Printable View
Well... we can try the cap tube pinch strategy, but keep in mind that it is difficult to unpinch the tube. I would want to use something that gives us a precision pinch. Maybe something like a small vise, so that we can pinch it very gradually.
The condenser is big enough to take the resulting liquid backing up into it (from the overcharge), so that shouldn't be a problem.
I actually have a small vise and it is sitting next to the system in the basement for tommorrow!
From pinching it what kinda gain can be expected?
And can someone please explain to me exactly how that works? I understand it creates some sort of backup..but i don't understand how that can create "more" evaporation or colder temps from the evaporation.
I think i am gonna use Jamal's idea of putting something in there to take alot of room up so i can use less fluid..less coolant shoudl equal colder temps shouldn;t it..i mean then the evap has less to cool and can get what is there cooler.
Any other ideas?
Looking back at your post, I see that you said -4F (-20C), not -4C. Okay, I'll buy that. :DQuote:
What dont you believe about the new thermometer? Do you think it is lower or higher then that?
And I recommend that you calibrate your old thermometer to match the new one.
lol....yea...-30F is my goal now i guess
I try to avoid making predictions, as there is a crack in my crystal ball.Quote:
From pinching it what kinda gain can be expected?
lol...well instead of a prediction..is there an educated guess that can be made?Quote:
Originally posted by Gary Lloyd
I try to avoid making predictions, as there is a crack in my crystal ball.
While we are pinching the cap tube, we need to monitor the coolant temp and the suction line temp a few inches from the compressor.
My SWAG (Scientific Wild Assed Guess) is -40C.
Sorry for my noobness, but what kinda monitoring should i do..is there anything in specific i should watch for?Quote:
Originally posted by Gary Lloyd
While we are pinching the cap tube, we need to monitor the coolant temp and the suction line temp a few inches from the compressor.
And one more question before I call it a night and let all this knowledge sink in...how should i go about pinching it...a VERY tiny bit at a time..montiro and then move on? How do i know when enough is enough...id like to have a general outlook as to what to look for before i go to far?
Less coolant wont get you colder ,It will get you cold faster.Quote:
Originally posted by Conflict
I think i am gonna use Jamal's idea of putting something in there to take alot of room up so i can use less fluid..less coolant shoudl equal colder temps shouldn;t it..i mean then the evap has less to cool and can get what is there cooler.
Any other ideas?
well...considering i already get to my maximum(coldest) temps in just a few hours i don't think that is an issue for me thenQuote:
Originally posted by jamaljaco
Less coolant wont get you colder ,It will get you cold faster.
Mine will pull down to its lowest in 40 min
Quote:
Originally posted by jamaljaco
Mine will pull down to its lowest in 40 min
well i guess i am making a guess...i also have 2 1/2 times asmuch fluid as you!
I have never pinched a cap tube, but yes, I would pinch it a very tiny bit at a time, and then wait for about 15 minutes to view the results. The coolant must be at its lowest temp before we start. And several pinches are better than one big pinch. I want the suction line temp to be about 10C higher than the coolant temp, and I want the bottom of the compressor to be warm.Quote:
And one more question before I call it a night and let all this knowledge sink in...how should i go about pinching it...a VERY tiny bit at a time..montiro and then move on? How do i know when enough is enough...id like to have a general outlook as to what to look for before i go to far?
So measuring the temp of the piping a few inches from the compressor...when i see the temps are about 10C warmer then the coolant...that is when it will be optimal?Quote:
Originally posted by Gary Lloyd
I have never pinched a cap tube, but yes, I would pinch it a very tiny bit at a time, and then wait for about 15 minutes to view the results. The coolant must be at its lowest temp before we start. And several pinches are better than one big pinch. I want the suction line temp to be about 10C higher than the coolant temp.
Sorry for all the basic questions..i am just a person of detail..want to do it one time and do it right!
No, optimal is when we do it right. The best we are going to get with the pinch method, overcharge, and no gauges, would be ballpark. Keep in mind that each pinch takes time to take effect.Quote:
So measuring the temp of the piping a few inches from the compressor...when i see the temps are about 10C warmer then the coolant...that is when it will be optimal?
OVercharge? Do you still really think the system is overfull of refrigerant?Quote:
Originally posted by Gary Lloyd
No, optimal is when we do it right. The best we are going to get with the pinch method, overcharge, and no gauges, would be ballpark. Keep in mind that each pinch takes time to take effect.
And yea it isn;t looking like i will be able to get any guages until I get back from florida.
I am just way into making due with what i have...so i want to tweak it with what i can for now....but i am gonna turn the system on in the morning...take temps of the coolant and the suction line after the system has been running for a hour or so...and then slightly pinch it..let it run for another hour or so and i will report the difference here.
TOmmorrow night here in northern mn gonna be -25F so I am gonna be overclocking a Pentium 4 system. Maybe i will have a great day and be able to fully clock a AMD and Intel...lol
Nope ,no accumulator, I do have a nifty series of humps in my suction line from all the bending, My compressor runs 108f system loaded after pulldown,with the ambient at 72f, its around 12f degrees warmer during pulldown in the same conditions.Quote:
Originally posted by Gary Lloyd
More importantly, the compressor isn't safe from floodback. I'm thinking your system has an accumulator in the suction line. That is the device that is saving your compressor. I don't recall seeing one on conflicts's system.
Also, I see it says in your profile you authored a book....
I am extremely interested in learning ALL about refrigeration. I am a seriously fast leanrer and i am always taking up a new interest and since playing with this over the last week I believe along with computers I have foudn somethign that really truly sparks a GREAT interest in me. If you could help me out and point me towards the best data or info to get started in learning the basics and semi advanced basics of refrigeration...i would greatly appreciate it
The lower the evaporator temp, the less refrigerant is needed. Your A/C is charged for above freezing evap temp. Yes, it is overcharged, and will be more so when you are finished pinching it.
Another thing to keep in mind: A pinch is a weak spot, which can snap if it is knocked around. When we are done, we want to strap the pinched area to the suction line, so that it doesn't get moved around and snapped.
Actually, I have authored 4 books. They are written in plain english where possible. I would recommend first going to:Quote:
Also, I see it says in your profile you authored a book....
http://refrigerationbasics.com
By the time you read through the samples, you will be ready for my book(s). I am retired and if I sell a few books I get to eat, so please hurry. I am fading fast. :D
The temperature in compressor heaven is 140-160F/60-70C, but 108F is well out of the danger zone. :DQuote:
My compressor runs 108f system loaded after pulldown,with the ambient at 72f, its around 12f degrees warmer during pulldown in the same conditions.
What is the temp on the bottom of the compressor at lowest coolant temp, while unloaded? This is where flooding is most likely.
ok just checked the compressor bottom was 93f with an ambient of 73f. The rest of the compressor is around 2f cooler than the bottom.Quote:
Originally posted by Gary Lloyd
What is the temp on the bottom of the compressor at lowest coolant temp, while unloaded? This is where flooding is most likely.
Hey Gary, is it true that when you get old there is little need for sleep?
hey Gary, always remember
Semper Ubi Sub Ubi :D ;)
As a lifelong insomniac, I can truthfully say that I have no idea. How much sleep I need, and how much sleep I get have always been entirely separate questions.Quote:
Hey Gary, is it true that when you get old there is little need for sleep?
I don't actually understand latin. The little tidbit in my sig is just something I picked up along the way. It makes me sound smarter than I actually am.Quote:
hey Gary, always remember
Semper Ubi Sub Ubi
docendo discimus = Learn by teaching
Well my cousin was over today and told me that I need to set the condensor up better so that it is getting more of the air from the fan, i need to get the evap to at least a 30 degree angle, and that i need to restrict flow a tad bit, I told him that you guys had already told me to pinch the lines a bit and he said that should work and that with a 4/5 HP compressor that -45C shouldn;t be out of the question
Gary,,,,my phrase is something that I'm sure you heard often from your mother.....Quote:
Originally posted by Gary Lloyd
As a lifelong insomniac, I can truthfully say that I have no idea. How much sleep I need, and how much sleep I get have always been entirely separate questions.
I don't actually understand latin. The little tidbit in my sig is just something I picked up along the way. It makes me sound smarter than I actually am.
docendo discimus = Learn by teaching
Semper Ubi Sub Ubi = Always Where Under Where (literal translation!) lol ;):D lol
Works for me. :DQuote:
Well my cousin was over today and told me that I need to set the condensor up better so that it is getting more of the air from the fan, i need to get the evap to at least a 30 degree angle, and that i need to restrict flow a tad bit, I told him that you guys had already told me to pinch the lines a bit and he said that should work and that with a 4/5 HP compressor that -45C shouldn;t be out of the question
Sage advice, which I have always ignored at every opportunity... LOLQuote:
Gary,,,,my phrase is something that I'm sure you heard often from your mother.....
Semper Ubi Sub Ubi = Always Where Under Where (literal translation!) lol lol
Well i have some stuff to do this afternoon and then i am going to get on the ball and provide MANY tempertures for you...lol
Cool. :D
LOL,,,TMI.....;)Quote:
Originally posted by Gary Lloyd
Sage advice, which I have always ignored at every opportunity... LOL
Well Conflict, hows it going?
i got way behind today and haven;t even had a chance to take any temps....gonna have to wait till tommorrow
darn ,see ya then.
yea bad day all around man! Blew up my Nvidia 5600 and my connetoc thingy for using one monitor keyboard and mouse on teo computers
LOL!!! If you don't mind me jumping in on the conversation!Quote:
Originally posted by GeekGoddess
hey Gary, always remember
Semper Ubi Sub Ubi :D ;)
I had a t-shirt made with that slogan just to P'off my latin teacher. She was older than dirt and had those thick cat like frames with a large jewlery chain running down and around her neck! Oh God was she hell!
Semper = always like semper fi being always faithful
Ubi = Where (as in the interrogative of Where is the beef)
Sub = under and in submarine literally meaning under water
Anyway, that is a first I have ever heard anyone else mention that phrase so I had to jump in. And, well.... you must be a geek then ;)
Taking one to know one :toast:
This sounds like our Geekgoddess.Quote:
Originally posted by kokoro_kara
She was older than dirt and had those thick cat like frames with a large jewlery chain running down and around her neck! Oh God was she hell!
***Ducking*** ***Running***
HEY!!!! I resemble that remark!!!:slap: :slapass: :p:
Hey Jamal....nice sig man...just noticed it!
LOL.... I have seen your pic.... not even close, but maybe in a thousand years ;) :p:Quote:
Originally posted by GeekGoddess
HEY!!!! I resemble that remark!!!:slap: :slapass: :p:
By the way, Great thread everyone. I am watching closely, my AC is on the Way!!!!
One question:
Are any of you going to use tec/peltiers. I notice, jamall mentioned it. I'm just really confused on if one would help at these temps.... I did just order a separate psu and 226 watt peltier.. guess I am wanting to go that route.??
Just curious,
K:toast:
thanks Dude, it took me some work ,I'm not all that familur with photoshop, Geek G helped with the fonts, had a hell of a time making them readable and not overpowering.Quote:
Originally posted by TheDude
Hey Jamal....nice sig man...just noticed it!
I think a 226w pelt would kick some serious butt with a chiller, I dont know the math though so all I can really say is try it . I thought about this myself. what psu by the way?Quote:
Originally posted by kokoro_kara
LOL.... I have seen your pic.... not even close, but maybe in a thousand years ;) :p:
By the way, Great thread everyone. I am watching closely, my AC is on the Way!!!!
One question:
Are any of you going to use tec/peltiers. I notice, jamall mentioned it. I'm just really confused on if one would help at these temps.... I did just order a separate psu and 226 watt peltier.. guess I am wanting to go that route.??
Just curious,
K:toast:
I have an old ac,r22, 5000btu unit. I was unable to bend the evap, so I (well, an AC technician friend) Cut the evap, resolder and recharge for only U$S20.
Now, the compressor runs too hot to touch it, and the line that return to the compressor isn`t frosting at all. I think I need some more refrigerant,What do you think Gary?
My pump is a Danner mag drive 7 , it runs really hot, so I put it out of the tank.
I saw someone got a mag5, and put it in the tank, do you think this will not stress the temps in the tank?
Sorry for my bad english, and thanks all of you guys, this thread is really theaching me a lot.
Hell If I Know, I'm just a NOOOOOOB :p: :shrug: :ROTF: And I'm having a blost :DQuote:
Originally posted by jamaljaco
I think a 226w pelt would kick some serious butt with a chiller, I dont know the math though so all I can really say is try it . I thought about this myself. what psu by the way?
Here a pic of it. I just got it off ebay with the Pelt... Here
we'll see if I jumped too deep to fast... but I'm having fun! I also got a PC Cooling & Power 510 deluxe on the way :bounces:
Right on man! Nice rig , got AC ? lol. thats the rig I had in mind.Quote:
Originally posted by kokoro_kara
Hell If I Know, I'm just a NOOOOOOB :p: :shrug: :ROTF: And I'm having a blost :D
Here a pic of it. I just got it off ebay with the Pelt... Here
we'll see if I jumped too deep to fast... but I'm having fun! I also got a PC Cooling & Power 510 deluxe on the way :bounces:
Cool jamaljaco, or better yet Damn Cool
:D
Hey, a note to Gary: Thanks for helping out, your knowledge is much appreciated and really rare (for the most part) for computer geeks!!
Thx
How cold does the coolant get? The suction line isn't going to frost at all until the coolant is below 0C, and shouldn't frost back to the compressor until the coolant is at its lowest temperature.Quote:
I have an old ac,r22, 5000btu unit. I was unable to bend the evap, so I (well, an AC technician friend) Cut the evap, resolder and recharge for only U$S20.
Now, the compressor runs too hot to touch it, and the line that return to the compressor isn`t frosting at all. I think I need some more refrigerant,What do you think Gary?
There has been a great deal of discussion about this. Pelts have a couple very serious drawbacks. As I understand it, the heat output on the hot side would be more than double the input, so this puts a very heavy load on the chiller.Quote:
I think a 226w pelt would kick some serious butt with a chiller, I dont know the math though so all I can really say is try it . I thought about this myself.
Also, I am told that it will not work below -50C on its cold side. If this were not the case, I think we would see pelts under every direct die block, despite their inefficiency.
It would make more sense to use an aircooled pelt to replace the condenser on a direct die system, thus making it the high stage for a cascade system, but then the problem is surface area. The small surface area on the cold side makes heat exchange extremely difficult. Possibly this could be done with many small pelts covering a large surface area.
Well i don't see the point of pelts if your getting temps to about -20...
Does that mean you could build a single stage system but charge it with a high pressue cascade low stage refrigerent and put the condenser in a chiller res?Quote:
It would make more sense to use an aircooled pelt to replace the condenser on a direct die system, thus making it the high stage for a cascade system, but then the problem is surface area. The small surface area on the cold side makes heat exchange extremely difficult. Possibly this could be done with many small pelts covering a large surface area.
Yes, but you better make damned sure the coolant in the res is very cold before the low stage compressor starts, and if that coolant warms up for any reason, the low stage compressor better shut off. This takes safety controls. You might want to take a look at DaBit's cascade. He has it covered every which way.
Also, there better be enough internal volume to hold down the static pressure.
If the pressure builds up too high: Best case scenario, the valves break inside your compressor. Worst case scenario, you find parts of your computer imbedded in the walls of your room, hopefully not soaked in blood.
:lol: Could a cascade 5 feet away from me literaly blow me into bits?
I know its probley not the greatest idea but I was just curious. I wouldent be stupid enough to do it :p:
Okay... I may be stretching it a little. Here is what I have actually seen: Compressor electrical terminal missing, little round hole through a block wall, with daylight peeking through. It sure looked like a bullet hole to me. I would not have wanted to be standing right there when it happened.
Can it actually explode? I have heard stories, but none that I could verify from personal experience. All of the cascade systems I have worked on had safety devices.
Well if you have every safety method in a cascade then it ain't gonna expload unless you do something really stupid.
I'd end up doing just that :stick:Quote:
Originally posted by kommando
Well if you have every safety method in a cascade then it ain't gonna expload unless you do something really stupid.
If you include enough internal volume in your cascade so that you keep the static charge at 250 lbs or less and have a highside mecanical relief device you will never have a problem. If it does not have enough gas add internal volume as you add gas. If the volume is added on th esuctionside the gas when off will fill the expansion tank and will be used when the system is running..
How about an update on how all these water chillers are working???
:D
Like...
What temps are you getting?
How often and how long are you running the chiller?
Has there been any unseen snags that have held you up?
How quiet are they and are there any methods of decreasing the noise?
What kind of mixtures for fluids are working the best?
And all the other questions answered that will help me write this book!!!! :banana: :banana: :banana:
What temps are you getting? -19C liquid -8C CPU idle at stock
How often and how long are you running the chiller? ran it all day before my mobo died
Has there been any unseen snags that have held you up? mobo died and 2 blocks leaked because of loose barbs before I got running :\
How quiet are they and are there any methods of decreasing the noise? there loud and I dont know how to quiet them
What kind of mixtures for fluids are working the best? I used windshield wiper fluid for mine but when I get my own built I'll use a 50/50 water/meth mixture.
Too bad about the Board :(Quote:
Originally posted by afireinside
What temps are you getting? -19C liquid -8C CPU idle at stock
How often and how long are you running the chiller? ran it all day before my mobo died
Has there been any unseen snags that have held you up? mobo died and 2 blocks leaked because of loose barbs before I got running :\
How quiet are they and are there any methods of decreasing the noise? there loud and I dont know how to quiet them
What kind of mixtures for fluids are working the best? I used windshield wiper fluid for mine but when I get my own built I'll use a 50/50 water/meth mixture.
Was their a reason behind the barbs leaking??? Just curious, if I should be concerned. One block is the danger den for the gpu with brass and the other is D'tek with plastic barbs for the cpu (this one I'm concerned about running chilled water).
Get metal barbs for it.
Well I guess they didnt come all to tight and putting the tubes and insulation loosened them... I put alot of tethlon tape on them and tightened them with a pair of pliers :D
Those are quite nice temps indeed, shame it busted before you got to see how hot it would go under load.Quote:
Originally posted by afireinside
What temps are you getting? -19C liquid -8C CPU idle at stock
How often and how long are you running the chiller? ran it all day before my mobo died
Has there been any unseen snags that have held you up? mobo died and 2 blocks leaked because of loose barbs before I got running :\
How quiet are they and are there any methods of decreasing the noise? there loud and I dont know how to quiet them
What kind of mixtures for fluids are working the best? I used windshield wiper fluid for mine but when I get my own built I'll use a 50/50 water/meth mixture.
I've got some car antifreeze here that goes down to -60C but it seems far too viscous to use and meanders pityfully along the tubing. Is there a set minimum speed for liquid flow through a block for efficient cooling ? Also, I would imagine this liquid does not abosrb heat as well as normal water so is less efficient.
Could someone tell me the normal operating temperature of a home freezer , is it -18C ? I am thinking of using an entire freezer as the chiller, rather than dismantling an air con unit. I imagine this will be less cold than a chiller, but more convenient spacewise than air con and cooler box
..and easier as well.
Regards
Andy
Household freezers are set to operate at -18ºC, but I dont know if they have the capacity to run a chiller. As they are so well insulated the heat load on them is quite small so they may only be rated for 150-200Watts, I think this may not be enough for your water chiller. I might be wrong, the worst that can happen is your fluid wont be as cold.
That's my thoughts as well, though the trade off is it is a simple first step into refrigeration, I can't imagine anything much simpler.Quote:
Originally posted by Russell_hq
Household freezers are set to operate at -18ºC, but I dont know if they have the capacity to run a chiller. As they are so well insulated the heat load on them is quite small so they may only be rated for 150-200Watts, I think this may not be enough for your water chiller. I might be wrong, the worst that can happen is your fluid wont be as cold.
I will still be able to use it for quick cooling of beer as well of course before the beer moves to my fridge.
Regards
Andy
Meh there ok. Probley gona give it another go today. Than start building my -30C chiller :D
Still waiting for many temps. :DQuote:
Well i have some stuff to do this afternoon and then i am going to get on the ball and provide MANY tempertures for you...lol
Pinching the cap tube, if done right, has a great deal of potential. It is a way of achieving much lower temps without breaking into the system.
Its going to be tricky, requiring patience. We need to walk someone through it.
Lower temps without buying anything? Sign me up :D
My freezer turned up yesterday and is somewhat bigger than Ithought, not sure if it will fit in the shed very well once my other stuff is in there. Anyhow it's a very cheap freezer and so has very cheap parts but it does get cold ! :) It uses R600a which I think is butane, I assume this is one of the cheaper R gases.
It actually works quite well, at 3 out of 5 on the scale i was at -19C and on fast freeze option the compressor runs all the time ( according to the manual ?! ) and it went down to -23.8C.
Now I have to dremel out some tunnels in the lid for the tubes and purchase the interior reservoir container ( something high tech like a plastic bucket.)
With this seemingly low cooling capacity system I'm going to have to take particular care stopping excess environmental warming on my tubes and blocks, even worse, I have gpu and cpu blocks in series...
Regards
Andy
I actually ended up breaking a line when i was moving everything....ive been to angry to post..lol....but i talked to chilly1 and i am gonna turn this into a direct die when i return from florida...so ill be back here in two months..you guys have a good one!Quote:
Originally posted by Gary Lloyd
Still waiting for many temps. :D
Pinching the cap tube, if done right, has a great deal of potential. It is a way of achieving much lower temps without breaking into the system.
Its going to be tricky, requiring patience. We need to walk someone through it.
The new freezer arrives.
http://www.aocb77.dsl.pipex.com/tempFeb2.jpg
I used the polystyrene foam that it was packed in to raise the lid so I could put channels in for the tubing ( see front left, also front right but hard to see. Foam is tapered front to back.
http://www.aocb77.dsl.pipex.com/tempFeb4.jpg
I know I am doing a good job as there is plenty of Duct tape ;)
Located a nice container for the liquid that will be in the freezer
http://www.aocb77.dsl.pipex.com/tempFeb3.jpg
It's a close fit as you can see below
http://www.aocb77.dsl.pipex.com/tempFeb5.jpg
My easy peasy "Dummies Chiller " is coming on well, the only downside is no room for beer cooling at present :( however I do have a back up fridge.
Regards
Andy
Put the beers in the chiller water, then give them a rinse when you take them out :D
1st beerQuote:
Originally posted by Russell_hq
Put the beers in the chiller water, then give them a rinse when you take them out :D
Wash off coolant and drink
2nd beer
wash off coolant and drink
3rd beer
wash off coolant and drink
4th beer
token effort at washing off coolant and drink
5th beer
drink
6th beer
start licking the can before drink
1st coolant
Put straw in coolant and suck the yummy cold blue liquid
2nd coolant
claim a break through for alcoholic science, go blind.
Regards
Thirsty
hey all with chillers
how long you have to run the chiller to get good temps
before you turn the pc.
iv seen lots of people running over night to get -20.
what are some expected temps to get for running a chiller running say 10mins before turning on, (starting off with room temp h20)
That's a much more difficult question than you might think. The fastest would be a chiller with a small reservoir, a big evaporator, a big condensing unit, and a TXV.Quote:
how long you have to run the chiller to get good temps
before you turn the pc.
In about 20 minutes I can boot my xp 2500+ @ 2500 mhz with -17c coolant temps after about 20 more minutes I can get her up to max clocks @ -25c coolant temps.Quote:
Originally posted by kayl
hey all with chillers
how long you have to run the chiller to get good temps
before you turn the pc.
iv seen lots of people running over night to get -20.
what are some expected temps to get for running a chiller running say 10mins before turning on, (starting off with room temp h20)
You wouldn't believe what a TXV would do for your chiller, Jamal. Like night and day.
Quote:
Originally posted by kayl
hey all with chillers
how long you have to run the chiller to get good temps
before you turn the pc.
iv seen lots of people running over night to get -20.
what are some expected temps to get for running a chiller running say 10mins before turning on, (starting off with room temp h20)
My chiller when running was chilling the liquid down to close to -20 within only an hour of use
ok, I'll bite , describe "night and day".Quote:
Originally posted by Gary Lloyd
You wouldn't believe what a TXV would do for your chiller, Jamal. Like night and day.
Well below -40C in a fraction of that time.
Geek Goddess and I have been busy building a shop in our basement so we will have a place to work on such things. I'm also looking to score another ac for her chiller and another for me so I don't have any downtime.Quote:
Originally posted by Gary Lloyd
Well below -40C in a fraction of that time.
I will have two complete systems, one to use and play on while the other is being modded in the shop.
Also, why TXV as opposed to cap tube?
A cap tube meters a fixed flow of refrigerant, removing a fixed amount of heat. A TXV opens up and provides a heavy flow, removing a lot of heat when the heat load is high (during pulldown), then tapers off as the heat load drops.
Its like the transmission on a car. The cap tube is like having one gear. The TXV is like having an automatic transmission.
Your chiller is currently in low gear. This gives you fast pulldown, but temps are not as low as they could be.
We can make the cap tube more restrictive. This would be like high gear. Slower getting there, but eventually lower temps.
The TXV gives you both faster pulldown and lower temps.
A TXV will respond to load and close as it gets colder maintaining superheat. This will allow it to get a lot colder than with a cap tube. Have you heard of the capacity / temperature trade off of a cap tube? Well with a cap tube you can have it colder but you lose capacity or you can have capacity and you lose temperature, With a TXV it will maintain a set superheat and a predesigned capacity through a sensing element(Bulb) connected to the discharge line of the evaporator.
Why dont you install 2 cap tubes, with the second controlled by a valve. Open the valve on start-up to give you greater capacity and quicker cool down times, then close it off to get the lower temps. This way you can change the flowrate without using a TXV, something to think about.
wouldn;t that be just as expensive as using a TEV?
Well after 20 odd pages of people bending tube and being far more adventurous than I could ever be, my own very easy to build and to be honest very heath robinson affair is taking form. Stop laughing at the back Gary, chilly1 and dabit.
You have to walk the walk not talk the talk ...... ;) OK, I am staggering :)
Now the disclaimers :D
1) My coolant sprung a leak tonight and covered the kitchen floor
2) I'm measuring all temps with a thermometer that is, although called Oregon Scientific, only as scientific as what NASA uses to measure the cooking food stuff in their cafe for lunchtime .
Right, here it is
http://www.aocb77.dsl.pipex.com/phase4ant0.jpg
spot purpling mess under chair ..oops
spot 1 metre of plumbers insolating tube on 3 metres or tube :D
http://www.aocb77.dsl.pipex.com/phase4ant6.jpg
The spare block is looking frosty so me thinks room temp has been broken ..yippee
But not by much if the turkey thermometer is to be believed !
http://www.aocb77.dsl.pipex.com/phase4ant1.jpg
-20C into the block -2C out .. maybe I should buy a Fluke ? :D
Stick it on my 80w Peltier
http://www.aocb77.dsl.pipex.com/phase4ant2.jpg
that's a bit better, have no idea what proper temps should be at this stage but obviously going in the right direction .
http://www.aocb77.dsl.pipex.com/phase4ant5.jpg
Double cascade will never beat that ;)
Regards
Andy
Red Green, eat your heart out. :toast:
Thinking most will not get the reference here. Red Green is the star of one of my all time favorite comedy shows, "The Red Green Show". What he can do with duct tape is a wonder to behold. His motto is, "If you can't be handsome, at least be handy".
Duct tape is amazing :O
Yer its great it has many abilities including taping people up to poles and leaving them there.Quote:
Originally posted by afireinside
Duct tape is amazing :O
GeekGoddess turned me on to red green! Its one of her faves.
Zakelwe , what you using for coolant? I'm also thinking a few bottles of vodka or higher prof alcohol might work better than the beer.
Also thanks for the TXV explanations guys it helps.
However I do forsee some potential problems with reaching -40C. Pump and tubing concerns. I can't test gear for -40C till I get there ,lol.
Cleaning out the paint shed at work the other day, I scored 10 gallons of straight ethyl alcohol denatured with Isopropyl, a lot less toxic than methyl alcohol, I also scored 5 gallons of pure methyl alcohol nasty stuff. Free is a very good price!
Damn i wonder what my idea will hit, hopefully -40 then the pump etc. problems.
Tygon will be fine at -40C I'd think as long as you dont touch it...
Pump is another problem. -40C would probley crack my Eheim 1250 after a few weeks and slaughter the flow rate. Not to mention I'd need like a 75:25 meth/water mix :banana4: :flame:
Nothing at all wrong with this strategy. There is a special place in my heart for ghetto systems. I love ingenuity.Quote:
Well after 20 odd pages of people bending tube and being far more adventurous than I could ever be, my own very easy to build and to be honest very heath robinson affair is taking form. Stop laughing at the back Gary, chilly1 and dabit.
Just a couple small drawbacks here. The compressor being small, it will take a while to get down to temp, and once the computer is running it will not be able to keep up, which means the temps will gradually rise. In the meantime, bypass the thermostat, and let's see how low it can go. :D
In addition to what Gary has said, it looks as though your coolant is sitting in a reservoir and not touching the evaporator pipes.So your primary cooling is the cold air around the plastic container.
Way way back I used a chest freezer and it couldnt hold 5c it worked so poorly.It was alot bigger than yours so I didnt have the option to fill it all the way up(only filled the bottom) but later I ripped the sheet metal off the sides and then just tie straped some copper pipes to the evaporator pipes and hit -20c in no time.By then I wasnt using it but I was starting to get into refrigeration at that point and had to play with it!I think you should check and see if it is water tight and if it is, fill the whole thing with your coolant.
Congratulations on getting it working and good luck.
Well I have a hangover this morning :sick:
Thanks for the tips guys, yes it's certainly not optimised yet that's for sure. I run 3dmark benching so 1 to 2 hours is all I need out of it, however being in a plastic container not really touching the side meant the time to get down to -20C for the liquid was 24 hours, mainly down to surface cooling of the liquid I guess.
The freezer is not waterproof so it will have to be a container, metal ideally, I will keep my eyes peeled. Sitting under the tub is 15m of copper 10mm tubing so I might atach the plastic pipes to go through that to precool the hot returning liquid before it goes back into the lake. However this is 10mm and so will need another pump in series to keep speed up. I'm not an expert in thermodynamics but I have the logical thought that a lot of cold metal surface area in contact with the liquid will be the reverse effect of the hot copper on the block touching the cpu. I guess my think is right , no???
Nice idea to go by the evap pipes , I'd be a bit concerned I might break one.. I'm a bit hamfisted and maybe couldn't get duct tape on fast enough before all the gas escaped :)
Gary, how do I bypass the thermastat ? Can I have fun and use a hammer, or is it more technical than that ?
Regards
Andy
There are two wires going to the thermostat. Put them together.
But unplug first. :D