Chiller temp controler

[Titan151]

Hi all,

I recently picked up a via aqua chiller (cc25). So far initial tinkering with this thing looks good. AquaStealth.com sells a modified version of this chiller that will easily cool (as they state) your vid card, NB, and CPU. I am pretty sure the mod they do to this unit consists of a new temp controller that allows the unit to reach near zero (C) temps. (as it is only 30 bucks more then the normal unit they sell) I took a look inside the unit and determined I could wire the compresor to stay on when ever the chiller is on. This would allow the unit to reach max cooling. My question is, when people build there own chillers do they keep them on all the time or cycle them on and off like a fridge works. The reason for concern with standard control that I have is that the unit will go up from the low set point by 5 C and then come back on and cool. Since the cpu takes a while to heat the water up it's temp might fluctuate by something like 10 or more degrees. This frequent temp change is less then desirable. That said, should i run this with the compresor on all the time or with temp control. I supose if I got an external temp controller I could wire it to keep the chiller at an operational range of 1 or 2 degrees decreasing the temp fluctuation.

Here is a link to another thread with some picks and what not.

http://forums.procooling.com/vbb/showthread.php?t=9522

[redleader]

Chillers are typically run 24/7. Cycleing them on and off frequently isn't good to do.

Good, just keep in mind 1500 BTU/hr isn't much power.

[Marci]

I tend to yoink the two wires out of the thermostat and twist em together, bypassing any temp control whatsoever making the unit run flat out at all times.

[pHaestus]

depends on what your goal is. I think that 5C water and much less electricity is a better deal than -10C water and huge electric bills. That's just me though...

[redleader]

ANyone know what the actual compressor size is on that thing? The site say 1/4 HP and 1500 BTU/hr (which is closer to 1/8th HP . . .) If its 1/8th HP, no sense switching it off. A chiller that size uses relatively little power compared to your computer, so theres no sense turning it off and possibly damaging it. If its 1/4 thats a little more substantial, but still not enough that'd you'd notice it on your electric bill unless power is really expensive where you live.

Interesting aside: an engineer showed me a refrigeration system for a growth chamber a while ago. They run the compressor 24/7 and simply heat the excess liquid refrigerant with outside air. He explained that it was cheaper to waste the power then to replace the compressor sooner from the added wear of switching it on and off.

[Titan151]

Yes it claims to be a 1/4 hp, but is rather small compared to other 1/4 hp units I have seen. I took it apart last night and am in the process of getting it set up. I finished insulating the mobo last night and this morning. Very pleased with the results. (I was a little hesitent as to if the unit would boot after all that CC, silicon, and dielectric grease.

My swifty 600 pump is insane. I just got it a week ago and finally got it installed. It's so quiet that I didn't even think it was on. It has an adhesive pad as well that makes mounting it very nice. It feels like a good solid piece of equipment. Very pleased when compared to the other pumps I have had. Not to mention the fact that it operates on DC power. I also hooked some quick connects up to my rad for my 3/4" tubing. They allow me to seal off the inlet and outlet of the rad. If I need to take the unit somwhere they will allow me to leave the chiller at home. (only using it when the chiller is not in use). I will post some picks after I get back from camping in the rain this weekend.

Oh, I also rigged up a piece of UV acrylic and placed above the vid card. This way in the event of a drop of conedensation or some kind of minor mishap It should stay relatively dry. I may also use it to create multiple air chambers inside the case. I am going to thermoform it when I get back. Anyone know the thermoforming temp window for acrylic? It's not vinyl acrylic so It doesn't degrade..(me thinks ). I may just use a heat gun as I only need to do some minor bending to get it to fit between components on the mobo.

[jhurliman]

Originally Posted by pHaestus

depends on what your goal is. I think that 5C water and much less electricity is a better deal than -10C water and huge electric bills. That's just me though...

I've been trying to figure this out all day. Are you saying a system with more cooling capacity (btu's) will be able to reach a lower temperature? It seemed to me the minimum temperature was based on the refrigerant and having a compressor+condenser+evap+capillary+etc to match it. Is one R-22 system able to reach lower temperatures than another? Because a 1500 btu/hour (439.6 watts) system would more than take care of a single PC as far as bringing it to ambient; it's the "overclocking" of phase change systems and running them cooler than they are intended to go where I have very little understanding.

[Kobuchi]

Originally Posted by Titan151

Anyone know the thermoforming temp window for acrylic?

Wide window. You can start bending it at around boiling. Easy working temperature is about 160 C (325 F). Just place it on a form and watch it droop in the oven.

[Titan151]

Originally Posted by Kobuchi

Wide window. You can start bending it at around boiling. Easy working temperature is about 160 C (325 F). Just place it on a form and watch it droop in the oven.

Heh,

Took a while to get the answer as I originally asked question in May. Regardless, thanks for the response. I was working with acrylic so I hit it with a heat gun. It's always fun stuff to work with. My only concern was if it had a degradation temp like vinyl. I remember back in a plastics class this one guy over did some vinyl and, well it was not good for the Lab or the entire building.

[redleader]

Originally Posted by jhurliman

I've been trying to figure this out all day. Are you saying a system with more cooling capacity (btu's) will be able to reach a lower temperature? It seemed to me the minimum temperature was based on the refrigerant and having a compressor+condenser+evap+capillary+etc to match it. Is one R-22 system able to reach lower temperatures than another? Because a 1500 btu/hour (439.6 watts) system would more than take care of a single PC as far as bringing it to ambient; it's the "overclocking" of phase change systems and running them cooler than they are intended to go where I have very little understanding.

The temp of the evaporator depends on the boiling temperature of the refrigerant. This can be looked up on a chart, or with a free tool like Refrigeration Utilities. In theory you can get almost as low as you want by decreaseing the low side pressure (well eventually you have perfect vaccum, but within reason). In reality though you can't do this.

What happens is as you lower the low side pressure, it gets harder and harder to get any lower because the refrigerant flow through the system has to be at a certain level to match the CPU power load. So while you can keep makeing the cap tube longer and the compressor more powerful, it becomes less and less effective because you have to push a minimum refrigerant through at all times and this prevents the vaccumm from getting very low (typically people seem to aim for around 1 atm of absolute pressure w/ R22 in direct die systems).

Thats why people cascade. You can't make the high too high otherwise you'll break the compressor, and you can't go too low or your capacity drops off real fast. So you break the system down into discreet steps each with a reasonable pressure difference.

You're right about wattage rateing. Its pretty much meaningless, except to figure out the power of the motor. And generally I think something around 1/8 to 1/3 HP is the sweet spot in terms of performance/energy bill.

I'm still collecting parts though, so I could be wrong.

[Tachyon]

jhurliman yer right about 1500 BTU/Hr being enough. A 3ghz Prescott should put out about 500-600 BTU's. (sorry can't link that figure, I've been reading too many threads of late)

[tigerhing]

Hi there,
So, if I understand the discussion about this chiller correctly, I can run this unit 24/7 without burning out the unit. The manufacturer did not recommend me to run it all the time.
Any problems with running this unit all the time?

*****
Previous message:

I recently picked up a via aqua chiller (cc25). So far initial tinkering with this thing looks good. AquaStealth.com sells a modified version of this chiller that will easily cool (as they state) your vid card, NB, and CPU. I am pretty sure the mod they do to this unit consists of a new temp controller that allows the unit to reach near zero (C) temps. (as it is only 30 bucks more then the normal unit they sell) I took a look inside the unit and determined I could wire the compresor to stay on when ever the chiller is on. This would allow the unit to reach max cooling. My question is, when people build there own chillers do they keep them on all the time or cycle them on and off like a fridge works. The reason for concern with standard control that I have is that the unit will go up from the low set point by 5 C and then come back on and cool. Since the cpu takes a while to heat the water up it's temp might fluctuate by something like 10 or more degrees. This frequent temp change is less then desirable. That said, should i run this with the compresor on all the time or with temp control. I supose if I got an external temp controller I could wire it to keep the chiller at an operational range of 1 or 2 degrees decreasing the temp fluctuation.

Here is a link to another thread with some picks and what not.

http://forums.procooling.com/vbb/showthread.php?t=9522[/quote]

[redleader]

Depends on the condensor. Its possible the part wasn't speced to handle the load from 24/7 operation. In which case the condensor would be running very hot all the time and you might eventually burn it out.

I'd touch the condensor to see just how well its handleing the load. It should be warm, but not burning. If its hot, either get a better condensor or a better fan. The compressor itself should be pretty hot to touch normally, but if its extremely hot (90-100C), you probably need some airflow around it.

[Titan151]

Hey,

Well so far I have been running this thing more or less non stop for 6 months with no problems. After tinkering with my setup a bit I got it down to about 5 degrees C, cooling a mobile 2600. My OC is around 2.7 ghz. I am more or less pleased with the performance. As I mentioned, running this thing non-stop is probably not desired, but so far so good. One of the nice things, is it is quiet and doesn't draw too much power.

[brucoman]

I've used a chiller for the last 18 months, originally an aquarium chiller, these are NOT supposed to run 24/7, they are designed to cycle around a setpoint set by a controller.

[tigerhing]

What is your power dissipation? I am dissipating about 360 Watts, but my set point is at about room temperature. I have put a circulator in line with this chiller. The temperature is maintained at 70°F.

Originally Posted by Titan151

Hey,

Well so far I have been running this thing more or less non stop for 6 months with no problems. After tinkering with my setup a bit I got it down to about 5 degrees C, cooling a mobile 2600. My OC is around 2.7 ghz. I am more or less pleased with the performance. As I mentioned, running this thing non-stop is probably not desired, but so far so good. One of the nice things, is it is quiet and doesn't draw too much power.

[tigerhing]

Originally Posted by brucoman

I've used a chiller for the last 18 months, originally an aquarium chiller, these are NOT supposed to run 24/7, they are designed to cycle around a setpoint set by a controller.

So, are you running yours continuously? or do you allow it to cycle on/off?

[redleader]

Originally Posted by brucoman

I've used a chiller for the last 18 months, originally an aquarium chiller, these are NOT supposed to run 24/7, they are designed to cycle around a setpoint set by a controller.

Why specifically? Poor oil return rate? Poor condensor cooling? These things can probably fixed without too much trouble . . .

[brucoman]

aquarium chillers do not run 24/7, they are designed for a duty cycle, not continuously

I have my setpoint at 64f in summer, 60f in winter (any lower & I get condensation on copper elbows & blocks - lost a 9800xt this spring....) I do not want to insulate anything so I do not desire it any lower - perfect for me

[redleader]

Originally Posted by brucoman

aquarium chillers do not run 24/7, they are designed for a duty cycle, not continuously

I have my setpoint at 64f in summer, 60f in winter (any lower & I get condensation on copper elbows & blocks - lost a 9800xt this spring....) I do not want to insulate anything so I do not desire it any lower - perfect for me

You already said that. I asked you (or anyone) to explain why.

[Titan151]

Originally Posted by tigerhing

What is your power dissipation? I am dissipating about 360 Watts, but my set point is at about room temperature. I have put a circulator in line with this chiller. The temperature is maintained at 70°F.

Tigerhing,

My power dissipation is not all that much. I am simply cooling a mobile XP 2600. I think at stock it puts out something like 45 watts. I have cranked up the voltage quite a bit, but still it's not that much in terms of heat load, compared to what you have. I bypassed my chiller's temp controller and run it non-stop. This keeps the temp on the CPU consistent and as low as possible. I know my chiller wasn't made to run this way, but then again, neither was my CPU. And overall, it has been running great for a good 6 months. I supose one of the nice things about running it all the time is that you never hear it come on and off, so it more or less becomes consistant background noise. My unit is also fairly quiet, similar to a small house fan.

[brucoman]

as stated before, most pre-built chillers we use are from the aquarium market.
reef aquariums need a very narrow temp window to survive, so chillers were created for this application that can comabt high intensity lights & several big arse pumps. To accomadate as many different set-ups as possible they tend to be oversized so as not to run 24/7 and cycle to a delta of 1 degree c, running outside the target temp kills things.