Which Valve Do I Open First?
Testo 557 vacuum gauge and Appion core removal tools shown I've had a change of heart. Back in the early 2000s, during the big construction boom, I did many system startups on residential units for a large company I worked for. When installers ran the line sets prior to startup, they weren't always very careful […]
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Do You Need to Be Recovering Into a Vacuum?
This topic came up because I was testing out the new MR45 digital recovery machine. That machine goes off by itself when it hits a 20″ Hg vacuum. It's a cool feature, but it is good to know when that level of vacuum is overkill and when it's not enough according to EPA requirements. You […]
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Does Air or Nitrogen Absorb Water?
There are many examples of teaching using metaphors to help someone grasp how something works without being EXACTLY correct. Some examples are how we often use water flow to explain electrical flow or refrigerant circuit dynamics. It's enough like the way it works to get our heads wrapped around it, but there are many differences. […]
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Can Pulling a Vacuum too Fast Freeze Water/Moisture?
First, I want to give credit where credit is due. This post is made possible by the fantastic demonstration video by Neil Comparetto that I embedded below. Before you get bored and stop reading, I want to get the conclusion out in the air. Ice can form in a vacuum, but I still advise pulling a […]
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Scroll Compressor Pump Down, Megohm Test & Fusite Terminals
This tip will be like an episode of Columbo; we will start with the what and who and then get to the why. Don't pump down a scroll into a vacuum. Don't run a scroll in a vacuum. Don't run a high voltage megohmmeter or Hi-pot test on a scroll (As a general rule, don't […]
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What is a Micron?
To answer the question in the title, we use it as a measurement of pressure. REALLY, it is a measurement of distance. First, any scale CAN be used to measure vacuum (negative pressure) and positive pressure. The trick is knowing which is best suited for which and the size of the scale. Larger units of […]
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Testing the Leak Rate on Your Micron Gauge Itself
As a technician gains skill, they will learn that regularly testing your tools is a huge part of success. It isn't long in the field before techs find out that just because a meter or gauge gives a particular reading, it doesn't ALWAYS mean it is correct. Vacuum is one of these areas. Everything in […]
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Testing the Leak Rate on Your Micron Gauge Itself
As a technician gains skill they will learn that regularly testing your tools is a huge part of success. It isn't long in the field before techs find out that just because a meter or gauge gives a particular reading it doesn't ALWAYS mean it is correct. Vacuum is one of these areas. Everything in an […]
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How Long Should I Evacuate a System?
This article was written by Jim Bergmann with MeasureQuick. Anyone who has ever picked up a vacuum pump has asked or been asked this question. To be truthful, it is like asking, “How many licks will it take to get to the center of a Tootsie Roll Tootsie Pop?” In the words of the wise […]
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