Building Cascade ...A Walkthrough

The exchanger maxed out on me @ -43C (after 10min of work), probably would go further but the compressor heats up very much :\


Now i need some of Gary's help with tuning up the system, all i can remember were some sst and other stuff like that temps, pressures etc., could you post these shortcuts with a little note what they mean ? ^^

I know that pressures are 200 psi on the high side, a little vacum on the low side, -43C evap temp. the line next to the compressors accumulator is if i remember between 7 and 14C, ambient is 32C and the freon leaving the condenser is ~34-35C :o Post some more info when the compressor chills a little

I think that there's a curse on me... wich always lets me come very near finishing smth. but always makes it !F!U!C!K! UP!! so it doesent work... right now one of my shrader valves simply exploded, i unscrewed my service mainfol, wanted to seal with a cap and the moment i touched it- WHAM the valve shutted out letting all the freon go out.... Makes me wanna cry.... These are one of those moments wich make you want to leave it all alone...

These are the times that try mens' Souls......

Only the strong survive.

Hang in there.


Pops.

Ill survive but the problem is the incredible rage in me... If i wont let it out ill simply pop and do smth wich i wouldnt want to do..

i know the feeling, when i was finishing up my system this summer i found out that soldering doesnt cut it so i had to go back and redo all of my joints with 15% silver brazing alloy because i had about 10 leaks! it took me a long time to do and once i was done i found out that my manifold hoses leak too. the best thing to do is take a deep breath and think of the frost forming when you get finished :)

Ok, heres smth. really interesting for ya guys: how will i connect the injector to the evap ^^

Heres my thought path:

Orings wont stand -80C for 100%... What to do ?? Thinnk, think... What about flare fittings ? :o They will be great for such temps :o Ok, now how to change an injector sa i can connect flare fittings ?.. Hmm,.. Its made of steel so its very tough and will stand much.... So lets make some flare fittings in copper, female, treat the injector as it was a double male fitting and we get smth. like this:

Even dough it looks like crap it holds pressure :o Im gonna make a better prototype tomorrow

Welcome to the wonderful world of refrigeration. I have seen grown men cry (and throw things, break things, etc).

Take a deep breath, fix things as they break, and eventually you will get there. It's man against machine. Show no fear and never let the machine beat you. :D

One system is bad enough. Two systems (cascade) can really make you crazy. So what we need to do is forget that we have a low stage. Leave it off and forget that it exists.

Once you get the high stage going again, and down to its lowest interstage temp, we need to know:

Type of refrigerant used
High side pressure
Condenser air in temp
Condenser air out temp
Liquid line temp near condenser outlet
Low side pressure
Suction line temp near interstage outlet
Suction line temp near compressor inlet

R22
200psi
27C
30C
31-32C
~10psi
~ -32C

The system was VERY overcharged:

-30C on the acumulator

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Welcome to the wonderful world of refrigeration. I have seen grown men cry (and throw things, break things, etc).

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I always was a little O_o and refrigeration used to relax me but if i cant find a damn leak i get really furious...

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Take a deep breath, fix things as they break, and eventually you will get there. It's man against machine. Show no fear and never let the machine beat you.

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It wont beat me but tomorrow i have to go with my parents on holiday (damn baltic sea) and there wont be any aftermatch tomorrow.... 2 weeks of sitting on the beach and tearing your hair of your head cause theres nothing to do.. And after all of this its payday, im buyng a new filter, a 13kg can of R22, 2-3kg. of R23, oil for R23, an oil separator and god knows what more ^^

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One system is bad enough. Two systems (cascade) can really make you crazy. So what we need to do is forget that we have a low stage. Leave it off and forget that it exists.

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I actually like it, its fun and its a great feeling when your temps fall down from the initial non calibrated system from -10C to lets say -35C ^^ And i think that calibrating my cascade will be very simple beacause i use electromagnetic car injectors wich i can digitally control so i have to only fill the system up so freon gets to them + some extra and all i have to do is get the proper steering frequency....

Condenser airflow is good. Relative condenser sizing is good. Your low side guage may be out of calibration. Does it read zero psi when open to atmosphere?

What makes you think the system is overcharged? I disagree. It is charged just right.

On changing the TXV orifice, we can't tell if it is right or not at this point. There is no need to change it until we see how it performs under load.

Haha then im very lucky ;] Or ive got a 6th sense ;]

Ive finetuned it a little, i get -40C on the exchnager and the temp goes down there very quick so it has a nice pull down... and during pull down the condenser gets really hot (it has 3 loops) and 2 of them (the outer tubes) have like 40C and the inner cools it a little more

So far so good. :D

What have you fine tuned? When you change something, you should take new temperature and pressure measurements so we can see what effect it has all over the system. Everything is connected to everything, and a change somewhere is a change everywhere.

Let some freon out ;] Just a little and pressures on the low side dropped but it goes down with the temps insanely fast comparing to what was earlyer, like 3-4x faster to -40C

The txv has a 00X orifice and its opened to the max, intill the screwdriver bends ;] Its rated for 200 or 250W @ -40C, how do you thing, is the flow through it sufficient ?

Some pics of the isolation im working on (didnt test it yet with this isolation cause its not finished)

Pipes

We need the complete list of temperatures and pressures to see what the system is doing. Don't worry about the orifice size for now. We are not going for lowest temp at this point. We want the charge right and the TXV setting right.

If you adjust the high stage system for lowest temp with no load, then when you start the low stage system, giving it a full load, it will not perform well.

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If you adjust the high stage system for lowest temp with no load, then when you start the low stage system, giving it a full load, it will not perform well.

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eeee ? :D

Didnt quite understand :D high stage = II stage, low stage = I stage ? :o

High stage = high temp stage = stage 1
Low stage = low temp stage = stage 2

could you drop in over here ?

http://polchat.pl/chat/?room=brqt

its a chat

Exchanger drying

Txv's bulb and the termometers probe

Finished the I stage

I would like to thank you guys for all your support, especially Gary for his help with calibrating the whole thing and Bowman for all the ideas and help

2nd pic of the I stage

Isolation

Isolation 2

Isolation 3

The TXV isolated (with a special spunge, neoprene and polyethylene foam)

Fans cooling the I stages condenser

The start capacitor

I gotta mount the fans on the compressor again and make a stand for the filter / txv assembly cause it hangs in air and is a little indangered\ vibrates

The fans wich will be cooling my I stage compressor (there are 2 more for my II stage compressor)

NICE!! thats come good condensation proofin! what cfm are those fans? they look like 120's so im guessin like 108cfm...?

110 cfm ;]

Oh, forgot to post one more pic ;]

damn beruk isnt it like 3 in the morning where you are?

you have to add 6 hours :)

Totally insane! :slobber: , but you gotta love it.

So after 15 pages I'm sorta getting the idea, but what is the heat exchanger cooling on the low temp circuit? the capillary or the condenser line or does it replace the condenser?

I feel like a MF retard after reading through this. Same age and i cant even comprehend what you are doing lol.

Good work mate, keep it up.

Cascading two refrigeration systems is just like stacking pelts. A refrigeration system has a hot side (condenser) and a cold side (evaporator). The interstage heat exchanger is the condenser for the low stage and the evaporator for the high stage.

So the idea would be to use an extreme refrigerant in the low stage and a large capacity compressor with good refrigerant in the high stage.
Is R13 still available as that would make a excellent low stage refrigerant -81c boiling point :slobber: and the cascade would control the pressure.

Back from hell :o I was on 10 day holidays on beach... Thank god water in baltic sea was really hot, 21C (normally hovers around 9-13C)

Well, came back to see my cascade completely out of freon and i cant find that darn leak, ill do some more pressure tests on the condenser...

But there are some good news :| I found a much better injector, the old ones were from a golf II (fully electronic injection and engine manegment) but their nozzles were really small so i was afraid if the flow would be high enough :\ But after some talk with my dad he told me about a startup injector from our new car (an old ford escort rs)... Finnaly i could see it today and its MUCH better, it has a ~ 0.026-0.04 id nozzle (cant tell it w/o any real comparsion) so its a real overkill

Why i want a overkill ? I dont fear that the injector is too small, if i open it up to the max i have a very fast pull down and than triggering it on/ off i can dosage right amounts of freon and thanks to coppers lage heat capacity the temp wont fluctuate when dosaging it.

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you have to add 6 hours

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Jak milo widziec polaka na XS ;] Jeszcze chyba tylko Quad tutaj jest z Polski :D

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Totally insane! , but you gotta love it.

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I hate it cause it leaks all the time ;|

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So after 15 pages I'm sorta getting the idea, but what is the heat exchanger cooling on the low temp circuit? the capillary or the condenser line or does it replace the condenser?

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The I stage's evap cools the II stages condenser, thats the secret ;]

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I feel like a MF retard after reading through this. Same age and i cant even comprehend what you are doing lol.

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Thats one of the pros of being a Pole ;] Scholl sucks here cause they teach you everything + ive always been addicted to technique, encyclopedias etc. + ive got a great dad that teached me everything i had to know to do this stuff

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Good work mate, keep it up.

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Ohh i will keep it up untill my barton screams for help :D

Ok and the first pic: old vs new injector

Forgot to mention the old one is on the top and the new one is below ;]

And some more

You can see the electrical connection above

And one more:

A knother angle

As you can see the injector uses a banjo connector...

And one last pic: the nozzle:

nice man! u kinda slowed down on it? or final touches being takin care of...?

Ive been on holidays + theres a god damned st. marias greens holiday (longer weekend) and no shops etc. are opened.... Damn i hate it

Ok, im letting the freon out of the I stage (its poluted with air cause the cascade wasnt vacuumed right), than ill start searching for that god damned leak (hope ill find it finally) and when i mount everything back ill do it better: ill add a subchiller on the suction line (ill just solder a 6mm copper pipe to it)

sweet! lol this thing is going to be badass when its done...what kinda temps are we going to be talking here?

-25 to -35C loaded

found leak?

looking for it

Ok few pics presenting looking for those god damn leaks...

Pic from yesterday: letting freon out (was contaminated with air cause i didnt vacuum properly)

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Jak milo widziec polaka na XS ;] Jeszcze chyba tylko Quad tutaj jest z Polski :D

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i am only reading what you guys are doing with your pc's :P

:toast:

i've seen spiderman's posts...

:rolleyes:

berkut how long have you been doing this now ? year ? year and 1/2 ?

btw, i'm in usa (manassas, va) now :D

Ok, new stuff

First of all i found that god damn mother §§§§ing leak, its in the condenser, found it this way:

Heres a pic of the isolation i used, the first layer was a foam wich is used to pack computer stuff and the second is normal isolation foam, in the finished unit ill use 2cm armaflex

And the pic od the subchiller being made (the thing wich lacked in the first revision)

Ill give some more percise pics later

damn -25/-35 load is damn good! lol what kinda setup u puttin this on?

This is the I stage so it will cool the II stage and the cpu ;]

And it will sit on a barton 2500+ and later on a sk8n + opteron 140

Ok, 2 pics of my subchiller rdy

Gotta clean it from soldering paste :\

And the 2 pic

How much do you think this thing will cost you in the end? Looks like a lot of various items are needed

Gonna be worth it though :slobber:

berkut, are you using an oil separator in this setup?

I cant wait to see this thing run. Ive been watching this thread since its beginning. Hurry up Berkut! LOL keep up the good work

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Originally posted by pc ice
i too have been following this thread with great anticipation.
the end result's should be worth the time and money.
but i dont want him to hurry and finish becuase i enjoy reading all his finding's and great work....hope it never end's..

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/me also

BUT, as he gets closer the psi goes up. As does the danger. The cascade can be positively lethal.

As far as money goes, if he posts a paypal donate ill donate a few bucks hes making progress.

]JR[

sorry for the slowdown guys, that darn I stage still leaks and i cant find the leak :\

i dont do anythin with it right now, i have to buy more parts and a condenser probably (but during the tests it didnt leak)


Im also made a lil micro chiller, its a small phase change made out of my II stages cascades compressor and an old condenser + a 120mm fan

as an evap i use a frimped from one side and brazed from the other 28mm OD tube to a 5x5x3mm plate

its made to make me more happy, at least this system doesent leek and i can test some mounting ideas

pic of the isolation hardening on my evap

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BUT, as he gets closer the psi goes up. As does the danger. The cascade can be positively lethal.]JR[

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Thats why i was in a shop today, www.berling.com.pl (currently the best shop in poland as far as it goes for me, love these guys, they help a lot, extremelly customer friendly) for some parts.

Bought a high side presostat, a electromagnetic valve, filters for the first and second stage, 6 service valves and some pipe caps.

Where i will use the electromagnetic valve and presostat ? Here we go:

The presostat will be connected to the compressors outlet before the condenser (so as little as possible gas goes there) where it will be set to lets say 15 bar. During normal working conditions the I stage should keep the II stages condenser nice and cool so the pressures are low, lets say 10 bar. But if the I stage failures- cooling dissapears, pressure in the II stage raises, the gas in the condenser has almost no where to go and would go kaboom if there wasnt the electromagnetic valve between the high and low pressure sides. The presostat openes the valve and the compressor in the II and I stages shut down (electricity is cut down), pressures go down cause the freon can go to the relief tank and nothing bad happens.

Normally when the system is shut off the valve is also opened to let the freon flow from the condenser to the relief tank on the low temp side.

This way i get rid of few problems i had.

Some pics; the presostat:

The electromagnetic valve

Some other stuff i bought (for the chipset evap and maybe vga evap)

The future evaps

One more pic

And the compressor i got for free today (the guy wich gave it to me saw my work)

The model number

Think its a 10000btu/h, its a Tecumesh produced under some italian company brand

And the compressor cleaned

Nice compressor man.

Looks to be like a 1HP LBP model?

Always a kick to go shopping for parts!

What gonna happen to the new compressor?

Dunno yet, probably ill use it to cool my chipset and graphics card

damn u lucky boy! how much is that worth? in US ? nice work man!!!

Ok... ran in to troubles with that damn cascade, it never stopped leaking...

As i counted it- there were 3 revisions of the cascade's prototypes (all not working) and this would be the 4th, so ill call it MK4...

I wont post any info on it as long as i wont be sure that at least the I stage works... That will be in like 2-3 days, but ill take pics etc so there will be a nice gallery...

One pic of the frame i made of wood and aliminium, you can see the 10k btu tecumesh and the old sanyo compressor... and the almost empty can of R22 wich will be used as a relief tank..

Tak jak napisalem w PM - swietna robota stary!

Sorry for non english insert:)

I wish I was still in High Sk001 and had so much time to modding... :(

Nevertheless, I had an ide for a long time doing rounds inside my skull.

What about using some powerfull phase change contraption to k001 226watt pelt?

Non load temp delta is 60C, so if you managed to keep hot side @ let's say -20C under load (~300watts of heat load for the hot side) you'd get -80 load temps on the other side, right?

Or maybe it'd be better to water cool sauch a pelt with chilled coolant liquid cooling setup (Swiftech MCW5000P-T)
Would it be possible to get coolant to -20 under load?

I heard that peltiers lose efficency after a certain temperature.

I'm pretty sure tha a peltier at -30 would act as an insulator.

I guess Berkut could try this idea out pretty quickly (I hope)

The pelt adds a great deal of heat in addition to its disadvantages at low temps. If you are going to stack a pelt and a phase change system, it would make more sense to put the pelt on top.

For example, if we added an air cooled pelt in series with (after) the condenser on a prommie, dropping the condensing temperature 25C or thereabouts, we could switch it to R404A without changing the cap tube, and achieve substantially lower temps than any of the R404A prommie mods thus far.

With this mod, I might even be tempted to go with R410A for even lower temps, although this would require dropping the condensing temp by about 30C or so to avoid changing the cap tube.

Either way, we would want to run the pelt until it gets very cold before starting the phase change system.

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Tak jak napisalem w PM - swietna robota stary!

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Thx, ale dopuki nie skoncze dziela to wciaz bedzie tylko sterta miedzi i innego zelastwa ;]

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I wish I was still in High Sk001 and had so much time to modding...

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I have final exams this year (maturka...)

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What about using some powerfull phase change contraption to k001 226watt pelt?

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@ ~-40C peltiers are 50% efficient- @ -40C a 200W pelt is only 100W...

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Non load temp delta is 60C, so if you managed to keep hot side @ let's say -20C under load (~300watts of heat load for the hot side) you'd get -80 load temps on the other side, right?

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nope... im not a pelt guru but i can say that fully loaded, cpu + pelt can put out over 400W of heat easyly

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Or maybe it'd be better to water cool sauch a pelt with chilled coolant liquid cooling setup (Swiftech MCW5000P-T)
Would it be possible to get coolant to -20 under load?

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Its not efficient.. the best way to cool water is the vapour phase change way..

Gary- i dont think a pelt would do the job if it comes to subcooling freon... Its to weak i think, it would be better to use a small refrigerator compressor as a dedicated subchiller...

I'm not talking about subcooling. The condenser would cool the refrigerant coming from the compressor to room temperature, and the pelt would condense it below room temperature. To be sure, it would take a big pelt or maybe two pelts. Something like 300-400W. If big enough, the condenser would not be needed. It would act the same as a cascade interstage heat exchanger, with the pelt(s) being the high stage.

Hi, which gases do you use on the two stages ?

Welcome to Xtreme zytrahus:D
:toast:

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Originally posted by TheDude
Welcome to Xtreme zytrahus:D
:toast:

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thx ;)


I found your thread and Xtrem-Systems, I'm just building two systems, one two stages and an other three stages.


What gases do yo use ?

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Originally posted by zytrahus
What gases do yo use ?

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Thats the $1m question ;)

]JR[

no less than $3 lol

There're many combinaisons...

There are a great many possible combinations. The traditional mix would be: R22 or R502 in the high stage. R13, ethane or ethylene in the low stage. If a third stage is added, this would contain R14.

Each of these refrigerants have suitable substitutes with similar characteristics.

My 3 cascade cooling system is : propane / ethane / R14

soon ready

Although us hobbyists have problems obtaining high pressure refrigerants that we can use, noble gases, co2, oxygen, nitrogen are easy to get but difficult to use.

]JR[

Do NOT ever even consider using oxygen. Put that thought entirely out of your mind.

Oxygen + Oil = Bomb

Spontaneous combustion. No spark needed. People with oxy/acetylene torches have been killed by cleaning the oxygen regulator with soap, because the soap contains oil.

+1

lol, i was just listing what i can get...

All the noble gases have condensing pressures way out of scope for a 2 stage cascade, going for a 3 stage is no easier because i'd still be missing the intermediate like ethane :/

Surely there is something we have overlooked in terms of a ghetto high pressure refrigerant?

]JR[

ethane roxxx