New build for a water chiller! 1/3Ton (1/2Ton TXV)

[XeonStrikeForce]

Well I finally got all the parts I ever needed! So now it is time to BUILD! (Please keep in mind I don’t give a squat about super low temps, I’ll be happy to hold a nice +-0C constant, in fact that is my main goal is to simply keep it at a nice cool +-0C and perhaps for fun lower if I feel the need. So please no bashing or ranting at how it won’t get Über cold, I all ready know this nor do I care!)


Here's the parts list:

- Copland R-12 Medium temp compressor
- 1/2 Ton TXV American control Company
- Sporlan 1/4SAE Flare, Solenoid Valve (NC) <Got one
- Sporlan Filter/Dryer <Got one
- Sporlan Sight Glass <Got one
- Ranco Low pressure trigger <Got one
- Home made receiver <Scored a free one and bought one


Tubing Size:

- 3/8th
- 1/4th


Evaporator:

- Helically wound 3/8th Tubing


Refrigerant:

- An Azeotropic Mix of 80/20% by Mass weight of R-134a & R-600a (This is said to out perform R-12, and is Listed as a drop in replacement) < May just use Pur R-134

History:

This all started when I found an old vending machine, before that point I was all ways interested in phase change, and I managed to pull the plant out of it, this finally gave me a chance to mess around with the idea. Well years later and TONs of learning I slowly started to collect parts and plot a killer build, well due to a good friend and some luck I got all I needed and being I run a Dual Xeon server what better project then to chill it!


OPERATION:

Obviously it will be pointless if I have to sit there and flick a switch one and off and it would all so be murder to the hydro to leave it running all the time! So how do I get it to cool well yet not short cycle or run 24/7?

The solution? Copy a large-scale systems way of doing it! not creative in of its self but very clever way to deal with the issue at hand non the less

Lets start at the solenoid valve, When the water gets too warm the thermostat makes a call to the Normally-Closed Valve telling it to open, this will allow liquid refrigerant rush into the TXV, the TXV then meters the refrigerant to the needed level to keep the evaporator at a constant temp.

This whole operation starts very fast, but wait! The compressor isn't running at this point! The thermostat only told the solenoid valve to open
this is where the low side trigger comes in, it sees the sudden rise on the low side and then tells the compressor to turn on! The system will run until the thermostat is happy again at which point it shuts of the solenoid valve and the suction vacuum will increase to the cut off point of the low side switch (This is because even though the thermostat shut of the valve, the compressor is still running).

The reason for this is better efficiency from the refrigeration system, any leaked refrigerant during the off cycle will evaporate raising suction pressure to the trigger point, at which the system will pump down and, while at it, further chill the water without needing a full out cycle and negate the need of an accumulator...


Work to do & Don:

So fare I need to build a Receiver, and to figure out final wiring. I have the low-pressure switch connected to a homemade L bracket and wired to the compressor.
The main thing on my list though is to get the compressor flushed & refilled with clean mineral oil as the old oil was beyond salvage. I have fabricated a ½ SAE Flare to 3/8th Copper solder connecter for the TXV to Evaporator mount.

My goal for now is to finish the Compressor Plant and have it fully oiled and wired and at a running state before I start making the evaporator. Aside from needing a couple things, yet to arrive, in the mail this is nearly complete unless I should need to replace the high side service valve as I fear I may well need to do!

Real picks soon to follow, but for now I nice MS-Paint on to hold you through!
http://img114.imageshack.us/my.php?image=compressorplant4kc.jpg

All items in BOLD have been updated as of Jun 6th 2006 (And satan hasn't poped up any where yet )

 

[greenmaji]

wow.. complicated..
hot gas bypass is about all Ive read about to conroll temperature, but it seems your wanting more then that, and you seem to have a soulution that I havn't heard of.
pictures of the parts would be cool
guess Ill just wait. LOL

 

[XeonStrikeForce]

Ya, I'm in the same boat! dam mail, all ways so bloody sloooooowwwwwwwwwww.

Hope fully by the seventh or tenth at the latest I aut to get the rest in!

Here's some of my new aquasitions:

 

[XeonStrikeForce]

The yello jar is filled with AlkyleBenzine Oil, I use it to clean my pipes befor flaring! so there, no weird questions

 

[Electron Chaser]

Oh this has some serious potential. Subscribed!!!

 

[ziggo0]

Oh this has some serious potential. Subscribed!!!

 

[jagbot]

I'm planing to built my own Chiled water cooling (from new part), but whit a gaz to water heat exchanger place in a relativily small reservoir/container to reduce the short cycling.

Jag.

"Edit"
Found this thread in a another forum, hope it could help.
http://forums.extremeoverclocking.com/showthread.php?t=101902

 

[-aDaM^]

Oh this has some serious potential. Subscribed!!!

 

[XeonStrikeForce]

Well I just recieved my R-22 Can tap for the R-22 can (Who would of thought!)

Sooo that leaves the solinoid Velve and coil assembly, and access velve! got the TXV converter made. Here are the pics of the actual plant I'll be using:

 

[XeonStrikeForce]

and here's the main part that does the majic. The last pic is what I use to charge my R-290 systems.

And Jag, to reduce short cycling you want a BIGGER Resavour, More thermal mass streatches out the temp curve IE More water equals slower pull down but more thermal stability, meaning your temp fluxes are totaly smoothed out and slow where as a small res temp fluxes happen very fast, thats why My res will be around five Gallons or so and I'll use some fiber insulation (Still trying to figure that one out actualy far as insulation goes)

 

[XeonStrikeForce]

http://stores.ebay.ca/Frosty-Freeze-A-C-Products-Company < Here's where I buaght the Can Tap unit from, the guy's a bloody machine, instant replies and instand feedback! the unit I got is under refrigeration and AC suplies

and even weirder is the thing arrived early!

 

[greenmaji]

I knew you were serious about this project
Do you have a sister thread over at phasechange? If so could you post it, the members there would have some killer insite.

Lets start at the solenoid valve, When the water gets too warm the thermostat makes a call to the Normally-Closed Valve telling it to open, this will allow liquid refrigerant rush into the TXV, the TXV then meters the refrigerant to the needed level to keep the evaporator at a constant temp.

This whole operation starts very fast, but wait! The compressor isn't running at this point! The thermostat only told the solenoid valve to open
this is where the low side trigger comes in, it sees the sudden rise on the low side and then tells the compressor to turn on! The system will run until the thermostat is happy again at which point it shuts of the solenoid valve and the suction vacuum will increase to the cut off point of the low side switch (This is because even though the thermostat shut of the valve, the compressor is still running).

Do you have the solenoid valve and low side trigger yet? I'd like to see a picture of the low side trigger, thats part of the project thats new to me.

good luck

 

[XeonStrikeForce]

I'll snap a close up of the low side unit for you, I pulled it off an old system any large scale system will have them.

Solinoid velve nope may be lucky! haven't checked the mail yet

FING RIGHTS! The velve came in today! just not the coil, geting closser n closser

 

[XeonStrikeForce]

And Now here is how we get R-134a without a liscance in Canada.

Take one air duster can, 10 Oz for $13 Dollars, Pull off the head cut the white tub thing so its about 3mm from the velve base on the can, attach the locking unit, thread on tap.

And now you have a nice can of R-134a ready to go!

 

[dz_jad]

rofl.
thats a good way to get-er-done!

 

[greenmaji]

HEH.. when you can figure out a way to get 507 and 116 Im all ears ROFL

 

[jagbot]

Hi Xeon, i understand about the volume of the reservoir, but would't be better a water/gaz evaporator, insted of air/gaz evaporator like the one your building. Whit water/gaz evaporator you could obtain a much lower temp then whit a air/gaz evaporator. It's just that the suction inlet of the pump would be conected to the outlet of the water/gaz evaporator. It's what a remenber from my refrigeration cours in college.It's just a tought.

Jagbot

 

[XeonStrikeForce]

what on earth are you talking about? It is a direct acting submerged evap, there is no air involved in it aside from air cooling the condencer, are talking about a water cooled condencer aswell?

That sounds like a tube in tube system, I'm not intrested in that due to the fact it requiers a much higher duty cycle, the design I'm implimenting demands a low duty cycle, other wise the compressore will live a very short life, hence why I want such larg thermal capacity as well. This will make it so the system needs only start every once in a while rather then every fiew minutes.

If you think post #3 was what I'm using No, they are just some fun toys I was recently given, I have yet to construct the evap, I'm still debating between two diferant designs, but both are direct acting to the fluid.

 

[jagbot]

The evaporator that you use is in fact a gaz to air heat exchanger that you submerge. What i'm talking about is a evaporator that made for heat exchage betewne gaz and water, dus better performace, and that type of evaporator is in itsefl a reservoir.

 

[XeonStrikeForce]

No you still dont get it, the evap I am using I am still engineering! The ones you see in the photo I have salvaged and am selling them, I am not using them, Pay close attention to what I've typed, I have said this round 4 or more times.

THE ONE I AM BUIDING (Key word is building) IS A DIRECT ACTING EVAP.

This means it does all heat transfer directly to the water, the only air in it will be microscopic bubles that are cuaght in the liquid, I can't make this any simpler or clearer, I figured saying it 4 times was enough, but I guess I was wrong. I know of tube in tube exchangers, their thermal capasity is non existant, ie they need a 100% duty cycle rather then a 50% duty cycle that I'm aiming for.

FYI I do not even have an evap built so how in the hell can I be using it? Your telling me some thing that dosn't even exist yet will not work, this not only leaves me confused but very annoyed. Please read through the posts again and pay very close atention to what it says on post three (3) and if you still miss the key word again, I'll quote it in size 89 bold font for you.