HVAC School - For Techs, By Techs

David Holt with the National Comfort Institute (NCI) returns to the podcast to talk about high-performance HVAC and what the heck it even is.  High-performance HVAC is all about delivering the highest possible equipment performance out of the box. High-performance HVAC is a key element of NCI's work; equipment should be able to deliver the health, comfort, safety, reliability, and efficiency expected by the occupants, and equipment that can't do that often has root issues we need to troubleshoot and fix. In many cases, the root cause has something to do with airflow issues. As contractors, we can focus more heavily on testing fan airflow to get to the bottom of poor HVAC performance, even when there may not be an apparent airflow problem. We need the proper test instrumentation to measure CFM, a key indicator of performance. We can't expect to maximize system performance until the airflow is correct across the heat exchange surfaces. Many factors that contribute to poor equipment performance actually have to do with building science, including issues like air leakage. Although HVAC contractors can't control that, we can be successful if we have a culture and mindset that makes us put our customers first and work with the circumstances we're given to deliver the best possible solution. David and Bryan also discuss: David's role at NCI Manufacturer, distributor, contractor, technician, and customer relationships How to measure CFM effectively Effects of improperly  Issues that arise during building construction Parts vs. equipment vs. systems What makes a good service technician The high-performance mindset Having a classroom vs. a commitment to training   If you want to get more involved in HVAC training, you can text David at (706)-332-2212 or visit https://nationalcomfortinstitute.com/pro/. Learn more about NCI's High-Performance HVAC Summit at https://www.gotosummit.com/.  Check out the HVACR Training Symposium and order your virtual tickets before, during, or after the symposium (Jan 19-21, 2023) at https://hvacrschool.com/symposium.  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 returns to the podcast to talk about setting realistic customer expectations when designing residential HVAC systems across climates, seasons, and load conditions. Being honest and aggressive is one of the best ways to set realistic expectations, and our load calculations and equipment selection need to reflect that. Manual J calculations must consider non-design days, not just the design conditions, including partial load conditions. Partial load conditions that aren't accounted for may make it more difficult for the HVAC system to control latent heat, potentially leading to moisture problems indoors. We have to set expectations in the summer a bit differently than we set expectations in the winter, and we must account for the equipment type when we create expectations. Heat pumps perform differently than furnaces, and oversized furnaces typically present fewer problems than oversized heat pumps in areas with high latent loads.  Clients must also be willing to acknowledge that systems won't perform exactly as designed during partial load conditions. You can put the information in writing and make clients sign the paperwork to ensure that they understand the expectations you've set. Laying out expectations and making clients read them is a good way to prevent conflict or identify clients that may not accept the expectations. Ed and Bryan also discuss: Ed's three "Hate Me" reasons Oversizing furnaces vs. straight-cool A/C units vs. heat pumps Electrification Heat pumps in cold climates Humid vs. arid climates Designing systems with ancillary dehumidification Not being responsible for clients' lifestyle choices ACCA collaboration and industry support   Learn more about the training ACCA has to offer at https://www.acca.org. Check out the HVACR Training Symposium and order your virtual tickets before, during, or after the symposium (Jan 19-21, 2023) at https://hvacrschool.com/symposium.  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.

Craig Migliaccio, aka AC Service Tech, returns to the podcast to share his knowledge about mini-split install & service. He also talks a bit about his upcoming book, “Inverter Mini-Split Operation and Service Procedures.” Mini-splits are unique because they are compartmentalized in ways that traditional central-air ducted systems are not. Mini-splits come in many varieties, including ducted and ductless types, as well as multi-zone types. Many are inverter-driven and have more electrical efficiency as a result and can vary their capacities based on load variation.  Mini-splits have metering devices at their outdoor units, and these devices may be electric expansion valves (EEVs) or capillary tubes. Inverter mini-splits also don’t have filter driers because their PVE oil doesn’t have the same acid concerns as POE oil, and they don’t have traditional liquid lines. Flare connections are also critical when installing ductless systems, especially because you want systems to be tight to prevent leaking and contamination. Craig likes eccentric flaring tools with offset cones, and he recommends using flare nuts from the equipment manufacturer, not the line set manufacturer. He covers other flaring best practices as well. The charge is quite small in mini-splits, so weighing the charge and being careful and deliberate during charging is critical. Refrigerant leaks can also be highly problematic; corrosion and poor flare connections are common causes of leaks.  Craig and Bryan also discuss: Hyper-heat systems Coefficient of performance (COP) and BTU output Moving between PSC and ECM or inverter technologies Mini-splits vs. VRF/VRV technologies Pressure testing and leak detection Compressor diagnosis  Thermistors and electrical resistance Heat sinks and mounting circuit boards Selecting a location to install a mini-split Things to consider when checking the charge Why measure superheat and subcooling? Cleaning and maintenance best practices   Check out Craig’s YouTube channel at https://www.youtube.com/@acservicetech.  Starting January 1st, 2023, you can buy Craig’s book on his website, which has a bunch of other good resources. Visit that site at https://www.acservicetech.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.

David Richardson from NCI returns to the podcast to talk about why CO (carbon monoxide) doesn't leak and what it does instead. CO is a highly dangerous gas that is colorless and odorless, and we can keep ourselves safe by staying aware of it with personal low-level CO monitors. However, CO doesn't leak; it spills, especially via backdrafting, a blocked flue, or updrafting. Whenever the flue gas comes back inside the structure unintentionally, there is room for a potential CO problem. With proper testing, we can determine the cause of that spillage and make the best choice to stop it from happening. When there is an excessive draft, there's often turbulence in the draft hoods, which leads to spillage. Spillage commonly happens at the draft hood, but it can also happen near the burner compartment of a gas appliance. Smoke tests won't detect that, but CO testing will. However, we need to look for rising CO levels over the run cycle of the equipment. If you test CO levels in the ducts, you're only seeing how the fans are distributing the CO; you're not checking the likely source of CO. Water heaters often give visual clues of improper venting, especially if there's soot, rust near the venting, or discoloration near the burner compartment. David and Bryan also cover: CO poisoning symptoms CO monitors vs. alarms The roles of stack effect and airflow in CO spillage Air taking the path of least resistance CO testing best practices CO and changes in sinus pressure Combustible gas leak detectors Low-level CO monitors Wind and its effects on pressurization or depressurization Electric appliances, generators, and CO poisoning   Learn more about NCI's training courses at http://nationalcomfortinstitute.com/. You can also contact David directly at davidr@ncihvac.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.

Jim Fultz with Emerson White-Rodgers returns to the podcast to talk about one HSI furnace control to rule them all, the 50M56X-843 Universal Single Stage Integrated Furnace Control. The 50M56X does not come with wiring harnesses; the control comes with the plugs that the majority of manufacturers use, making it a versatile and user-friendly universal part. It also works with the White-Rodgers Connect app to help you configure the part with the burners. You can also do some basic configuration when it comes to the blower motor. With the 50M56X and Emerson White-Rodgers Connect app combination, you can quickly and accurately configure the control without wi-fi or a password.  An igniter is included in the box with the 50M56X; the igniter must match the control. The control also comes with a three-digit display that communicates the microamp current from the flame sensor, meaning you don’t need to use a meter on the flame sensor. So, you can carry less truck stock and complete more calls with this universal part. The device also has some potentially useful extra features. For example, the 50M56X stores error codes for 14 days, not permanently, to prevent causing confusion for future technicians. It also has a bus connector for the thermostat and a dehumidification terminal for thermostats with dehumidification capabilities. Jim and Bryan also cover: White-Rodgers universal vs. aftermarket vs. OEM parts Blower speed and X13, ECM, and PSC motors Near-field communication (NFC) capabilities  Cross-referencing Technology and ethical business 50M56X warranty information Integration with Sensi thermostats WR Mobile App (available on Google Play and the App Store)   Learn about Emerson White-Rodgers and their featured products on our partner page HERE. Check out the wide array of products and resources Emerson White-Rodgers has to offer at https://emerson.com/universalcontrols. 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.

Yaron Ben Nun from Nostromo Energy joins the podcast to talk about ice banking, a way of using ice to balance energy consumption. Nostromo Energy is an Israel-based company that has recently started working in California. Water has a very high latent heat of fusion, meaning it can absorb and store a lot of energy between its solid and liquid states of matter. By storing ice, Nostromo Energy can support commercial and industrial structures that utilize chiller-type applications by offering a clean and sustainable battery thanks to water and its physical properties. Load balancing or management will be critical as the electrification of heating sources continues. Lithium-ion batteries aren't sustainable solutions in many of these cases, and that's where ice banking can support the grid by providing a thermal battery. Water offers many advantages as a medium for storing energy, especially since it is natural and doesn't have the numerous economic and labor concerns that come with the production of many other batteries. However, there have been some challenges with the widespread adoption of ice banking, especially when it comes to retrofitting and the ability to match the demand for new power stations. Water is also heavy, meaning that it can be difficult to manage in rooftop applications. Nostromo Energy keeps working to solve those problems and increase the coefficient of performance (COP), especially by maintaining a relatively high freezing temperature.  Yaron and Bryan also discuss:  Yaron's career and Nostromo Energy HVAC equipment and the electrical grid Economic and labor factors of lithium-ion battery production Discharge rates and glycol cycles COP and compression ratio Heat recovery chiller technology Carbon counting, kilowatt-hours, and carbon emission Thermal energy storage and tax rebate eligibility   Learn more at nostromo.energy. 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 why we need to pay technicians and field workers better in the HVAC industry and how small and medium businesses can help current employees. When the pay for entry-level HVAC positions can't compete with fast-food, retail, or warehousing jobs, we can't expect people to flock to the industry, especially since so much skill is required. Overtime is also almost unavoidable in many places, and it's a problem that requires a more nuanced solution than getting more trucks on the road. The tricky part about paying more for overtime is that it's challenging to implement pricing structures that charge the end user proportionally. As prices for equipment, fuel, and living essentials go up, the company often has to eat those extra costs if they want to pay their technicians fairly. In some cases, HVAC businesses feel bad for the customer when the cost of everything increases, which could be doing a disservice to the techs who deserve higher wages for their work. HVAC companies can increase their value by setting themselves apart in their markets, such as by performing unique services that benefit customers; effort and skill are required, which can justify higher prices. We have to be realistic about what our competitors are selling and work towards selling comfort, not just parts or systems. Eric, Ty, and Bryan also discuss: Challenges with reducing overtime HVAC sales and higher pay rates Customers' willingness to pay Base pay and incentives How managers can take care of their employees Understanding employee motivation Using profits for personal luxury items vs. reinvesting in a business Knowing our numbers Understanding employee discussions about pay   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.

Dr. Chuck Allgood from Chemours returns to the podcast to do some refrigerant myth-busting. Many people don’t understand why high-GWP HFCs can impact the atmosphere if the refrigerant is heavier than air. High-GWP HFCs exist for a long time, and they last long enough for natural mixing and the wind to distribute their molecules throughout the atmosphere. HFOs, by comparison, are more reactive in the atmosphere and have relatively short lifespans, meaning they have less of an effect on the environment. Even though refrigerants with lower GWPs are entering the market, it’s always been our job to keep refrigerants inside the system where they can’t harm the environment. However, when leaks occur, these lower-GWP refrigerants break down quickly outside the system but not inside it. Contractors and manufacturers should still work together to reduce leak rates as much as possible, even as we keep innovating. Another common myth is around “natural refrigerants,” which are common in some forms of refrigeration, but “natural refrigerants” may be a misleading term; although you find them in nature, they undergo heavy manufacturing and processing before being used in HVAC/R systems. Even “non-toxic” and “non-flammable” labels for A1 refrigerants may be misleading, as they don’t capture the full picture of their risks. There are also some myths around oil miscibility; oil still needs the help of refrigerant velocity and volume to move it through a system. POE and PVE oil are great in terms of miscibility and also get entrained in the refrigerant to ensure good oil return to the compressor. Dr. Chuck and Bryan also discuss: Dr. Chuck’s recent work and research “Heat rises” and buoyancy Pseudoscience HFO stability and reactivity Trifluoroacetate (TFA), toxicity, “forever chemicals” Education and change in the industry “Future-proof” vs. innovation Phosgene   Learn more about Chemours and their A2L training at opteon.com. You can also check out the Chemours/Opteon YouTube channel at https://www.youtube.com/@OpteonProducts/videos.  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.

Ty Branaman and Eric Kaiser return to the podcast to discuss the good, the bad, and the ugly of trade schools. They cover the opportunities and challenges they've observed in trade schools. As with for-profit colleges, for-profit trade schools market programs aggressively and can take people who are at a crossroads in their life and saddle them with debt. In some cases, trade schools are hesitant to fail people and end up passing people who don't have the technical proficiency to be effective tradespeople. Sometimes, trade schools don't emphasize practical skills and contractors' experiences as much as they could, either.    The tricky part about trade schools is their allocation of resources, which instructors typically can't control. Sometimes, too much money is spent on equipment, and not enough is spent on the instructors. There needs to be an appropriate balance of both in an effective program. Administrative distractions can also make programs less likely to produce effective technicians. The admission process also doesn't always sort people into appropriate classes; many people with low proficiency are put into classes that are too advanced for them. People are going into trade schools with less mechanical aptitude than in previous generations, and trade schools often skip over the basics of tool use. Students need to know how to use tools before they learn how to fix systems, and that tool proficiency needs to be reinforced. Continuing education is also more focused on paperwork than application and isn't as thorough as it probably could be. Ty, Eric, and Bryan also discuss: First-generation trade school graduates Administrative challenges with trades instructors Motivating students Instructor qualifications "PowerPoint teaching" Automated systems Bringing work experience to the classroom Where does podcasting fit into trades education?   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.

John Pastorello from Refrigeration Technologies returns to the podcast to talk about selecting proper cleaners for various HVAC/R jobs. From the beginning, the goal of Refrigeration Technologies has been to make cleaners that are safe but have the same effectiveness as the strong, hazardous varieties in the industry. The more hazardous cleaners are not food safe and may be corrosive, dangerous to inhale, or irritating to the skin or eyes. Some cleaners can also damage components; brighteners aren’t recommended for use on aluminum coils for that reason.  John is a fan of foaming cleaners because the foam gives the cleaner more contact area and holds the detergent in place for a longer time. Foaming cleaners tend to be good for degreasing. However, if used improperly, the foam can overflow in the drain pan and get messy. Many residential and light commercial HVAC contractors may benefit from keeping Viper EVAP+ for evaporator coils, Heavy Duty for condenser coils, and Brite only when there is an extremely dirty condenser coil. The Viper aerosol coil cleaner can also work well for small systems. The Pan & Drain Treatment also keeps drain sludge and odors at bay inside condensate lines and pans.  Instead of relying on harsh chemicals to dissolve microbial growth, Refrigeration Technologies cleaners help use enzymes to dissolve odor-causing biological material in HVAC systems. John and Bryan also discuss: PPE to use when working with cleaners Acid-based cleaners and “non-acid” cleaners Dwell time and contact Dilution ratios NSF registration and what it means to be “food-safe” Viper Venom Packs   Watch our 3D video showing how to use several Refrigeration Technologies products HERE. Learn more about Refrigeration Technologies products and resources at refrigtech.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.