Sweeping with Nitrogen
Two days prior to this article being published I sent one out about the popular fallacy that nitrogen “absorbs” moisture. That tech tip went out at 7 PM eastern time like usual, and I was sitting on the couch watching something on the Food network (like usual). At 7:10 PM I get a call on my cell […]
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Does Air or Nitrogen Absorb Water?
There are many examples of teaching using metaphor to help someone get a grasp of 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 […]
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How (and Why) to Flow Nitrogen While Brazing
When I started in the trade, the idea of flowing nitrogen while brazing was nothing more than the punchline of a joke. Like pulling a vacuum with a micron gauge or proper recovery, it was a wink and nod proposition rather than a real practice. I've had to unlearn many bad habits since those early […]
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Non-noncondensables
  Flowing nitrogen while brazing and pressuring with nitrogen are great practices, but putting nitrogen in with the refrigerant? Not so much. Nitrogen is a “non-condensable” gas because it cannot be condensed (under normal conditions), but nitrogen isn't the only non-condensable. First, let's talk about what a non-condensable gas is. Any gas that does not […]
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Triple Evacuation and Nitrogen FACTS
This article was written by longtime contributor and RSES CM Jeremy Smith. Thanks, Jeremy! Nitrogen doesn’t absorb moisture like many techs think that it does, and I think that we, as technicians, need to reevaluate the reasons for the “triple evacuation” process. OK. Hold on, now. Put down the pitchforks and torches, and give me […]
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Start Flowing Nitrogen Sooner
My technician (and brother-in-law), Bert, made a good point today. (It's hard for me to admit it, but it's true.) When he needs to open the refrigerant circuit to make a repair, regardless of whether he is recovering or pumping down, he pulls out his nitrogen tank and his regulator. (We like the VN500 shown […]
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Is Flowing Nitrogen While Brazing Really Important? – Live Video 2/4/2017
In this live video Bryan talks about Flowing Nitrogen Reasons techs give not to flow nitrogen Reasons that some cases create more carbon than others Demonstration video by Tim Bagnall
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