I Really Want to Learn More!
This is an open letter sent to staff at Kalos Services. Hey Everyone, First, I want to remind you that you are in no way obligated to read company emails or do anything work-related when you aren’t working. So, if you don’t want to be bothered by this on your day or time off, then […]
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Lifting Techniques Part 1 – Basics
This is ANOTHER series by Senior Refrigeration Tech (and prolific writer) Jeremy Smith. Pay attention to this one, folks. I know rigging and safe lifting practices may be boring to some of you, but it could very well save your back or your life. Disclaimer This article is written by a technician representing his real-world […]
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What is a DIN Rail?
If you do any larger commercial work, you’ve probably seen a DIN rail without knowing what it is called. It is simply a mounting standard that originated in Germany in the 80s and slowly worked its way over here. DIN rails can be used to mount terminal blocks, relays, starters, breakers, and just about anything […]
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Use Your Senses First
A good technician uses their senses before they use diagnostic tools. Is your suction line abnormally cold? Make sure the evaporator coil isn’t frozen, and inspect for obvious airflow issues like a dirty filter or evaporator coil. Is your liquid line abnormally warm to the touch? It could be a dirty condenser, condensing fan issue, […]
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TXV Power Element of Surprise
The TXV powerhead or power element is the part of the valve that sits on top of the valve to which the sensing bulb is attached. The powerhead provides the opening force for the valve by translating force from the bulb to a diaphragm in the element that forces the valve open. The sensing bulb […]
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Fire Damper Tips
Tech Brandon Livingston posted about fire dampers and took some photos shown here. He gave me permission to share this here, and his original post inspired this tip. Thanks, Brandon. The picture on the left shows the situation before the damper was opened. The right image show what happened after it was opened and a […]
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Can A Motor Run Backwards by Swapping Run & Start?
Can a single-phase motor run backward when start and run are swapped? The answer is (generally) yes. Is the motor designed to run backward by simply swapping run and start? The answer is (generally) no, with a few notable exceptions. Before we jump in, this article has two purposes. #1 – it helps you understand […]
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The Dangers of the “Diesel Effect” (Compressor Explosion)
My friend Ami Slavin requested that I write about this important topic in response to the horrifying videos showing up online of death and gore associated with compressors exploding. He pointed out that the “diesel effect” can be the cause, so let’s explore what may be—and likely is—leading to these horrible incidents. In a diesel […]
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Troubleshooting for HVAC/R – Repairs, Reevaluation and Wrap up
This article is part 5 of a 5-part series on troubleshooting by Senior Refrigeration and HVAC tech Jeremy Smith. This step might be the most challenging part of troubleshooting. We’ve got a “Most Likely candidate” for the trouble, but we don’t know for certain that’s what is wrong. So, we have to combine our customer […]
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