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HH vs. EK Filter-Driers: Technical and Field Comparison
3 Ways to Reduce Compression Ratio in a Heat Pump
Best Practices to Conserve A2L Refrigerants in a Shortage
High-Pressure vs. Low-Pressure Shell Scrolls: A Deeper Dive
Should the Float Switch Break R or Y?
Don’t Drive Drowsy
Flex Ducts: Peeling Back the Layers
Solving Delta T
Donโt Fall for Unsafe Practices: Heights in HVAC
Why Square Footage โ Tonnage – Short #276
Combustion vs. Compression – Short #275
HVAC In the Northeast w/ Leo & Paul Sharkey
Superheat in Heat Mode: Why Heat Pumps Get Weird – Short #274
What We Learned From NCI Duct / Balancing Training
HVAC Systems for Architects: Making Sense of the Alphabet Soup – Short #273
Sizing Breakers and Conductors (for HVAC) โ Have Things Changed?
Absorption Cooling – The Rise and Fall and Rise – Short #272
Combustion Analysis w/ Tony G.
#hvac
Tech Tips:
When we think of HVAC system components, the big four come to mind: evaporator, compressor, condenser, and metering device. However, there are several accessories that keep the HVAC system working as intended, and the filter-drier is one we cannot ignore. Filter-driers protect HVAC/R systems by removing moisture, acids, and debris from refrigerant. In typical residential […]
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Weโve talked about compression ratio a lot over the years. Compression ratio is the number you get when you divide the absolute head pressure (PSIG + 14.7) by the absolute suction pressure (PSIG + 14.7). It measures the efficiency of a compressor, and lower numbers indicate that the compressor is moving more refrigerant while consuming […]
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If you own your HVAC company or are involved in management, you may have realized that our industry is currently facing a shortage of new A2L refrigerants, particularly R-454B and R-32. Our own company has faced limited availability and long lead times, mainly due to supply chain disruptions and the increased demand now that our […]
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I want to share something that came up in a recent discussion with Roman Baugh about VRF systems, and it made me realize I might have had a blind spot regarding scroll compressor designs. We were talking specifics, and he brought up high-pressure shell compressors. My immediate thought was, “Hold on, aren’t scrolls low-pressure shell […]
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There are three things we never discuss at the dinner table: religion, politics, and which wire to break with your float switch. A float switch fills with water whenever there is a drain backup, and it breaks power to one of the low-voltage wires. We clearly want the HVAC system to stop producing more condensate, […]
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Being in an industry that requires a lot of travelโlocal or regionalโcan be a great thing for people who enjoy driving. It also comes with several more risks and opportunities for roadway accidents than someone who just has a round-trip commute to a single location every day.ย Weโre all aware of the issues of texting behind […]
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A few times in the past, weโve heard the phrase โthe house is the biggest ductโ because of the way air moves through it. Well, we can take it a step further and see that there are similarities that go just beyond air movement.ย A building has several layers to keep things like moisture, heat, and […]
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Delta T is the difference in temperature between two points of the same medium. It is commonly used by scientists and engineers to analyze the amount of heat transfer in a system. In general HVAC terms, it is the measurable change in temperature between an air input and air output. However, it could also be […]
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DISCLAIMER: HVAC School is NOT an official OSHA safety training resource! Although we provide safety tips in good faith, neither this tech tip about the hazards of working at heights nor any other training on our website is a substitute for safety training from an authorized OSHA training source. Many things may deter people from […]
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Videos:
Podcasts:
๏ปฟ๏ปฟ In this short podcast episode, Bryan dives a bit into equipment sizing rules of thumb and why square footage does NOT equal tonnage in today’s world. Many rules of thumb exist in the industry, and one is a load calculation rule stating that you can size the HVAC for a house at 500 square […]
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๏ปฟ๏ปฟ In this short podcast episode, Bryan covers the history of the great heating debate: furnaces vs. heat pumps or combustion vs. compression. He also gives a breakdown of each other’s strengths and gives his two cents on the winner of the debate. Fire kept humans warm for much of history, but engineers developed a […]
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๏ปฟ๏ปฟ In this engaging episode of the HVAC School podcast, host Bryan Orr sits down with Leo and Paul Sharkey, a father-son duo of mechanical engineers who made the leap into the HVAC business. Leo and Paul share their remarkable journey of purchasing an HVAC company in September 2020 and quadrupling its revenue within five […]
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๏ปฟ๏ปฟ In this short podcast, Bryan answers a listener-submitted question and explains why heat pumps get a bit weird: when it comes to superheat in heat mode. He also explains how we can move heat from outdoors to indoors, even in temperatures below freezing (cold temperatures just have less heat, not zero heat). In order […]
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๏ปฟ In this engaging and informative episode, Bryan sits down with Elliot to discuss his recent training experience with the National Comfort Institute (NCI), covering two intensive courses on duct system optimization and residential air balancing. The conversation offers valuable insights for HVAC professionals looking to improve their technical skills and provide better service to […]
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๏ปฟ๏ปฟ In this short podcast, Bryan answers a question submitted to HVAC School by an aspiring licensed architect who wanted to learn more about the many different types of HVAC systems. The three main buckets of HVAC systems are air-to-air, water-source, and air-to-water. Air-to-air systems move air around to remove heat from one space, and […]
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๏ปฟ๏ปฟ In this essential episode, Bryan Orr sits down with Elliot, the residential install supervisor at Kalos Services, to unpack a critical issue that’s causing confusion among HVAC technicians, electricians, and inspectors alike: the new standards for breaker and conductor sizing on inverter-driven equipment. The conversation was sparked by Elliot’s frustrating experience of having two […]
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๏ปฟ๏ปฟ In this short podcast episode, Bryan goes on another history journey, retelling the story of the rise and fall and rise of absorption cooling.ย Some of the first HVAC/R engineers cooled buildings with fire; they used absorption refrigeration, which ran on heat instead of electricity. In the early 1800s, French scientist Michael Faraday showed that […]
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๏ปฟ๏ปฟ In this comprehensive training session from the symposium, Tony Gonzalez, Training Director at Fieldpiece, delivers an engaging and practical guide to combustion analysis for HVAC technicians. With 25 years of experience at Fieldpieceโfrom warehouse worker to training directorโTony brings both technical expertise and real-world application to this 50-minute interactive session focused on the company’s […]
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