Aloha… sitting on a plane heading to Maui as I type this 
Hay William.
In the posts that follow your question, it is obvious that thermodynamics as pertaining to HVAC is complicated and can be confusing. My comment was about the information Ryan was using from the internet (which I downloaded and reviewed). I just didn’t like the author’s use of terminology.
Warm; is a relative term for one. Gas coming out of the coil can be warmer than the saturated temperature of the coil, but it is not warm to the touch (which is you guys perspective if you touch it).
“Can Be” is important to you guys determining if the unit is running correctly. That “warm” gas can be cold because of a dirty coil, over charged, metering device adjustment, etc. If your looking for “warm” and find it, there “is” something you need to look into as it should feel like a cold beer.
As far as evaporation; we primarily perceive evaporation as water boiling out of a pot on the stove, or water drying off the roof after a rain. Water is changing state from a liquid to vapor. H2O is moving into and mixing with the surrounding air. HVAC is a “Closed System”. There is no air in the HVAC system (there better not be anyway). It changes state and is the same substance as the liquid it came from.
“Evaporator Coil” and the “State of Refrigerant” (evaporation) are not the same thing.
You are talking about a piece of equipment or your talking about the refrigerant.
Confusing right?
So why does it matter (to me anyway)?
Because the State of Refrigerant does not evaporate directly from a liquid to a gas as it passes through the metering device like a carburetor or fuel injector. There is liquid in the coil more than 3/4 through the coil still.
Your client will be confused when reading your report anyway, so does all this really matter? Well, some HVAC guy is likely referred in the report. Will he understand you? What will be his perception of you through your report. Will he say you don’t know what your talking about? Who is he saying this to? What will be the perception of this and the rest of your report? Only matters if it matters to you. Sometimes the less you talk about, the better off you’ll be.
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Thermodynamics is the center of the worlds creation and it’s survival! It can not be expected to be easy to understand.
Try this article. It seems to be a more simple read.
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And here we have the “Real Science” of global warming! 
To save the planet, you must die…
Entropy and the Second Law of Thermodynamics
The degree of randomness or disorder in a system is called its entropy. Since we know that every energy transfer results in the conversion of some energy to an unusable form (such as heat), and since heat that does not do work goes to increase the randomness of the universe, we can state a biology-relevant version of the Second Law of Thermodynamics: every energy transfer that takes place will increase the entropy of the universe and reduce the amount of usable energy available to do work (or, in the most extreme case, leave the overall entropy unchanged). In other words, any process, such as a chemical reaction or set of connected reactions, will proceed in a direction that increases the overall entropy of the universe.
[[Hide explanation]](javascript:void(0))
This is actually a pretty crazy concept, if you extend it to its logical conclusion: that someday, all of the usable energy in the universe may have been converted to unusable energy (heat). This state has been suggested as one possible fate of the universe, and it’s sometimes called the “heat death of the universe.” However, it’s not clear to physicists that this is actually what will happen. And even if it does, it won’t be for another 10105610105610, start superscript, 10, start superscript, 56, end superscript, end superscript years or so – so not something to keep you awake at night!
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But energy transfer happens simply from the sun’s radiation, no? All across the electromagnetic spectrum there is the transfer of energy
Thank you, David! Thanks for all of your detailed responses! And the extra bits, too!
Understanding how everyday objects, like the various systems that keep our homes in good condition, is thoroughly fascinating. My concern, and goal for that matter, is being able to understand the operation of these various systems and their components to better convey to my clients, and any subsequent contractors that might utilize my report for future corrections, the overall condition and functionality of a building’s systems.
It’s my belief that if I spend a lot of time now understanding well the complexities of each system, when my observations, deductions, and mistakes don’t effect others, I will be better equipped to not only provide a better product, but also have a strong, solid foundation for which to grow from more easily in the future.
I say all that to say that I really appreciate the extra bits you’ve given. They’re helpful by filling in the little gaps that might not otherwise be covered in the courses here.
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Here, here
There was a very good video with Joe Listrebruk (sp?) on energy transfer through the building envelope. I think it might have been in the insulation course. Anyway he stated that the newer houses with lots of insulation (air tight) have poor energy transfer and don’t last as long as older houses with poor insulation.
It might be good if videos like that one were accessible to members outside of the individual courses. Is that possible @gromicko
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Upvote!! @gromicko