Go Back   Aquarium Advice - Aquarium Forum Community > General Aquarium Forums > DIY Projects
Click Here to Login

Join Aquarium Advice Today
Reply
 
Thread Tools Search this Thread Display Modes
Please support our sponsors and let them know you heard about them on AquariumAdvice.com
 
Old 05-12-2007, 03:54 AM   #1
Aquarium Advice Activist
 
Join Date: Feb 2007
Location: Princeton NJ
Posts: 153
DIY Thermoelectric Nano chiller for my 24-gal Nanocube

Well this is my first summer with an aquarium and I am starting to get worried as I live in a dorm/apartment with no airconditioning. My room is already getting up to 82-83 and my tank is hitting 85-86 so I decided I should investigate chiller options. I saw a thermoelectric cooler designed specifically for the nanocube http://www.nanotuners.com/index.php?cPath=34 but it runs $90 and requires cutting into my nanocube. I decided I could engineer a cooler from scratch that fits my needs. So here is my experiment.

First things first, I purchased a 320 Watt Peltier cooler off of ebay for $13. It can run at 24 amps at 15.6 volts and pull 243.5 watts of heat. I already have a 13 amp 12-15 volt power supply laying around, if that doesn't do the trick then I can probably find one on ebay if I look hard enough for $20-30 which will (I think I got the 13 amp supply for around $20 shipped). The nanotuners ($90) TEC cooler has an 8.4 V 2.5 power supply (or a 12 V 4.5 amp for an additional $32.95) and the ICE PRobe (over $103) has a 12 V 4-5 amp power supply. So I should beat the heck out of both of them.

Heat Exchanger. Here is what has been really driving me crazy trying to figure out how I am going to accomplish this. The main concern is corrosion (I am building this for FW but with intention to use or sell for SW). Pretty much the only metal you could directly use is titanium and not have to worry about corrosion. I noticed the nanotuners TEC heatexchanger was a dinky Delrin piece. I was contemplating all these solutions that I could fabricate myself such as taking thin walled silicone (or other plastic) tubing and pot it in some thermally conductive substance (glue or something) that could make the thermal contacts. Or I could mill a channel in something like ABS, Acrylic (something non thermally conductive nor corrosive) and then bolt a piece of metal on top to seal it. I could drill and tap holes to put pipe fittings in. I could simply coat the side of the metal that will contact the water with some film (either spray on paint/epoxy or just lay down a very thin piece of something like polyamide) to prevent corrosion. Although the film will probably have a low thermal conductivity, it will be so thin it will not affect the heat transfer that much. But then I decided it would also be cool if I could devise a setup that most people could use regardless of whether they had access to a machine shop or special tools. So then I found out that there are heat exchangers made for liquid cooling CPU's that are almost exactly what I wanted to build. Here are a few of interest

http://www.coolermaster.com/index.ph...al=RL-D3A-CNU1. This is the one I think I am going to use, it has 1/4 tube fittings and the copper plate is removable so I can just take it off and spray or coat the one side that will contact the water to prevent corrosion.

Another one that is smaller and designed to fit a CPU
http://www.directron.com/clw0038.html


http://www.directron.com/chc35d06.html This one was interesting because it is gold plated and rather cheap. Although I found out that gold will corrode in salt water (although very slowly). I could also coat the inside but it seems like it will be more difficult.

There were a few other CPU/HD/GC heat exchangers that looked promising.

So now I have the heat exchanger, I either thermal tape the heat exchanger to the Peltier element or clamp it somehow, but now I need a fan.

Fan: I ordered a really crappy one (I am having regrets now) for $5 shipped. I think I will need a better one.

I have a few things in mind depending on exactly what I get such as building a new metal plate that can screw into both the heat exchanger and the fan. Let me know what you guys think. I think if this works out it could easily be scalable to larger systems (more gallon tanks). There is a next higher size Peltier element on ebay for about $19. The harddrive heat exchangers can easily accommodate two of these larger elements in parallel which if you had the proper power supply could be pulling a total of 60 amps at 15.4 volts. Each of the larger TEC can transfer 270.5W so thats a total of 541W theoretical. Of course you could expect maybe 1/2 that by the time it finally reaches your tank but thats still a good amount of cooling. That is about the amount of heat drawn (and thus dissipated into heat) by most larger tank's light and pumping systems.
__________________

__________________
Make it idiot proof and someone will just make a better idiot.
helicopter is offline   Reply With Quote
Old 05-12-2007, 04:10 AM   #2
Aquarium Advice Addict
 
Join Date: Nov 2006
Posts: 2,254
That was a mouthful there. From what I think I read, you are looking at the prebuilt computer system designs. All metals corrode, but it's really not much to worry about until a ways out. Copper has the best heat transfer of just about any metal that is readily available, which is why it is chosen for computer as well as industrial applications.

The only problem with these is your coolant. If your coolant is water, what is going to keep it from heating up just as hot as the tank, making heat exchange useless? If you're running a fan, a fan over the top of the tank might cool off just as well.
__________________

__________________

theotheragentm is offline   Reply With Quote
Old 05-12-2007, 04:52 AM   #3
Aquarium Advice Activist
 
Join Date: Feb 2007
Location: Princeton NJ
Posts: 153
I am especially worried about copper because if it dissolves in the water it can kill inverts. I was reading up on gold plating and saw a salt water fish hook company that gold plates their hooks and said it prevents them from rusting longer than SS hooks (typically several months). Therefore it appears that in a SW environment even the gold would rust within a relatively quick time frame. What is especially to worry about is that when the metal rusts, particals will fall off and possibly dissolve in the water which can harm the fish.

Please let me clarify my setup. I am not planning on using an existing CPU cooling system (they tend to be very expensive) just a heat exchanger ($20-$30) used for such applications. What I would be doing is actually the opposite of the what a cooling system in a computer would do. I would be cooling the heatsink with the peltier element (and ejecting the heat off of the hot side with another heat sink and a fan). That way the water from the aquarium will flow through the chilled heatsink and then return to the tank.
__________________
Make it idiot proof and someone will just make a better idiot.
helicopter is offline   Reply With Quote
Old 05-12-2007, 11:59 AM   #4
Aquarium Advice Addict
 
Join Date: Nov 2006
Posts: 2,254
Holy crap. I looked that up on Wikipedia. I had no idea such things were possible. My background is purely industrial. I wonder if that would work large scale. It probably wouldn't be cost effective though.
__________________
theotheragentm is offline   Reply With Quote
Old 05-12-2007, 03:22 PM   #5
Aquarium Advice Activist
 
Join Date: Feb 2007
Location: Princeton NJ
Posts: 153
Its not as efficient as a regular refrigeration cycle (like in air conditioners and refrigerators) so it is only really cost effective in small scale devices where the cost of doing the whole (compressor, high pressure tubing, high pressure pump...) is cost prohibitted.
__________________
Make it idiot proof and someone will just make a better idiot.
helicopter is offline   Reply With Quote
Old 05-14-2007, 10:09 AM   #6
AA Team Emeritus
 
roka64's Avatar
 
Join Date: Mar 2006
Posts: 13,860
Send a message via AIM to roka64 Send a message via Yahoo to roka64
How about a fan? My fan dropped my temp from 82-83 to 78.
__________________
Age is relative, you are only as old as you act....of course, this works in reverse....

Questions loved, heeded advice greatly appreciated!

Vote for AA
Good reading about:
Nitrogen Cycle
Fishless Cycling
Need more help?
Articles
Acronym List

--Scott
roka64 is offline   Reply With Quote
Old 05-14-2007, 02:47 PM   #7
Aquarium Advice Freak
 
Join Date: Feb 2007
Posts: 216
Quote:
Originally Posted by roka64
How about a fan? My fan dropped my temp from 82-83 to 78.
How often do you have to top off you water?
__________________
pinda is offline   Reply With Quote
Old 05-14-2007, 03:02 PM   #8
AA Team Emeritus
 
roka64's Avatar
 
Join Date: Mar 2006
Posts: 13,860
Send a message via AIM to roka64 Send a message via Yahoo to roka64
About every other day. I am also using 150W MHs.
__________________
Age is relative, you are only as old as you act....of course, this works in reverse....

Questions loved, heeded advice greatly appreciated!

Vote for AA
Good reading about:
Nitrogen Cycle
Fishless Cycling
Need more help?
Articles
Acronym List

--Scott
roka64 is offline   Reply With Quote
Old 06-12-2007, 03:50 AM   #9
Aquarium Advice Activist
 
Join Date: Feb 2007
Location: Princeton NJ
Posts: 153
Pictures

http://www.nano-reef.com/gallery/dat.../IMG_00351.jpg
This is the heat exchanger. It was machined from 1 inch acrylic. All the edges were bevelled on a belt sander and then finely sanded/polished. The pictures really do not do it justice, it actually looks really nice in real life. One side of the piece was milled out (a channel for water to flow through) and then capped with the titanium plate (screwed in with 10-32 screens and sealed with RTV). I have not hooked everything up but she appears to be "sea worthy" in that I can create suction with my mouth on one hose barb while plugging the other hose barb and it was hold the suction for a long time as if I were sucking directly into a glass bottle.


http://www.nano-reef.com/gallery/dat.../IMG_00271.jpg
In this view you can see that 6 counter sunk through holes for the 1/4 20 machine screws which bolt onto the heatsink to sandwhich the Peltiers.


http://www.nano-reef.com/gallery/dat.../IMG_00292.jpg
http://www.nano-reef.com/gallery/dat.../IMG_00282.jpg
Two views of the Titanium back plate. One side of the plate is sealed inside the cavity and exchanges heat with the water. The other side of the plate will contact the Peltier coolers (with Artic Silver 5 for good contact). The image makes it appear as if it is rough but it is actually sanded very smooth.

http://www.nano-reef.com/gallery/dat.../IMG_00221.jpg
http://www.nano-reef.com/gallery/dat.../IMG_00242.jpg
Large black anodized aluminum heatsink with two thermally controlled computer fans on the back (Thermaltake 92 mm Smart Fans).


http://www.nano-reef.com/gallery/dat.../IMG_00373.jpg
The Peltier elements contact the reverse side of the heatsink. In this image you can see the tapped 1/4 20 holes for mounting the heat exchanger as well as milled out countersinking to provide clearance for the heads of the screws holding the titanium plate to the acrylic.

http://www.nano-reef.com/gallery/dat...m/IMG_0039.jpg
Fits like a glove on top.


http://www.nano-reef.com/gallery/dat...m/IMG_0051.jpg
125 amp 12 V power supply I got on ebay for a ridiculously good deal ($80). It is used to power both Peltiers which at 12 at their peak (when you initially turn them on and they are still cool they draw the most current) they will draw around 40 amps total. After heating up their hot sides they each settle down to about 12 amps each.
__________________
Make it idiot proof and someone will just make a better idiot.
helicopter is offline   Reply With Quote
Old 07-22-2007, 04:01 AM   #10
Aquarium Advice Activist
 
Join Date: Feb 2007
Location: Princeton NJ
Posts: 153
Here is the heat exchanger







__________________

__________________
Make it idiot proof and someone will just make a better idiot.
helicopter is offline   Reply With Quote
Reply

Tags
chi, chiller, cube, diy, nano, nanocube

Please support our sponsors and let them know you heard about them on AquariumAdvice.com

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
DIY Thermoelectric heater? partypalooza5 DIY Projects 1 11-17-2009 07:24 PM
Thermoelectric Chiller / Heaters bhammer General Hardware/Equipment Discussion 16 08-06-2009 01:09 AM
Chiller Selection for 28 Gallon Nanocube HQI jonboyb General Hardware/Equipment Discussion 4 08-26-2008 03:16 PM
12 gallon nano? Chiller Needed? Squado Nano Reefs 5 06-17-2006 02:17 AM
Help Requested - DIY chiller and DIY Ca reactor dansemacabre DIY Projects 5 12-28-2003 12:54 PM







» Photo Contest Winners








Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -4. The time now is 09:19 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.