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Ideas for cooling down terrarium with water chiller?

Brie

Sarracenia freak
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So i'm going to have a spare 1/13th hp aquarium chiller free to use here in a bit, and I'm trying to think of a creative way to use it to cool down this terrarium/greenhouse i'm putting together. Any ideas? I was thinking maybe having a tray of water, like say a large kitty litter pan, or a plant water tray, full of water on the bottom of the terrarium and sending that water down through the chiller and back up again, keeping that water cold. Would this have much effect at all on the overall temp of the terrarium? Anyone have any other ideas that might work?
 
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pump the chilled liquid through an automotive heater core in the grow rack. (exaclty like your car heater/ac system)
 

Brie

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I know absolutely NOTHING about car parts or repair so I think that might be a little above me. I could probably do it if supplied with a walk through, but thats about it. Good suggestion though.

---------- Post added at 03:13 PM ---------- Previous post was at 03:12 PM ----------

Do you literally just set it inside the terrarium, hook up two hoses and bam, done?
 

Brie

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Ohhh I think I get it. Yeah, just run the cold water through the core, and have a 6" fan blow air through it. Hmm.. now how would you control that via thermostat I wonder? Hmmm... I also wouldn't want to run the chiller 24/7 to keep the core chilled, because it would kill the chiller in a fast way.

---------- Post added at 03:26 PM ---------- Previous post was at 03:22 PM ----------

Also, wouldn't it rust in the high humidity?
 
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there are thermostats on the market that seem to do well for this purpose

heater cores are usually brass... no rust
 

Brie

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Ok, I think i'll go that direction... It'll be about a 4ft long by 12-18" tall, 18" deep space(one shelf on a 4ft metal storage rack).

What would you hook up to the controller exactly? The chiller is thermostat controlled by itself, and turns on once the temp of the water reaches the temp in which you set for it to turn on, and there is a 2 degree differential. So I dunno if this would work or not. You'd wanna set a fairly cold temp, say 50 degrees, which would then drop the temp of the metal heater core, causing the air going past it to be cooled. But the chiller would not be happy staying on 24/7 to do this, and it would ultimately kick he bucket and stop working.

I suppose i'll see how hot the chamber gets once everything is set up and see if i'll even need to use it.
 

seedjar

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I've found that you can get substantial cooling even without a radiator - although I'm sure that would make the system much more effective. I've set up terraria with aquarium chillers using a makeshift radiator of coiled copper tubing or even plastic/rubber tubing (make sure to use opaque - preferably black) and they worked plenty well. Particularly if you use the potted-terrarium style and have a reservoir of water at the bottom.
I never got a chance to verify that it worked better, but the last one we did had a reservoir made from a small ice chest in the cooling loop; the chiller pumped into the terrarium, and then the water exiting the terrarium went into the ice chest and from there drained back into the chiller, the idea being that it would store some of the coolness even when the compressor wasn't running and help curb rapid temperature changes. It was a very nice chiller - built-in thermostat, ~4000 gph cirile capacity - so there was little need for improvement, but the compressor did seem to kick on less often when we added the cooler.
I want one bad. That monster could hold 100 gallons of water at 50 degrees in mid-summer... glad it wasn't my electric bill though. XD
Welcome to the forums BTW! (If I haven't already said.)
~Joe

PS - Re: controlling it, if your chiller saves it's set point when powered down, then the external thermostat could potentially help fine-tune the cooling process. Or you could use a closed loop on the chiller to cool the reservoir of a makeshift swamp cooler, for example, and then blow warm air from the lights into that to produce cool, humid air. You could also use the chiller loop to cool standing water in the bottom of the tank, and use something like an airstone or a small fountain pump to agitate and circulate the standing water, which would have a similar effect without requiring a wick and forced air. Being able to separately control the temperature of your cooling loop and the set point of the rest of your contraption should make it possible to reduce the strain on the chiller while giving you a say over how fast things cool down when it all comes on. By my understanding, the really nice thing about those ZooMed gadgets is that they allow you to have separate profiles for day and night temps/humidity (with day and night determined by a photosensor.) Swords recently set one up and wrote a nice thread on it - should be on the top page or two of the terrarium subforum.
 
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Much more effective...

http://www.trane.com/commercial/library/vol31_1/index.asp#dynamics

As the liquid travels through a tube you have regions of laminar and turbulent flow. The majority of heat transfer occurs at the narrow boundrary layer against the tube wall. This occurs both on the liquid side and the air side. (this is also evident when a cold glass of water causes condensation, start blowing air across the surface of the glass and the condensation decreases and the temp of the water warms up quicker)

To increase the efficiency we can increase the level of turbulent flow and surface areas both air side and liquid side. (we want to shy away from increasing velocities.... slower velocities over a greater surface area is much more efficient)

Typcial heat exchangers (aka radiators, heater cores etc) have cooling fins, flattened out liquid passages, turbulators, thin walls etc etc to accomplish this
 
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seedjar

Let's positive thinking!
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Oh I know about heat exchangers. Just when we were working on these designs before I had almost no budget and just my buddy's basement full of old reef tank gear. Thanks though, I'll take a look at that - is it in your list of academic bookmarks or do I need to set it aside for my own reference?
~Joe
 
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hehehe
gotta pic on ya my friend...your hunger for knowledge is unreal

wish i had a classroom full of ya, hmmm maybe LOL.... you would make it hard to stay ahead of ya

:hail:
 

seedjar

Let's positive thinking!
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My teachers simultaneously love and hate me. My poor comp sci professor who puts up with all my illnesses and incompletes just glares at me and shouts, "What do you want? Haven't you graduated yet!?" whenever she sees me these days. And my sensei often just rolls her eyes when I start asking questions. XD
~Joe
 
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This kind of applies to Ann's recent thread in a little more detail... mini fridges just dont have the heat exchanger capacity to effectively do what she wanted to do IMHO
 
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