How many people here have build a phase change cooler?

[Crazy OC]

Hello fellow OverClockers

I'm just wondering how many people here have build a phase change cooler for their computer?

[WyrmMaster]

I know of one, search the forum and youl find the post on it, he has a very nice writeup of it on his homepage.

[The Overclocker]

welcome to the forums

not many, the best places are too look at era manufactures such as cryoech and vaporchill which do these thing and pinch their ideas

[ptcg]

I did! I did!!

You can check out my website for all the details/pix.

Still running great!

[Hachet]

WoW ptcg! That's great! Basically a fairly detailed how to.. Excellent stuff. :) Nice temps too.

[Crazy OC]

Hey ptcg,

I know about your site, I was doing some searching on the forum last night. you have very detail informations.

Just one question, did you charge the refrigerant under vacuum or not?

[ptcg]

yeah, I rented a vacuum pump from a local equipment rental place... Worked out nice... I forgot to put that on my site.. I'll have to add it in there.

[-=HN=- Wild9]

so basically next time i see a refrigerator sitting on the side of the raod, tear out the good stuff from the insides of it incase i ever want to try this project...

[Crazy OC]

I'll see if I can find a equipment rental place, how much does the rental cost you?

It only take you one can of R-134A to fill up the compressor? I always thought it's going to take at least 2 to fill it up.

[ptcg]

I used less than 1/2 a can of r134a... You don't want to 'fill it up'... You should put only enough in it to get it working correctly.. Remember, the more you put in it, the higher the pressure will be & the higher the boiling point (the warmer it will run).

Mine is only about 3PSI on the low side (the side returning to the compressor) while running. It's about 45PSI when off. As the pressure goes up, the temp goes up..

If you don't put enough in, it won't get cold at all, so your best bet is to add it slowly until it starts getting cold, then wait a bit & check the pressure, keep filling/checking until you get the results you want.

Depending on how you make the evaporator, you can actually regulate the running temp by the freon amount... If you make a large enough evap & get it running too cold, just add more freon to warm it up a bit...

I didn't want mine running below 0C because of condensation issues, so I made the evap smaller. Mine holds around 9C constantly at 100% load. (it drops to about 3C at idle). This is perfect for me because the CPU pins stay about 1-2C above case temp, so I don't need to worry about moisture forming at all.


The vacuum pump ran me about $30 for 1 day.. Pretty steep, but to buy one it's over $300 for a 'cheap' one, and I was only using it for 1 day anyway.

[Kurupt2001]

I got one =]

[Crazy OC]

Kurupt2001, what do you got??? A phase-change cooler???

[Maximus Nickus]

You would have to be careful if using fridge parts, as I heard that cooling a hot cpu they will only last a few weeks...:rolleyes:

[ptcg]

I made mine from a counter-top soda fountain... It's running more or less 24/7 for months now.. no problems at all....

[iggybaseball]

whats phase change coolin?

[ButcherUK]

Originally posted by iggybaseball
whats phase change coolin?

You compress a gas (usually freon) till it becomes a liquid, then pump it to an evaporator where you heat it till it evaporates (with your heat source, eg. cpu), the evaporation uses energy and therefore cools the heat source (cpu). You then have the freon (now a gas) flow back round to a compressor and compress it back into liquid.

[CreePinG_DeatH]

Two questions- Are there other refridgerants that you could use in a stand phase change setup like you have made? I don't want to be as extreme and say helium, but it would be nice heh....

Also, with compressors, will there be any advantages of using larger compressors?

[kevin_bouchard]

a bigger compressor will be extremely better, because it will be able to compress faster and higher the r134a, which will allow you to use a bigger evaporator. The only down fall is that you will probably need a bigger condenser(rad that gets hot) to cool down all that hot gas!
It would also be able cool more, but like fans and everthing else there is overkill, so saying that you dont want one that is the size of your case(if they make them). I think a good size compressor would be the size that you would find on a normal fridge(but these arent good because you cant run them 24/7)

hope this helps

[Maximus Nickus]

If freon leaks does it conduct electricity? If it don't im there! (Ie will it damage stuff)

[ptcg]

a bigger compressor will be extremely better

Bigger is not really better.... My compressor is kinda small, but it's rated at about 3000BTUs... The CPU is only putting out under 400BTUs, so it's already overkill... (BTUs=WATTS x 3.5 [about])

because it will be able to compress faster and higher the r134a, which will allow you to use a bigger evaporator

You wouldn't want to compress the refrigerant more, because the higher the pressure on it, the higher the boiling point, the higher the running temp. Besides, if you want higher pressure, you just fill it with more refrigerant. Just enough pressure to convert to liquid is what we want here.. no more, no less..

A larger evap will have more cooling power, but not so sure it is a good idea.. the larger the evap the harder it is to control condensation. My evap is only 1 1/4" x 7/8"dia. and it works fine.

I think a good size compressor would be the size that you would find on a normal fridge(but these arent good because you cant run them 24/7)

I wish everyone would stop saying this... I've spoken with several HVAC techs, and they all say the compressors are fine running 24/7 as long as they're properly cooled. Mine runs 24/7 most of the time & I've had no problems at all.

Freon (as far as I know) does not conduct electricity... It is very harmful if inhaled though.. Make sure it doesn't leak..

[CreePinG_DeatH]

So then you might be able to use a compressor like the one from a fridge, add more freon, and use a larger radiator up to a certain point correct?

[ptcg]

I would say...

1) try to get the smallest compressor you can find. Remember, you only need 400BTUs or less. (depending on the CPU, speed & voltage)

2) Make the evap as small as possible for condensation issuses.. Either this or be prepared to insulate well. (Too small won't allow for proper cooling of the CPU and compressor, so be careful) *The compressor uses the refrigerant to cool itself too - FYI*

3) The radiator (condensor) must be a single-path type.. Auto radiators/heater-cores WILL NOT WORK.. The larger the better, as it will cool the compressed refrigerant more which will lower temps overall. Also, make sure it is cooled too (fan on it, same as water-cooling)

4) How much freon depends on the a lot of things.. Compressor size, condensor size, evap size, length of capillary tube, etc... That's something you need to determine yourself through trial & error..

Oh, about the running 24/7 deal... Here's a quote from an HVAC tech...

The motors in compressors are "continous duty" motors, and rated to run all the time.

Whether that is good or bad is debatable, and I'm sure someone will be along soon to debate it.

But, here are my thoughts on the subject: Heat pump manufacturers tell us that running the unit year round instead of just in the summer makes for longer life. This tends to bear out in the field, so it would seem to be true. Evap fan motors that never cycle off last longer than the ones that do, so that would also indicate truth in the argument. Refrigerators tend to run more than HVAC compressors, and tend to last longer. So; all these thoughts have led me to conclude that a compressor is not damamged by continous run time. However, I have no conclusive data with which to backup my assumption.

[Cowboy X]

has anyone tried something like the ZEN cooler.............
@ www.plycon.com (where i saw them )

[kevin_bouchard]

ptcg thanks for correcting me!
about having more pressure I was refering to the highside only so that the gas would be moving faster through the evaporator, which would remove the heat faster(same ideal as having a faster pump in a watercooling system).
Thanks again for correcting me, I learn something every day here
:D

edit. I hear from alot of people that the zen isnt that good of a cooler,its acts like a heatpipe but with a fan.