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Hey i got a 18"x 18" refrigerator

superimposedhope

Somewhat Unstable
Hey guys, I got a small 18" X 18" refrigerator tonight that is all moldy and YUCK!!!

Sooo, I was thinking, could I pull the cooling unit out of the back and use it for a highland chamber? It does cool to about 40deg.F. after like a half hour and that was sitting out side in the heat.
Would it be worth it?

Let me know
Joe
 
The thing is finding a way to seal and insulate the enclosure so the cold doesn't escape. Also, Airconditioners and refrigerators pull the humidity out of the air so you need to find a way to replace that. Maybe an ultrasonic humidifier, fan and humidistat to keep it regulated.

I have thought of the same thing (using old fridge parts to bulid a really big chamber) but I don't know how you would rig the sealing & insualting part. I'm sure the pink foam insulation sheets from home depot would be OK but sealing it.
Maybe build a frame with 2 x 2 lumber and using two sheets of waterproof tub surround sandwich the pink foam sheetsbetween the tub surround.Then seal all seams inside and out of each wall with silicone or tub caulk. Then place the cooling unit centered in the rear behind your chamber with the cooling rods running up & down the back.

I'm not 100% sure this would work mind you, just another of my hairbrained ideas!

If you build a big tank, I'd use a storm window for the access since they have weather stripping and are more or less "airtight" compared to a plain sheet of plexiglass or even a sliding shower door. I've used all 3 and the storm window kicks - - - ! if you buy the "single pane" ones they are cheap! The one on my current HL tank is 48" L x 36" W and was only $26.99 new at menards! This window likely wouldn't actually withstand any real storms (!!!) but it's perfect for an indoor terrarium, light, and airtight!
 
I'm not exactly an expert on grow chambers, but I have looked into the possibility of building one just for a handful of highlanders to use for hybridizing. I think a refrigerator is better than an air conditioner in terms of cooling with high humidity. I spoke with an AC engineer who installs both commercial AC units and walk-in coolers for restaurants and he recommended using a refrigerator, not an AC, because the AC removes humidity and the 'fridge does not as much. He also informed me that it is cheaper to run the refrigeration unit than the AC, which would eventually be damaged by the high humidity. The trick is sizing the fridge to the space that must be cooled.
FWIW,
Trent
 
Interesting, so Trent, are you saying that over a period of time that an AC unit will be damaged by purposely adding humidity? It makes sense I suppose since they do remove it.

Josh, perhaps you have posted this befor and I missed it but, what exactly is your highland chamber made from (hum., cooling, etc...)?

Thanks
Joe
 
That's what I was told. AC's are designed to remove humidity from the air. High humidity makes them work harder, thus "wearing them out" as he said. Also, it's very energy inefficient.
It may be a different situation if the AC intake is not from your grow chamber. The thermostat would then be run out to the far side of the grow chamber to assure proper low temps are being reached. I would do the same thing with the refrigerator.

Trent
 
Here is the diagram of my setup using an air conditioner.
coolingdiagram.jpg


Key:
A) Intake fan -set in window if cool outside or hang on front of air conditioner during hot weather
B) Mount for fan and air duct
C) Flexible air duct
D) Ultrasonic humidifier
E) Hose from humidifier to incoming air duct, not terrraium
F) Grow chamber

The air conditioner itself is not located within the humid, highland environment but is outside the chamber before the intake fan (A). You do not want unadultered AC air going into your chamber because it is cold and dry. Lids on many plants will close overnight - I know from my very first night W/ highlanders! The way it is set up here, the incoming cooled air is saturated with humidity before it ever reaches the plants and you get both cold and humid air. If you want to put a greenhouse thermostat in the grow chamber to control the AC you can but I don't bother anymore. I think the plants appreciate the more natural few degrees warmer today few degrees colder tomorrow, more like a real greenhouse or "nature".

As far as the humidity affecting the AC unit itself, the humidity never reaches it the way it's setup. In 3 summers of doing it this way the most harmful thing for the AC is me loosing the removeable air filter and the unit becoming clogged with dust and debris!
smile.gif


If anyone has diagrams or info on setting up a fridge cooled one I'd like to study it.
 
Hm, this might be a odd question, is it feasible for you to put an ultrasonic humidifier IN your fridge, drill a large hole in the door of the fridge, and use a tube to transfer the humidified air to your growchamber?
smile_k_ani_32.gif
 
It would depend on the size of the hole. Why not remove the door (on the 18" x 18")and build the chamber extending off the fridge. Remove the thermostat and place it on the far side of the chamber and set for desired low, place humidifiers inside the fridge with a small muffin fan to provide air movement. If the fridge is elevated from the floor of the chamber, cold air could flow down and around the plants. Between the daytime highs-when the lights are on, and the night time lows-when the lights are off, something workable should be fairly easy to achieve.
I think you've got something very workable, Joe.
Josh's set-up works great too, I mean, look at his results!

Trent
 
Theres no arguing with Josh's results thats for sure. Beautiful plants Josh!
I think I may have something here. I was thinking something along the lines of Trent's comment, about extending off the front of the fridge use maybe a small comp. fan and humidifier. I know humidity will stay in a fridge and just frost or sweat on things. I am gonna ponder on this a bit more.

Keep the ideas and what-not comming, you have already been very helpful
Joe
 
  • #10
Well yeah, you could built a little funnel tray inside the fridge too, so even if the extra moisture sweats everywhere, it'll run right back down into your ultrasonic humidifier tray.

Hey, cold air rises, you could also put the fridge UNDER your growchamber. Dang, that would look wicked cool with the humidity flowing up. Or, put it on top - mount growlights to the parts facing down - and use a fan to blow it into the chamber.(heh, the few years I studied environmental resources engineering is coming in handy)
 
  • #11
Uh, cold air sinks, hot air rises. Those big beautiful balloons I see drifting over my house on Saturday morning are going up because of hot air, not cold air.
If the open end of the fridge is in the upper part of the chamber, the cold air being produced will flow downward into the main part of the chamber. No doubt there will be some stratification, but fans could fix that.

Trent
 
  • #12
Wow, that's what I meant. I promise I'm not that stupid on a normal day
smile_m_32.gif
. But anyway, wherever you place the fridge, fans could help regulate the flow and mix the humidity in as suggested. It'll be interesting figuring out where to put the lights (in, out, on the bottom of the fridge?) since it'll also change the temperature and flow of air. I'm also now wondering - are there fans to cool the fridge's motor anywhere? I'm wondering if that could be utilized instead of adding a fan.
 
  • #13
WickedT, cold air falls (low pressure), hot air rises (high pressure)!
smile_m_32.gif


Ah, I should've added that the air inlet for my setup is in the top rear left corner so the cold air blows in diagonally towards the top far right corner and descends over the plants. I don't have any condensation at all even with the humidity regulated to stay very high. It is likely due to air movement. In such a small chamber even a small fan will create quite a draft. At one time I had an extra pair of small oscillating fans in the chamber plugged into a reef wave timer as an experiment with cross breezes and alternating winds but there was so much air movement that the humidity wouldn't stay high enough.
(Incidentally I'll be ebaying a reef wave timer soon!
smile_n_32.gif
)
 
  • #14
Hi Joe, Josh and Trent

I'm not one active member of the forum since I don't have so much time to answer lots of messages, however the issue discussed by you - how to make one cold chamber to grow CPs - interest me so much. In fact I'm hunting heads interested on this topic to make part of one discussion group specially dedicated to it on Yahoo groups called terrariumcontroll group where I'm the moderator. By the title you can have some idea about how we are planning. The discussion group is not completelly free, the subscription is under approval just to limit the mumber of members and to choose the people really interested on the project and if possible having some knowledge on the areas involved to make it. As one little appetizer I can say that we are planning use Peltier Cells (or TEC - Thermo Electric Coolers) as cooling/warmer devices and microcontrollers.
By last, my thanks to Michelle for inform me about your discussion on the forum.

Best regards,

João Roberto
 
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