Bryan Orr and Steve Rogers dive deep into measuring power consumption in HVAC blower motors, particularly focusing on the differences between PSC (Permanent Split Capacitor) and ECM (Electronically Commutated Motor) technologies. The discussion stems from a question raised at an educators' conference about the accuracy of clamp-on meters in measuring blower motor watt draw, as specified in the ACCA Standard 310. Steve shares insights from extensive testing conducted with different types of motors and power meters. The tests compared PSC motors with constant torque and constant airflow ECM motors across various static pressure conditions. One key finding was that two out of three field-available clamp-on meters tested were capable of accurately measuring true power at levels expected in residential blower motors. However, one meter showed significant inaccuracy at low power levels, highlighting the importance of carefully reviewing meter specifications before use. The conversation delves into the concept of power factor and its crucial role in understanding the true power consumption of ECM motors. Steve explains that ECM motors often have a low power factor (around 0.6), which can lead to misconceptions about their efficiency if only the current draw is measured. The discussion emphasizes the need for proper measurement techniques, including simultaneous voltage and current readings with the blower door on, to accurately assess motor efficiency. Key topics covered in the podcast: Differences between PSC and ECM motor technologies Importance of power factor in measuring true power consumption Accuracy of field-available clamp-on meters for power measurement Impact of static pressure on motor performance and efficiency Misconceptions about ECM motor efficiency and longevity Proper measurement techniques for assessing blower motor watt draw Relationship between duct system design and motor efficiency Implications of ACCA Standard 310 for HVAC installations Challenges in comparing constant torque and constant airflow ECM motors The role of control algorithms in ECM motor performance Importance of understanding meter specifications for accurate measurements   Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

In this short Q&A podcast, Bryan answers a listener-submitted question about sizing heat pumps for heat load in heating mode, something that we haven't talked much about in the past due to the greater need for cooling in our market. In most cases across the country, a heat pump's heating loads will be greater than the cooling loads. There is a greater swing between the desired temperature and the actual temperature in heating mode than in cooling mode (in terms of sensible BTUs). We don't want to oversize for cooling because of its lower efficiency, comfort, and humidity control due to the shorter runtimes. (However, oversizing for cooling loads is far less of an issue in arid climates.) We don't want to oversize the heat pump to meet the heating load when we'll far exceed the cooling load. However, that's not much of a concern for the opposite scenario in which we oversize for heating to meet the cooling load. We can add auxiliary heat, such as electrical heat or natural gas in dual fuel setups, to help us meet the heating load; we don't have those same options in cooling. Variable-capacity systems can also be beneficial in scenarios where heating and cooling loads are massively different. Bryan is excited about future opportunities for standby cooling and heating capacity, such as in the case of a heat pump heat recovery chiller system with buffer tanks. In the meantime, we have to design for vastly different heating and cooling loads and may have to oversize for one or the other.   Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

This episode of the HVAC School podcast dives deep into the often-overlooked but critical topic of water issues in HVAC systems. Bryan and Bert discuss the various causes of water leaks and condensation problems, and they explain how to prevent them. They emphasize that water damage is not an inevitable part of HVAC systems and that with proper attention to detail and understanding of the underlying causes, most issues can be prevented. "Spidey Sense" refers to a heightened situational awareness that allows technicians to anticipate and prevent water-related problems. Common water-related problems include drain backups, improper trap depth, and freezing issues, and Bryan and Bert provide practical advice on how to identify and address these problems. The conversation also covers the importance of proper installation techniques, including the correct placement of float switches, insulation of copper lines, and the pitching of secondary drain pans. Bryan and Bert highlight the need for technicians to think critically about the root causes of water issues rather than relying on quick fixes or common misconceptions. They debunk myths such as thermostats being set too low and causing freezing, and they emphasize the importance of addressing underlying airflow problems. They also discuss the challenges of condensation in humid climates and the importance of setting proper customer expectations. Key topics covered in the podcast include: Common causes of water leaks in HVAC systems The importance of proper drain installation and maintenance Freezing issues and their real causes Secondary drain pan installation and common mistakes The role of static pressure in drainage problems Condensation issues on outdoor units and in humid climates The importance of proper insulation for copper lines and drains Best practices for installing and connecting float switches Debunking myths about thermostat settings causing freezing The need for critical thinking and thorough investigation of water issues   Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

In this short Q&A podcast episode, Bryan answers a listener-submitted question about cultural diversity in the workplace, especially at an HVAC company. He addresses how we can deal with cultural and language differences in a field where communication is so important. Being open to different demographics of people is great for the industry, especially since we have an aging workforce and need good people in the trade. There are also plenty of opportunities in the trade. However, that doesn't automatically erase the challenges associated with hiring people who don't speak English fluently with English-speaking clients, especially when it comes to money conversations. (However, you can also increase your client base by being able to serve people who speak other languages.) Our operations can aid these people and help them integrate into the workplace by offering ESL classes as a workplace benefit, encouraging everyone to be clear and concise in their communication, embracing other forms of communication (like sharing photos), and offering scripts or guidelines for communicating with customers. Cultures vary, and we can't afford to take a mindlessly xenophobic or excessively open approach. We need to acknowledge what's good for the business and uphold standards, but we need to make space for people of different backgrounds to succeed and contribute to the company and industry. It's also great to get to know people who aren't like us and show interest in other cultures, especially when we get to know them and their families.   Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

In this informative episode of the HVAC School podcast, host Bryan Orr sits down with Tom Lorenz to talk about some of the Sensi thermostat features, particularly aux lockout and balance point. Tom leads the traditional and smart thermostat lines at Copeland and has over 25 years of experience in the industry. The discussion focuses on two key features of heat pump thermostats: auxiliary lockout and balance point. Tom explains that auxiliary lockout is crucial for energy efficiency, as auxiliary heat (whether electric or propane) is typically more expensive than heat pump operation. All Sensi thermostats now include this feature, which can use internet weather data or a physical outdoor sensor to determine when to engage auxiliary heat. Balance point settings are complex, and there's no one-size-fits-all approach. Factors like heat pump efficiency, home insulation, local climate, and energy costs all play a role in determining the ideal balance point. They emphasize the importance of contractors understanding the specific equipment and secondary heat source when setting up a system for optimal performance and efficiency. The conversation also touches on Sensi's approach to thermostat design, prioritizing ease of use and essential features over feature bloat. Tom highlights Sensi's commitment to user testing and creating intuitive interfaces for both contractors and homeowners. The podcast concludes with resources for listeners to learn more about Sensi thermostats and advanced HVAC control strategies. Key topics covered: Auxiliary lockout feature in heat pump thermostats Balance point settings and factors affecting them The importance of understanding equipment specifications for proper setup Sensi's design philosophy focusing on user experience Different methods for determining balance point (logic-based, internet weather, outdoor sensor) Energy Star certification requirements for thermostats The evolution of thermostat technology from mercury bulbs to smart controls The Sensi app and its features, including remote sensor integration The importance of contractor education in proper thermostat setup Resources for learning more about Sensi thermostats and advanced HVAC controls   Visit Sensi's site at https://sensi.copeland.com/en-us, and learn more about Sensi's contractor branding at https://hvacrschool.com/sensi.  Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

In this short Q&A podcast episode, Bryan answers Howard's question about how to deploy a dehumidifier (dehum) in a sealed home. He addresses things like location and fresh air requirements in green-grass markets with high dew points.  Before deploying a dehumidifier, you will need to know about the climate, the structure, and the client's complaints, budget, and comfort goals. You need to make sure the HVAC system is properly installed; the most common obstacle to proper dehumidification is oversizing. HVAC systems need a cold coil to pull moisture out of the air, and we need adequate (but not too much) ventilation in the structure before deploying a dehumidifier. Common obstacles include leaky structures, venting exhaust air into the attic, and constantly running exhaust ventilation (like range hoods or bath fans). Bryan's preferred setup is to have a dedicated dehumidifier just for the sealed attic, though you can make the HVAC do this if you plan it out during the construction phase. If you bring in outdoor air, you should plan to bring it in through the dehumidifier, but that can interfere with attic dehumidification. You can either use two dehumidifiers or use powered dampers to dehumidify either the attic or house at different times. You can consult the expertise of groups like the HVAC Grapevine and manufacturers like Santa Fe Dehumidifiers. HVAC School also has a range of dehumidifier topics; you can search for videos, podcasts, and tech tips on the topic in the app.   Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

In this episode of the Spidey Sense series, Bryan and Bert dive deep into the art of refrigerant leak detection, sharing their wealth of experience and practical tips for HVAC technicians. They emphasize the importance of using one's senses and observation skills before relying solely on electronic tools, highlighting how this "Spidey Sense" approach is a hallmark of senior-level expertise in the field. Visual and tactile cues, including warm suction lines, frosted components, and signs of oil, are vital. Different symptoms point to specific kinds of leaks and various scenarios, so you need to understand the behavior of the system.  Bryan and Bert also discuss the strategic application of soap bubbles, electronic leak detectors, and nitrogen for pressurization. Each method has limitations, and you'll need to know when to employ them for maximum effectiveness. When detecting leaks, consider recent home renovations or equipment vibrations that might contribute to leaks. Topics covered in the podcast include: Visual and tactile cues for identifying potential refrigerant leaks The debate on frosted lines as indicators of low refrigerant charge Proper use of electronic leak detectors and their limitations Strategic application of soap bubbles in leak detection The importance of checking common leak locations (e.g., flare fittings, evaporator coils) Considerations for leak detection in newly installed or recently serviced systems The role of nitrogen in leak detection for systems with very low refrigerant charge Estimating the severity of a leak based on system pressure and charge level The pros and cons of isolation tests for line set leaks Techniques for detecting very small, slow leaks that might not show up in pressure tests The potential use of ultrasonic leak detection tools The importance of thorough inspection and patience in the leak detection process   Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

In this short Q&A podcast episode, Bryan answers Edward's question about how to deal with customers who ask, "Why didn't you notice it last time?" There isn't an easy answer to that question. The truth is that air conditioning and home health and comfort issues are complicated, and it's entirely possible that an issue simply went unnoticed (or the symptoms simply weren't apparent yet). The HVAC industry doesn't have a standard slate of tests that can give a comprehensive view of everything that's wrong with a system all at once. It's similar to how a doctor can offer a second opinion that differs from the first doctor you saw.  You have to determine whether the customer wants to place blame or solve the problem when they ask, "Why didn't you notice it last time?" Sometimes, we need to dig deeper to find the root of the problem. We can offer advanced diagnostics and be honest about what that will entail (including pricing), though it's natural for customers to be apprehensive about being sold options. However, we don't want to avoid pursuing solutions either. There are ways to talk about previous sloppy or incomplete work without placing blame on another technician. The immediate problem is what requires attention, not the last person who worked on the system. Ask the customer to state their goals and the results they want to see, and you can forge a path ahead.   Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

In this episode of the HVAC School podcast, host Bryan dives deep into the topic of vacuum in HVAC and refrigeration systems. He addresses two questions from social media about vacuum, expanding them into a comprehensive discussion of best practices, common issues, and techniques for effective vacuum procedures. Bryan starts by explaining where to ideally locate a vacuum pump when working on a refrigeration system. He emphasizes the importance of pulling from the largest volume locations possible, often at multi-position service valves on the compressor or wherever accessible ports are available. He notes that systems that have been in operation pose unique challenges due to refrigerant dissolved in the oil, which can significantly increase vacuum time. The podcast then covers the "one hose method" for pulling vacuum, detailing the process of using a single large hose connected to the suction side with the core removed, while placing the micron gauge on the liquid side. Bryan explains how this method can be highly effective for new systems but may take longer for systems that have been in operation. He also discusses the importance of valve quality. Key topics covered in the podcast include: Ideal vacuum pump location in refrigeration systems The "one hose method" for pulling vacuum Challenges of vacuuming systems that have been in operation Using heat and nitrogen to improve vacuum efficiency Importance of quality valves and tools in vacuum procedures Proper maintenance of vacuum pumps and micron gauges Dealing with refrigerant dissolved in oil during vacuum The science behind evaporation at the oil-vapor interface Tips for speeding up vacuum in difficult conditions Recommended resources for further learning about vacuum techniques   Get your copy of Review of Vacuum for Service Engineers at TruTech Tools HERE.  Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

In this short Q&A podcast episode, Bryan answers a question about drain traps and static pressure. This question was sent by Stephen with The Comfort Squad when he noticed an uptick in nuisance calls on retrofit systems that kept having their secondary drain pans filled. In negatively pressurized systems (i.e., straight-cool or heat pump units, not gas furnaces), air can pull water back into the drain line. The evaporator coil is under negative pressure because the blower is on top of the evaporator coil. The rule of thumb for trap depth is that it should be greater than or equal to twice the return static pressure (which is why a 1" deep trap is typical for systems with 0.5" return static pressure). However, return static can have some variation, and it's also not a great idea to use the TESP for this measurement because the return static could be greater than the supply. It makes most sense to account for the highest possible return static you will see. 1" is only sufficient if 0.5" return static pressure is the most you will see, so bigger is usually better in all cases. If you can install a 2" or 3" trap, you'll typically have your bases covered without having an excessive trap.    We also wrote a tech tip about this topic: https://hvacrschool.com/drain-trap-depth-and-negative-pressure/  Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at https://hvacrschool.com/symposium. Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.