Ice Powered Cab Cooler!

[sunnydog]

Here is a diagranm for my ice powered cab cooler.
Keeps cab cool without losing co2, ALSO, VERY QUIET!!
Also, de- humidifies!!
Built one many years ago.
Kept a cab with a 400 (no cool tubes, they were not invented yet!!) perfect on about 4-6 frozen 2 liter bottles a day!
Now, I would use a cool tube to remove the primary heat FIRST(separate blower)!!
I think I will be making one of these again.
Gonna convert my cab to a 2x400 verticle grow with co2.
I will try to do a tutorial to fill in most details.
SD

 

[stke_fingas]

nice! it may look wild drawn up, but the real working version would be simple and very small. this would work in a cab too if you had the room and isolated the "heater core" kinda how its installed in your car. i have been thinking of this idea of heat exchange for a long time for keeping res temps in check. never had the balls to implement it.
you rock!
2x400w in a cab, and vertical!? dude... that is what i'm talking bout! i'm going to make the same thing. been thinking about it since i built this one. gotta go CMH and no temp problem's at all. bla bla bla

check out my cab!!! it's a little different than what people are use to but it's starting to have some followers already! and right up the same alley, v-scrog is the way to go for sure! the net is a must when doing vertical IMO. makes everything so much easier.
day 20

 

[sunnydog]

Thanks.
I will also put a carbon scrubber inline on the cool, dry return flow side.
How does you cab yield?
I'm thinking about putting shelves in mine.

 

[sunnydog]

Cool idea.. a basic mini-split A/C
Why don't you just put the cooling core into the cab and run a fan over it, rather then ducting it out and then back in?

It condenses A-Lot of water (de-humidifies) thats why you need the tub with a drain.

 

[FullMetalJacket]

So you periodically have to replace 2 liters eveyday? What if you leave town for a few days? Seem large too if you use more than 1-2 2 liters in the ice water piece. I would think that would be way too cumbersome to maintain.

I was thinking of something using one or 2 of these as a cooling option some how...i mean they do use these to cool wine coolers, mini fridges etc...

http://cgi.ebay.com/Huge-Swedish-ThermoElectric-Peltier-w-Heatsink-Fan_W0QQitemZ200227612216QQihZ010QQcategoryZ42910QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

You may not even need a cooling device based on your cab size. I run 600 hps in a 30 cu ft cab that doesnt go over 90 as long as I cool the light. The ambient room temps must be kept at or below 72 for me to accomplish this.

As long as your heater core is is sealed, you will not be adding additional humidty into the cab as someone stated you would, you would be removing it. Obviusly you know this though as you have done it and have a drain in there.

 

[hoosierdaddy]

FMJ, the peltier units you show may chill the water, after a good bit of engineering and DIY. You also need to contend with the heat from both the unit and the 6amp DC power supply something like that requires. The power supply itself will create a good deal of heat, and they are for sure not cheap at 6amps.

What he is showing is a poor mans approach to a very simple concept, and will work fine.
And the heater core being sealed has nothing to do with the creation of humidity. The H2O is in the air, and when warm air is cooled, it loses 50% of it's water holding ability for every 20degF drop in temp. This means that the air will almost instantaneously spit out the water it's holding as it passes over the cooling fins. The spitting of H2O will result in condensation as the water turns from vapor to liquid. If this liquid is not removed via a duct or pipe of some sort, then it will eventually become reintrained into the atmosphere by changing back to vapor through evaporation. The atmosphere in this case is inside the cab. So without proper drainage, you are essentially increasing the humidity levels in the cab by introducing more water in the form of liquid, whereas before it would pass through being held onto by the warmer air.

 

[FullMetalJacket]

FMJ, the peltier units you show may chill the water, after a good bit of engineering and DIY. You also need to contend with the heat from both the unit and the 6amp DC power supply something like that requires. The power supply itself will create a good deal of heat, and they are for sure not cheap at 6amps.

What he is showing is a poor mans approach to a very simple concept, and will work fine.
And the heater core being sealed has nothing to do with the creation of humidity. The H2O is in the air, and when warm air is cooled, it loses 50% of it's water holding ability for every 20degF drop in temp. This means that the air will almost instantaneously spit out the water it's holding as it passes over the cooling fins. The spitting of H2O will result in condensation as the water turns from vapor to liquid. If this liquid is not removed via a duct or pipe of some sort, then it will eventually become reintrained into the atmosphere by changing back to vapor through evaporation. The atmosphere in this case is inside the cab. So without proper drainage, you are essentially increasing the humidity levels in the cab by introducing more water in the form of liquid, where as before it would pass through being held onto by the warmer air.

hoosierdaddy, thanks for you expert explaination sir...

I am very aware how humidity works. Based on the illustartion i thought this unit was situated outside the cab. The reason i said heating core being sealed is the additional humidity taken out of the room this "external device is in" especially if the air is warm. You would be passing the air through a moist enviroment. I am aware of why you need the drain, but you can never add more moisture back to the unit via evaporization than you are removing as the H20 is just not there.. unless of course the area housing the heat exchanger is not sealed and you are alos condensating the external air...

I purchased that peltier unit on ebay. The auction i chose has two of them and a power supply for them both for $150. I would not use them to cool the "water heat exchanger" as in this design. I am just placing the cold side that already includes a fan inside the box and the warm side external to the cab withe a fan externally removing the heat from the heat sinks.

Do you really think that water bottles cooling the water that cools the "heat exchanger" will really lower the heat exchanger temp enough that you would get good results when you try blowing air over it to cool it? Even if you used 10 2 liters i don not feel they would cool it enough. Especially after an hour or two when the outer layer of the 2 liter melts and a "layer of water" acting as insulation in the 2 liter exists. I feel you need some type of compressor or Pelieter device to accomplish this based on the design in the diagram provided. I doubt you will lower the air temp by more than 2 degree with this approach or even at all depnding on the heat generated by the fan and water pump.

Maybe it would work if you used like ice cubes or crushed ice to increase the surface are over 2 liters and eliminate the "insulating water". Then you have to empty water when ever you add ice.

Im not trying to bust balls just giving people something to think about so they don't waste their time. Maybe i am wrong but this is what the board is all about. Discussing aproaches and their validity so we all learn. Worst case scenrio, i make someone think about having to place 2 liters in a res once a day. Regardless, best of luck and let me know how it works out foranyone that attempts this...lol


________________________________________
Hoosier, Here is how im setting the thermoelctric device up as i didnt want to explain it above I posted this on another board.

ThermoElectic Devices:

In laymans terms, thermoelectric devices are basically a small plate that exchanges heat from one side to the other. Most often each side of the plate has heat sinks, one that gets cold and one that gets hot. They use these in small dehumidfiers, some mini-fridges, high end computers, wine coolers etc. These devices are not the most effecient and are less effecient than a compressor commonly found in AC units.
To make these devices as effecient as possible you need to dissipate the heat from the hot side. Fans can be used to do this. The cooler you get the hot side the colder the cold side will get. These devices are cheap, silent(except for a fan to cool hot side), and available in different sizes or wattages. They are also neat because if you change the flow of the current the hot and cold side changes. They are easily controlled with a volage regulator to get precise temps. So accuarte that they are the choice in labratory and scietific research settings for cold plates and cooling/heating chambers.
For more detailed info on what a thermoelectic effect is visit:
Thermoelectric effect - Wikipedia, the free encyclopedia
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First, the reason I am looking into this technology for cooling and dehumidifying needs is because I want a fully contained cab with complete enviromental control. I have a 36 cu ft flower chamber and a 5000 btu airconditioner and 20 liter dehumidifier are overkill(smallest devices i could find that were quality). They are also loud, very large, expensive, draw a lot of power, and would require a fair amount of work to vent properly while keeping them in the cab. If you refer back to my drawings in my first post you can see how i would se-up my cab if i did use these large items. I would loose stealth though because of the size and noise. The swamp collers add too much humidity and the dry ice DIY cooling chests that fittz9723 posted looked promising but after the many posts about them not working well, i dont consider it a sloution. Plus you have to keep the ice fresh which i would just rather not grow then worry about that..lol

My temps are fine without venting the air in the cab at all due to the cooltube. Temps max at about 91 (with CO2 this is fine) with my cooltube fan running at 75% speed. But my humidity will most likely be an issue. I like my hudidity around 40% or below for flower, especially late flower. Since I live in an area where ambient relative humidity levels are very low, simply exhanging my air hourly would definitely lower my humidity levels into the desire range. But as I stated earlier I would like to have complete control over the enviroment in the cab. Less ventalation equals less noise, odor issues(even though im carbon scrubbing), and CO2 waste. Plus its cool as hell and make the cab usable for scientific research on growing.
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I would build my own device with parts all found on ebay and I am thinking around $150 total. The challenge is getting the right size/wattage. The cold side would be in the flower chamber and the hot side would be in my utility area. That is very important because like AC the devices in their entirety generate more heat than cold.
I have purchased a 26 watt EVA-DRY dehumidifier that uses this technology and is like 6"L x5"D x"8H. It is 26 watts including the fan and removes approximately 10-14oz of water over a 24 hour peiod according to the manufacturer. I do not think 10 oz in 24 hours is enough but if someone disagrees, please do share. Another problem with it is that it so slightly raise the temps as the air comes in, hits the cold side air sink(removing the humidity) and then passes over the hot side heat sink. Each air sink is approx 2" square inches.


I was thinking going 100W with 1 7" x 4" heat sink on the cold side and one 9"x 5" heat sink on the hot side. If I do a good job of cooling the hot side air sink I would definitely think I could remove 80-100 oz of water in 24 hours. I would think this would be more than enough. Well I stated i would only have the cold side in the flower chamber, i would have a smaller 4"x4" hot side in the chamber to reheat the air after i dehumidified it. This would also enable me to control the heat of the smaller one to use it as a heater, or cut power to it and use the dehumidifier as an "AC" device. All of this wouldn't take up any more space, just the regulation of diiffernt wattages to the TEC(the transfer plate).
I found a few alraedy constructed devices on ebay that can be modified and have more specefic heat measurements if you want to look at them, they are vey informative on how they work as well.

search ebay for "thermoelectric" or...

Huge Swedish ThermoElectric Peltier w/ Heatsink & Fan! - eBay (item 190224036970 end time May-28-08 10:31:40 PDT)

Another device from electronic supplier:
http://www.allelectronics.com/cgi-bi...C_DEVICE_.html


I am not sure these in the above links are large enough to meet my needs but might be. Maybe i can use a few of them. I think making my own would better suit my needs, be more effecient, and save money.
I may not need any additional AC or dehudification at all in my cab but i think building one of these and getting some accurate real world test results in a grow cab would benefit others.
____________________________________________________________

 

[Hawk]

FMJ, can't wait to hear how the thermoelectric cooling works out. I recently saw a used Coleman cooler with thermoelectric cooling and considered getting it (only $20) just to play around with the guts of it.

 

[Anonymous7o2]

so how would you hook up one of those thermoelectric coolers to a cab? does it need anything special for it to keep things cool?

 

[FullMetalJacket]

so how would you hook up one of those thermoelectric coolers to a cab? does it need anything special for it to keep things cool?

Sorry for the bad drawing but something like below. The top picture is my cab in whole(link in my sig), the back of the thermo device will go where that propogation dome is. The bottom pic is zoomed in on the open section i have above my veg chamber. All I would need to add that didnt come in the ebay auction is a 4 " fan, small box for the back (hotside) and 4" ducting.

Total cost will be like $200 but i will be able to operate it as just a AC or just a Dehumidifier. My CHHC-1 has controls for both independently based on thresholds i set. You could do it for chaeper but i am using 100W (two devices i posted a link to earlier).

 

[FullMetalJacket]

Thought you guys would get a kick out of this....It is a DIY "AC" solution like originally suggested on a larger scale...lol. Some people are crazy as hell. OMG

http://www.gmilburn.ca/ac/geoff_ac.html

 

[sunnydog]

it'll work. i did the same thing using a intercooler from a turbocharged car. one thing is you will get condensation on the outside of your heater core. just like a cold drink on a hot day. so your fan is going to be blowing this extra humidity back in to your cab. if your heater core is at ground level and your route the ducting vertically on the back of your cab that should help some of the water drain down, but your still need to get the water/ humidity of the air flow with some type of drain that will not be compromising your odor control.

That is why I mount the heater core in a cooler with a drain :wink:
As far as PITA, maybe a little bit. You have to replace the ice twice a day,AM-PM, but it is VERY QUIET, COOLS and DE-HUMIDIFIES!!
I thought about just using one of those 79$ air-cons from Home depot,things that suck are,

1- noise

2- power consumption, (I know the freezer will use power to cool the ice,what I mean is there is often not enough "free circuit breaker space" in a typical "grow bedroom" so this moves the burden of cooling somewhere else.

3- Air-con would probably have to cycle on and off alot when cooling such a small space

4-I can put an inline scrubber on the air return, bought A-c is not powerful enough to push through a scrubber,so I would STILL need to run the blower for that.

Sorry for not checking back here.

 

[sunnydog]

Thought you guys would get a kick out of this....It is a DIY "AC" solution like originally suggested on a larger scale...lol. Some people are crazy as hell. OMG

http://www.gmilburn.ca/ac/geoff_ac.html

That is actually pretty close to mine.
Mine will work better,though.
The enclosed heater core will be much more efficient.

 

[Kenny Lingus]

Hi! Cool idea guys....-but what size grill/coil you need for this, and hat circulation rates on pump and fan?

 

[sunnydog]

Hi! Cool idea guys....-but what size grill/coil you need for this, and hat circulation rates on pump and fan?

My original used a heater core from a 76 dodge wagon.
Blower size would depend on whether you use a coco can or not.
Pump- not too big, a smaller mag drive pump will do.

 

[eyes]

lets see the pic of it working.

 

[FarmerGreen]

I did something like this for a while, was good but used so much ice. I was doing it at the height of summer to keep the edge off the temp but my freezer couldn't freeze as fast as the cooler would melt it again. I bought big bags of party ice for a while but it was pretty high maintenance and buying that much ice seemed to defeat the purpose

 

[sunnydog]

I did something like this for a while, was good but used so much ice. I was doing it at the height of summer to keep the edge off the temp but my freezer couldn't freeze as fast as the cooler would melt it again. I bought big bags of party ice for a while but it was pretty high maintenance and buying that much ice seemed to defeat the purpose

How did you set it up?
what were you trying to cool?
Mine used about 8 liters a day (4 2 liter soda bottles). to cool a 400 watt cab with no cool tube.
With a cool tube for the lamp I would think you could do much better.

 

[darippa]

Would it be possible to use automotive coolant to help with efficiency of the water and also use the condensate from the heat exchange to drip to plants in a soil media?

 

[sunnydog]

Would it be possible to use automotive coolant to help with efficiency of the water and also use the condensate from the heat exchange to drip to plants in a soil media?

I thik the potential benifits of adding anti-freeze are minimal and not necessary.
The condensate in my plan drips in a separate box and out through a drain.
I GUESS you could use it , But I have some concerns about the lead used in the solder.