evaporative air coolers?

Eeeww. Not that one. More hype than specs.

In what part of the country? Nearest city?

Nick

Where do you live and what's your climate? If you have humidity, evap's don't work. They are effective in dry climes (20% or less relative humidity). I can't comment on the cooler you linked. We've used evaps for years here in NM but our typical summers are quite dry (until the Monsoon season and then the coolers are pretty worthless). Cheers, cc

best advise is to visit someone else that has an evap cooler in your area and see if you like it.

if no one in your area has one, that tells you something...

Mark

http:/groups.google.com on evaporative swamp cooler will tell you more than you ever wanted to know.

Basically, if they don't sell them at the local bigbox hardware store, you can't use them.

Evap coolers are good for 10 to 15 degrees max and only work when the relative humidity is between 0-15%. Go any higher that and you risk creating a serious mold problem for yourself and they don't cool above that level of humidity anyway.

So unless you live in the desert SW, you shouldn't be using them. Even new construction in Phoenix avoids them because a) they use a lot of water, b) the grass and resorts have bumped up the local humidity, and c) going from 110 down to 100 doesn't buy you much on the comfort scale.

-- "Tell me what I should do, Annie." "Stay. Here. Forever." - Life On Mars

I used a Master Cool Plus located on a flat roof for 8 years in the Tucson, AZ area. Worked like a charm, did not need air conditioning except during the monsoon season, mid June to Sept approx. It used very, very little water and electricity; it just had to be disconnected in the winter to prevent freezing. Big 4x4 filter was hosed down once a year;, no mold, etc. In southern parts of New Mexico, they are in use for most of the year. Las Cruces comes to mind. The picture of the unit y'all supplied probably operates on the same principle, however I have no experience with it. I doubt if it would be effective above 15% humidity, as indicated above. hth

Itt is worth noting that afaict, the ad for that one says nothing about its effectiveness depending on where one lives. It says nothing about where the ones are located that they used to get the average 12 to 20 degree drop in temperature. They might be all in New Mexico, Nevada, and Death Valley. They sure don't work in Maryland. The URL looks dishonest to me.

I live in Phoenix, and coolers are fine through about June, but once the relative humidity exceeds 20% they become lousy. Here's a table showing the best temperature you can expect from a cooler, depending on the humidity and outdoor temperature:

Also coolers aren&#39;t necessarily cheaper to operate than newer air conditioners ( < 15 years old), and it was found that people who had combination cooler-A/C units spent more on cooling than did people who have only A/C.

Dave wrote: ...

A 16&#39;x16&#39;x8&#39; room with R20 insulation all round and a thermal conductance of 768ft^2/R20 = 38.4 Btu/h-F would only need Q = 10x38.4 = 384 Btu/h of net cooling to lower the room temp 10 F.

If it&#39;s Ta (F) outdoors with a wa humidity ratio and 80 F indoors with wi = 0.012 pounds of water per pound of dry air (an efficient corner of the ASHRAE comfort zone), evaporating P lb/h of water while ventilating with C cfm of 0.075 lb/ft^3 outdoor air makes P = 60C0.075(0.012-wa) and

Fresh air might come from 2 vents with an 8&#39; height difference. If 31 cfm = 16.6Asqrt(8&#39;x(87.1-80)) (an empirical chimney formula), A = 0.25 ft^2, eg 6"x6" vents. Outdoor air with Pa = 29.921/(1+0.62198/wa) = 0.366"Hg, and Pw = 0.566"Hg indoors and 0.61 = 0.1A(Pw-Pa) (an ASHRAE pool formula) makes A = 30 ft^2, eg an 8&#39;x8" diameter 2-sided porous shower curtain below the upper vent with a 10 watt fountain pump moving 1 gpm from a sump with a float valve up over the curtain whenever the room temp rises to 80 F.

Or maybe a 5&#39; tall x 8" diameter nuclear bong cooler (see wiki :-)

water temp (F) air temp (F)

21850.99 Btu/h

Nick

I&#39;m in Cincinnati, which can get pretty humid during the summer. But, I have central A/C. I&#39;m just looking to cool an upper floor bedroom by about ten more degrees. I&#39;m hoping the central A/C has dropped the humidity enough to make the air cooler effective.

Thanks Nick. It&#39;s a long time since I&#39;ve seen a BASIC program listing. I shouldn&#39;t have thrown out that Commodore VIC-20.

;-)

"Q. How effective is the evaporative cooling? A. On the average, the CoolAir 4000 can lower the temperature

From the ad page. Read with attention to detail, they hide the details.

Even with central AC, I really doubt that evaporative mister thing is going to do much good. I&#39;d suggest looking at air flow from the central AC, or get a window AC.

Thank you. I missed that and it&#39;s in print the same size as the other questions.

Of course it is artfully phrased. "Best when ...below 50%". Apparently it does really really best when it is below 16 percent, but we won&#39;t discuss the area between 16 and 49! Why not say "Works best when.... below 90%"

I get confused when things get too complicated, but lets assume the AC could make the humidity in the house 15% or less. But then this swamp cooler would cool the temp further by adding humidity, which would get down to the first floor** within a day or less, and which the AC would have to work to remove.

Wouldn&#39;t this be just as bad as making spaghetti or taking a hot steamy shower in a house with AC? Don&#39;t people avoid those things? Because they add substantial costs to running the AC?

Naw, too humid. Here in the Denver area they work pretty good. Even usable when the humidity gets up to 30% as long as they are moving a lot of air. Outside temp above 90 and the air coming in will be in the low 70s. When our temperatures get near 100 the humidity may be below 10%. And here it always gets cool enough at night that only a fan is needed.

I saw this ... I believe that with my central A/C, the room humidity is less than 50%, so I was hoping ...

We had someone look at the air flow situation once, and from the work he said would be necessary to improve things, it sounded like it would be very expensive.

Regarding a window AC unit, I bet the other husbands out there will understand this: my wife doesn&#39;t like them because she thinks they&#39;re ugly. ;-)

(But after reading these posts about air coolers, I think I&#39;m going to make more of an effort to change her mind.)

Thanks all .....

I live in Las Vegas, Nevada, and can give you some first hand information. Before refrigeration, all we had was swamp coolers. It was better than being outside in the heat, and at night, temperatures were good for sleeping. That said, they have lots of limitations. When it&#39;s really hot, they will cool things down, but not like refrigeration. When it&#39;s humid, they hardly feel like they work at all. They put so much humidity in the air that after a time, the house smells like one in South Louisiana. Damp and musty.

We still use swampers for a few months a year. Mostly in the spring and fall when we only want to drop the temps a little. Nothing works very well in 115 degree heat. Even a 20 degree drop leaves you at 95 inside. And swampers do not work well at all in humid weather, as we are having now in Vegas during our monsoon season. 40-60% humidity ranges.

Swampers help. But, I think that they do the best for the people who sell them, and claim that they will do all sorts of things they won&#39;t. And since the principle they work on is temperature difference created by water evaporation, some of the claims made in humid areas are laughable. Even if you get one, and it works, it won&#39;t work all the time.

Steve.

It isn&#39;t going to stay below 50% once you start using the evap cooler then.

I have a llittle experience with swamp coolers in Las Vegas, also.

My friend from San Diego said he could win at Blackjack, by playing a system. I started studying the system, but then he wanted to leave Chicago a week early and I had barely gotten started trying to memorize it. Three of us drove all day and night and got to Las Vegas in the middle of the night.

We stayed in one room at the hotel of his choice the next day.

Then they laft (the third guy was another college friend of Dick&#39;s , going to visit him in San Diego.

Since I was there to make money, and not to spend it, I went looking for a cheap hotel. There was supposed to be one with AC, but I didn&#39;t know where.

I found one with air cooling, and I figured that would be fine because as everone knew, it gets cold in the desert at night. During the day I figured I would be at the casino.

I think I paid for a week. I know I was in LV for 7 or 8 days and left on July 5.

Boy, was it hot at night. The cooler was in the hall, only 3 feet from my room&#39;s door, which I left open, but the fan was blowing down the hall and my door was at a right angle. It might have been cool in the hall, but it wasn&#39;t in my room. (The hotel was built as a large house iirc.)

By the second or third night, I was sleeping in the back yard. Unfortunately, the yard had no grass, only gravel. I sleep on my belly so I put a towel under my face but it really wasn&#39;t comfortable.

Because I never got a good nights sleep, I wasn&#39;t able to memorize the

I did go to the fireworks July 4, in a residential n&#39;hood. On the way to the fireworks I walked past a public school and though seriously about sleeping on the grass there. I don&#39;t remember why I didn&#39;t. I guess I still worried too much about the police in those days. Within a couple years, or days, I realized they would never do anything to me for just sleeping.

Earlier I went on the tour of the Mint Casino, where they explain how to play craps, and show you a bit of how they watch from above the ceiling. I asked this guy if he was in the line for the tour, and he was, and we went on the tour together, and then to a drawing he was entered in across the street, and then he invited me to come out to dinner later in the week. He had his own simple apartment on the strip, behind the Flamingo Casino, and we met at the pool there. He took me out to dinner on one of those all you can eat coupons at another casino. During dinner he told me I was a great conversationalist. After dinner he propositioned me. He offered me free room and board and offered to rent a car that I could use to drive him around, or just myself the other half of the time. When I didn&#39;t bite, he offerred me an allowance, and to pay off the 40 dollars I had lost. (Of course I&#39;d already paid it, but I guess he meant he would give me 40 dollars.)

I asked "What would this entail?" and although his answer wasn&#39;t vulgar by Jay Leno&#39;s current standards, it&#39;s too vulgar for me to write.

But now it was 11PM and the big dinner made me sleepy, and I had made the mistake of leaving my swimming suit in his apartment. (My cheap hotel had no swimming pool, and I was too law abiding in those days to swim in the Mint&#39;s rooftop pool, where they did check room numbers it seemed. I was hoping to swim in the Flamingo pool, where I think they knew him, but certainly I could have in his apartment pool.

So walking the 200 yards back to his apartment, I asked if I could stay there no strings attached. He said yes. He said I should sleep in his bed, but I said the couch would be fine. He said that it would be better for me to sleep in his bed because then he would know that I was on guard and he would be especially careful not to do anything I wouldn&#39;t like. I&#39;m very smart, 1540 on the SATs, but consistently slow-witted, and as ridiculous as this last remark was, I didn&#39;t notice.

So he gave me a sheet and maybe a blanket and I went to sleep on the sofa, on my back as I do when I have to wake up soon. Not sure when, maybe 30 or 60 minutes later, I wake up to the feel of someone tickling me through my underpants. "What an idiot, I am" I thought to myself, without moving a bit or saying a word. "We&#39;re going to have a confrontation. He&#39;s going to be embarrassed, and he&#39;s going to kill me.** So what should I do?"

I just sat up without saying anything. He was kneeling on the floor by the sofa and he backed up as fast as he could, ending in a cheap padded chair with arms that was part of his living furniture, but only

But I still didn&#39;t preclude the notion that he would get tired being scared and turn into the aggreessor again. Once I don&#39;t trust someone, I don&#39;t trust anything about him. I had had girls stay at my apartment, and when the agreement, spoken or not, was that I wouldn&#39;t touch her, I didn&#39;t. How hard is that?

But this guy&#39;s story was funny. He said he thought I might be cold (because of the AC) and he was trying to wake me to ask if I wanted a blanket, or a second blanket. Even slow-witted me knew that was a lie. And even if I were cold, I&#39;d rather stay asleep cold than have to wake up to get a blanket.

In order to avoid a confrontation, I told him I was going back to sleep and after he went to his room, I went to the bathroom and got dressed, flushing the toilet so he wouldn&#39;t hear my belt jingling on the tile.

I had his number and I should have called him to tell him how lucky he was that I didn&#39;t beat him up. It took far far more to get me angry in the old days, at least to get me angry for more than 5 minutes. He did deserved to be beat up, so he wouldn&#39;t lie to someone else.

Oh yeah, one of the reasons I was willing to stay there was to finally get a good nights sleep, so I could finally memorize those tables and win at blackjack. But again I didn&#39;t get a good night&#39;s sleep. I was doubly stupid if I didn&#39;t get 9 hours of sleep each night. I think I was leaving the next morning, and only had a couple more hours to gamble then.

Maybe tomorrow I will tell you how I got back to Chicago.