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Discussion Starter #1
my thinking is to a take a 60 watt-100 peltier device right after the radiator sandwich in between a water block and a conventional cooler for the same CPU does not have to be the same CPU as whats in the system the idea is one side gets cold to chill the water the other side gets warm and is vented out of the case my thinking is to use a dell hood or something similar to directly vent this device and also insulating the water block would not hurt but not expecting to lose allot from that point my only worry is condensation so thinking I should insulate the tubing after the peltier device up to the CPU since not expecting the CPU block to stay bellow room temp after all of this what would be the safe temp reletive to room temp on a hot summer humid day my thinking is 10 degrees bellow room temp

and does anybody make pre insulated tubing my guess is want to avoid fiberglass and foam type insulation foam might be usable if covered with more tubing but do not want to stress the fittings a hard tubing might help with this rather it be strait runs only or tubing that resists bending enough to prevent extra pressure from the foam
 

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Dew point isn't a fixed number of degrees below room temperature. Dew point depends on relative humidity and ambient temperature. It's entirely possible to have a dew point that's 50°c below 25°c or at 25°c in a room that's at 25°c.

If the water temperature is going to be below the ambient room temperature then any radiator in the loop is going to be adding heat to the loop.

I believe you need more than just air blowing on the hot side of a pelt. You need some kind of active cooling. like a cpu cooler or water cooling.
 

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Discussion Starter #3
could go with simple pipe insulators the issue is they do not make a great seal with that seam so then I would have to wrap them in tape not looking for a perfect look just want it to keep it cool could also use green it foam its bright green similar to great stuff but I would have to cover it with venal tubing so to look good all the other tubing would have to be green just want it to not look ugly but pipe insulator wrapped in colored duct tape would not be to bad just have to caulk the ends and shave a little right down the center from the seam to get a good tight fit so that no air ever touches the tubing and this is kinda a key factor or it will mildew around the tubing so really like the venal tubing idea for that reason and some colored duct tape unless I can get colored tubing of the right size or color the clear stuff from the hardware store
 

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well my setup was gonna be water block on CPU very large radiator then the peltier device then pump

in this setup the radiator takes the water down to almost room temperature then the peltier device cools it down even further then that chilled water goes into the pump witch will be inside a foam block to reduce its noise then back to the CPU if I keep the cold line insulated it should reduce the chances of condensation not trying to keep the CPU at 50 degrees just want a little bit of an extra edge on cooling without having a radiator from a Honda civil in my loop if the water coming in was at 60 F degrees and the cpu was at 80 F I would be happy that is the type of temps I kept with air cooling with non over clocked systems not the big issues do not want any clogs or leaks including ice so having chilled water go into the pump seems like a good idea as we are not going for ice or temps that would make it brittle but over heating is something we want to avoid colder is better when electricity is involved iwater cooling is new to me I have known that existed for some time never used it and a pre built cooler is not in the picture not when you want to get a thread ripper clocked to 3.9 ghz witch is still in spec when the boost function is considered just have to be able to maintain that might settle for 3.8 but nothing lower also do not want a loud system whisper quiet would be nice so likely gonna use 2 core x9 cases stacked so the top case can be insulated for noise and have its own isolated air flow for the radiators all sucking into the case so that noise is expelled into the room this case is great for another reason it allows the radiators to be mounted inside behind filters

https://www.ebay.com/i/262135458397?chn=ps&dispItem=1 that unit would be a good heat sink for the peltier device as its 80 watts without any fans add some major down draft even with all the heat from the radiators expecting at least 150watts of cooling if I used a 200 mm fan right bellow it and channeled that air through the front or back and not down into the bottom case
 

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yes I guess I should have explained a bit better a water block on one side and a CPU cooler with heat pipes or icepipes on the other side and a massive fan and shove the entire heatsink into a fan 200 mm fan shroud to get max air flow my goal is to get more capacity without adding another radiator but yep if also worth noting is that I do not want to go down to freezing so a radiator is a good safe guard against freezing unless I want to go with glycol but then I lose some performance my aim is to be 10 degrees bellow room temp this seems like a safe margin to prevent condensation but we could still see 100 percent humidity like just before a storm then I would have to be able turn peltier devices down a bit and allow for slightly higher then room temp this is the trade off I would have if I went with only a peltier devices having both in the loop is also a trade off might be able to run a bit cooler and be able to turn off the peltier device to run with just the radiator as option on humid days but with it on will be using allot more power for a few degrees cooler also could turn off the fans to the radiator

my thinking was to get the water to the CPU at 10 degrees cooler then room temp by the time it goes back to the radaitor it will have excess heat to get rid of and not be a waste but your right IF i kept the system running at 45 degrees I would be losing cooling through the radiator so my design was to have enough radator cooling to get things down to almost room temp and a small 60 watt peltier device to add that little extra chill and to keep things really low at idle

can a peltier devices be powered via pwn I do not see why not my guess is if not it would be due to the pulsing witch I could even out with a capacitor as a resistor setup would be self defeating reduce cooling by adding more heat PWN is the better solution even if a massive half farad cap is needed witch would be fine since the system will be on all the time but also just use the PWN to ramp up the power slowly starting out at 7 volts would be fine but that might not work out as expected due to the nature of caps my method would be to install a monetary switch press and hold to allow a resistor to do the initial charging release the button and the button by passes the resistor other wise known as a normally closed switch push to open or in simple terms push the button to be off like the light in your fridge its kinda a pain but only plan on turning off the system for loop maintenance for any period of time the cap will hold most of its charge for 3 hours or more a delayed relay is another option same concept except its automatic note no power to the peltier device while cap is charging but the radator will be able to do the job all on its own for a little bit or on humid days it has to the peltier device is starting to look like a real pain if it can not take raw pwn power
 

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Discussion Starter #8
https://electronics.stackexchange.com/questions/28634/how-to-drive-a-peltier-element wow that is so dead a real pain no pwn as in it will just create more heat at lower voltages as I understand my guess is we have a negative resistance issue

and you can not simply turn it on and off due to thermal shock issues that will increase ware but might not be an issue in a water cooling setup then might be worse due to the lack of external heat and the rapid cooling from the water that still runs through turning it up and down might work

a high frequency pwn might work if its completely buffered as in no caps and does if it does not have issue with the pulsing as PWN does not turn the power down but rather it turns it off and on at high frequency so the voltage is really unchanged and the current remains the same
 

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1.) You have not delt with what happens if the temperature of the water entering the rad in below room temperature causing the water to be heated back to room temperature by the rad..
2,) Motherboard fan headers don't supply anywhere near enough power to run a pelt.
 

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did some reading cap on a pwm is a bad idea you could how ever make a simple buck converter by adding a diode and a inductor this is still better also worth noting is yes thermal shock is an issue but at high frequency its a non issue but not advisable as the over all effectiveness goes down at low duty cycles

bottom line it looks like would be better off with a compressor type system to cool off the water for 2 reasons first we could reduce humidity the key killer to the usability of the system and second is its far more efficient a peltier is removes 1 watt of heat with 4 watts of input this is pretty low compared to a radiator system a compressor based system removes about 4 watts of heat with 1 watt of power so a 100 watt compressor system would give you 400 watts of heat removed knew peltiers were easy to install but a cost and do not think they can make these units any more power effective as its part of the effect its we might be able to over come this effect by adding a second peltier device to recapture the heat into eletical power and send it through for another run if this feed back loop was able to catch allot of the heat generated it could be on par with compressor type units but they do not make such a device yet yes they work in reverse were heat passing through a peltier device will give you power would be nice if that power could be used to run your pump
 

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https://physics.stackexchange.com/questions/106805/how-much-electricity-can-be-produced-by-my-thermoelectric-generator so that is the key to getting a peltier device to be more effective when some of the passive heat generated by the device is recaptured and used to power the device also if you could power your pump that would be a nice option right now by the time a simple loop is done your looking at 300 watts of heat dissipated 20 watts for a pump and another 10 watts for the fans this is 1 watt of power for 10 watts of heat removed a peltier is really on the other end of the scale tripple the power used and gain extra 60 watts of heat removed just to go slightly bellow room temp a 60 watt peltier device would allow me to go lower temp of the cpu by another 10 degrees that is a big deal for some people but if you want to do that I would look into using a water chiller for like a water fountain or such maybe not a water fountain as that would not be for constant duty load but something along those lines as you could also cycle some of the air in your case past it as well and then you just have to drain the condensate if your like I have a dedicated firewall in the basement and a big switch for all my devices just run a hose through that hole along side the network cables and to the laundry room sink drip drip gonna look for such a pre built device
 

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I've been thinking of a similar setup lately.
My idea is the same as yours chicagogenius, I guess: Not getting the water too cold to produce condensation but just give you a small push.
What I've been thinking is if a setup that's only with water cooling gets the water temperature to let's say 35C (with an ambient temp of 23C), we can lower that water temp to let's say 25C with the peltier. This will be still quite safe for condensation issues and a simple controller for the peltier should keep temps stable. I have a spare Noctua NH-D15 so I'm pretty sure I can cool any peltier below 300W
biggrin.gif

Something else that I've been thinking of is making this peltier thing a separate unit with it's own enclosure, PSU, controller and so on, and having quick disconnect ports on my case. This way If I don't want to use the chiller for some reason, I can always remove it and just put a bypass hose to the two quick disconnect ports. A temp sensor inside the chiller part will be monitoring water temperature and turn on and off the peltier to keep everything at room or near room temperature. You can even use a second temp sensor to monitor room temp and change the on/off point of the peltier to keep everything safe.
 

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OrionBG, for what you're going to pay for all the parts and programming that you will need it would be cheaper to just hire someone to sit next to you whenever you run you computer and manually (turn a knob?) adjust the temp manually.

I've had such a system priced out and about $1,000.

And, that's no leak QDCs.
 

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It is quite simple electronics actually. You need a PSU for the peltier, about $25, one peltier, one relay, two temp sensors and in worst case scenario an Arduino (one of the small ones) all and all probably a weekend project and no more that $50 for the electronic part. The rest you will need is a big radiator for the peltier (I have the Noctua NH-D15), a CPU Water block for the peltier cold side (I have one), some tubing, some fittings, some kind of a case (use your imagination here
smile.gif
) and two QDC's...
I'm not saying it is an easy project but it is definetely not $1000. More like $200 - $250 if you have to buy everything...
Also a 3D printer comes quite handy in such projects
smile.gif
(I built one)
 

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Quote:
Originally Posted by OrionBG View Post

I've been thinking of a similar setup lately.
My idea is the same as yours chicagogenius, I guess: Not getting the water too cold to produce condensation but just give you a small push.
What I've been thinking is if a setup that's only with water cooling gets the water temperature to let's say 35C (with an ambient temp of 23C), we can lower that water temp to let's say 25C with the peltier. This will be still quite safe for condensation issues and a simple controller for the peltier should keep temps stable. I have a spare Noctua NH-D15 so I'm pretty sure I can cool any peltier below 300W
biggrin.gif

Something else that I've been thinking of is making this peltier thing a separate unit with it's own enclosure, PSU, controller and so on, and having quick disconnect ports on my case. This way If I don't want to use the chiller for some reason, I can always remove it and just put a bypass hose to the two quick disconnect ports. A temp sensor inside the chiller part will be monitoring water temperature and turn on and off the peltier to keep everything at room or near room temperature. You can even use a second temp sensor to monitor room temp and change the on/off point of the peltier to keep everything safe.
guys that is really not how TEC's work. if I was to use a 300wattt TEC on a CPU only water chiller loop with the CPU at load, I would be lucky if I could keep the cold side water temps at ambient room temperature. keep in mind that a single TEC running at 300 watts will produce a lot of heat, it will take a 360mm and a 240mm radiator to cool that single TEC down. (do not buy ebay TEC's) a good TEC of that size will cost $65 or more, a 400watt TEC will cost $80 or more. a 400watt TEC will hold a single CPU at load, with the water temps, between 5C to 10C below ambient. with my TEC water chiller system, just in TEC cooling I had 1200watts or 9 TEC's, that held my PC system of 600watts, while at load, the water on the cold side of the TEC's was at 7C below ambient. basically what I am saying, is that to get anywhere with TEC's as a way of chilling the water, you need to start with at least twice the amount of TEC cooling in watts, as the amount of the load being cooled in watts.
 

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Quote:
Originally Posted by OrionBG View Post

It is quite simple electronics actually. You need a PSU for the peltier, about $25, one peltier, one relay, two temp sensors and in worst case scenario an Arduino (one of the small ones) all and all probably a weekend project and no more that $50 for the electronic part. The rest you will need is a big radiator for the peltier (I have the Noctua NH-D15), a CPU Water block for the peltier cold side (I have one), some tubing, some fittings, some kind of a case (use your imagination here
smile.gif
) and two QDC's...
I'm not saying it is an easy project but it is definetely not $1000. More like $200 - $250 if you have to buy everything...
Also a 3D printer comes quite handy in such projects
smile.gif
(I built one)
What about humidity and dew point? And who's going to write the algorithms?

I'm not trying to shoot down this idea, it's a good one, just make sure the OP knows what he's getting into.
 

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Quote:
Originally Posted by toolmaker03 View Post

guys that is really not how TEC's work. if I was to use a 300wattt TEC on a CPU only water chiller loop with the CPU at load, I would be lucky if I could keep the cold side water temps at ambient room temperature. keep in mind that a single TEC running at 300 watts will produce a lot of heat, it will take a 360mm and a 240mm radiator to cool that single TEC down. (do not buy ebay TEC's) a good TEC of that size will cost $65 or more, a 400watt TEC will cost $80 or more. a 400watt TEC will hold a single CPU at load, with the water temps, between 5C to 10C below ambient. with my TEC water chiller system, just in TEC cooling I had 1200watts or 9 TEC's, that held my PC system of 600watts, while at load, the water on the cold side of the TEC's was at 7C below ambient. basically what I am saying, is that to get anywhere with TEC's as a way of chilling the water, you need to start with at least twice the amount of TEC cooling in watts, as the amount of the load being cooled in watts.
The part about the 300W TEC was intended as a joke towards the insane cooling abilities of the NH-D15 cooler.
Also we are pretty aware how a TEC is intended to be used but we don't need such cooling power. we just want to lower the water loop temp a little (but not below ambient as condensation will occur).
But anyways thank you for the info! I'm sure it will be useful for people going that road.
 

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Quote:
Originally Posted by billbartuska View Post

What about humidity and dew point? And who's going to write the algorithms?

I'm not trying to shoot down this idea, it's a good one, just make sure the OP knows what he's getting into.
If we stay near ambient temperature for the water, there should not be any condensation. Usually condensation begins to form if you are at least 5C below ambient but this can vary a lot depending on room humidity. This is why it is a good idea to not go below ambient temp and the TEC itself can be easily insulated.
Regarding algorithms, there are many communities on the web willing to help people so I'm positive that if asked nicely in the right forum, you will get what you need.
After all we need two inputs ( for the two temp sensors) and one output (to control the relay. nothing more. the algorithm is pretty simple. Monitor both inputs and if input one (water temp) is 2C above input two (ambient temp) send signal to output. if input one's reading is 2C below input two's then stop the signal to the output. pulling interval for the inputs should be around 1 sec or 0.5 secs. Nothing too fancy.
 

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Dell used to sell as an option on their XPS 720, XPS 730 a system that's exactly what you're talking about. It was called H2C. The 720 was BTX, the 730 was ATX. Proprietary controller boards and PSU cables make it hard to adapt to other systems.
Here are a couple photos in my album.
http://www.overclock.net/forum/memb...bums-dell-xps-720-h2c-btx-hybrid-cooling.html
It only cooled to ambient because of the radiator heating issue, and condensation mentioned above.
 

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my thinking is to a take a 60 watt-100 peltier device right after the radiator sandwich in between a water block and a conventional cooler for the same CPU does not have to be the same CPU as whats in the system the idea is one side gets cold to chill the water the other side gets warm and is vented out of the case my thinking is to use a dell hood or something similar to directly vent this device and also insulating the water block would not hurt but not expecting to lose allot from that point my only worry is condensation so thinking I should insulate the tubing after the peltier device up to the CPU since not expecting the CPU block to stay bellow room temp after all of this what would be the safe temp reletive to room temp on a hot summer humid day my thinking is 10 degrees bellow room temp


and does anybody make pre insulated tubing my guess is want to avoid fiberglass and foam type insulation foam might be usable if covered with more tubing but do not want to stress the fittings a hard tubing might help with this rather it be strait runs only or tubing that resists bending enough to prevent extra pressure from the foam
The system will not work quite like that. If the peltier provides 100w of cooling then at normal flow rates the coolant will only be a fraction if a degree cooler after passing through the cooling block.
 
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