home-made dehumidifiers

Yesterday I posted about a/c and how humidity is such a burden for the unit. Today we shall learn about homemade dehumidifiers, a concept I had never thought of until Ruben googled it last night. A timely topic for the humid month of August.

In my five minute research into the topic, there appear to be two basic kinds of homemade dehumidifiers: one uses charcoal and coffee cans with holes poked in the lids and the other employs road salt (calcium chloride), cheesecloth, and plastic buckets. Since the second kind requires more things I don’t have, and probably a trip to a store I don’t normally go to, I think I’ll begin my own experiments with charcoal. An additional advantage to charcoal is that it is also a natural deodorizer. See further ways you can implement the dehumidifying/deodorizing properties of charcoal here.

The charcoal version is very simple: just put some charcoal in a container that has holes poked in the lid and place containers around areas that need dehumidifying.

The road salt version is a bit more obtrusive: you dump some road salt in cheesecloth, tie the cheesecloth off, hang it up somewhere, and put a bucket underneath for the moisture to drip into. No doubt Laura or anyone could incorporate this into home decor as ‘modern slaughterhouse’. “We wanted to create the homey illusion of slabs of raw meat hanging from the ceiling”. This is supposed to be very effective and gets rave reviews from the kind of people who know what ‘road salt’ is to begin with.

(Incidentally, someone mentioned putting the salt in a colander over a bucket — and he used a different kind of salt, rock salt I think — but he didn’t say how that worked out. However it’s a possible alternative to having to hang something.)

a long and fruitful conversation with the maintenance man

Our a/c maintenance man, who I like very much because he always compliments my housekeeping judging by how little dust is in our filters (this actually has far more to do with having wood floors and very few ‘dust traps’ as far as our furniture goes, but I am pleased to know that running a dust mop around irregularly is in God’s goodness, an effective means of dealing with this world’s dirt) came to repair a problem we had with our air conditioning last evening. After what felt like a thirty minute earthquake (mysterious in origin and explanation, as no one else seemed to experience it) our a/c started leaking water all over the floor yesterday. In the process of fixing this problem, whatever it was (my theory was a dislocated pipe from the extremely local but violent tremors) he explained to me the theory of air conditioning. I am a housewife of very unscientific brain, and I didn’t get it all. Nevertheless I found what I did understand extremely fascinating and quite useful.

1. At boiling point, water is both water and steam; and freezing point both water and ice. To overcome the surface tension of water at boiling point requires more energy than simply changing ice to steam (and vice versa). Somehow this ties into why the hardest thing the a/c is dealing with is not actually heat but humidity. (I found it incredibly wonderful as a mere fact, regardless of its relation to the a/c and humidity. Just imagine how much energy goes into raising water a tiny fraction of a degree next time you see steam coming out of your teapot. What a magnificent world, spinning in all this incredible strength that can just toss off enough steam for all the tea drinkers of the world daily. But I digress.)

2. Because of the humidity factor, and because your a/c is not simply cooling air which itself has very little ‘density’ (yes that is a word I quote verbatim) but is lowering the temperature of all the solid material in your home (including insulation), the a/c has to work much harder to effect a change in temperature than to keep temperature at a relatively stable degreeage (yes that is a word I just made up). It does *not* actually save you money to turn the a/c off during the day, to open windows (this lets in air that is of a different water saturation, not just a different temp), only to turn it on again when you get home in the evening and so on. The changing of temperature of solid material would also apply to a heater; and the water consideration would also apply, if I understand correctly, to at least some gas heaters (or heaters that use gas in some way — this part was a little beyond me: but water and steam are involved in there somewhere).

3. Not only does it make a great deal of work for the a/c, heat, and so on to wildly fluctuate the temp, without saving money — it can cause more mold than if you just always left the windows open, or always ran the heat/air. Because again, the heat/air are doing something with sudden large amounts of water when you suddenly kick them on.

The moral of the story is, that It would be better to turn the air or heat up or down in a not too drastic manner, and at least so far as the a/c is concerned, be careful about letting humidity into your home on a regular basis if you want to save $$ on the electricity bill.