sub $45 Homemade chiller

[dr_dx]

What struck me funny was all of the effort and associated difficulties that go into trying to run as cold as possible. Special fluids, insulate everything, noisy, expensive, limited options, etc.

Why not find a cooling solution that would be:

Quiet - don't want to have to hear a compressor or a bunch of noisy fans
Sub-ambient - otherwise why bother with water cooling at all
Above dew point - don't want to have to insulate anything
High capacity - be able cool anything you throw at it. Needs to be able to "keep up" with the heat load.
Auto adapting - auto adapts to varying heat loads

Well here's my $43.82 solution:

5300 BTU window ac unit - $26.99 ebay
22 quart styrofoam ice chest - $5.88 Walmart
20' 3/8"x1/2" vinyl tubing - $6.99 Home Depot
4 gallons distilled water - $3.96 Walmart




Here it is laid out on my desk running and keeping my w3680 at a nice brisk 16c idle and max 50c (individual core temp) when running 20 passes of Linx @ 4.5Ghz.




Here is the inside showing the lines, evap, and the temp probe that keeps the water at the set temp. The suction line is the one by the evaporator. I use a DDC-3.25 pump (in next picture) which has enough flow (4-5 g/m thru CPU and mb blocks) to keep the water circulating very well. The inside is large enough to run an aquarium submersible style pump if that is what you want to do. The only negative was the handles that penetrated the wall. If they weren't there, I could have 4~4.5 gallons of water total and make it even more efficient. Speaking of efficiency, the extra cut outs are for ventilation




Here you can see my DDC-3.25 sitting on the desk. This is just a temporary setup until I mount the ac unit in the window behind it, after that I will make things more permanent and use 1/8" wall tubing for better thermal insulation.


In econo mode, with 3.5 gallons of chilled water @ 15c, the compressor only has to come on every 10 minutes or so, run for about 60 seconds and then shuts off. When I am doing max burns and stability testing, it comes on more frequently. Once I mount it in the window, the noise and what little heat there is will be outside, and I can use the remote to turn it on and off.

I realize this isn't for everyone, but I figured I would give another option to those folks looking at a chilled water solution.


Here is an update to my chiller setup.





















As you can see I got rid of the styrofaom and went with a 24 quart Rubbermaid. I also added a filter for the supply line (bottom opening taped off) and some edge sealing/fin protection for the evaporator. This forces the water to go through it, not around it. Now all I have left to do is mount the ac unit in the window - which hopefully will get done in the next couple of weeks - to get the heat and noise outside.

To address some earlier comments:

Someone called it a slush box - a better term would be a high power water cooler. The coldest it gets is 60F - the limit of the ac unit.

Even though humidity may change outside, inside it is always low as long as you use HVAC for cooling and you don't open the windows. So no dew forms, even at 60F. Some condensate will form on the lines going to the evap when the compressor is running, but not much - and it quickly goes away when it stops.

Yes those are aluminum fins and no, I have no copper in my loop. My EK Supreme HF Gold is gold plated inside and the factory Gigabyte mb block (UD7) is aluminum. But as was mentioned, the evap has Copper, Aluminum, and Lead solder, so I do use a corrosion inhibitor. I picked up a 12oz. bottle of Redline's Water Wetter from AutoZone and used half of it (6 oz.). I recommend no more than 2oz/gal, otherwise it will clog up the filter. I see it sold as an anti-algae solution from Asetek. It has less than half the surface tension of water (better heat conductivity), is a corrosion inhibitor for a lot of different metals (among them Aluminum, Copper, and Lead solder), lubricates pump seals, and works with straight distilled water. You can read up on all of the benefits it has here:

http://www.redlineoil.com/content/fi...ech%20Info.pdf

You don't want to use an antifreeze/coolant or anything that increases the specific gravity of your water - this will reduce flow, add wear and tear to your pump, and lower your cooling capacity.

You can see from the pics that the DDC-3.25 really pumps out some water - I would guess 2-2.5 gallons a minute. I was a little concerned since this is an open loop setup. Capacity is 3.75 gallons so it gets completely turned over in 2 minutes (good flow rate through evap).

This is just temporary until I get the unit mounted, then I will run all new 1/8" wall lines.

The best thing about this setup is the cost - less than $85 - and it gets the heat and noise outside where it belongs.




A picture is worth a thousand words... so here are a few thousand

You can see the temps here at idle and load. BTW, all throttling has been disabled so the cpu is running full voltage/clock at idle. Also notice Linx GFlops is at 100 or better on all 3 runs - so no loose, slow memory to aid low cpu voltage.















Here is a 1 year update to my original post:













As you can see I have mounted my AC unit in the window, changed lines to 1/8" wall, insulated the runs to and from my PC.

Single loop cooling of my CPU, motherboard and 2 ASUS 6970's






2 Year Update

I have switched mobo to an Asus MVF running a i7-3770K using a Ek Supremacy wb and the factory mobo chipset block. Here are the results:

Daily Driver




5Ghz LinX club submission




5.5Ghz 32M super Pi





As you can see, the chiller is still working great and allows me to overclock my IB, which is very difficult to do.




By design, high pressure, high flow, high volume, temperature controlled 60~75F chilled water

NOTE: no condensation, no motherboard insulation, no constant running (cycles just like a normal AC unit would), no radiators, no fans, and no HEAT

Total cost of all items (including wood for AC mount) minus pump, res, water blocks, and fittings = <$100

[Big Lar]

I'm running just about the same setup but with an Iwaki MD20rlt pump and a Temp controller. I have about 6 gallons of fluid and run my temp at 55 to 58f with no insulation. Works nice, great setup.

Larry

[Q56_Monster]

looking good dr dx

Now you just have to exercise some self-control.....cause, you know....you're gonna wanna go colder now

[Vampiyer]

Nice setup.

After this winter, I plan to use an A/C for my room. I don't want it to be noisy, so I decided that instead of running it as a Window A/C, I'll convert it into a mini-split, and house the compressor outside, running an insulated line to the evaporator, which will be inside the room.

At that point, I can either run air through the evaporator and duct that to my PC-radiator, or simply CHILL a Quick-Disconnect water reservoir with it.

If I chill my PC water loop, then the radiator will act as a secondary evaporator. The air through the radiator will be chilled, and that air will decrease the case ambient air temperature, and disperse into the room as intended, fulfilling the original purpose of the A/C.

If I disconnect the reservoir (using Koolance QD's), then the radiator will still function as part of a normal ambient cooling loop.

Some insulation will be needed, but if the case air is close enough to the radiator's temperature, then it'll be manageable (I've worked with phase-change before). I think I can come up with some creative solution for this.

The heat from the PC-water loop will be directly absorbed by the A/C, and most of the noise will be outside. The A/C's cooling capacity should still be used effectively assuming minimal losses to insulation. I have an electronic temperature control solution in mind - this is going to be used to cool the ROOM and the water, so I'll need to come up with a well-balanced plan.

Anyway - that is a lot of work to get in-room A/C, but I can't find much fault in it other than a major PITA if I want to move the setup to a different room. I'll choose a 5-6K BTU A/C with a high EER (11.0 or higher)... so far I've found that Frigidaire makes one for about $150.

I think it will work fine, especially because I don't intend to run subzero temperatures (I still want to run distilled water + silver coil).

I hope that gave you (or anyone) some ideas.

[Utnorris]

Don't forget, since the evap has aluminum fins on copper piping you should use some sort of anti-freeze to prevent corrosion from happening from mixing those two metals. Just needs to be like a 20/80 mix or 15/85 mix and you shouldn't have any issues.

[terramir]

Holy Crp, I am working on a pelt solution that does about the same thing (but colder, (I dun mind insulating), but yeah mod-ding an AC to cool my computer and my room would be cool ,
but yeah you should find a different styrofoam box to put that thing in then you could probably make it run only every 20 minutes or so. and well If you somehow could use a pic processor (there cheap, and with like 2 temp probes) to steer this thing a bit more refined you should be able to get away if you like a little colder water, if you use fuel/heater hose instead of vinyl hose ones, (there dual layer like a buck twenty a foot and will give you a little room in the condensation department.
good luck
terramir

[terramir]

hey where is the temp sensor the ac uses? cause this evaporator can get far colder than 60C just warning you, 60C is the room temp but the evaporator can go below freezing if it dun know better, if you mount this in the window and the temp sensor is outside your box it might just freeze the water and keep running LOL. those sensors are usually checking the air temp and if it's let's say 72C in your apartment and the sensor is outside the cooler it would keep going and going LOL.
hmmm dual cascase ac and the pelts, I'd need 30% ethylene glycol 50% plus isopropyl and 30% water hmm let's see - 30C anyone :P probably could get it colder than dry ice, if I had a clue what cooling mix to use.
Also a hint if you wired the temp sensor in there you could put it right above the water level air is an insulator and get the water colder that way However you'll have to play around how far above the water you will go and look at the temps, put a thermometer in the water and play around.
good luck
terramir

[dr_dx]

hey where is the temp sensor the ac uses? cause this evaporator can get far colder than 60C just warning you, 60C is the room temp but the evaporator can go below freezing if it dun know better, if you mount this in the window and the temp sensor is outside your box it might just freeze the water and keep running LOL. those sensors are usually checking the air temp and if it's let's say 72C in your apartment and the sensor is outside the cooler it would keep going and going LOL.
hmmm dual cascase ac and the pelts, I'd need 30% ethylene glycol 50% plus isopropyl and 30% water hmm let's see - 30C anyone :P probably could get it colder than dry ice, if I had a clue what cooling mix to use.
Also a hint if you wired the temp sensor in there you could put it right above the water level air is an insulator and get the water colder that way However you'll have to play around how far above the water you will go and look at the temps, put a thermometer in the water and play around.
good luck
terramir

Terramir...

The temp probe is the black wire coming in from the corner in the pics. It is the original ac temp probe. When you pull apart the ac unit you will see it attached to the evap fins. I drilled the hole at a downward angle so the probe extends down into the water.

I realize the evap can go much colder, but you are missing the point - I don't want to go colder.

I don't want to have to insulate anything - motherboard, lines, etc. Since I never go below the dew point, I don't have to - there is NO condensation. By not insulating the supply line, I might lose 1c, no big deal. With no bulky foam insulation, I can run the lines out of sight behind the desk from the cooler over to the back of my Antec 1200 which has water-cooling passthrus built into it.

If the water temp is 60F (16c) and I have an indoor relative humidity level of 50% (much less with colder outside temps), my dew point is 42F (<6c). Trust me, I am not getting anywhere close to 42F (6c).

Since my temp probe is on the return side, it is keeping the return water temp at the set temp. By not insulating the return line, it will make the water colder. If I add more blocks (GPU, etc.) = more heat load, it will make the water colder.

I don't want to have to use anti-freeze, alcohol, special TIM, or anything else other than distilled water and a corrosion inhibitor.

When I mount this in the window, it will be in the same physical configuration, except 3/4ths of the ac unit will be sticking outside (like normal) and the cooler will be sitting on the desk in front of it. At that point, I'll change the lines out to 1/8" wall (mostly so I can make tighter bends without kinking) and then I should be done.

dr_dx

[hillywav]

glorious dr_dx, glorious

this trhead makes want to jump from normal water cooling to water chiller... any newbs trips for going to waterchiller except for 'dew point' things and mixed metal problems?

[dr_dx]

glorious dr_dx, glorious

this trhead makes want to jump from normal water cooling to water chiller... any newbs trips for going to waterchiller except for 'dew point' things and mixed metal problems?

Nothing that I haven't covered. Pulling the evap out of the ac unit is not for the faint of heart. The ac needs to be pretty well disassembled so you have room to very, very slowly straighten the 2 copper lines going to the evap. You will probably oval some of the lines when you unbend them; as long as it isn't too severe, it's not a problem. Be careful when you are bending the lines to not kink them; if you have access to a tubing bender it might be useful. Again, a small kink isn't a problem. Sometimes a flaring tool clamp can be used to "re-round" the line. It is under pressure, so be careful. Once it is pulled out, the lines can be routed back in their original location and the ac unit re-assembled so you can mount it in a window, if that is what you want.

In my case, it is really important to "filter" the water, my Supreme HF uses the P1 (most restrictive) plate and has 49 micro channels cut in the base and any kind of debris will get caught in it. The lead solder on the evap had started to oxidize before I put the water wetter in (I ran it for a couple of weeks with just straight water), so when I did that, the oxidation started to flake off and is now in the bottom of the cooler. If you put it in at the start, you won't have that problem. The filter does a good job of keeping contaminants out of the pump and blocks.

Good Luck!

[hillywav]

yeah.. now what i need is looking for cheap ac unit in auckland(and it's going to be annoying)

just to make sure, if i can avoid corrosion via anti-freeze, will it prevent the oxidation?

[dr_dx]

yeah.. now what i need is looking for cheap ac unit in auckland(and it's going to be annoying)

just to make sure, if i can avoid corrosion via anti-freeze, will it prevent the oxidation?

I don't know for sure. My understanding is that anti-freeze does nothing for corrosion. Most coolant/anti-freeze comes with a SCA package - it is the "supplemental coolant additives" that actually inhibit corrosion. All that the anti-freeze (usually some form of glycol) does is increase the specific gravity of the water and make it freeze at a lower temp/ boil at a higher temp.

You are better off just using a corrosion inhibitor. I used the Water Wetter but there are other options, such as a SCA additive. Several companies make them - a couple that I looked at were DCA4 and ES Optimix by Fleetguard.

Here is some info:

http://www.fleetguard.com/pdfs/produ...LI33030-GB.pdf

http://www.fleetguard.com/pdfs/produ..._TB03-05-2.pdf

http://www.terrabond.net/Files/Menus/ESOptimaxEG.pdf

I am sure there are anti-corrosion additives designed for cooling towers and chillers - I just haven't had the time to study up on it.

If you run across something that looks promising, let me know. Supposedly Molybdate is the best corrosion inhibitor for aluminum.

Dr_DX

[Plan.B]

Nice job. Making me want to go to Sears and get another window A/C unit.

[Utnorris]

Looks good. And yeah the anti-freeze should act as an anti-corrosive agent. I did something similiar to this about two years back, it still has the same anti-freeze solution I started with in it and still no corrosion even though it's sitting in my garage right now. I am debating on building a new one using some of the lessons I learned from my first one or making adjustments to my current one. One of the things I was told to do back then was to take the aluminum fins off the evap, I never did, but I was told it would help with circulation and cut down on ice forming. Here is a link to my build log I did to give you an idea of what I did:

http://forums.extremeoverclocking.co...hlight=chiller

Pic of the final unit:





http://img516.imageshack.us/i/img1716.jpg/

I haven't used it in awhile, but I don't want to get rid of it since it was my first chiller.

[NEOAethyr]

That's a really nice ac unit for so cheap.
Looks like getting a phase setup could possibly be cheaper then spending a bunch of money on custom water cooling.

I'll have to do some research on replacing an evaporator of an ac unit.

A big eye opener to me.
I didn't think you could buy a nice digital ac like that for under $80.

[Utnorris]

If you don't mind insulating your board, an AC chiller can be cheap and very effective compared to water cooling. The way the OP has done it he is dumping the heat outside, one of the things I want to correct on mine. Also, if you replace the fan on the condensor side you can make these chiller pretty quiet even running constantly.

[Callsign_Vega]

Man, this thread has given me a crap load of ideas. I could use the window AC unit to dump my PC's heat out the window in the summer and I could remove the AC unit from the window and dump the heat in the house in the winter. Both ways cooling the computer down real nice. Brilliant. Time to buy some components.

[[XC] Synthetickiller]

As a guy who's never gone past basic water cooling, I have one question.

Can anyone estimate the operational cost of this?

Is live to do this for just a single CPU. If cost is low, Awesome. I know starting and stopping a compressor pulls a lot of current.

[dr_dx]

Here is a 1 year update to my original post:










As you can see I have mounted my AC unit in the window, changed lines to 1/8" wall, insulated the runs to and from my PC.

Single loop cooling of my CPU, motherboard and 2 ASUS 6970's

By design, high pressure, high flow, high volume, temperature controlled 60~75F chilled water

NOTE: no condensation, no motherboard insulation, no constant running (cycles just like a normal AC unit would), no radiators, no fans, and no HEAT

Total cost of all items (including wood for AC mount) minus pump, res, water blocks, and fittings = <$100

[eBoy0]

When I constructed something similar, the stupid thing rattled like crazy! Though, considering I was like 15 when I did it, if I were to redo it I'd probably do something similar to your setup, try a foam reservoir(although I'd be a little worried about puncturing it) and control the cycling of the A/C, as mine didn't seem to cycle, don't remember why, maybe I didn't dunk the temp probe into the coolant or something. But it was a great learning experience for me, as I did get it down to about, -30c which for a 15 year old was pretty decent.
Must have missed it, Utnorris your unit looks just like mine did! Lol, except much more professional! Did you run the rig for long?

[dr_dx]

When I constructed something similar, the stupid thing rattled like crazy! Though, considering I was like 15 when I did it, if I were to redo it I'd probably do something similar to your setup, try a foam reservoir(although I'd be a little worried about puncturing it) and control the cycling of the A/C, as mine didn't seem to cycle, don't remember why, maybe I didn't dunk the temp probe into the coolant or something. But it was a great learning experience for me, as I did get it down to about, -30c which for a 15 year old was pretty decent.
Must have missed it, Utnorris your unit looks just like mine did! Lol, except much more professional! Did you run the rig for long?

Other than using a AC unit and a cooler, what you and Utnorris made is totally different from what I made. Both of you went sub dew point and, in your case at least, sub zero. That requires motherboard insulation, anti-freeze, etc. All the things that I said I did't want to do in my original post.

[eBoy0]

Other than using a AC unit and a cooler, what you and Utnorris made is totally different from what I made. Both of you went sub dew point and, in your case at least, sub zero. That requires motherboard insulation, anti-freeze, etc. All the things that I said I did't want to do in my original post.

Right, right, but what I'm saying, if I were to redo it I'd go with your method w/ the cycling and temp control because the insulation and constant rattling was driving me nuts! Try insulating an SLI setup of old DD maze4, it's damn near impossible to get a perfect seal.

[Stewie007]

Right, right, but what I'm saying, if I were to redo it I'd go with your method w/ the cycling and temp control because the insulation and constant rattling was driving me nuts! Try insulating an SLI setup of old DD maze4, it's damn near impossible to get a perfect seal.

Ahh, its never impossible. Just requires attention to detail and patience.

[dr_dx]

bump for new additions in first post.

[Utnorris]

Just to be clear on my unit it has a temp controller, so I could set it a degree or to above dew point and not worry about condensation. The controller was the most expensive part at $55, but in total it was less than $150 to do mine. And yes, it still runs. I fire it up every now and then for old times sake. One of these days I will get back into it. Chillers are awesome, especially if you can do it like yours where you mount it in the window.