People get carried away with the sight glass thing. It is borderline useful on a TXV system, and utterly useless on a cap tube system. Whatsmore some systems should have solid liquid and some should not.
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People get carried away with the sight glass thing. It is borderline useful on a TXV system, and utterly useless on a cap tube system. Whatsmore some systems should have solid liquid and some should not.
And under some conditions a cap tube will have solid liquid and at others no liquid at all.
Compressor is 1/4HP LBP, unfortunetely i cant find any smaller cap tube.
Gary would it be better for solid liquid in the cap entrance ? why spray useless vapour in the evaporator?The vapour wont cool anything and it will raise (a little) the suction pressure.
i doupt if the vapour entering the cap tube can be liquified in its way inside the cap tube even if it runs inside the suction line.
I got a hundred feet of cap tube 0.026 where u at... pm me....
HAs anyone seen GARY ????
nadda
I'm not 100% sure, but I though I saw a post from him @ the other place more recent than here....
I remember awhile ago he said that he had some real life issues he needed to concentrate on.
I wonder whats up with Gary too!Quote:
Originally Posted by chilly1
Have you asked runmc whats up with him? Maybe he knows!
Personal things took Gary away from us.. quite long time was passed since he disappeared
I read a lot of gary's posts, hope he is alright.
I dont quite understand this. I would think that it would have no more impact on the efficiency than any other piece of pipe in the system. Also, starting my first build, I would like to use it just to make sure the system is dry and for the visual indicator that the refrigerant is condencing. How much efficiency am I loosing if I use it?Quote:
you don't want to use a sight glass on a captube system it acts as a small reciever and will reduce effeciency.
Practically none if you dont oversize it.
Actually the refrigerant condenses mostly in the capillary tube so aliquid full sightglass and the system will be overcharges. In a capillary tube system we use a simple liquid line temperature test to determine proper charge.Quote:
Originally Posted by labrat23
I have a question for chilly1 or someone else who uses low temp refrigerants: How much capillary tubing would you use for refrigerants like ethlylene? Co2? R-14? Or would you have to use a TXV?
Thanks chilly. I dont have a large supply of refrigerant, so I'll be keeping the overcharging/unnecessary charging to a minimum.
Depends upon your configuration. For ethlyene I use 60 inches of 0.040 when I am using a TXV first stage and want 250 watt load at -85C stableQuote:
Originally Posted by MutantToad
If I want colder I lengthen it. For -100C I use 75 inches of 0.040
R14 I use the same, I DOnt use Co2 in cascades.
Keep in mind these sizes also need to have teh captube subcooled properly for stability and static charges will be in the 180 to 200 PSI range. This will give you enough Refrigerant mass inteh system to provide proper flow so the compressors will not over heat.
Chilly do these systems operate different than a normal system?if so is it because of the small evap? refrigerant is condensed in the condensor and goes into the liquid line to the cap tube. Cap tubes are susposed to have a liquid seal to operate properly.Any thing I have ever worked on never condensed refrigerant in the cap tube.
Well most systems including hose hold refrigerators will throttle a mix of gas and refrigerant in teh capillary tube this is a kind of self metering system when properly charged.
EXP. A system charged to a solid liquid stream the capillary tube is not attached to the suction system. Flow is dependant upon room and cabinet temperature only.
EXP2 A system has a capillary tube attached to the suction line and is charged with both gas and liquid entering the capillary tube. The capillary is cooled by the suction so the gas condenses to a liquid and this is dependant upon how cold the cabinet is. As the suction line gets colder there is a longer liquid stream in the capillary. This increases the static pressure in the capillary lowering the flow causing the suction line to warm slightly. In this way the system achieves static balance.
every system i work on condenses the refrigerant to liquid in the condensor, it is sub-cooled by a few degrees before it leaves the condensor, it is completly liquid in the liquid line.then it goes to the cap tube. my understanding is it travels about 2/3 down the cap tube before it start to vaporrize from the low pressure acting on it. the cap tube meters the refrigerant,it does not condense there in a normaly system.
Hey, I was wondering how long of a cap tube I would require with ~280W to ~310W heat load? The gas is R404a. The reason I ask is if I try to calculate my length with the "forumula" you gave then I either wind up in the negative or something quite close. Thanks a lot, - Peter.
Can people please post some experience with 0.031 captube here.
The rule in the 1st post by gary says multiply by 1.6 but you then end up with something crazy like 5+ metres for almost any load.
Personally I find best results around 2.8 - 3 metres sofar
I am planning to use 4 m of 0.031 for 200w of heat load.
Im not sure but I think thats way too long especially for a 200watt heatload. I had 3.5 on my gpu unit charged for 100 watts and it was too long, since I made it 2.8 metres results are great.
If it was me Id use 2.5metres for that heatload, I know it doesnt make sense and is half the length of what this thread suggests I think it will work better.
This was all using 404a, and I still struggled to get good results.
Can Chilly1 please comment on this post...
you guys can't calculate very well I think :D
200 watt r404a/r507 gary's rule states:
3 meter for 150 watt of 0.028. 200-150=50. 50/15= 3 1/3. 3 1/3*30=100cm shorter. So that's 2 meter of 0.028 for 200watt. 2*1.6=3.2 meter of 0.031" for 200watt!
Well build a system put 200 W with that length of cap tubing for 0.031.... see if it can even hold load..... The 1.6 is widely acknowledged rules yes... but that is moving from one idealistic to another idealistic condition. I've seen different result in real life testing.Quote:
Originally Posted by Unknown_road
I'm using 3.2m of 0.031 with good results with r502, but I think 0.028 are more widely used, 200cm of 0.028 is ok for 200watts loads
first off all I was just explaining gary's rule. Second of all my experience is that 3 meter of 0.031 can hold 200wattQuote:
Originally Posted by jinu117
eternal question comes up again... which no one has answered from my experience... WHAT is 200W in CPU load? :P Voltage, cpu and overclock will do nicely lol... Where does your experience with 200Watt comes from?Quote:
Originally Posted by Unknown_road
I am not trying to be an ass here but I think we have way too many wide varying idea of what 200W is when the simple thing is... 200W is 200W... -_-;
load test block.............Quote:
Originally Posted by jinu117
how long captube should i use for 50 watt load?
i am use it on my G4 eMac, stack wattage is 22 watts.
i will be using R134a, or maybe r404a with a 1/6hp compressor.
according to rule i should use about 25' of 0.031
i was think to start with 24' of 0.031 and shorting if needed.
Just stick to conventional cap tube. You will still have nice freezy -40c or below.Quote:
Originally Posted by the_new_guy
so is 14' of 0.031 good?
go with 0.026"
why do u say so?
i heard 0.031 is better as it has less chances of blockage
My strongest units with 1/4 hp NF9FX is 9ft 2inches to 9ft 6inches of .031. We are talking loaded evap temp with dual core 1.7v @ -42c below. Anything shorter will be hard to tune for good temp with current crop of cpu without liquid slugging... anything longer... you will see better temp with lower load but not great temp on high voltage power hungry cpus.
I have 0.7mm captube and R402a gas... How long is best for 180 - 200W load?
tnx
Guestimate 2/2.20mts, at least that's what I'll try next time.
I just tried it using this rule & it wasent pretty :p: using a 1h rotary w/R290 & evap temps dropped off the face of the earth..Quote:
Originally Posted by jinu117
EXACTLY 3.2M of .031" Cap my evap temps drop to -25c & that's with just a mild overclock on my Fx. I'd guess around 160w load. Couldnt hold the load regardless of the charge.
Idle temps where pretty good at around -45c. My small Vapochill SE could hold a better load.
Im guessing 2.6M .031" should be just about right?
C-BuZz
I have been experimenting with 0.031 on a few systems.
As Jinnu above I find that longer than 3 meters becomes too restrictive mostly especially when you charge for a high heatload. You struggle to hold load temp.
Like Jinu117 for me 2.7m - 2.8m have worked well in general from smaller (1/5hp) systems too a 3/4hp monster its a good length too start with
If ya make a good heatload tester there is not way in the world a 200W load tested = 200w CPUQuote:
Originally Posted by jinu117
even 150w to 180W with a load tester is massive.
some of the mistakes ppl do when making resistor load is that the resistors used are no where near flat, and dont make very good contact with the metal plates. Also the clamping pressure between the resistors/ cold plate and CPu block need to be good, other wise ya cant remove the heat.
:toast: perfectly said jinu117.i use around ~3m for singles and around 2.5m for cascades.Quote:
Originally Posted by jinu117
if you insulate that suction line real real good ya can use that tad bit longer capillary line.
ppl are forgetting some of the most important things when build a system. A system running at its coldest is not a system thats gonna last for eva.
Too short a capillary line, and yes you will handle nice load for benches.
But when a room starts to heatup and you start benching for a few hours with heavy programs you just cant keep the liquid refrigerant from swamping the compressor and before ya know it ya got 2k supaheat, then comes 0k and the evap temps slowly warm up.:mad:
I wonder how many ppl actually have 10-15K supaheat at heavy load??
Too long a capillary line and you can get nicer idle temps, but once the compressor gets up to temp, you really risk overheating that compressor.
I think I have been noticing this, on my system running R22 I notice that after about 5 min of pulling down to temp its at its coldest (Idle around -26c cpu die temp read in windows, load around -5c cpu die temp) and after about 3hrs or so its idling at about -22c and about 0c load. This this is due to cap tube sizing or is my condenser not removing enough heat to be condesing at its best due to High discharge temps of R22?Quote:
Originally Posted by kayl
[QUOTE=Fhqwhgads6680][QUOTE=kayl]
But when a room starts to heatup and you start benching for a few hours with heavy programs you just cant keep the liquid refrigerant from swamping the compressor and before ya know it ya got 2k supaheat, then comes 0k and the evap temps slowly warm up.:mad:
its hard to say exactly.Quote:
I think I have been noticing this, on my system running R22 I notice that after about 5 min of pulling down to temp its at its coldest (Idle around -26c cpu die temp read in windows, load around -5c cpu die temp) and after about 3hrs or so its idling at about -22c and about 0c load. This this is due to cap tube sizing or is my condenser not removing enough heat to be condesing at its best due to High discharge temps of R22?
from what i hacve noticed, when the compressor is cold and suction warm on firt turn on, this is when you will get your best temps.
As the compressor heats up and the suction line slowly getc cold all the way back to the compressor ya losse a few c's.
I personlly found r22 very hard to use hey, those 240+PSIG high side pressures make it hard.
i only tried r22 a few times then back to r290. It was reclaimed r22 so may have been contaminated though. fair amount of r22 with r290 gave some nice results though;) better than straight r290.
to know if your condenser is doing its job measure the temperature of the liquid line just after leaves condenser and before the drier, should be about 6k (subcooling) difference between the pressure chart value and what you measure
(to work out subcooling and supaheat values read here/
http://www.xtremesystems.org/forums/...eat+subcooling
Thanks that helps a TON!
rrrr got some problems with my first ss.
i got 240cm long cap the usual 0,7mm and 134 as freon. This is for 120 wat am i right? using the same size but charging with 404 i got 180watt
is my calculation right? teoretical at least!
greetings,
q
Keep in mind, as compressor gets warmer, high side goes up a little while low side climbs up slightly. This keeps compressor from overheating by giving it enough cooling to compressor. (well superheat stays even... and yes, I do tune my units with safe margin of superheat usually 12-15k) However, in my systems, unless compressor gets warm enough, it doesn't have it's best temp for actual load :P
Im planning on a 200w heat load with r290 and .028 captube. This would put it at 6 feet. Does that sound right? I could start at 10 and go down from there while testing.
That sounds about right.
6 feet? Sounds a bit short. Of course, depends on your other components. Which are..?
It seems short to me also. The longer the tube the lower the low side right? I'm making my condenser tomorrow. I have .28 captube and will post the pump specs later. Condenser is gonna have 2 rows that pass 13 times.and is 7 1/2" by 7". Not to bad for an eye shot.
6 feet is short in comparison to what? a 0.031" cap with r507?
I don't think 8 feet will be able to hold the load anymore. but maybe start with 8 feet and work down from there.
I agree with this, 240cm (8ft) is close to a good length of 0.028" when you use R507a or R402a. R290 likes it a little shorter. I would guess around 200cm of 0.028 would be pretty close to what will be ideal for you but to be safe you can start at around 240cm abd work your way down.Quote:
Originally Posted by Unknown_road
As said before, it also depends on the compressor and evap you use, my guess is based on usage of a NL11F (220v) or NF9FX (110v)
Can I go shorter since I'm running an accumulator?
Any idea how long captubes i need, first stage and second? Tube size is 0,79mm.
Cascade with two 1hp rotary`s. First stage maybe r402 or r410a and second etylen.
for first stage you could use a tvx if you want 'cause the load is pretty stabile and big enough.
otherwise I would start with 2,5-2,7meters of captube in both stages, maybe a little longer in second.
Hmm.. i have one Danfoss TX2 but it is only -40c and r22
Ok again. Can I go shorter since I'm running an accumulator?
Yes you canQuote:
Originally Posted by 2long4u
Start making your own field experiences man.
doesn't help efficiency though
Ok, can someone tell me why or if it would be bad to go with a shorter cap tube than needed? Seems like you have more head room the shorter your cap tube is (to a certain extent of course). I am thinking of starting a vap phase system this summer and having one of my buddy's dad charge it for me with whatever refrig is needed for my setup(evap going on either GPU or CPU)... would love to build a dual head until but that might be a bit hard for a first build.
Thanks!!
i have found a good article about refrigeration, also cap tube measures. Unfortunately it is in portuguese, but altavista can be your friend :
http://www.trocalor.com.br/apostilas/rac_01.zip
page 84.
regards.
First off, Great read, lots of information here. I appreciate it all :D
secondly...
I'm guessing it's because it's easier to make a captube shorter than longer.Quote:
Originally Posted by Eightballrj
Thanks!
Yup, trimming is a breeze, splicing.. yuck
so i was reading this over and if you had 10 foot of 0.028 for a 150 watt load on r404a/r507
and if you are to get a increase of 15 watts for every foot you remove then to get 300 watts would you not have to remove all the cap tube by this rule
which means that you shouldn't use .028 for 300 watt load eh?Quote:
Originally Posted by ruffus
that is funnyt hough:yepp:
Its not really an accurate rule, the best way is to simply try something from someone else, then tune around that.
i use 0.031 but i seen this rule and seen this problem and thought i might say something about it
So I have 10 feet of .052 cap tube laying around... I am planning on about 150w load. Any way I can make this work?
Nope. Captube is cheap, buy .031 tube
bump
I'm not sure where I came across this article from Supco but a method is described using a balance gauge to determine if the cap tube length is sufficient of a restriction or not simply running the compressor on filtered air for just a few minutes to test, which can be done prior to charging..
http://www.supco.com/images/pdfs/Man...g%20Manual.pdf
I think there may be a few things wrong with the theory for our needs but what do I know, like we're testing and adjusting the cap tube with air which has very different flow characteristics then a fluid, a cold one at that! But I'm wondering if it's worth a shot?? Any ideas?
That was one of the few awesome articles I've read in a while. Quite good and a hand off to supco.
I'm glad it was a worthwhile read, wasn't sure how it applies in our scenario. I'm wondering if we could use a vacuum gauge instead of a flow meter??