dual evap rotary SS

[tim-]

New unit for a swedish overclocker :) a dual evap unit for 2x8800ultra with the possibility to run it on cpu+gpu if you want to run single card... well work in progress.. going to be tuned for 250watt on each head.

http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0165.JPG
Still missing evaps.. duniek where are they? ;)

http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0166.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0167.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0168.JPG

no case as customer requested.

[tim-]

some paint is always nice.. notice I have switch the suction from right to left side of unit as well as rotate the compressor 90dgr counter-clockwise. This is made to make it fit better on customers bench table as he is running cascade on left side of mobo, and this on right side.

http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0169.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0170.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0171.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0172.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0173.JPG

just high pressure side and evap left to braze :)

an additional electrical box will be added with powerswitch connected... ofcourse cover hood will be screwed on.

regards
Tim

[runmc]

I would love to see how this works :up: Good luck :D

[Lord_RTKK]

It looks very nice... :D

Please, PM me with the price and we can talk about some things that I want... ;)

Regards,
Lord.

[gosmeyer]

Simple and to the point. I hope it rocks.:yepp:

[Nosfer@tu]

tim, it is great you live sooo close :D

Only 600 km :p

[Duh]

ohhh man!! id kill for that unit... cant imagine my xp 2400 having sub 10 s in spi 1 M :D

[tim-]

a little update.. a little late too. Have been much to do at university now in the beginning.. going out like all nights this week but today i decided to take off and make som progress with my units, sleep (6h last two nights) and some exercise...

http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0186.JPG
high pressure line is brazed on condenser, just checking if it fits before brazing on compressor.
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0187.JPG
view from above. As you can see outlet is not brazed yet.
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0188.JPG
here is filter/drier with a little U-bend on outlet. This is to make it easier to braze of and on captube for adjustment as I guess I will have to play alot with it as it's new to me with two evaporators with captube. i have done it before but it have been with valves.
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0189.JPG
another view.
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0191.JPG
outlet is now brazed on.
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0190.JPG
it fits pretty good I think.

high pressure side is done! Now I'm only waiting for evaps to arrive... thinking of starting with something like 2,6m of 0,7captube.. any suggestion on that?

regards
Tim

[tim-]

http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0192.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0193.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0194.JPG

some insulation is done. wanted to se how it looks and it looks good I think. the last things with insulation will be done when evap is brazed and captube adjusted proper. I start with 260cm 0,7mm captube to start with.. think I will end in ~220-230cm range.

No slhx to start with as I think it will reduce performance instead of increase it cause of the big load (2x250watt).

we will se as soon as I get some evaps.

regards
Tim

[Nosfer@tu]

Love your work m8.

Cant wait to have those mach 2 Modded :D

[tim-]

thank's man I hope you will like them :)

some other pictures.
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0196.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0197.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0198.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0199.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0200.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0001.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0002.JPG

sleeving and most of the insulation is done. Just have to braze evap and adjust captube then it's fit for fight. starting with 2.6mm 0,7mm captube.

[Freddie123]

Are you using 1 cptube to feed both heads? How does that work?

[tim-]

cptube? capillary tube? no I have one to each head 260cm/102inch of 0,7mm/0,028" ID.

will charge unit with r404 or r410. I think r410 would suit this unit better then most SS 'cause of the HUGE load.

[n00b 0f l337]

Be prepared for some huge discharge pressures then.

[Freddie123]

Yeah a R410 blend might be better... Especially as its a commercial unit, high discharge pressures arn't worth risking

[krullet]

cant w8 to get this home to me, and test it..
im really hoping that the evapps comes this week

[tim-]

Krullet:
I really hope so too, we have to cross our fingers and hope Duniek will have them finished mon/thuesday as he said. otherwise I have to order some other evaps for your unit aswell as my own.

Freddie123:
yes, a blend have crossed my mind too. I don't like such blends as it hard to measure superheat and subcooling.

20-21bar(a) discharge isn't the problem, it's the delta between hi and lo side which can be a bit big for a safe and long life run.. we will se how this will go I will atleast try some mix. Also I have to check the maximal delta allowed on compressor. Normally it's like 15:1 on piston compressors but if I'm not wrong it's okay to run bit bigger delta on rotaries.. have to chech data sheet.

did some modifications with the electrical stuff. used some "submarines" instead of the original screw connections.

this is how the submarines looks like:
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0008.JPG

and this is the result:
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0004.JPG
the hood isn't tighten enough so it isn't 100% fixed and therefore it's a little "sloping".. it's fixed now.
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0007.JPG
a picture of unit.. sleevings is on too. next update will proberbly ne when evaps arrive.

regards
Tim

[Oliver]

The unit is so clean IMO and looks really good.

Keep up the good work ;).

[Clemmaster]

We call it compression ratio. The lower it is, the better are the performance.

2.60m of 0.7mm is WAY too long for that, and R410a is total suicide ;)

[tim-]

if you say so it's proberbly true. I havn't been playing that much with captube. Especially not in dual evap units. I want to give captube a chance before I replace it with cpevs.

what do you think will be a proper lenght? I have tried DanCap (danfoss program to calculate captube lenght) and it says 41centimeter with parameters that's wrong and I can't adjust so that's not usefull. In my hvac literature it isn't much wrote about captube as it isn't very common. I don't know how to calculate proper lenght to be honest...

I'm aiming for -45@ both heads which I hope is possible reach as I have reached -60@250watt load with same model of compressor with r404a. it was reached with cpev.

regards
Tim

[Clemmaster]

I've never played with 0.7mm captube so I can't tell you any length as it's not the same length at all between captubes, for example I've a "table" that makes approximately a convertion between 0.6 0.8 and 1mm captube but it's given for 2*0.6mm, not 1, don't know why :D.

The pressure drop depends on the compressor and the gas too. I'd put 2*2m20 of 0.8mm with a good LBP compressor, but I don't know what is the corresponding length for 0.7 one. I would start with 2m of 0.7, the pressure drop may be enough but that's hard to tell, especially on dual vaps :/

I'm building a dual vap based on NL11F for a couple C2Q/8800GTX, I've started with 2*1m90 of 0.8mm as the compressor won't be able to run under -30° once loaded.

[tim-]

okay, then I have something to go on. I can do the math between 0,8 and 0,7mm captube.

I have shorten captubes and will start on 2.3meter of 0.7mm. I prefer to shorten it over make longer.

btw voltmodded 8800cards produce more heat then quad think about that.

[Clemmaster]

You won't have to make it longer ;)
2m40 of 0.8 is more than enough to carry good load on single vap, making the conversion you'd be near from 2m of 0.7 I think, so with 2 evap and a bigger load shorten it will be necessary.

And forget about R410a :p

[Nosfer@tu]

HEHE I love it when you go into such specific thermodynamics and I just dont follow you :D
It is like the first time you read about ss cooling :D
WOW :D

[Freddie123]

If I was building that system on a single evap i'd use around 210-220cm of 0.8 however, i'm not sure how much difference a dual evap makes to captube sizing. I think you use the same amount. Sorry to disagree Clem but i'd use 240cm on around 225w load for 250 i'd shorten it

[Clemmaster]

If I was building that system on a single evap i'd use around 210-220cm of 0.8 however, i'm not sure how much difference a dual evap makes to captube sizing. I think you use the same amount. Sorry to disagree Clem but i'd use 240cm on around 225w load for 250 i'd shorten it

Depending on the compressor displacement and the temperature you aim at getting. Of course I'd use less than 240cm with an 1/4hp or MBP compressor but with bigger ones (34cc LBP, such as GS34CLX or CAJ2464Z) I'd go up to 2m60. You must find the best relation between captube size and refrigerant quantity anyway. It depends on the compressor you're using, the temperature you're aiming at getting and the refrigerant you're using (I'd shorten of 20cm with R22 compared to R507c/R404a, for an other reason)

[tim-]

we will see. I will have both r410 and r404 available when unit is ready for tuning so we will se. I have also ordered r410 scales for my refco m4 deluxe snapon manifold so I will have the possibility to measure superheat and such pretty easy without having PT-charts printed on paper.

I havn't had time to do the math yet as I'm currently study for a math exanimation on thursday. pretty busy at the moment.

as I said, have no experience of captube in dual evap units so I know as little as you of the practical.. theory isn't always the true ;)

[tim-]

long time since update
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0075.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0076.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0077.JPG

evaps arrived today and I did some milling job on those.. very nice quality.. It's LDs evaps. the gpu evap is made out of a cpu.. so it's as you can se modified.

http://phasechange.se/photos/units/peterandtommach2mod/tb_DSCN0068.JPG
http://phasechange.se/photos/units/peterandtommach2mod/tb_DSCN0069.JPG
http://phasechange.se/photos/units/peterandtommach2mod/tb_DSCN0070.JPG
http://phasechange.se/photos/units/peterandtommach2mod/tb_DSCN0071.JPG
http://phasechange.se/photos/units/peterandtommach2mod/tb_DSCN0072.JPG
http://phasechange.se/photos/units/peterandtommach2mod/tb_DSCN0074.JPG

some other photos of evaps. a small batch of 5 was bought this time.

this weekend I'm aiming to have 4 units up n running included this dual evap one.

updated with more pictures and temptures later...

//tim

[TopherTony]

looking nice, hope it turns out like you hope.

Leak tested?

[tim-]

yes pressuretested.
one small leak in connection evap-flexhose. VERY small didn't hear it with 20bar in system. I had hard time to find it even with soap. very small as i said. it's fixed (just heated the pipe a little and it was fine).

now unit is vacuuming... ~1H left and it should be fine (a bit lower then 400microns right now).


http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0094.JPG

my tables is pretty messy, to much on it. But as I'm brazing another unit on the clean table I hooked it up for vacuuming here.

[noobzed]

very nice unit mate!

[tim-]

http://phasechange.se/photos/units/krulletsdualevapSS/tb_DSCN0100.JPG

it's alive!
idle temps with decent temptures as start when I'm going to loadtest it for first time tomorrow (clock is 1:40 in the morning, time for bed).

maybe it need a little captube adjustment to get a smaller delta K between evaps. currently 2-2,5K delta. as one is drilled in side we will se how it went under load.. maybe not necessary to adjust it. idle temps is nothing to care about. Strange thing is the sli evap have lower tempture then cpu evap with same captube lenght.

we will see, waiting for r410 aswell. will mix it when it arrives (hopefully middle of this week).

regards
tim

[runmc]

I always pressure test before I insulate ;) Nice unit

[tim-]

runmc:
I pressuretesteded it before insulation to..

the insulation on suctionline (expect on flex) is not glued or taped.

all joints was visible under pressuretest and evaps was in water bath.

it's leakfree for sure :) will do some load tests later.. currently milling the second loadtester.

[tim-]

sorry for double posting but I just wanted to share the results
I took the advantage from stand alone to case kitted unit as I had a case spare :)

http://phasechange.se/photos/units/krulletsdualevapSS/v2/tb_DSCN0189.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/v2/tb_DSCN0196.JPG
http://phasechange.se/photos/units/krulletsdualevapSS/v2/tb_DSCN0205.jpg

both evaps is loaded with 225-230w load (pending 'cause of socket voltage).
there have been alot of playing with captube and refrigrant blend to get those temptures. I have triend different lenghts and size of captube and finally it ended up like this. I don't care to much about the difference on almost 2K between evaps since it is so many things that can 'cause it, first of all different evap designs as one of them have outlet in side and expect that it can be wrong in measurement. 2K is still good delta between evaps. strange thing is that the gpu specific evap holds better temp then the non-modded cpu evap. Both evaps is from beginning LDs spiral evap, VERY good evap for SS.

I think I beat piotres dual evap in performance with this unit :)

[TopherTony]

Congrats :up:
looks real nice

[gosmeyer]

Well done and to the point.
What was the final sizes on cap tubes and what mixture did you settle on?

[tim-]

final size something between 275-290cm of 0.8mm captube on each head (same lenght +-50mm) with r410/r404 mix. I don't have exact blending mix but it was ~70% r404 and ~30&r410.

i did try pure r410 but it didn't give better temp, same for r404.. blending was the best option i had. R402 may give some advantage but it's illegal in sweden.

[PhilippF]

What HP and LP did you have idle and under load? And at which room temp?

EDIT: Very nice unit btw... :)

[tim-]

loaded I had 14.5bar(a) highside and 0,85-0.9bar(a) on lowside. airtemp~20,0-20,3*c, outlet condenser slightly over 25*c during load, VERY good capacity in condensers.

idle temps drops a couple of degrees out of condenser and pressure drops to 13.5bar(a) highside and ~0,75 bar(a) on suction. it sounds like low pressures but in fact as I can ceep 25*c during load with regular roomtemp that's not a problem the lower pressure add more capacity to unit to.

[Marvin]

tim, is it a Refco rl2 or RL4 ?
congratulations

[kayl]

nice work tim :up:
dual head units are alot of fun arnt they :D

[tim-]

marvin:
sadly it's just a rl2, takes very long time to vacuuming those units compare to my old refco ~9cfm, but this one can make the beutyfull numbers below 100microns.

Kayl:
yes it is :D I will proberbly take the step for tripple head soon too :D

I would really like to se a dual head competition here on XS soon :D maybe dual head cascade competition? :) I'm in!

[jinu117]

How did I miss this? Very nice unit you made there tim :)
Honestly for small system, I really didn't see diff between 2cfm and 6 cfm pump on actual vacuum level past 1000 micron? (talking about closed system pressure not something you read off while running vacuum).
I don't think I have time to try for competition things setup, maybe someone else can? :)
As for the evap, I was expecting to see some modification other than making brazing easier part... it's basically chilly1 evap which has been old but trusted design. I just wanted to correct and give credit where it is due :P

[tim-]

I don't know what the difference is between those evaps and chillys original. only thing I know for sure is that those is as easy as it can be to braze and performs very well under this kind of load when I replaced 0,7mm captube to 0,8mm.

i'm looking forward to get some more time to play with multi evap units as in such units. A competition like this will proberby be very good as there is more and more people who are requesting multi head units for gfxes and cpus.

regards
Tim

[LittleDevil]

Really nice unit my friend and nice temps. :up:

Kind Regards

[ryba]

both evaps is loaded with 225-230w load (pending 'cause of socket voltage).



This load is sum of each evap or on each evap you have 225-230W load?

[tim-]

my mistake 225-230w EACH head, 455 totally.

[ryba]

my mistake 225-230w EACH head, 455 totally.


Ok, I must concede, you have very nice and powerfull sli :) I'm building my own, thx for info.