A/C to Chiller conversion

[Drewmeister]

The 3/4hp SPST switch is all you need. The low speed fan is usually overkill on these a/c chillers. If you ever want to quiet it down then put a ceiling fan speed controller on the high speed winding. Note that those are SCR and not dimmer. Your powewr cord will provide the overcurrent protection so no fuse needed.

Glad to help out.
Looking forward to the pics!

[robthered]

Hey Drew,

Your instructions and diagram worked like a charm . Thanks a ton! The a/c is up and running just as I want it.

I was going to post some pictures, but I think my girlfriend took the camera cause I can't find it. As soon as it turns up I'll post some pics .

cheers again Drew, you were a great help

[jhall.tech]

i am a hvac and refer. technician and i own a hvac company, i dont know much about computers and software i am here hoping to learn , however this thread gets my blood pumping b/c i can help with ANY heating or cooling system you are planning or modding........... please dont be afraid to ask i work on all cooling systems from large chillers to the smallest window units and refers................. i can help if you need it JUST ASK!!!!!!!!!!

[PhoenixDance]

I found a good way to cool your pc when useing normal Wcing and have an AC unit...

Duct its Cool air output into the rad and wahay! drops my temps by 18c :P

[technogiant]

Hi all, I'm trying to find a nice chiller...found this one but it uses refrigerant R410a.....not sure if it is any good for low temps.

http://www.acehardwaresuperstore.com...ners/1169.html

Drewmeister recommended 407 0r 404a but this one is a lot cheaper.....is it any good?

****...just saw its 115volt...I'm in the UK....still just in case I find something else with r410a I'd still like to know.

[Justsilent]

I know I'm completely in the wrong place for what I'm looking for as far as to what were using the system for but the system it's self is similar. I'm completely new to all this except for what I've read on this forum and another forum That drewmeister did on this site. Reason y I'm asking here instead of elsewhere is due to the fact that there are a lot of professionals on this site that could possibly help. Is it possible to place a dehumidifier or ac evap coil inside an insulated box filled with water also with walls to maximize coil/water contact constantly circulating into a 50 gal resivor what temps would I be looking at? I'm guessing an ac would work better due to the fact that you could get a bigger copacity ac say maybe 8000btu or 10000?

[Drewmeister]

Originally Posted by PhoenixDance

I found a good way to cool your pc when useing normal Wcing and have an AC unit...

Duct its Cool air output into the rad and wahay! drops my temps by 18c :P

PD.. Yes, that's a great way to drop the liquid temps. You have to watch out for condensation though. You can avoid that by routing some of the cold air into the case. Basically keep the inside of the case the same temp as the liquid so condensation can't form.

Originally Posted by technogiant

Hi all, I'm trying to find a nice chiller...found this one but it uses refrigerant R410a.....not sure if it is any good for low temps.

http://www.acehardwaresuperstore.com...ners/1169.html

Drewmeister recommended 407 0r 404a but this one is a lot cheaper.....is it any good?

****...just saw its 115volt...I'm in the UK....still just in case I find something else with r410a I'd still like to know.

TG.. Yes.. r410a will work, r407c is preferred though, especially with the larger units.

Originally Posted by Justsilent

I know I'm completely in the wrong place for what I'm looking for as far as to what were using the system for but the system it's self is similar. I'm completely new to all this except for what I've read on this forum and another forum That drewmeister did on this site. Reason y I'm asking here instead of elsewhere is due to the fact that there are a lot of professionals on this site that could possibly help. Is it possible to place a dehumidifier or ac evap coil inside an insulated box filled with water also with walls to maximize coil/water contact constantly circulating into a 50 gal resivor what temps would I be looking at? I'm guessing an ac would work better due to the fact that you could get a bigger copacity ac say maybe 8000btu or 10000?

Hello JS.. welcome to EOCF!

Yes, you would be using an a/c as it has much more capacity than a dehumidifier. The unit will need a more efficient heat exchange for quicker pulldown of the 50gal reservoir. You want to make the finned evap more into a liquid heat exchanger. Do this by adding walls in a way to force the liquid directly through the evap fins. That can be front to back.. or better yet, top to bottom.

The amount of cooling needed will depend on many factors like.. rate of pulldown needed(degrees F /hr), heat load, type and thickness of insulation, dimensions of reservoir, ambient air temp, indoors?

[Justsilent]

First of all thank you very much for taking the time to help me out. It's an indoor room cooled by cental air at 75f with a 10 x5x8 room built inside. Insulation is yet to be determined as this project is in its planning stages. But either Owens Corning EcoTouch R19 Kraft 6-1/4 in. x 15 in. x 93 in. Batts in Bag Insulation or the r13 version. All the equipment inside has a total constant heat load of 8000btu to 10000btu. The rezivor is one of them 50 gal plastic blue drums. I'm going to try and run with one 50 gal Rez but maybe have to upgrade in the future to 100gal. But for now it's 50 gal. Without the equipment running the inside room stays at 75f with the help of intake/exhaust to the lung room. As for the rate of pull down I'm not sure what your talking about. Please excuse my lack of experience. my question is what size ac should I get to chill that water. Say 20f. The chilled water is pumped through water to air heat exchangers which are put in ducting carrying all the equipments heat. thus cooling the air to maintain temps.

[Drewmeister]

Ok.. so a continuous load of 8-10k btu with approx 55F supply. A 12k btu would be enough at 8k btu load but marginal at 10k, it would have to be very well modded. I think you're going to need 14k btu.. especially when upgrading the tank. You could also go with two smaller units. Best to go with a dedicated pump for the chiller, then add your pump/s to supply the remote heat exchangers.

[Justsilent]

So no matter what I can't get those temps lower than 55f without the use of a real water chiller? Because in order for that cooled water to cool effectively the specs on the heat exchangers say approx 10f cooler water than ambient temp would cool 2kbtu. I would prefer two smaller units rather than a larger one gives me more control over everything. So maybe 2 8000btu ac or 2 10000 btu?And yes the cooling system itself is going to have a pump dedicated only to circulate the water though the evap coil and back to the Rez.
Once again thank you ery much mrdrewmeister.

[Drewmeister]

You can get the temperature as cold as you want, you just need a properly sized and designed unit. The capacity of a compressor decreases with temperature. Air conditioners are designed to deliver max performance at a higher temp range. The drop off in capacity will be greater at low temp vs a purpose built chiller. You'll be needing to oversize the a/c's quite a bit to make up for the inefficiencies.

Another important factor to consider is the condensing temp range. Due to the size of the heat load I'm assuming the a/c's condenser will be located outside. You can lose capacity with too high as well as too low of condensing temp. The unit must be sized and designed to handle this range.

If you're going to build a DIY evap in res type unit then go with 2 x 10k btu a/c's. Run them off a dual stage thermostat capable of alternating the cycles.

Keep in mind that there's some risk of getting an a/c that is either very difficult or impossible to mod into a DIY(evap in reservoir)chiller. All a/c's can be modded with plate heat exchanger and txv though. A fully modded 12k btu may work out for you. I've done quite a few of these if you need help.

[skyguynca]

I know this may have been asked before but thru the search function I can not find the answer.

I am building the a/c chiller to cool my cpu and gpu.

Is it possible to just submerge the mobo in mineral oil to prevent the condensation instead of having to seal up the mobo?

I would insulate the coolant lines to prevent much loss because of the warmer oil, also keep the lines really short where they pass thru the oil.

Wouldn't this work?

Thanks
David

[Drewmeister]

Hello Dave,

Yes, that's an excellent way to go about using oil submersion and should work just fine as long as you can also keep all the vrm's cool. The idea has been kicked around many times but no one has actually started a thread on it yet. You can find some discussions on it over in the Phase Change Section. The trick to finding the info is to search (Mineral Oil) and make sure to select (Show Posts).

Another option you might want to consider for avoiding condensate proofing is to construct an airtight chillbox to house the mobo. There are a couple of these builds in progress atm. Here are the links. technogiant's build orthello77's build

Welcome to EOCF!

Drew

[skyguynca]

Great, thanks for the info and links!!!!!!!!!!!!!!

David

[marjamar]

Just found this thread and will read it fully as I have time. I have been working on an air conditioning scheme of my own for the past couple of weeks. I have the basic setup working and am in the process of analyzing this current setup.

Using a stock Noctura D12 air cooler, I have found this current design is at least 5 to 8 C. Cooler then it was using a H80 water cooler and 210 CFM turbin fan, with no AC. I wanted to do the first set of test using this Noctura cooler because it was simply unusable in this system, even without overclocking before trying it with AC.

I'm running a FX-8150 at 4.8GHz on a Crosshair IV Extreme M/B. With the H80 and no AC, I could run Prime95 for about 20 minutes before it would reach 68C. (my max operating temp) in 74 F. ambient air. It would continue to rise to BSOD at about 79 C. if left to run. This current AC setup is running Prime95 for almost 30 minutes before reaching 64 C. temp, and will slowly rise to about 68 C, max.

All my components are under air. They are in a temporarily fabricated enclosure that contains the air conditioner in an enclosed compartment, with the computer above it in another compartment. I am working on adjusting the recycled amount of air v. the amount discarded through the compressor compartment to aid in cooling the air conditioner components and lowering the discharge air though the condenser. Since I do not plan to vent this unit to any exterior, I need to find the most ideal means to keep heated discharged air to a minimum and at as low a volume amount as is practical.

I'm wondering if anyone else is doing this or not. It seems to work as I've managed to keep the entire computer system at a static temp of about 35 F. under minimal load. Under extreme load, it rises to 41 F. The discharge air temp is 98 F. normal load and about 102 F. under full processing load. My CPU temp under normal load stays less then 20 C. and most components temperatures are less then 30 C., including the GPU (Geforce GTX 470).

As I said, I've yet to read this post, so I think I'll read a bit now.

I'll post back anything I may have questions on after I do some reading first.

Thanks for doing this thread.

-Rodger

[Drewmeister]

Hello Rodger,

There are quite a few ppl who have run chilled air including myself. Yes.. it definitely works great and is relatively simple and inexpensive to set up. Switching to chilled liquid will greatly increase the oc potential of your hardware while reducing the heat dump and noise levels in your room.

Keep in mind that with todays hardware, load temps with 32F/0c air are not going to be that much better than from a quality ambient water cooled system. The cooling power of the a/c can be put to much better use as a liquid chiller. A chiller can be run at warmer temps via a thermostat. 0c is very easy to insulate for and will max out just about any gpu short of hard volt mods. The FX's scale well with temps so the colder the better.

Go ahead and have a read.. I'll be around if you have any questions.

Welcome aboard!

-Drew

[marjamar]

Thanks for the reply Drew.

I've no doubt chilled liquid would promote overclocking far better, but unless I have a fully dry environment for my computer to work in, dew point will obviously be exceeded and moisture/frost will be a problem I'd have to deal with. As a sandblasting and coatings applications contractor, I am very familiar with humidity, temperature and dew point and their effects on things. I would imagine there's ways to keep dew point 5 degrees F. above air temps, but that would involve creating a workable environment as well. If I were to do this, I would make a hermetically sealed enclosure for the motherboard (at a minimum) and evacuate it as I flush it with nitrogen gas to a bit higher then relative air pressure.

That sounds like alot of work to me.

I'm sure there are other "tricks" that people do, but I was more leaning toward something along the lines of a more or less "plug & play" case type of thing, where most anyone would be able to take advantage of a cold air environment for their whole computer system to be installed in.

On the hacked together rig I've come up with, I've exceeded my best overclock by .5GHz so far. I'm sure, once I get a custom water cooler setup, I'll get maybe another .5GHz or maybe more out of it.

I think for alot of people, this would be appealing and worthwhile enough to want to do it. Let's face it, 5.8GHz or 4.8GHz isn't really going to may any difference in most peoples lives on a computer, but the idea of being 20% faster then his/her buddy's rig would or at least could make a difference.

Here's my latest:



Before starting this project I was stable at 4.8GHz.

-Rodger