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To Humidify, or to De-humidify?

  1. May 29, 2005 #1
    I went to my local DIY store (hardware store) today and they were doing a special offer on De-humidifiers... On the same shelf, they were selling Humidifiers!!

    Which one should I buy?
    Do I want to be Humidified or Dehumidified??

    Should I buy both and let them fight it out in a sealed room??

    Which would you rather be - humidified or de-humidified? Perhaps I should start a poll? :confused:
     
  2. jcsd
  3. May 29, 2005 #2

    Evo

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    The usual needs are a humidifier in the winter to replace moisture removed by heating and dehumidifier in the summer, when humidity is more of a problem.
     
  4. May 29, 2005 #3
    So that's both then!

    Life is SO complicated sometimes....
     
  5. May 29, 2005 #4

    matthyaouw

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    the question is- do you really need either?
    My house needs a dehumidifyer (2, actually, plus extractor fans) because we have a problem with damp and mildew. Lack of humidity never seems to be an issue for us.
     
  6. May 29, 2005 #5

    Danger

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    Awww... that's sweet. They both have someone to play with.

    I think that the most practical way to dehumidify your house is to pump it full of liquid nitrogen. Then hit the air with a hammer and shovel it out before it thaws.
     
    Last edited: May 29, 2005
  7. May 29, 2005 #6
    I like this idea. Who would win in a fight in a sealed room, a humidifier, or a dehumidifier? You could take bets.
     
  8. May 29, 2005 #7
    lol I have both, here in Michigan, being surrounded by water, summers can be really hot and humid. I have a whole house air conditioner, but its expensive to run. So sometimes it makes it feel much cooler by just running the de-humidifier.
    :blushing: I just need to remember to empty it
     
  9. May 29, 2005 #8
    I could plumb the dehumidifier into the humidifier so that I wouldn't have to fill up or empty either. That might work.
     
  10. May 29, 2005 #9

    Gokul43201

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    We do both for our lab. We need a constant humidity of 45% (+/-5%) all year round, so we humidify during the winter (when ambient humidity at room temp can be as low as 5%) and dehumidify in the summertime (the building AC does most of the dehumidification, but we need to go just a little further to get within our allowed range).

    Normally, around 40% to 60% is considered comfortable, for human habitation (at about 20C or 70F).
     
  11. May 29, 2005 #10

    Gokul43201

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    Our building (physics dept) is terribly old and has a virtually dead HVAC system. This simply does not give us the required temperatures for our cleanroom when outdoor conditions fall within a specific narrow range. Every year, for a couple of weeks we need to achieve additional cooling, beyond what the building HVAC system gives us. We do this with liquid nitrogen. We gave up on promises to fix the HVAC and designed and installed a PID controlled delivery system that pours LN into a rack of stainless steel baking trays mounted inside our supply duct. We now have beautiful temperature and humidity control, 365 days a year.
     
  12. May 29, 2005 #11

    Danger

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    Dang, it's embarrassing when one of my jokes turns out to have a practical application. :redface:
     
  13. May 29, 2005 #12

    Gokul43201

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    I'm guessing this is a problem only in the summer. Normally, a healthy air conditioner will provide outlet air at a dew point of no more than 50F (typically about 40 to 45F). This corresponds to a relative humidity value of 50% which is comfortably low. Adding in the moisture produced from human respiration and perspiration will make this number no more than 60%. If the humidity is, in fact, much higher than this, I suspect there may be a problem with your air conditioner.
     
  14. May 29, 2005 #13

    Moonbear

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    I only need a humidifier in the middle of winter. Some people prefer a dehumidifier in summer, but humidity doesn't bother me. Of course, depending on where you live, some people need a humidifier in the bedrooms and a dehumidifier in the basement.
     
  15. May 30, 2005 #14

    russ_watters

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    So, then what do you do in the spring and fall? :devil:
     
  16. May 30, 2005 #15

    Moonbear

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    Open the windows! :biggrin:
     
  17. May 30, 2005 #16
    I'd almost have to say, if you don't know which one you need, you don't need one. I live in a basement apartment, and the need for a dehumidifier is readily apparent, especially in the bathroom (no fan or window). Without the dehumidifier, it doesn't take long for mold to start growing on the ceiling. :grumpy:

    If you're really unsure and concerned about it, buy yourself a hygrometer. I picked one up for about $2 at my local Wal-Mart.
     
  18. May 30, 2005 #17

    Evo

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    Originally Posted by russ_watters
    So, then what do you do in the spring and fall?

    Yep!
     
  19. May 30, 2005 #18

    Moonbear

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    Is that even up to code? Here, building code requires all bathrooms have to have either a fan or window.
     
  20. May 31, 2005 #19
    We no longer have the need for a humidifier in the winter because we have a fish tank. This seems to add enough humidity to keep down static shocks, dry hair, sinus problems, etc, without adding a humidifier. In the summer, we use our central air, but our basement has two dehumidifers that we run all season.
     
  21. May 31, 2005 #20
    International Mechanical Code requires 20 cfm continuous or 50 cfm intermittant mechanical ventilation, or you can prove that natural ventilation can be provided by operable windows that have enough open area to ventilate the space.
     
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