I have long been curious about Humidifiers and Dehumidifiers. Why would you use either? What are the benefits? What are the drawbacks?
I never get a straight answer from the Home Improvement Outlets whenever I ask this, so I’m asking the Teeming Masses.
I can answer why for humidifiers: dry air is hard to breathe for some people, such as my father (who has asthma; he moved us to Florida because of the dry air up north), and myself (who has seemingly-chronic bronchitis).
I also get icky nosebleeds when the air is too dry.
As for dehumidifiers, those people don’t make sense to me. 
Dehumidifiers come in handy in dank basement situations. For example, my Mom recently converted the basement of her house into a finished bedroom. Unfortunately, it’s incredibly humid down there. How humid? Well, over the summer she left a box of envelopes in that room, and one day when she went to use one, she discovered it had sealed itself, due to the high amount of moisture in the air. So if you don’t want all your clothes to get mildewy, and all your books to rot, you run a dehumidifier to suck some of the moisture out of the air. We also sometimes run one in the garage to keep the books and papers stored out there from getting too dank.
Here’s an interesting description of how a dehumidifier works:
It points out that if you have an air conditioner, you don’t need a dehumidifier, because the a/c will dry the air all by itself. (Incidentally, that’s how we defrost the windshield of my little Tercel when it starts to fog up on the inside. The heat defroster just isn’t effective, so we turn the a/c on for about 30 seconds, and it clears the fog right up.)
Interestingly enough air conditioning was a side effect of de-humidifying. I’ve forgotten the particulars but early in the 20[sup]th[/sup] century a printer needed a way to de-humidify the air (the humid air would wreck their paper and screw-up the ink drying process). The solution not only de-humidified the air but cooled it as well…a double bonus for the printer.
In addition to the breathing thing, people who suffer from very dry skin (Mrs. ShibbOleth and the Boy would fall into this category) benefit from moist air. This is a problem in the winter, plus in the summer if the air conditioning does too good a job of dehumidifying. We usually just put a little room humidifier in the boy’s room. He also has a tendency towards bronchitis. Don’t know if dry skin and bronchitis are linked, though.
I never understood a DE-humidifier until I moved to Florida. The massive humidity will warp furniture.
Up north you can carpet shock your cat just by petting him without a humidifier in the winter.
On the other hand it would be fun to have one of each and watch them battle to the death
Here in Hong Kong during summer, you get mold growing everywhere - on walls, ceilings, in rarely-worn shoes, video tapes, CD’s etc. Air-conditioning dehumidifies pretty well, so it’s not essential to use a dehumidifier (which actually generate a lot of heat). But it’s a useful addition.
After being exposed to chemicals weapons in Iraq, I am left with a scarring in my trachea that remains very dry and painful in drier weather. I must consume massive amounts of water (milk helps, too) to make sure that my mucus glands produce enough mucus too cover the dry scar. Unfortunately that also means that I cough alot, usually a very dry, hacking, and painfully unproductive cough.
The humidifier helps keep my throat damp enough that I do not vomit from the coughing.
Now if I could only find an inhaler that allows me to breathe in a nice soothing and humid medication, and not just those stupid hormones.
We moved into a new house w/ a basement about 7 months ago. During the summer the cold water pipes running along the basement ceiling were always wet, to the point where water would constantly drip from them. This wasn’t because the pipes were leaking; it was because the pipes were cold, and water in the air condensed on them. To counteract this, we bought a dehumidifier. This solved the problem – after installing the dehumidifier, no more water condensed on the cold water pipes.
Thank you all for your information. I have now acheived Enlightenment.
Sigh… here in western Wisconsin you must needs have both. The relative humidity can range from 90% (with no AC)in the summer to 20% (forced air heat) in the winter. Either one is pretty miserable, and we have the cracked furniture to prove it. Not to mention the high electricity bills from alternating the humidifier and dehumidifier.
Happily, this year we could finally afford a new HVAC system that handles both problems… 50% all year round, ah bliss!
Minor Hijack , so if i remove or disable the heating coil in my dehumidifier i can use it as a air conditioning unit?
This year summer wasn’t too bad but they year before the heat and humidity was a killer.