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Absolute Humidity

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  • LasabarLasabar Everyone, Registered Users Posts: 4,457
    dutyje:
    Lasabar:
    madurofan:
    Well unless its passive. What is your humidification lassy?
    Got me two large discs of "Heartfelt Humidity Beads" at 70% but they are a little under-filled for i want to gain 67%
    when you say "under-filled" -- you mean some of the beads are white? or do you mean it's not filled all the way up to the top with distilled water? The latter will keep you running high for qutie a while.
    I mean one disc is 80-90% clear and one disc is 70% clear
  • dutyjedutyje Everyone, Registered Users Posts: 2,263
    then what you're seeing doesn't make sense unless your hygrometer measures absolute humidity (I thought this was rare in a non-commercial hygrometer) or maddy's air conditioner theory applies.
  • kuzi16kuzi16 Everyone, Registered Users Posts: 14,471
    i find that if the air is more humid in general (summer months) the beads do better way under charged. about 10% (if that) of my beads are clear at the moment. im at exactly 65% ... and they are 65% beads.
  • madurofanmadurofan Everyone, Registered Users Posts: 6,152
    How the hell did you get your beads to dry out? I've taken the hair dryer to them for so long they were scolding hot but still not dry. I let them sit out for a few days no more dry than when they started.
  • kuzi16kuzi16 Everyone, Registered Users Posts: 14,471
    i crank up the AC and set them in front of a vent for a few hours. worked for me.
  • madurofanmadurofan Everyone, Registered Users Posts: 6,152
    hmmm ... might give that a shot. or maybe use the cool option on the hair dryer as well.
  • kuzi16kuzi16 Everyone, Registered Users Posts: 14,471
  • urbinourbino Everyone, Registered Users Posts: 4,517
    Hair dryer on low worked for me, maddy.
  • VidarienVidarien Everyone, Registered Users Posts: 246

    It seems like some are really interested about this topic, im a chemical engineer and this is my bread and butter, so ill recap and explain in detail most of what was mentioned for the reallllllllly curious (and because i clearly have nothing better to do!).

     

    - The difference between absolute humidty and relative humidity is based on temperature.  The reason its a relative humidity is because its relative to that temperature.  Humidity, as a measurement of the partial pressure of water per volume of space (or, a percentage, as you always see it), is completely dependent on the temperature of the volume that it is in.  As the temperature goes up, the pressure of that water must rise as well, given the volume itself hasnt changed, via the ideal gas law.  (Theres exceptions to that rule, but thats far beyond the scope of the discussion here).  So, as a result, the maxium pressure of water in air increases, and water is absorbed into the gas phase via evaporation to meet that equilibrium.

     

    I know thats kind of confusing, but i'll leave it at, absolute humidity can not be measured with a percentage, it can only tell you how much water vapor is in a certain volume of space.  That in itself tends to be meaningless for common everyday uses, (aside of scientific/engineering calculations), which is why people make it relative to the dew point at a specific temperature, hence relative humidity.  At 0% relative humidty, there is absolutely no water vapor in the air, at 100% relative humidity, the air is completely saturated, and should any water vapor at all be introduced into the volume, it would immediately condense.  (Its why the outside of your beer gets wet!)  Actually, theres a little more to that, and it leads to exactly what some of you are wondering about, temperature changes in a closed humidor.

     

    So, like i explained above, the temperature of the volume (air) directly influences the relative humidity.  To answer someones question earlier, the changes in your relative humidity make perfect sense when temperature changes.  In a closed box, if the temperature rises 10 degrees, the relative humidity must go DOWN.  Heres why.  You have a pretty constant amount of water vapor in the humidor, and then suddenly..within a few hours your box is warmer.  Well, the capacity for water to remain in the vapor phase goes up!  As a result, the total humidity relative to the dew point (100% RH) must go down!.  Its like taking a glass of water and pouring it into a bucket, and then taking that same glass of water and pouring it into a tub.  The water in the tub is far less a % of the whole than with the bucket.

     

    Now, the reverse to answer another question i saw.  Say you had your humidor in the basement in a really hot house with all the windows open, and it was about 75 F down there, and you had a good 70% RH in your humidor.  Then you close all the windows, turn on the AC reaaallly low and forget about your humidor.  Well, the relative humidity is going to spike, because the capacity of water in the gas phase will go down quite a bit as your basement really cools down, and...if it hits the dew point (about 62 degrees assuming you were running at 70% RH)...everything from then on is condensed water in your humidor.

     

    Disclaimer: What I said above is in theoretical conditions.  It would happen eventually but not immediately because the temperature of the air inside the humidor wouldn't cool as fast as the basement air due to the wood seal.  How long it would take would involve me and a whiteboard with lots of numbers and symbols, and im not that crazy.

     

    I hope this serves the interest of those that really wanted to know the deal behind RH and humidors.

     

    Edit: I guess i misread.  I didnt see that someone said their RH went down along with temp.  If you meant in your house itself, then the AC explanation given was completely valid; if you meant inside your humidor, i would wonder if your humidor had a secure seal?  You probably wouldnt notice significant humidity changes in your humidor if it was hot and humid in the area surrounding it assuming a bad seal, given diffusion would be much slower.  But once AC was on, the difference would be much more pronounced.  This is just my opinion though.

  • pilot711pilot711 Everyone, Registered Users Posts: 176
    Great post! Very informative. Thanks.
  • kuzi16kuzi16 Everyone, Registered Users Posts: 14,471
  • madurofanmadurofan Everyone, Registered Users Posts: 6,152
  • dutyjedutyje Everyone, Registered Users Posts: 2,263
    Thanks, vidarien... that was very well written. Please stick around and give us information like this more often!
  • VidarienVidarien Everyone, Registered Users Posts: 246
  • madurofanmadurofan Everyone, Registered Users Posts: 6,152
    Thanks for that insight.
  • VidarienVidarien Everyone, Registered Users Posts: 246
    Sure.  Unfortunately, all of the things i'm saying are just theory.  The problem between science and the real world is, we dont keep our humidors in laboratory conditions.  Theres pretty much a countless number of other factors that can come into play, so its always possible the exact opposite of what I may suggest can happen.  To be tried and sure, if its important to me, i always test it out myself and dont leave anything to chance.
  • madurofanmadurofan Everyone, Registered Users Posts: 6,152
    Well theory is all we can ask for at this point and we appreciate your insight. Do you use beads?
  • VidarienVidarien Everyone, Registered Users Posts: 246
    Well, actually, im in the process of seasoning a new humidor with a seasoning packet (i've decided I do smoke enough to actually buy online/store them instead of driving to the B&M when im in the mood).  I was using the onboard device but I may switch to beads.  I overfilled the device last nice and the backing was weak anyway so it fell to the bottom and left a nice moisture stain.  I'm hoping that will dry out soon without any damage.  I'm starting to get myself paranoid about humidor warping, one of the lips on the side of the lid has a slight bit of empty space between it and the lid itself, and it keeps agitating me every time i see it.
  • madurofanmadurofan Everyone, Registered Users Posts: 6,152
    Stick a dollar bill in there and try to pull it through ... if its difficult its got a good enough seal, hows that science for ya? Despite what you may believe a perfect seal is not necessary nor desirable you want some air exchange just not enough to affect the RH.
  • VidarienVidarien Everyone, Registered Users Posts: 246
    Yeah, i couldnt just take it out, it required a little bit to pull the dollar through.  Sitting at about 69%/71 F in there, but, thats with the 84% seasoning packet still in it, i guess it still has some seasoning to go.
  • madurofanmadurofan Everyone, Registered Users Posts: 6,152
    Did you calibrate the hygro? Wait your a scientist, sorry
  • VidarienVidarien Everyone, Registered Users Posts: 246
    Calibrated and with a digital in there for backup after my analog calibration went sour.  The deviation of error on the analog naturally is quite high.
  • madurofanmadurofan Everyone, Registered Users Posts: 6,152
    Yea for the most part they're just really for decoration. Most of us on here just use digis for everything.
  • waterman3923waterman3923 Everyone, Registered Users Posts: 5
  • kuzi16kuzi16 Everyone, Registered Users Posts: 14,471
  • VidarienVidarien Everyone, Registered Users Posts: 246
  • waterman3923waterman3923 Everyone, Registered Users Posts: 5

    Thanks I will take out my cigars and put in the bowl of distilled water for a few days and follow your advice. I have no cigars over a few weeks old so I dont think anything will be hurt. Where can I get these crystals ( a link would be great) and would I use them in addition to or in place of my current humidification device?

    I got these instructions from where I bought my humidor: "Setup is very simple and you do NOT have to be as careful as you may think. Cigars are very forgiving. Simply wipe the inside down with Distilled Water - you can use a sponge or paper towel. Then pour Distilled Water into the humidifier sponge until it is full (you can also soak it in small container.) That's really it."

    I already know I need to get a larger humidor one that holds 300 to 500 cigars but I can't find one that I like and can afford lol. One of you mentioned having an aging humidor so a dumb newbie question. If I get in some cigars today how long should I have them in the humidor before they are at their best to smoke? Thanks for all the great advice.

    Charles

  • kuzi16kuzi16 Everyone, Registered Users Posts: 14,471
  • waterman3923waterman3923 Everyone, Registered Users Posts: 5

    Thanks kuzi its like another hobby I have in the beginning I had to read, read, read but I have one more question related to this topic. I found a "Le Veil Digital Humidification System"  for a really good price. Would something like this be a good investment? According to the ad description its totally automatic and I can set the humity to whatever I want to maintain my humidor at. Thanks again and I will go to Cigar 101 and do some reading.

    Charles

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