoretically force itself all the way open and flood the evaporator coil. External equalizers can get clogged, which results in a pressure buildup during the off cycle and forces the valve closed. They can sometimes get clogged when used on a Schrader port without a Schrader depressor inside the equalizer. Some people attempt to fabricate distributors in the field. It works in some cases, but in many cases, it's best to use an engineered distributor for the best performance and efficiency. The distributors are individually designed to create an individual pressure drop. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this short podcast episode, Bryan talks even more about sine waves and center-tapped transformers. Power is generated at the power plant when an energy source (such as steam) is used to drive a drive shaft. The resulting current can be mapped as sine waves, which actually represent points on a circle; there is a rotational magnetic field around stationary conductors, and the sine waves allow us to envision the positive and negative alternations as the rotation happens. Center-tapped transformers use "neutral" as a reference point. The secondary winding on a center-tapped transformer may have 240v power, but the center tap splits that 240v power into two legs of 120v power. There are two sine waves completely out of phase with each other, so we get 240v from peak to peak. Both sine waves cross at neutral. Even though the split-phase power consists of two separate sine waves, an oscilloscope would interpret the voltage as a single up-and-down wave with a higher peak and a lower valley. Center-tapped transformers do not necessarily create another phase of power; they merely turn neutral into a reference. If we were to measure that split-phase power as a single 120v sine wave with an oscilloscope, we would have to use neutral as our reference. To measure the separate sine waves for a total of 240v, we would need three probes: a reference at neutral and one reference on each side. Many European countries only use a single sine wave; center-tapped transformers are not commonplace in those countries, and neither is split-phase power. However, the split-phase power in the USA allows for more versatility; we can supply power to 120v appliances where we would otherwise need to use 240v ones. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Bryan describes the tricky concept of power factor and why we should care about it. He also compares power factor to a beer mug to make the topic easier to understand. Power is often represented on a sine wave, which is a curvy line that marks the state of electrical energy at different points on a circle. Power gets stronger and weaker, and it goes above and below the neutral line depending on the excess or deficit of electrons. Unity power factor refers to a power factor of 1, indicating that voltage and amperage are perfectly balanced; there is no lag. However, an inductance (a form of resistance) opposes the current and causes an imbalance between current and voltage. Power loss or quality refers to the difference between the input and output power that results. Apparent power refers to volt-amps, which we'd traditionally consider to be the wattage; however, in an inductive load, the true or real power (wattage) accounts for that power loss and comes from volts x amps x power factor. We can imagine power factor as a mug of beer: apparent power (VA) is the entire mug, the foam is reactive power (wasted), and the beer itself is real power. The power company only charges for the real power, not the reactive power. However, a power factor closer to unity can help prevent motor windings or wires from overheating. To get closer to unity power factor, we need to make sure we have a run capacitor of the correct size. You can measure power factor with a power quality meter. Bryan also covers: Voltage and current Root mean square Inductive reactance Capacitance and how capacitors work Transformer VA ratings If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Bryan lays down some motor speed facts in about 10 minutes in this short podcast episode. We can figure out how quickly a single-phase motor (PSC) will run if we understand how many cycles it will make per second. In the USA, the standard hertz is 60 Hz (60 rotations or magnetic alternations per second). Motors are inductive loads that create an electromagnetic field with a spinning rotor and stationary stator; the amount of poles on the stator determines how quickly the rotor spins (RPM). In the RPM counts, there are some allowances for slip. Slip varies depending on the load, with excessive loads causing more slip. Some multi-tap blowers have additional winding resistance and decreased current (due to the extra taps), which increase the slip. The rated load RPM usually accounts for the RPM at high speed, not medium or low speed with added resistance. On the other hand, variable-speed motors or ECMs are powered by a variable frequency (sometimes a variable frequency drive or VFD). The motor control takes the incoming electrical frequency and converts it into a new frequency (turning AC power to DC and controlling the cycle rate). These motors also tend to be more efficient as a result. The RPM is more variable on these motors with VFDs, whereas we could only manipulate the RPM of single-phase motors by changing the number of poles. When replacing a motor, you can't use a replacement motor with a higher rated RPM than the original motor. The only way to change the RPM is to get a new motor with a different number of poles, increase slip to make it slower or decrease slip to bring it closer to synchronous speed, or adjust the frequency. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Neil Comparetto and John Semmelhack of the Comfort Squad join Bryan to discuss high-quality value design in a high-performance home. They explain how they design HVAC systems (heat pumps) for low-load homes in ways that are affordable, efficient, and comfortable. High-performance, low-load homes need to be energy-efficient AND comfortable, and it can be a challenge to get both. Manual J calculations aren't as common as they probably should be, and it can be difficult to get accurate data about air leakage, power consumption, and radiant gains as well. So, John and Neil try to collect their own data and do aggressive load calculations to avoid the fudge factors that are all too common. The air velocity inside the ducts tends to be lower in these sorts of systems. When you have relatively low airflow in the ductwork of high-performance homes, you don't need as many ducts or for the ductwork to be particularly large. With minimalistic ductwork, supply register placement, face velocity, and throw become very important, especially because those factors are responsible for air mixing. When the duct design conditions are right and the load has been matched, you typically get long runtimes and good air mixing. In many cases, John and Neil use variable-speed motors in their outdoor units that allow for high heating performance. The capacity ranges are wide, allowing the units to run even during exceptionally low-load conditions. They also use flex ducts due to their pre-insulation, noise suppression, and inexpensiveness; they just try to keep it sealed and avoid compressing the ductwork. Neil, John, and Bryan also discuss: Monitoring load conditions with software Design considerations for filter grilles and central returns Room pressurization and airflow testing Transfer grilles The Coanda effect and curved-blade registers Vent sizing Flex duct installation best practices Duct fittings ERVs If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Lacey Dietz with METUS and Scott Arnold with Rycor HVAC join the podcast to talk about how the industry can start putting contractor success first. They talk about Mitsubishi Electric (METUS)'s commitment to contractor success and what that looks like. METUS's contractor program aims to provide training, support, and recognition to create a community of successful contractors. Support comes in the form of marketing, training, tech support, and customer service, and those services are available to contractors who sell and represent Mitsubishi's products. As a contractor who works with Mitsubishi, Scott has been able to specialize the labor in his business and grow his business as one that specializes in installing Mitsubishi systems. Mitsubishi also provided top-quality training and allowed Scott to streamline his training process and get his apprentices feeling confident and ready to go into the field quickly. Adoption rates for Mitsubishi's ductless technology have increased over the past couple of years, especially as people have spent more time in their homes and started re-thinking indoor comfort. Those who are educated about heat pumps also tend to appreciate the technology as well as the mini-split units' small footprints in their homes. The mini-split units' smaller environmental impact than unitary systems is also a plus. Lacey, Scott, and Bryan also discuss: Scott's work with heat pumps in New York Programs that benefit contractors Mitsubishi's products and supply chain management Diamond Contractor program and tiered contractors Mitsubishi's lead generation program and referrals Ductless vs. unitary systems Bringing education into sales Dealing with business growth in a challenging labor market Overcoming objections Learn more about Mitsubishi and its products, visit https://www.mitsubishicomfort.com/, and you can learn how to become a contractor at https://discover.mitsubishicomfort.com/contractors. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Sam Myers with Retrotec talks to Bryan about pressures in the home and why they matter for HVAC solutions at IBS 2022. Technicians focus a lot on ductwork and airflow, but many of them don't focus on how the building envelope impacts HVAC performance. A lot of the HVAC equipment's performance is affected by the push and pull of air caused by leaky areas in the building envelope. If you have a room with too much air and another room with too little, you will have unbalanced pressures. Unbalanced pressures may result in discomfort and latent load issues, especially when unconditioned air is pulled in through the attic. Sealing the envelope well and using dampers as necessary can minimize the comfort issues caused by pressure imbalances in the home. Instead of just using manometers for static and gas pressure, we can also use high-resolution manometers under doors to pick up pressure differences. However, the manometer MUST be high-res to pick up those subtle (but palpable) differences in pressure. A blower door is also a great tool, especially when you use it with a thermal imaging camera; the blower door amplifies the temperature effects that a thermal camera will detect, especially if you also have a good delta T. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

This podcast is a class that Bryan taught for BTrained in Birmingham, AL. He covers troubleshooting, installation, and commissioning best practices with a focus on the fundamentals. To be a good troubleshooter, you must be able to find the problem, identify the source of the problem, fix the problem, and optimize performance based on your data, the customer's comments, and your observations. The Five Pillars of diagnosis aren't comprehensive diagnostic or charging criteria, but they can help you charge or diagnose a system. Isolation diagnosis works best for electrical components; you isolate the problem area from the system and see how the system works without the suspected issue. If the system operates normally without the component in question, then we can conclude that our hypothesis about the "problem" part was correct. Wide-narrow-wide troubleshooting is an approach that allows you to inspect the entire system, zero in on the problem, and optimize the entire system. By starting wide, going narrow, and going wide again, you can troubleshoot holistically. Installations take place in several phases: pre-planning, planning, demo, installation, and commissioning. Many people place a lot of emphasis on the demo and installation and neglect the conversations and procedures associated with pre-planning, planning, and commissioning. Bryan also covers: Heuristics and mental shortcuts Evaporation vs. boiling Rules of thumb Head pressure, suction pressure, and compression ratio Energy transfer fundamentals What superheat and subcooling really indicate Restrictions and temperature drop Delta T "Redneck" compressor test Testing circuits Useful measurements and test instrumentation Causes of compressor failure Measuring airflow Low vs. high static pressure Bringing tribal knowledge to building design Ductless systems, ventilating dehumidification, and sensible heat ratio Manual J, attics, and combustion air Radiant barriers and heat transfer Supply relative humidity Dehumidifier configuration and system design Bad envelopes Vented attics Duct upgrades Total effective length and turning vanes Evacuation Learn more about BTrained at https://btrained.net/ or on the BTrained YouTube channel at https://www.youtube.com/channel/UCnlDsWHT68gVwPrYYO5vhrw. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

Bryan has a bit of an industry nerd out with Ross Trethewey from "This Old House" and TE2 Engineering at IBS 2022 (the International Builders' Show). Ross's education and career have focused on mechanical engineering, especially with sustainable solutions. In building science, the key mindset is to think of the building as a system. Using that school of thought, Ross has developed building science and HVAC solutions that also consider indoor air quality and ventilation, such as hybrid VRF systems. Many of Ross's solutions take the best aspects of air-source and ground-source heat pumps and apply those to hydronics. Some exciting applications for those types of systems could include simultaneous heating and cooling as well as the integration of domestic hot water. Demand control ventilation has been used for a long time in the commercial world, but its possible use in residential applications is another exciting thing to consider. With proper control devices, DCV would give us the opportunity to control temperature, humidity, VOCs, carbon monoxide, carbon dioxide, and radon. In residential applications, DCV has to be a delicate balancing act, as bringing in too much outdoor air would require us to condition that air. High latent loads also present challenges to some of the ventilation solutions in development. Serviceability is another challenge to DCV usage in residential applications; whenever an innovative system is brought to the market, very few people will know how to fix and maintain those systems. One of the possible solutions is to create instruction manuals and give education similar to what already exists for package units. 3D models and animations also help make complicated systems easier to understand. Ross's presence on "This Old House" marks the third generation of Tretheweys on the show. Ross is excited to talk about building science and HVAC innovations and concepts while on the show. Heat pumps are also getting better, especially due to inverter-driven compressors, enhanced vapor injection, advanced control systems, and ECMs. Heat pumps are safer than gas-fired equipment, and we have made them work well in subzero temperatures (because we're nowhere near absolute zero). If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.

In this podcast, Bryan goes through the entire process of replacing a compressor step-by-step. This process is what the Kalos team uses to replace a failed compressor and make sure it doesn't fail again. Before replacing a compressor, you must figure out how the compressor failed; grounded conditions often lead to acid, so it's a good idea to test for acid and see if you need to address a burnout. In any case, make sure you have the correct tools for the job (including a compatible replacement compressor). When you arrive at the job site, be sure to confirm the diagnosis and check to see if the unit has a hard start kit. That's also the time to do a visual inspection, checking airflow as well as the filter, blower, and coil cleanliness. Recover and weigh out the refrigerant charge. Unscrew the foot bolts and lift the old compressor out. Then, seal the compressor once it's out. If you're dealing with burnout, clean out or replace the accumulator (you will install/reinstall it shortly). Cut out and replace the existing liquid line drier and install a suction drier in a place where it can be easily removed. When piping in the new compressor, make sure you protect heat-sensitive parts and do a quality brazing job. Install the new capacitor and hard start kit, too, keeping wiring away from places where it may chafe. Test for leaks, evacuate the system, charge the system, and check your five pillars as well as voltage. Finish by cleaning the drain and double-checking airflow. Bryan also covers: Misdiagnosed compressor failure Parts needed for replacing a compressor What makes a compatible replacement compressor? Billing and pricing Alloys and fluxes Replacing TXVs, capacitors, contactors, and reversing valves Cutting vs. unsweating Suction driers and pressure drop Charging considerations If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.