

HVAC School - For Techs, By Techs
Bryan Orr
Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.
Episodes
Mentioned books

Aug 13, 2020 • 1h 27min
Troubleshooting & Commissioning Q&A
In this podcast episode, Kaleb, Joe, Eric, and Bryan answer some troubleshooting and commissioning questions from Facebook. Whether we're talking about troubleshooting, commissioning, or any other HVAC/R task, the best training is on-the-job training. Meetings, educational videos, and quizzes also help to a lesser extent, but bypassing training altogether is a mistake. Senior techs can also become better diagnosticians when they teach others. "The Diagnostic Game" is an especially useful tool to help teach newbies how to troubleshoot a system. However, training is something that is ultimately what you make of it. When you consider external training, you must consider the value of that training. (For example, NOVAR training would be useless for a residential tech but critical for a grocery refrigeration tech.) You also want to make sure your training makes you a valuable job candidate and that you stay motivated throughout training. When it comes to diagnosis, you can't truly diagnose the equipment until you know how it operates under normal conditions. Until you become familiar with normal equipment operation, you're essentially relying on trial-and-error. Getting the answer correct is only part of the equation; you also need to know why the answer is what it is when troubleshooting. Kaleb, Joe, Eric, and Bryan also discuss: Leaving subcooling just shy of the target value Balancing the charge during a hot pull down How much can we expect techs to do training on their own time? Just-in-time education The relationship between training and pay raises "Understand before you do" Replacing parts on a unit with a failed compressor Megohmmeters and multimeters The Kalos residential commissioning process Troubleshooting no-cool calls Inspecting customers' homes Communicating with customers Money-losers for residential companies Classroom training vs. field experience Fluid dynamics in ductwork Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Aug 6, 2020 • 48min
Advanced Fresh Air w/ CERV2
In this podcast episode, Ty Newell from Build Equinox comes on to discuss the CERV2 and how it embodies "advanced fresh air." The CERV2 is the second-generation version of the CERV. A basic ERV allows for discharge air leaving the home to pass the intake air. When the airstreams cross through a core, there is an exchange of sensible and latent energy. The ERV may promote dehumidification and cooling of the incoming air. The CERV is a form of ERV technology, but it addresses the issues that may arise from crossing the airstreams. For example, we don't always want to exchange energy, so sensors can examine the air content and determine when and when not to exchange energy. The CERV, an advanced fresh air solution, went into development in 2008, and the first unit was built in 2010. The CERV has sensors for carbon dioxide and VOCs; either one of those may dominate the air quality in the home. The CERV also uses a heat pump to exchange energy and help heat or dehumidify fresh air coming in. The CERV also has higher CFM than most ventilation solutions, meaning that it can flush out pollutants effectively. So, the CERV acts as a supplementary heating/cooling source for maximum comfort and indoor air quality. Build Equinox is a small company, and it has about 400 CERV/CERV2 units spread throughout North America. However, because the market is small, they can examine feedback very closely. Ty and Bryan also discuss: Potential downsides of bringing in outside air Dehumidification for CERV Recirculation mode CERV unit controls Using hydrocarbon refrigerants Concerns with microchannel coils Oil carry, miscibility, and foaming Superheat control Assessing indoor air quality Sensitivity to IAQ threats Latent-dominated, sealed residential constructions Testing and choosing sensor technology Check out more at buildequinox.com. Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Jul 30, 2020 • 41min
Combustion Analyzer Facts and Mistakes
Our main man, Bill Spohn, joins us again to talk specifically about combustion. He also explains how to select and properly utilize a combustion analyzer. It's critical to do combustion analysis when you service equipment for the first time or just after installation. We need benchmarks, so that's when our combustion analyzers can come in handy. (Of course, you also want to use your senses to inspect the equipment.) Commissioning is another good time to bust out your combustion analyzer. Combustion analyzers should properly measure oxygen, temperature, and CO. Oxygen and temperature sensors tell you the combustion efficiency, and the CO sensor tells you about the carbon monoxide content. However, the CO sensor should also have a NOx filter to prevent nitric oxides from showing up as CO. The goal is to have no CO present in the living space, and sensors that pick up NOx can raise a false alarm. Some combustion analyzers also have pressure sensors, which can detect static pressure drops across heat exchangers or filters. You can use these for some building-performance tests, including zonal pressure diagnostics. You can also potentially measure ambient CO with your combustion analyzer. Once you have your combustion analyzer, you need to calibrate it and maintain it. Temperature sensors rarely need recalibration, but your CO sensor needs occasional recalibration after repeated exposure to gas. NOx filters can also expire and may need replacement. Overall, combustion analysis is a critical part of gas furnace inspection. However, it's best to use other inspection methods too, such as looking for heat exchanger leaks. Bill and Bryan also discuss: Flame displacement Condensation buildup Nitric oxides on CO sensors Dilution of CO and base signals CO alarms How CO sensors work How air enters the home Induced-draft systems under negative pressure in the flue Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Jul 28, 2020 • 20min
Advice on Starting an HVAC/R Career - Short #98
In this short podcast, Bryan shares some of his advice for people looking to get into the trades by starting an HVAC/R career. When you step into the HVAC/R trade, you must remember that you'll acquire a mix of skills and talents that all work together. You must reflect on yourself and see if you'll be a good fit for the trade. Do you enjoy working with your mind and your hands? Do you enjoy working to some degree? If you don't like pressure or dislike working with your mind or hands, then the HVAC/R trade isn't for you. When starting an HVAC/R career, you don't want to rely on a system or process to provide you with everything you need. Trade schools won't provide the full scope of field education, so you can't rely on them for everything. Instead, join social media groups where professionals discuss equipment and answer questions. Watching reliable YouTube channels helps a lot, too. Self-motivation is the key to success in this career. Don't go into an HVAC/R career if you aren't motivated to jump into new tasks or subjects. The best way you'll learn in the trade is by practicing with your own hands. Brazing and soldering are more advanced skills that your senior techs probably won't let you do on customers' equipment. However, you can read plenty of guides and practice on your own once you feel confident. You can also study for and take EPA tests on your own. There are several points of entry to the trade: apprenticeships, trade schools, and entry-level positions with companies. The one you choose will largely depend on the availability and quality of each in your area. You want to spend a lot of time working with your hands, no matter which path you choose. Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Jul 23, 2020 • 35min
Air Flow Hood Considerations w/ Dwyer
Jaden Lane joins us to discuss some best practices when using an air flow hood. She also explains how the Dwyer Smart is innovating in the hood space. An air flow hood is an excellent tool, but we can't just assume that it'll work correctly in any system. Various vents and diffusers can cause different flow patterns to reach the hood, so you can get an incorrect reading if the flow hood is not aware of the flow pattern. Unless we give the hood background on what's going on in the duct, there's no way the hood will know the correction factor to give you the correct reading for the conditions in the duct. You can adjust smart flow hoods to compensate for inaccuracy factors. Hoods are like big canvas skirts that you place over a vent, and there's a flow grid at the bottom. As air moves through the hood, the grid takes airflow readings. There are pitot arrays that act as traverse points on a duct traverse; these arrays take multiple measurements and give you an average. These devices work better when the air is a bit turbulent. If you doubt your measurement, you can also try the hood in different 90-degree orientations (but keep it centered). Dwyer does a lot more than just make test instruments. They have a rigorous testing process for their products; their products can also work as permanent installations within buildings, not just tools for technicians. Jaden and Bryan also discuss: Dwyer products, including the Magnehelic Vent vs. grille vs. register vs. diffuser Computational fluid dynamic analysis and other test methods Calibration vs. zeroing Predictive balancing Choke and backpressure Vane and hot-wire anemometers Check out Dwyer at dwyer-inst.com. Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Jul 16, 2020 • 42min
3D Duct Modeling For Residential
Russ King joins us to discuss simplifying duct design for residential contractors. We focus on using 3D software for duct modeling. While computers are great tools for duct design, you must be careful with them. Computer technology doesn't correct your mistakes; it allows you to make mistakes more quickly. Russ made 3D software specifically for duct modeling, and its goal is to help technicians/contractors with duct designs and equipment sizing. The software is good for quick duct design, can determine flex duct design, and is ideal for broad usage in residential HVAC. Russ has noticed that existing energy modeling and load calculation software ask for extremely specific inputs, which can confuse technicians. He was frustrated with the process and wanted to make software that could help technicians solve the problems that mattered in a way that made sense. With the help of his son, Russ came up with Kwik Model (of Coded Energy). They developed software that allows users to design ducts and adjust parameters easily. The goal is for Coded Energy to be a simple, straightforward duct design software that addresses the hardest duct design issue: making the ducts fit. Coded Energy is written in Unity, which is used for video games and architecture/automotive design. The user essentially imports a floor plan, scales it, places boxes, and stretches the boxes to meet the design conditions. Once the user has built the house, the software can calculate the surface area automatically. Then, the user can use EnergyGauge for load calculations and equipment selection. The user can then draw ducts and have the software size the ducts for them. Russ and Bryan also discuss: Equipment selection for latent removal capacity Oversizing issues Designing ducts for building plans Comfort diagnostics 2D vs 3D modeling Getting feedback in the field post-design Visit kwikmodel.com to learn more. Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Jul 9, 2020 • 1h 6min
How to Effectively Choose and Use Test Instruments
Bill Spohn with TruTech Tools joins us to talk about why being “approximately correct” is better than being “exactly wrong” when it comes to test instruments. When you see a number, that doesn't necessarily mean that you're dealing with a number you're supposed to see. For example, nitric oxide can present as "false CO" to a carbon monoxide sensor. Test instruments that mistake nitric oxide as carbon monoxide will give a different reading than ones that don't pick up nitric oxide as CO, but that doesn't necessarily make either of them wrong. So, some instruments can give you false positives based on exactly what they measure. On the other hand, false negatives may have to do with poor sensitivity. A common case happens with leak detectors; on occasion, a leak detector won't be sensitive enough to pick up a leak. You can't just say that a set of numbers on an instrument absolves you of responsibility for errors; you must understand the instrument, what it measures, and its sensitivity to use it appropriately. Being rigid in terms of specifications is also a mistake when communicating with customers; customer satisfaction is the goal, and it's okay if their comfort needs deviate from the specifications a bit. Overall, accommodation and mental/financial investment in your tools are the keys; for the sake of the customer, we need to make acceptable compromises, and that's something you must factor into your measurements. Bill and Bryan also discuss: NOx filtration Bacharach PGM-IR Personal protective CO detectors and overloading Laboratory-grade instruments vs. normal test instruments Getting valid wet-bulb readings and using sling psychrometers Analog gauge variables and inaccuracy Lab testing and controlled conditions Ductwork in conditioned spaces Flow hoods Using our senses Olfactory fatigue Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Jul 2, 2020 • 56min
Going Deep on IAQ Sensors and Instruments
Bernadette Shahin of Aeroqual joins Bryan and Kaleb as they all dig very deep into indoor air quality (IAQ) sensors and instruments. They also cover the certainty and uncertainty of measurements. Reference method instruments generally have to operate within a set of parameters, notably a temperature range. Gas laws make the gases act differently, so you want the temperatures and pressures to stay within a range that allows you to measure the air conditions effectively. While we can use reference methods for full-scale instruments, there are no reference methods for IAQ sensors. The only way to make something close to a reference method on IAQ sensors is to use the near reference method. We measure humidity and temperature, and we do an atmospheric chamber and calibration. You have to pair sensors within an instrument to have a product that properly senses conditions. Measuring indoor air quality is important because we spend 90% of our time breathing indoor air with very little fresh air. Air pollutants build up in indoor spaces, and you could spend time in environments with harmful VOCs, allergens, and bacteria. Most people don't have the means of using HEPA filters or fresh air mixing in their homes; so, we need to focus on other solutions to control indoor air quality. Those solutions include air purifiers, but they also include sensors that monitor the air quality. One such sensor is the photoionization detection (PID) VOC monitor. With sensors, we must also think about sensitivity; we want the sensor to measure what it's supposed to measure in the amounts it's supposed to measure. Bernadette, Bryan, and Kaleb also discuss: Barometric pressure instrument calibration Algorithmic adjustments Sick building syndrome Formaldehyde off-gassing, ozone, and CO Aeroqual's solutions for BTEX Automatic baseline correction R2 factor AQI Automating IAQ strategies Pricing Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Jun 25, 2020 • 1h 19min
VRF and VRV Piping and Installation Overview
Jordan Cummings is back to discuss some of the most important points in the proper installation of VRF and VRV systems. We especially cover piping best practices. When it comes to piping, the biggest concerns on VRF and VRV systems are making sure the piping can handle the refrigerant velocity and ensuring proper oil return. Most VRF systems use PVE oil, but you still want to be cognizant of oil type, as not all manufacturers use PVE. You must consider fittings, length, and elevation changes when you pipe a VRF or VRV system. In our suction line, we want minimal pressure drop because too much suction drop reduces the mass flow rate through the compressor. You also need to think about avoiding too much of a pressure drop on the dual pressure line when it sends refrigerant to the compressor. You want your piping to be below the connections on the outdoor unit. The piping should be pitched up towards the unit when the outdoor unit is elevated on a stand. Of course, you'll also want to be mindful of where you place the outdoor units; the units should avoid the elements and be mindful of any awnings above. VRF/VRV systems come together at a variety of joints, including REFNETs and wyes (multi-chassis kits). Indoor units use REFNETs, which are basically engineered, balanced wyes. Outdoor units use typical wyes. Positioning these joints also makes a huge difference when it comes to proper feeding. Jordan and Bryan also discuss: Pipe sizing with software Dual pressure line PVE vs. POE oil Miscibility and oil carry Air-cooled vs. water-cooled condensers Condensate drains and trapping Reduced pumping/flow on water-cooled condensers External static pressure Alarms Piping limitations Cross piping on the branch selector box Expansion valve staying shut Pipe expansion 550 PSI, 24-hour pressure test Testing as you go Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Jun 18, 2020 • 55min
Time Management for HVAC Techs
Bryan and Eric Mele have a relaxed conversation on time management on the job. They also explain how to manage time in life as a whole. Some people are naturally fast because they cut corners in the name of time management. Instead, something Eric has learned to do is optimize his processes. He gets his work done a lot more quickly because he knows how to get the most out of the trips to his truck. Eric is also familiar with the tasks to perform them confidently, and he knows which diagnostic tools he'll probably need. Overall, repetition leads to efficiency. There are also plenty of ways to streamline evacuation and recovery. For example, Eric recovered refrigerant by piercing the liquid line from the air handler. His setup consisted of two charging hoses, a line dryer, and a recovery machine; it was an economic way to save his tools and recover refrigerant in the rain. Eric has done a lot of installs with people of varying experience levels. If there's one thing he learned, it's that you can streamline the process by starting at the outdoor unit, getting the old unit out, and getting the new unit set. The entire time, only one person should be working on the one-person jobs while the other gets supplies and makes preparations as needed. When it's time to work on the new unit, one person can work outdoors while the other works indoors. Eric and Bryan also discuss: Diagnostic tools to keep close or go without Dealing with paperwork Scavenging and saving small parts Cleaning the drain pan Pulling a vacuum through difficult fittings Working with people of diverse experience levels Using tin snips Efficiency and payment Work-life balance Prioritizing parts of your life Working with cranes Learn more about Refrigeration Technologies HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.