Arcan3 Posted September 5, 2003 Share Posted September 5, 2003 i saw the ice chiller thing (iceprobe by coolworksinc...) and i noticed that its just a cpu heatsink w/fan !! im guessing the thing on the back is just a aluminum bolt or sum... anyone can make one of those for like 20 bucks ussing a good cooler... but i think its easier just to get a ater cooling sistem from a pc and put it in... (2 hoses a pump and a radiator... u can hide it in the base or the top... and if the pump get damaged its at the most a 5 $ pump...) Link to comment
Arcan3 Posted September 5, 2003 Author Share Posted September 5, 2003 oh btw ... the thing in between the bolt like structure and the heatsink is just a peltier... (i think thats the name i havent been to overclocking forums lately...) Link to comment
adinsxq Posted September 5, 2003 Share Posted September 5, 2003 these might help http://www.nano-reef.com/forums/showthread...=&threadid=4252 http://www.nano-reef.com/forums/showthread...&threadid=11816 http://www.nano-reef.com/forums/showthread...&threadid=13762 Link to comment
MrConclusion Posted September 7, 2003 Share Posted September 7, 2003 There's no way you'll get the thing built and running reliably for less than buying the iceprobe. For one thing, where will you get a SW-safe cold probe? (The same thing goes for making a water radiator, there's no way you can use anything with aluminum, copper, or mild steel) For another, the tolerances for the hot/cold surfaces are very exacting, or the Peltier element will fail or lose efficiency. Plus, you're going to need a DC power supply and a HSF capable of dissipating at least 50 watts. If you manage to get this assembled and running for less than $100, then you definitely rock and I would love to see pictures. However, in my experience, this is one of the most dreamed-about DIY projects - but the smart money is on a preassembled unit. Link to comment
Arcan3 Posted September 9, 2003 Author Share Posted September 9, 2003 umm well i have a better idea on how to do this it takes a water pump (so i dont have to get a probe) 2 peltiers 2 drilled copper blocks and 2 heatsinks... tank+water pump---blk1+pelt+heatsk-----blk2+pelt+sink---tank since the pelts u need are 16w... u dun need that much power.. and they cost 15$ each... the water pump 10(guess)$ 2 heatsinks w/fans about umm really dun know this one since i have like 30 laying round (intel hsf's suck on chips but they would serve here) ohh yah,,, and thermal paste but it comes with the hsf or the pelts... Link to comment
sdboogie Posted September 11, 2003 Share Posted September 11, 2003 It's funny that this thread has come alive again. I have thought hard and long, spend a whole day surfin and think I came up with a solution. The easy part is the peltier device. Those are $15 on ebay even for the big 120W one. The heatsink and fan are also easily acquired for 10 bucks. I haven't figured out exactly the probe that goes in the water but was thinking at very least a stainless steel bolt. The expensive part is the controller and the power supply for the peltier. I found at mcshaneinc.com controllers for about $50. They are not digital but once it's dialed in who cares. The temp probe that plugs in is about $12. Then all you need is a power supply. Those look expesive but I was thinking a modified AT computer power supply. I just don't know it those will throw down 120W. Any way, the total is somewhere around $100 if the AT PS works. You could mount it in some sort of metal box barely bigger than an AT PS with power switches and a hole to adjust the POT on the controller. I will probably try it before next summer maybe sooner depending on funds. It looks like a fun project. A bonus is that huge 120W peltier would probably show greater results than the iceprobe. For not too much more you could add multiple cooling probes and mount them in an AquaClear HOB for larger tanks. What do you think? Link to comment
sdboogie Posted September 12, 2003 Share Posted September 12, 2003 Here's a diagram of the setup. I verified the AT Power supply has enough juice to push a 130W peltier. The cool thing about using an AT PS is that the original pigtails are already made to push fans since I'll need two, one for the peltier and one for the PS and controller. My revised cost for this is about $125 including the piece of stainless steel round stock. I have a call in to a welder friend for a good way to interface the peltier to the steel. This beats $170 for the iceprobe and also has alot more power. Until it is built, there won't be any specs on cooling ability but even the iceprobe stats seemed pretty weak to me. Link to comment
reefer20G Posted September 12, 2003 Share Posted September 12, 2003 Sdboogie, awesome idea. Anymore deatials on the controller and temp sensor? That part is a little over my head. Oh, what is the good way to interface to the steel? Link to comment
adinsxq Posted September 12, 2003 Share Posted September 12, 2003 i think iceprobe+controller is closer to $150 than $170. Link to comment
sdboogie Posted September 12, 2003 Share Posted September 12, 2003 The controller is from McShane Inc. www.mcshaneinc.com The model number is 5CX-753. The controller has a pot to adjust the temperature setting. It basically turns on and off a 120V power line. That would connect to the AT power supply to drop the power down to 12V to power the peltier and fans. The temp sensors are also sold at mchane and are listed on the page with the 5CX-753. Yeah, I'm no electrician but I think I can hack through this. I might even ground the damn thing. Link to comment
foo Posted September 12, 2003 Share Posted September 12, 2003 sdboogie - That won't work. I was farting around with this stuff, so I know at least that much... I tried using a several different power supplies, among them an ATX power supply to drive a 20W, an 85W and a 120W peltier before I realized that won't work very well. From my experimentation I began to suspect that the optimum performance was only along a specific voltage/current curve. I got better cooling with a smaller power supply than with the ATX. I did a little bit of homework and confirmed what I suspected. Too bad I didn't do the homework before jumping in and trying this stuff. Your AT power supply will likely supply too much current and not enough voltage and not drive your peltier efficiently. For now I gave in and bought an iceprobe so I can get my tank going but I haven't given up on the DIY idea. I just need to find a power supply that outputs the correct voltage and current at a cheap price and find a better probe. I was using a titanium bolt but I think I need a larger probe. Titanium I discovered isn't a very good conductor of heat. If I had access to a lathe I'd take a billet of aluminum and make a heat exchanger like an iceprobe. Coolwork's iceprobes contain an aluminum core. Do some research on the peltier you bought and find out the performance curve so you can drive it to optimum efficiency. Link to comment
sdboogie Posted September 12, 2003 Share Posted September 12, 2003 I just looked at a power supply today. The yellow lead that plugs into the motherboard is rated at 12V and 12Amps which equals 144 Watts. Which is in the power range of a 130 - 160W peltier that I saw on ebay. What leads off of the power supply were you using? Please share what you think the correct voltage and current is. Maybe the PS on the iceprobe has some specs. It sounds like sound theory to me, but like you said, maybe the tests will prove diferently. I found this on a listing for a 130 - 160W Peltier on ebay - Q: How do I power the TEC? (can I wire it into my computer's 5-volt or 12-volt lines?) A: A TEC requires a lot of current to work at maximum potential. A 130 Watt TEC will consume 15 Amps of current at 12 volts DC (which is possibly the entire 12-volt capacity of some computer supplies!). It is possible and sometimes practical to 'under-power' a TEC. A 130 Watt TEC will still get extremely cold with only 2 Amps of current! If you intend to cool your CPU with a TEC then you must consider the maximum output capacity of your computer's PSU (Power Supply Unit) and also the consumption from your computer's components (CPU/Hdisks/Graphics Card etc). Does anyone have any specific voltage and amperage combinations that they have used with a Peltier. Please share. I looked at ebay again and a 85 - 105W peltier only draws a max amperage of 10A. So even if the project stepped down to the smaller size, it still seems to be in the range of the AT PS. Link to comment
bertz_maru Posted September 12, 2003 Share Posted September 12, 2003 what is an peltier exactly? if anyone builds a good chiller post some pics and instructions.... im interested... Link to comment
sdboogie Posted September 12, 2003 Share Posted September 12, 2003 A peltier is a thermoelectric device. I'm not sure what the material is maybe ceramic or something. Basically it's a square flat looking thing with two wire leads coming from one side. When you apply power to the leads it facilitates and energy exchange. One side gets hot while the other side gets cold. The hot side needs a heatsink and fan to disipate the heat while the cool side gets cold enough to form ice crystals. You could also supply the hot and cold to create a current out to the wires. It's not the most efficient thing but it works. One of the common uses is to cool processor chips in computers. Slap the cold side to the chip and a heatsink and fan to the hot side, a little power and violla. Still looking for input on the ideas presented. Link to comment
bertz_maru Posted September 12, 2003 Share Posted September 12, 2003 so are you plainning on glueing the cold side to your tank? and then putting a fan and heatsink on the other? im curious... Link to comment
sdboogie Posted September 12, 2003 Share Posted September 12, 2003 The plan is to find a way to mount some sort of metal probe to the peltier and dangling the probe into the water in an HOB. One of the things I haven't figured out yet is an efficient way of going from the square peltier to a round shaft of the cooling probe. Maybe welded? I'm not sure at this point. I'm waiting a call back from a welder friend who hopefully can give me some ideas. Link to comment
bowfrontsrock Posted September 29, 2003 Share Posted September 29, 2003 How bout this, take a small cooler and a ton of airline tubing. Make a real tight coil of airline tubing in the cooler. Fill the cooler with ice. Drill two holes in the cooler, put in airline tube connectors and seal with silicone. Attach an airpump. Put an airstone into you HOB. You probly have to replace the ice every other day......but it's like 20 bucks instead of 150 and crazy electronics. Might bring it down a few degrees. Link to comment
HockeyGuy88 Posted October 1, 2003 Share Posted October 1, 2003 I actually researched this quite thoroughly when I first set up my 5G nano in the dead of summer. I noticed that my temps would regularly spike above 86 deg (no, there was nothing but sand and water in there) and saw that same IceProbe item. I couldn't bring myself to pay that price for something I knew about already. I work with computers for a living and am very well versed in Peltier coolers and knew that there is a way to do this, so I did some more looking. Here's what I found, and it works great, at least in my setup. The following link is to the controller circuit. Click Here This link is to the page that shows how to build the temp probe (thermistor). Click Here . Now I Highly suggest that the thermistor is encased in aquarium sealant, though pressed up against the Stainless Steel tubing. By doing it this way, it gives a "buffer" of a couple of degrees so it isn't constantly cycling on and off. This kind of tubing can be found in some auto parts stores as Brake Line. Clean it thoroughly with alcohol before using in your water. Be sure to bend it over the top of your tank so the thermistor is submerged. The Peltier is then attached to the relay, connected to the area that states "To Thermostat Circuit". Make sure you have a good cooling fan and heatsink on the hot side of the peltier, and attach the cold side to the side of your tank. I used Arctic Silver Thermal Epoxy and basically glued it to the side of the tank. The Arctic Silver is well known with the Computer Overclockers as it works Very well. To set the temp, simply get one of those cheapy digital thermometer probes in a glass of water that is accurate with the temp you want in your tank (i.e. if you want 76 deg in your tank, get a glass of water that's 76 deg), dunk the thermistor in the water and power the circuit up, adjust the potentiometer until the LED flickers. Temp is roughly set, but you may need to adjust slightly on the fly. While I know this isn't for the less adventurous, it's a pretty simple circuit, cheap to make with ebay and Rat Shack (or your choice of electronic supply shops), not outrageously ugly, and very effective. My 72W pelt will cool 20G of water about 4-5 deg for about $30 and a half hour worth of soldering. Best of all, it works and will work well provided you get a good heatsink and fan for the hot side of the pelt. Special thanks to those homebrew guys that designed the circuit to cool the homebrew beers! I hope it works as well for you as it did for me! BTW, makes a nice sump chiller on your bigger tanks too, though you may need a couple of more to cool the volume of water you are moving. Link to comment
edmund67 Posted October 1, 2003 Share Posted October 1, 2003 I'd use an atx pwr supply. Use the constant supply voltage that is always on to power your comparator circuit. Have the output of the comparator circuit going to a 555 timer. Do some calcs for your RC (resistance capacitance) time constant to get a 1 min pulse from the 555. have the 555 output to the control lead to turn on the atx supply that will power ur peltier. I think they sell the 555 timer engineering note book in Radio shack as well. Link to comment
HockeyGuy88 Posted October 1, 2003 Share Posted October 1, 2003 I did forget to mention that I used an old ATX power supply to supply the voltage to the circuit, though I do not have it on a 555 timer. Instead, I had it on an X-10 controller that was set to only come on during the hottest times of the day. The timing circuit that you speak of would be a very nice addition to help save energy without the need for another X-10 unit. Now that it's cooler out, I simply turned it all off as the temp doesn't get above 76 Deg any longer. Maybe I ought to redo the schematic to reflect the timing circuit. Link to comment
Dingo Posted October 1, 2003 Share Posted October 1, 2003 Of course, you could just run about 25 feet of plastic tubing into your basement and back into your tank. If it was too cool, your heater would warm it up again. Assuming that you have a basement. And that your wife wouldn't smack you silly. Link to comment
edmund67 Posted October 1, 2003 Share Posted October 1, 2003 Well I have a Radio Shack 555 timer notebook laying around. attached is the circuit. U may have to switch the inputs of ur Vref and input around to get the right output state to trigger the circuit. Attatched is a scan of the circuit. No rush to upgrad, since summer is over. U have some time to think about it. Link to comment
edmund67 Posted October 1, 2003 Share Posted October 1, 2003 I should breadboard this and test it. Bout how much time (pulse width) do u need? Link to comment
HockeyGuy88 Posted October 1, 2003 Share Posted October 1, 2003 Edmund, If you have the resources to breadboard this bad boy up, please do. As far as pulse width, I'm not quite sure what exactly I would need. I know it takes 15 secs to get the pelt to operating temp and approx the same for warm up/cool down. Outside of that, I have no idea as the thermistor probe was cycling the relay and I never really paid real close attention to the time intervals. I DO know that when I first fired up the unit, it ran constant for about 5 mins before it cycled on and off, and with the buffer figured into the probe design, it would take about 3-4 mins before it kicked back on again once at temp. As far as the "on" time for the pelt, it depended on how hot it was ambient, but seemed as if it averaged in the 30 sec - 1 min range. I'm guessing if we could get a 1.5 minute to 2 minute dwell time, we'd be doing real good though, even on the REAL hot days, so long as we stayed in the 1 70W Pelt to 20 Gallon for 3-5 degree drop in temp range. edited: Now that I think about this, I know EXACTLY where to use this timing circuit! There's a mod for ATX power supplies where you can cut 2 wires on the main connectors for the motherboard and put in an on-off toggle for those Power Supplies that don't have one on the back of the case. If we could cycle the power right there, it would power up and down the supply perfectly, saving a substantial amount of electricity... Link to comment
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