Nice setup! If I ever get my cooling system started I'll use an aquarium chiller. Also, your terrarium's background is great, I currently only have mirrors all around :/
Oh, the humanity!!
Thanks again y'all!
@robthered: I'll definitely keep you posted on temperature drops. I just reset my digital thermo/hygro because the recorded low was 55 degrees... not sure whether that was from last night or some random evening over the past year I've had it! I will say that I was slightly disappointed to find that an hour after the lights had gone off, the temperature was only down to 65 degrees. But who knows, maybe it got down farther overnight. I ended up using cold-weather windshield wiper fluid... I made sure it didn't bubble when I shook it first, though! Although I'm not sure if the antifreeze is even necessary. Pretty sure this cooler can't chill water down to freezing!
@pmatil, thanks! Yeah, that's the background that came with the terrarium. It's just a cheap piece of styrofoam. I debated chucking it out because it does take up space that could otherwise be used for plants... but for now I kinda like the look.
With the coming warm temperatures here in Brooklyn it's gonna get harder and harder to get the temps into the 50s and 60s. Right now I am using my Ac to cool my setup since we now have days of 90 degrees. You could try investing in one of those swamp coolers but I don't know how effective they would be in the humid Brooklyn summer. BTW, that's a nice Heli you have, what type is it?
Oh, the humanity!!
Yeah, we'll see about that. Not to say I'm worried -- worst case, I'll have to stick to intermediate plants (of which most of my Neps are anyways) and not HL Neps. I'm OK with that; most of my favorite Neps don't require true HL conditions, just moderate daytime temps and a decent nighttime temperature drop. As long as I can keep temps below 83 degrees or so on the hottest summer days (when temps in my room exceed 90) I'll be a happy camper; with ambient temps in the high 70s and low 80s my cooler seems to have no trouble keeping temps inside the terrarium near or below 70.
I actually bought a swamp cooler and returned it promptly about a year ago. It's just too humid in the northeast for those things to work. When I had one, it cooled the room down by about three degrees until the air in the room became saturated with moisture, then the cooling effect stopped and the temps rose again... only this time, it was really uncomfortable in the room with all that heat and moisture! It only really works when there's plenty of capacity in the air to continue to evaporate liquid water (which is what causes the temperature drop).
And that's a H. heterodoxa x minor. I got it as an unrooted division and it took hold pretty readily, though the pitchers are short and there are no nectar spoons. Hopefully the temps and humidity in my new terrarium will fix that lickety split.
Very cool, i love to see all the cool inovations come together
Oh, the humanity!!
Thanks for the comments I worked on this for so long yesterday that I think I tired myself out. I just came down with a cold! D'oh!
Also, @pmatil, I considered throwing down on an aquarium chiller but considering the money I was spending on lights, supplies, and the terrarium itself, I thought it best to hold off and try something cheaper. It'll be easy to switch this water cooler out with an aquarium chiller later if need be. But yeah, considering the cost and the power draw (my lease limits me to one 6,000 BTU AC unit; an aquarium chiller is nearly as powerful) I thought it best to explore other options first.
If anyone ends up going the aquarium chiller route, though, I want to see the results!
Never Knows Best
Oh man this is a great setup !!!! I absolutely love it!! And I gotta admit it is nice to have other people work out the kinks before I get to build it heheh!
Now onto the questions:
-Did you go with the peltier based (thermoelectric) cooler or a typical compressor based one?
-Also a little warning. Although I thought that it would be pretty rare I discovered that my windshield-washer fluid has methanol in it as anti-freezing agent. I was thinking it'd be some glycol instead. If such solution is kept open, MeOH will evaporate and that is not a good thing to breath in.
-I was also wondering why you have used the copper tube on the pump output. Is it to try and cool down the warmer returning water, that the pump will tend to draw in since it is positioned near the return hole?
-Also, why not put the radiator inside the terrarium so that it cools the air within more efficiently and not draws warmer air from outside?
Thank you in advance for answers! And again, very cool and impressive!
Oh, the humanity!!
@all - I just checked my thermo/hygro and it looks like temps dropped to just below 61 degrees last night. That was with an ambient room temperature of 73. So, not too shabby! I can't grow ultra highlanders in there or anything but as long as I can maintain a 10-degree temperature drop at night and a solid 10 degrees below ambient temperature (meaning low-80s at most during summer heat waves) I should be golden!! Most of my plants are intermediates or tolerant HLers, so I'm not too concerned.
Hey gill_za! Thanks for the kind words. Coming from you, they mean a lot--what with your aerospace engineering skills crafting a grow rack into something I could only *aspire* to build (but not actually execute on... a fact to which the state of my previous setup and plants toward the end could testify).
Seriously though, you must be an engineering student right?
Anyway, glad that I can vet these designs for other folks to try & improve upon!
Now the answers to your questions:
1) Nah, I didn't go with the peltier device. Av & co convinced me once and for all that if you're trying to cool more than a six pack of beer, you're better suited going with a good old fashioned power-hungry compressor. I have a countertop water cooler that's compressor-powered. It's a pretty good find... it's compact but seems to be just as powerful as the taller, free-standing models. Got it for $50... my first Craigslist purchase!
2) Methanol? Crap. I know the ingredients on the bottle said some form of alcohol was used as the antifreeze agent, but I don't recall whether it was specifically methanol. If so... how dangerous are the fumes we're talking about, given how much the solution has been diluted? I certainly don't notice a chemical odor in the air...
3) I used the copper tubing exactly for the reason you guessed. The return from the radiator spits out right at the base of the pump, so to make sure the fluid is as cool as possible before it gets sent to the radiator, I put it through 10 feet of copper tubing to pick up the chill from around the stainless steel walls of the reservoir before it hits the output that feeds the radiator.
4) That.... is a good question. Never thought about it, to be honest! I guess the radiator is pretty bulky and would take up valuable plant space. Were it your setup, how would you position the radiator? Lemme know and I'll try it out!
Never Knows Best
OMG, TheFury what an overestimation of my poor skills. My growrack is shabby. And every other idea (including growrack) was inspired by you and other people. LOL But thank you for kind words.
With methanol, you should be ok in a WELL ventilated room. I work with methanol in the lab and I honestly can't smell it very well, to me it has a very faint odor, but others smell it well. So, I don't know if you can tell by smell alone if you are building up vapors of that stuff in the room. Besides the volume of your coolant is pretty low to. But, it will evaporate even if cooled, its melting point is -97C and boiling 65C. So, not to alarm you or anything, but keep it in mind. Skin or eye irritation could be signs of vapors present in the room.
The other issue is that this mixture might catch on fire if it is concentrated enough. Methanol is extremely flammable. So be careful. I'd dump it completely if I were you and replace with water. As you mentioned yourself it does not get cold enough to freeze.
One potential problem with having the radiator inside as others mentioned will be dehumidification of air in the terrarium. But if you are running the humidifier constantly it should not be a problem. Humidity, could damage the fans if they are in a very wet air. But if you leave the radiator somewhere closer to the top I'd think it would solve the problem.
I am sure others with more experience and knowledge can point out other issues with this approach. But the potential benefit is that your cooling will be faster and more efficient as you will not be cooling hot air from outside and you could reach lower temperatures.
Keep in mind I haven't even built this thing yet myself, it's just something that I suspect I myself will run into when building it. And I'm learning quite a lot from your thread and robthered's.
I've just today contacted someone from craigslist about a water cooler
And what is interesting is that I've done a quick search on google and haven't yet found similar setups with water coolers. So robthered's idea might be unique He should post it on "instructables" or something.
Thank you for the thread, very informative!
Originally Posted by TheFury