1. Welcome Hearth.com Guests and Visitors - Please enjoy our forums!
    Hearth.com GOLD Sponsors who help bring the site content to you:
    Hearthstone Soapstone and Cast-Iron stoves( Wood, Gas or Pellet Stoves and Inserts)

Humidifier... distributing moisture.

Post in 'DIY and General non-hearth advice' started by Bster13, Oct 27, 2013.

  1. Seasoned Oak

    Seasoned Oak Minister of Fire

    Joined:
    Oct 17, 2008
    Messages:
    3,726
    Loc:
    Eastern Central PA
    Once it goes below freezing RH drops fast outside as there not much evaporation goin on. Gets down pretty low around here.

    Helpful Sponsor Ads!





  2. Malatu

    Malatu New Member

    Joined:
    Nov 8, 2012
    Messages:
    84
    Water will evaporate as long as its not frozen. There is heat in 50 degree air, just not as much heat as 80 degree air.
  3. Malatu

    Malatu New Member

    Joined:
    Nov 8, 2012
    Messages:
    84
    Sounds logical but that's not how it works. Relative humidity is mostly a function of relative air temperatures not whether the air temperature is below freezing.

    And actually, the lower the temperature goes below freezing, the relative humidity of that same air goes up!
  4. STIHLY DAN

    STIHLY DAN Minister of Fire

    Joined:
    Jan 15, 2013
    Messages:
    656
    Loc:
    So NH
    I have been around and worked on a million humidifiers, Never have I come across one that had an outdoor temp sensor. They are all set to the humidity needed or wanted. If an operating rm needs 45% humidity, do you think it matters what temp it is outside. I believe you are not understanding your charts.
  5. STIHLY DAN

    STIHLY DAN Minister of Fire

    Joined:
    Jan 15, 2013
    Messages:
    656
    Loc:
    So NH
    Freeze dried.
  6. STIHLY DAN

    STIHLY DAN Minister of Fire

    Joined:
    Jan 15, 2013
    Messages:
    656
    Loc:
    So NH
    RH is the amount of moisture in the air. Temp comes into play with how much moisture the air can hold. The lower the temp the less moisture it can hold. Dew point!!!
  7. Malatu

    Malatu New Member

    Joined:
    Nov 8, 2012
    Messages:
    84
    Outdoor temp sensor? Not sure what you are talking about.

    Are you suggesting it's ok to keep your indoor humidity at 45% if it's -5 degrees outside?
  8. woodgeek

    woodgeek Minister of Fire

    Joined:
    Jan 27, 2008
    Messages:
    2,854
    Loc:
    SE PA
    I just use this calculator when I am confused...

    http://www.dpcalc.org/

    I just remember that 50%RH at 70°F is 100% RH at 50°F. If the dewpoint is over 50°F, and I open a window, it will increase the indoor humidity, and vice versa.
  9. Malatu

    Malatu New Member

    Joined:
    Nov 8, 2012
    Messages:
    84
    Just book marked it. Thanks!
  10. jdp1152

    jdp1152 Minister of Fire

    Joined:
    Oct 4, 2012
    Messages:
    769
    Loc:
    Massachusetts
    Yes. I have two heating systems with a humidifier on main floor. As long as your house isn't changing air 3x an hour the entire house should find the same level with proper air and moisture management.
  11. Hogwildz

    Hogwildz Minister of Fire

    Joined:
    Nov 3, 2006
    Messages:
    7,101
    Loc:
    Next to nuke plant Berwick, PA.
    The lack of attic ventilation also played a major role in that issue.
    BrotherBart likes this.
  12. Retired Guy

    Retired Guy Feeling the Heat

    Joined:
    Oct 27, 2011
    Messages:
    459
    Loc:
    Cape Vincent, NY
    Water will sublimate when frozen, basically the same
    jharkin likes this.
  13. JayD

    JayD Member

    Joined:
    Aug 22, 2007
    Messages:
    245
    Loc:
    35 miles north of detroit
  14. Bster13

    Bster13 Minister of Fire

    Joined:
    Feb 24, 2012
    Messages:
    810
    Loc:
    CT
    That is $230 and too ugly for my wife, haha.

    This is the research spreadsheet I have put together thus far:

    upload_2013-10-28_19-5-2.png

  15. Firedancer

    Firedancer New Member

    Joined:
    Oct 11, 2013
    Messages:
    92
    Loc:
    New Jersey
    Whata guy! :p
  16. BrotherBart

    BrotherBart Hearth.com LLC Mid-Atlantic Division Staff Member

    Joined:
    Nov 18, 2005
    Messages:
    29,062
    Loc:
    Northern Virginia
    One of these sitting in the air convection path handles this 2,500 sq. ft. two story barn just fine. And just needs to be filled once a day. Unlike the wood stove. In the Spring I buy the filters at Walmart when they mark'em down to five bucks to clear them out. During the season rinsing them in the sink in some bleach and water extends the filter life a lot.

    http://www.walmart.com/ip/Sunbeam-Cool-Mist-Humidifier/19536346
    woodgeek likes this.
  17. Bster13

    Bster13 Minister of Fire

    Joined:
    Feb 24, 2012
    Messages:
    810
    Loc:
    CT
    I can't find any specs on that sunbeam in terms of what sq footage it claims to cover, nor the gallons per day rating. Do you recall when you bought it?

  18. BrotherBart

    BrotherBart Hearth.com LLC Mid-Atlantic Division Staff Member

    Joined:
    Nov 18, 2005
    Messages:
    29,062
    Loc:
    Northern Virginia
    Bought it two years ago. Mine is when they made one with digital readouts and humidity controls. Too many people complained about them turning on and off too often over a one percent boundry so they just have a manual dial now. I don't know what sq. footage it claims to cover. Just what sq. footage it covers in this house. The tank holds a gallon and a half I think.
  19. woodgeek

    woodgeek Minister of Fire

    Joined:
    Jan 27, 2008
    Messages:
    2,854
    Loc:
    SE PA
    square footage ratings would be pretty useless, given the house to house variations in air leakage can be a factor of 3-5, easy.
    BrotherBart likes this.
  20. Bster13

    Bster13 Minister of Fire

    Joined:
    Feb 24, 2012
    Messages:
    810
    Loc:
    CT
    That's true. I was looking at the gallon per day output. But yeah, each home is different.
  21. woodgeek

    woodgeek Minister of Fire

    Joined:
    Jan 27, 2008
    Messages:
    2,854
    Loc:
    SE PA
    I got a 3 gal/day unit, and it is plenty for a decently airsealed 2300 sq ft place,
  22. Bster13

    Bster13 Minister of Fire

    Joined:
    Feb 24, 2012
    Messages:
    810
    Loc:
    CT
    So weird that I am seeing many more gallon/day for same sq footage (see my chart above).

    Another reason for oversizing was so that I can run the unit's blower on low and keep things quiet.

    But I guess if I buy something that i grossly oversizing, it would foster more mildew and mold.
  23. woodgeek

    woodgeek Minister of Fire

    Joined:
    Jan 27, 2008
    Messages:
    2,854
    Loc:
    SE PA
    I think about it a bit differently. You have a target RH, mine is 30%, since I have an older house I worry about condensation in wall cavities, etc. That is plenty to keep the furniture from falling apart, and on the low end of the 'healthy window' 30-50% RH. No matter what unit you get, you are gonna let it run on a humidistat, and play with the stat setting until you hone in on your target. If the unit is too small, you won't get there. If it is too big, it will cycle, and that can be more annoying than a smaller unit cycling less.

    I got a cheap unit (with a h-stat) that looks like BB's, and it can 'lift' the RH by about 10-15% over what it would be otherwise, going full out at 3 gal/day. Before I airsealed, I could put 3 gal a day in the air, and see **no effect** on a hygrometer (maybe a point or two). I suppose I could've paid a bundle to dump 10+ gallons (?!) a day into the air, but at some point it gets kinda craaazy.

Share This Page