Morphing Air Conditioner into Autocascade System

[n00b 0f l337]

Yep, and both HX's were 10ft I beleive.

[Xeon th MG Pony]

Ya I noticed they where at the very top lol.

I realy like the SC12B, quiet and has a direct oil cooler making it prim for a water cooled aplication.

[gosmeyer]

Did you ever get this completed?

[n00b 0f l337]

Ya its all done in the first post

[mytekcontrols]

Did you ever get this completed?

Ya its all done in the first post

Yes just like Nol said, this was completed before I even started this thread. But the 2nd version which is intended for much lower temperatures, and with a bit more CFM hasn't even been started yet. Although most all of the parts required for the build have been collected.

Gosmeyer... I know we discussed the possibility of using the 2nd version with your evaporator, but unfortunately the time frame on this project has slipped way past what was anticipated (sorry). However I hope all is going well with your endeavors, and perhaps in the future we will see something become of this mating of technologies.

[n00b 0f l337]

Sounds good Michael!
Any specs on the new unit? I'm going to get my project rolling again.

[mytekcontrols]

Hi Nol

Any specs on the new unit?

Nothing specific, but I wouldn't mind seeing -100 at 250 watts. Basically my original purpose for the project was to serve as a simulator for a Polycold add-on controller product. However starting about a week ago, an alternative idea that applies to autocascades entered my mind. Something I am eager to try out. So at this point who knows what the specs could be

Unfortunately if this new idea works, it wouldn't be something I could share on this forum, since it may be patentable.

[quintus]

Unfortunately if this new idea works, it wouldn't be something I could share on this forum, since it may be patentable.

damn

just a quick question i remember seeing the lenght of the caplines in some post of your friend cryotec. if i remember well is it there, right after the condenser or condenser and filter if u wish, a verry short cap line someting like 75cm of 0,7mm capillar? thx

[mytekcontrols]

quintus asked... is there, right after the condenser or condenser and filter if u wish, a verry short cap line something like 75cm of 0,7mm capillar?

Is what there? A captube? I don't think I fully understand your question
So let me take a stab at answering it...

In a conventional autocascade what I would call the "Auxiliary Condenser" would directly follow the "Air or Water-Cooled Condenser" (just past the liquid-line filter dryer as you mentioned above). The first captube would be feeding out of the subsequent "Phase Separator". If an expansion tank is utilized, then a very small captube such as .026" I.D. would also be present, in order to slowly feed the additional refrigerant into the suction side of the compressor as the system temperatures are pulling down. Thereby preventing high discharge pressures when the unit is warm, and first started up.

The first captube would not necessarily be short (depends on I.D. used), but would be sized for a larger flow-rate then any of the downstream captubes (as much as 40-50% additional flow).

I have attached a diagram representing the first half of my next build, which gives a good look at what I have just talked about. The color Blue = Suction-Side piping, and Red = Discharge piping.

Edit: Replaced image with a higher resolution version

[quintus]

here it is:http://www.xtremesystems.org/forums/...&postcount=334

i think i'm a bit tired so here i go mumbling: what is: '' sub = 30" x .026 '' ?
i thought it was a capline to ensure that that r123 becomes liquid but i guess i'm wrong because it will evaporate then in the subcooler wich is kind of nonsens
capillar=cap line! here in some european countrys

thank you,
q

[n00b 0f l337]

The r123 and next stage gas will both be liquid, the liquid r123 is an incredible sponge tho to absorb even lower staged gases and lower its boiling point.
All about solutation

[mytekcontrols]

quintus stated... here it is:http://www.xtremesystems.org/forums/...&postcount=334

i think i'm a bit tired so here i go mumbling: what is: '' sub = 30" x .026 '' ?

It is used in conjunction with what Cryo-Tek and myself call the "sub-cooler", or perhaps better described as: the "R14 sub-cooler" which is its real purpose. This has been discussed many times before, but for a quick re-cap on the theory: The sub-cooler is intended to sub-cool the R14 liquid which passes through it, down to a temperature that some of the Argon gas is able to go into solution with the R14, thereby creating a lower boiling point condensate for later evaporation. Being isolated from the evaporator return flow, allows it to run at lower temperature then Cascade #3 that proceeds it.

edit: The sub-cooler isn't absolutely necessary for making an R-14/Argon blend work. If the load is kept relatively light, Argon can still be used. However under higher loads, the sub-cooler becomes much more important when Argon is to be used as part of the charge.

I have created a diagram which outlines the 1HP system Cryo-Tek was talking about. I have also taken the liberty of adding in the Hot-Gas defrost circuit that he briefly talked about in one of his later posts.

[Polizei]

Thinking about that copper piping tangle in that autocascade build just made me hungry for some spaghetti.

[Freddie123]

Im confused as to the use of an expansion tank on an oil line? Also do the liquid refrigerants in the phase sep join after the HX's or inside? What sort of refrigerants would you use with the R14/Argon? R123 again? What sort of ratios were you thinking for the different refrigerants?

[n00b 0f l337]

R123, R134a, R508a/b, r14+argon is done,
But r11,r12,r13,r14 is an original mix
R123, R22, R23, r14 works.

[mytekcontrols]

Im confused as to the use of an expansion tank on an oil line?

Hmm... I think you might be taking the diagram a bit too literally (so to speak). This after all is a piping schematic, and not a direct representation of the physical entity. Just as in electronics, a circuit schematic doesn't show you how to layout the physical circuitry. Instead it simply shows (in a simple way) all the electrical connections required.

Now thinking in a schematic sort of way... look carefully, and you'll see that both the oil line, and expansion tank captube are being fed into the compressor suction line. The suction line is like an electrical bus, with many connections. How this is done physically (or we could also say "in reality") is not important to the discussion thus far, although at some point it probably will factor in.

do the liquid refrigerants in the phase sep join after the HX's or inside?

As the system cools down (by passing through a given heat exchanger), refrigerant gases will condense into liquids, and collect with other refrigerants doing the same thing at each phase separation point. The gaseous portion (whatever hasn't been condensed) continues on through the next heat exchanger (hopefully to be condensed), and the collected liquids are fed via a captube to the tail end of this next heat exchanger (suction-side) and evaporated to cool.

This is a simple way of putting it, and if you scan through earlier parts of this thread you'll see it gone into with much more detail.

What sort of refrigerants would you use with the R14/Argon? R123 again? What sort of ratios were you thinking for the different refrigerants? What sort of ratios were you thinking for the different refrigerants?

Too much to cover all at once, and most of this has already been discussed through out this thread. Please review this entire thread back to the beginning, as well as any of the other threads on this forum that also discuss autocascades. I am sorry to not be more specific, but a lot of time has already been spent by me, and others going over these very same questions. Almost everything is presently available on these forums to answer all of your questions. Whatever isn't, I will try to address when I have documented this new project, but please don't hold your breath too long in waiting, because I tend to get side-tracked, and have been known to disappear for a couple of months as I pursue personal endeavors

[jinu117]

Michael, any cryogenic book in particular you can recommend? I've bought 4 and reading through 3rd one at the moment. One was total waste of money.... 2nd one had some good info which doesn't relate to what we do here... 3rd one seems a little closer so far but no cigar yet. Since these books are not cheap (eeek), I wouldn't mind getting some good recommendation

[mytekcontrols]

Michael, any cryogenic book in particular you can recommend?

Jinu there is nothing that I know of. Most of my learning has come from knowledge passed down to me from others in the field (specifically Dale Missimer to name one), and many hours of experimentation. As some have probably heard me mention before, much of what I know in reference to autocascades, is based on empirical data. And this data was often times obtained by personally trying out some idea that just popped into my head, and then seeing where it led me.

I think at some point in the near future a good book could be written on the subject, by gathering together all that has been discussed on this forum about autocascades. If nothing else, this book would at least be good for the person starting out, covering the basics without overwhelming them in the process.

[[XC] gomeler]

Hot damn Michael, this is such an inspiring thread. Wish I had the ability to work with all those gases, oh the things that could be created.

[boshuter]

The r123 and next stage gas will both be liquid, the liquid r123 is an incredible sponge tho to absorb even lower staged gases and lower its boiling point.
All about solutation

"solutation"..... are you making up words again

[Freddie123]

Im torn between solubility and salutation

[Freddie123]

Mytek can't find cryo's post on the hot gas defrost feature. Am I right in thinking that it allows a continuous stream of hot gas into the evaporator as it runs? Why is a having a none icy evap useful surely it will just raise temps?

[boshuter]

Mytek can't find cryo's post on the hot gas defrost feature. Am I right in thinking that it allows a continuous stream of hot gas into the evaporator as it runs? Why is a having a none icy evap useful surely it will just raise temps?

I have a chiller with a hot gas bypass system, mine is controlled by a solenoid hooked to a temp controller; it opens and closes the solenoid to maintain the correct temp. There is a "T" right after the condenser on mine, one branch goes to the filter/cap tube and the other goes to the hot gas bypass regulator, the solenoid is after the "T" and right before the filter/cap tube; When the solenoid is closed the hot gas goes through the hot gas bypass regulator and into the evap. It's a very effective way to control evap temps without having to cycle the compressor on and off.

[jinu117]

In this case I think the original purpose was to... thaw evap off in hurry
Basically, something of this nature takes an hour or so to evaporator to get to safe temp to remove from CPU This can be done in mere seconds this way.
Also, I am thinking this could be useful for those situations where there is possible oil frosting with some sort of control logic or pressure sensors...

[mytekcontrols]

Jinu's answer is correct. It's just an option, that allows you to bring the evap (and refrigerant line) back up to room temperature very quickly.

Boshuter also brings up a very good alternative use, that being temperature control. Although most of you guys just want to get things as cold as possible, so temperature control is probably not an issue.

Edit: Happy Thanksgiving to all that celebrate this holiday!