Equipment Grounding
The grounding and bonding process is important, and it's a fairly broad topic. In HVAC/R, we generally just need to make sure that we properly connect the conductors (wires) provided to the proper connection points in the equipment and occasionally the disconnects. These connection lugs or green screws are rated for grounding so long as […]
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Duct Leakage Can Be Costly
This tech tip was written by one of the best all-around HVAC minds out there: Neil Comparetto. I think that we all can agree that duct leakage is not ideal. Our job is to condition the space. If we can’t control the air, that becomes difficult. On top of that, anytime the ducts leak, you […]
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Ideal Gas Rulebreakers
Breaking the Sound Barrier So, what do you think of when you hear an “ideal gas?” R22, R12 maybe… natural? Take a look at the F-18 above. It's breaking the sound barrier, and that cloud is a shockwave. It has nothing to do with this article, but I think it's pretty darn cool! An ideal […]
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Get an EEV Open (Like Magic)
This tech tip comes from our contributor, compressor decapitator, and super tech Ulises Palacios. Many ductless systems and some high-efficiency unitary systems have electronic expansion valves. If you find one that is stuck closed, you may be able to get it open temporarily by putting a strong magnet like the one shown above on the […]
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What Does “Air Free CO” (Carbon Monoxide) Mean?
  Almost everyone knows that CO (carbon monoxide) is really nasty stuff and nothing to play around with. Humans will often begin exhibiting symptoms of CO poisoning at 200 ppm (parts per million) of CO in a space. Studies have also shown that the effects of CO exposure can accumulate over time, resulting in health […]
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Density of Air & Water Part 2
Here is part 2 from Michael Housh from Housh Home Energy in Ohio. Thanks, Michael! This is part two in a series on a deeper look into the sensible heat rate equations. You can find the first article here HERE if you missed it. This article will dive deeper into the density of “standard air” […]
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You’re Grounded
One of the most common questions we get from techs is about using a voltmeter to diagnose a high voltage circuit. It's especially tricky when a tech is used to working on a low-voltage or 120V circuit, where there is a clear “hot” side of the circuit and a clear “grounded” side of the circuit. […]
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High Capacity Amperage Measurement
We had a situation a few months back where we needed to monitor amperage on a grocery store panel over a period of time. The trouble was that we needed data-logging capability AND accurate measurement at 600+ amps. Finding an all-in-one solution proved to be quite expensive. Luckily, my friend Jim Bergmann happens to own […]
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Pool Heat Pumps, The Basics
Note: My brother Nathan wrote this a few years back, and I only did some minor editing. A pool heat pump is essentially a water-cooled air conditioner in reverse. It usually has a large air evaporator on the outside that looks like a condenser coil and a heat exchanger (usually tube-in-tube) on the inside. A […]
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