Swamp cooler decision making

Just wondering if anyone had any opinions before I take the plunge.

My soon to be 'actual' greenhouse will be 8 x 16 x 8 with the roof going up to probably somwhere around 12-14'. When calculating the square footage to determine how much cooling I need I've been using ten or even twelve feet as the height. But it occurs to me that I won't need to be cooling anything above 8'.

So if I use 8' it comes out to 1024 square feet. If I use 10 or 12 it rapidly approaches 2000 square feet.

The coolers I've been looking at come in various sizes:
variable speed 16" fan with a 42 gallon reservoir and rated to cool 1000 sq. ft.;
variable speed 24" fan with 48 gallon reservoir and a cooling capacity of 2000 sq. ft;
and I recently found one that has a single speed 36" fan with 2500 sq. ft cooling capacity but only a 32 gallon reservoir.

Naturally to further complicate things the biggest one is actually the cheapest but has the smallest reservoir. And it is only one speed.

So I'm wondering if i get that one, will i regret not having variable speeds and a bigger reservoir? And if I get the smallest one, will it be pushing my luck being so close to the overall gh size for cooling capacity? I guess the obvious choice is the middle one which gives me the 48 gallon reservoir AND variable speed, but it is (naturally) around $300 (or more) more expensive.

Any input is appreciated.

 

Thank you already!

Here is a link to the medium sized one: http://www.port-a-cool.com/pacjs2400.html, it is rated at 7500 CFM.

And here is the (similar) smaller one which is rated at 4000 CFM: http://www.port-a-cool.com/pacjs1600.html

I believe they both have a hose connection although i'm unclear what keeps the water from causing problems from back pressure once the reservoir is full if the hose is on all the time. It will be situated outside the north wall with the outlet passing through the wall.

 

One main issue is i may not have a water connection. A plumber is supposed to come out tomorrow to evaluate the feasability of a dedicated water line. Problem is, the water line is at the front of the house and the greenhouse is at the back. There is no *good* way to get water to it. Whoever designed the infrastructure of my backyard was a complete moron.

The ones you both linked to are about a third the price so I would definitely prefer that over the pro-cool models. But the reservoirs could be a big help with the lack of water line issue. Like I said, that will get reevaluated tomorrow and could change. I suppose for the cost of the pro-cools, I could get a water line routed all the way around the house if needed.

And I wouldn't be too worried about the pro-cools not being permanent. Imagine them without the casters. Other than the radically different shape, there's no real difference. They're all just a fan, a tank, a pump, and a duct...right? I could cover it in the winter (and drain it of course), and shade it from direct sun. But...that aside, I do see what you're both saying. Of course the next problem would be finding one. I've already been to Home Depot and Lowes and they don't believe Oklahoma is dry enough to carry them. (we were at 10% humidity last week)

 

I have a feeling she's going to swing a shovel if I don't stop focusing on greenhouses while ignoring wedding plans!

I've always believed in the need for dedicated water. It's just so damn difficult due to the logistics. But you've all pretty much convinced me to save a thousand bucks by *not* getting one of those port-a-cool units, spend that money on getting the water line put in, and then go to Grainger for a evap cooler like the ones linked above. Home Depot allegedly can't get them in any store (which i find hard to believe). Sears might be an option but Grainger's website claims to have some appropriate models in stock so it looks like my best hope for the moment.

Anyone know anything about the brands Essick or Dayton?

 

Latest update: I will be assimilated, resistance is futile.

Apparently i can get a water line put in for less than $500 although it will have to be tied-in somewhere at the front of the house and a trench dug across the front, all the way down the side, into the back, and to the gh. But oh well, shouldn't be an issue.

So my next question is, what size is the water connection for swamp coolers? I just went to Grainger and looked at one. Naturally they didn't have the ones in stock like you guys linked to and like i want, but it was similar. The dude actually pulled it off the rack with a forklift and opened up the box. Then we took off some panels and I could see the pump and fan and the tubes that direct the water to the pads. But we could NOT find where the water actually connects to the &*(^%$ thing! He even called his technical support guy and he didn't know either. I have to assume that connection is standard on just about all models, no? Is it a half inch connection? Quarter inch? Full size hose? If anyone knows or if any of you have the actual type like Mfaar and Marni linked, it would be a huge help to know that.

And Ray, Grainger is pretty much my only hope due to time frames, logistics, and other factors. Home Depot claims they can't even get them shipped to their stores in the OKC metro. It could probably be shipped to my house but Grainger is only a couple miles away and the units I'm looking at are either $400 or around $600. So their prices don't seem too bad.

One last thing (yea right!), what about 2800 CFM vs. 3800? I definitely want to go bigger than 'needed'. Every day next week is supposed to be at least 108 degrees, for example, so I want to oversize it to some extent. But based on my gh size either one will actually be oversized. So my question is, would it be worth the extra 1-200 bucks to get the 3800, or is the 2800 plenty big enough?

again, thank you all soooo much for your help.