Testing a Thermocouple
First, a thermocouple is not a flame rectifier like a modern flame sensor. A thermocouple actually generates a millivolt potential difference when it is heated by a flame—just to get that out of the way for any of you newer techs who are used to modern flame sensors. With higher efficiency gas-fired equipment being the […]
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AHR NATE Class + Test
Title: NATE Testing & Review Description: Bryan Orr with HVACRSchool.com will offer a general, technical NATE review from 8am-11:30am and proctor a session of North American Technician Excellence (NATE) technician certification testing in the afternoon from 1pm-5pm. The Review will cover elements of the CORE, Air Conditioning and Heat Pump exams and how the concepts apply […]
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HP, Motor HP, BHP, Motor Watts
Brake horsepower (BHP), motor nameplate HP, and the actual electrical power (watts) a motor will consume are different but related concepts. They can get confusing. So, we will tackle them one at a time. Let us start with simple definitions of work, power, and horsepower. Work = distance in feet x force in pounds, both […]
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ACFM, SCFM, & Baseball dents
This is a VERY in-depth look at ACFM vs. SCFM and why it matters to airflow measurement from Steven Mazzoni. Thanks, Steve! Imagine your job is to figure out how fast baseballs were traveling before they hit a sheet-rock wall. The only method you have is to measure the depth of the dent left in […]
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Ain’t No Fooling With Free Cooling (Tales of the Economizer)
This article was written by Gary McCreadie from “HVAC know it all.” You can learn more about Gary and his tips and growing community on Facebook and LinkedIn. What is an economizer?  Simply put, it is a mechanical device designed to reduce energy consumption, whether it be fuel, electricity, or other. According to Wikipedia, the first […]
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Like a Bull in a China Shop – An Oversizing Story
This article was written by Genry Garcia of Comfort Dynamics, Inc. Thanks, Genry! This is a piece about oversized air conditioners. Though the symptoms and consequences of oversized heating equipment are similar to those of air conditioners, you’ll notice that the focus throughout the article will be on the cooling side—specifically from the perspective of […]
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The 10 Commandments of the HVAC/R Technician
One trait I’ve seen with good technicians is that they take their jobs VERY seriously, but they learn not to take themselves too seriously. A few months ago, I had someone tell me online that I must think I’m the A/C “god” because I’m always telling everyone the “right” way to do things. This got […]
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Accumulator & Burnout Considerations
The suction line accumulator is designed to keep liquid refrigerant from entering the compressor while still allowing for oil return. The trouble is that if the oil return port/screen clogs, the accumulator can fill with oil and actually cause the compressor to fail. In addition to that, it can hold contaminated oil in a burnout. […]
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Some Range Hood IAQ Thoughts
This article was written by my good friend Neil Comparetto, a contractor and industry influencer who is helping shape IAQ for the HVAC industry in the US for the better. Thanks, Neil! Indoor air quality (IAQ) monitors can tell you a lot about the air you are breathing. We find that the information is valuable […]
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