Ah very true, I guess thats another major problem with this many cap tubes. Have you considered after brazing up all the stages high pressure blasting some compressed air or nitrogen through the highside to remove any problems?
I'd hate to see you dig into that foam
If you have a cooling question or concern feel free to contact me.
LOL! Exactly what I noticed yesterdayOriginally Posted by mytekcontrols
Anyway, not so good news. It looks so perfect right now...
So there could be even more from this unit ? Wow, that's great news.
Michael, if I could request a new experiment for you - Seems as you have an amazing selection of equipment and gasses, as well as you seeming to want to research into the whole autocascade subject. :P
A "drop in replacement" for a single stage. As cheap as possible. (In terms of both gasses and parts.) As small as possible. (Standard single stage case ?) About the same cooling power as an average single stage. More efficient than a single stage.
Think you can do it ?*Crosses fingers*
-Cheeky Andrew.
Heh I don't think thats a fair request!
That's got some serious cash involved.
If you have a cooling question or concern feel free to contact me.
Well maybe just work out that idea in theory
Or we should set up a fund
It's cheeky, so sorry for that. :P
But I think it depends upon his situation and how much he wants to research.
Also yes, it could just be calculated in theory.
Was just an idea. :P You don't get anywhere in life if you don't ask questions.
Wow so many questions, and so little time
Jack, yep I remember your comment about it being too cold. Probably what got me thinking more. At first I just attributed it to the R-600, which in a previous big unit test, had shown a tendency to make the first stage colder than using R-123 & R-22.
Shouldn't be a problem on keeping the foam looking nice. We do this sort of thing all the time with units that we are repairing. And most of the time the patching comes out pretty clean.
Actually what I should have done is charged the unit before foaming with some nitrogen and R22, ran it, and then checked each captube that it was indeed flowing. Especially with 0.031 ID which are easily blocked when brazing.
yngndrw... A very tiny autocascade (truly a "Mini-Me" unit); someday I just might do something like that, but for now I only have my heart set on completing the present project, and keeping you all informed as to the progress.
Michael St. Pierre
- Worked 15 years for Polycold Systems
- Now Self-Employed
- Manufacture Heat Load Controllers
- Also do contract service work on Polycold units
Side note: I usually don't respond to PM's or emails regarding the projects that I post in the forums. I feel it's much more fair to all, to answer questions within the forum topics themselves.
My cascade is still in the experimental stage, I was hoping other cascade builders could post some of their results to compare also.
1st stage still isn't as cold as I expected, but those were the figures as of the last time it was run.
@Nol, my load tester only goes as high as 225-230w, but as the cascade stands now, I don't think it could hold much more than that atm. Have a look at my results, she likes 100-150w the way it is, after that temps drops begin to get larger.
the ethylene in NZ is colderWhen in doubt about an unknown substance, I taste it just in case it's pie.
Hehe.BTW, what is a DB
DB is a brand of beer.
Ha found it on youtube
The three guys at the telly are dead NZ icons.
Bloody good ad if you ask me.
If there is dead refrigeration icons looking down on us from cloud 9, they'd be saying the same thing about you mytek.
the ethylene in NZ is colderWhen in doubt about an unknown substance, I taste it just in case it's pie.
Thanks for the DB, and yes, that is a funny ad on youtube
Well I began digging out the foam on the captube side yesterday evening. Ran the unit, and I think the problem might actually be poor flow on the 1st captube (coming out of Phase Sep #1). It kinda makes sense, since I had to almost double the R-600 to get decent suction cooling (must have flooded over the top of Phase Sep #1).
Recovered the charge, and put it on a vacuum pump. I'll back fill it with nitrogen today, and do some dissection to see what i can find.
Stay tuned for some pics and more info as I proceed.
Michael St. Pierre
- Worked 15 years for Polycold Systems
- Now Self-Employed
- Manufacture Heat Load Controllers
- Also do contract service work on Polycold units
Side note: I usually don't respond to PM's or emails regarding the projects that I post in the forums. I feel it's much more fair to all, to answer questions within the forum topics themselves.
Oh wow, would not have guessed that. Will a normal vacuum pump get rid of butane? I'd imagine it must if it can get rid of water (dumb question I self answered, I must be out of it!). But are you ducting the fumes out? Whenever I work on a system that I've put propane in I have a piece of vinyl tube over the vacuum pump output to the outside of my workplace.
If you have a cooling question or concern feel free to contact me.
Good advice, and yes I made sure to do so
I checked the #1 captube, and everything looked good, but decided to shorten it to 30" for more flow. It was kinda tricky torching in the foam, but with a carefully positioned wet rag, every thing turned out OK.
I stuffed fiberglass insulation in the hole as a temporary patch until I am sure that I am done with all the modifications (covered with plastic and tape to serve as a vapor barrier).
Test results will be coming very soon.
BTW; the somewhat exposed copper tube to the right is part of the liquid line, and runs at or near room temperature.
Michael St. Pierre
- Worked 15 years for Polycold Systems
- Now Self-Employed
- Manufacture Heat Load Controllers
- Also do contract service work on Polycold units
Side note: I usually don't respond to PM's or emails regarding the projects that I post in the forums. I feel it's much more fair to all, to answer questions within the forum topics themselves.
Nice job. Do you make your own thermocouples? How are they bonded to the tubes?
If you have a cooling question or concern feel free to contact me.
Thanks Adam
Yes I make my own. Simply twist ends together for about 4-5 turns, pre-tin with 60-40 rosin flux solder, re-dip in flux, use micro torch to pre-tin area on copper with 60-40 solder (flux before hand), while heating --- immerse end of TC in pool of solder, and most important --- hold very steady while it cools.
Last edited by mytekcontrols; 04-08-2008 at 04:03 AM.
Michael St. Pierre
- Worked 15 years for Polycold Systems
- Now Self-Employed
- Manufacture Heat Load Controllers
- Also do contract service work on Polycold units
Side note: I usually don't respond to PM's or emails regarding the projects that I post in the forums. I feel it's much more fair to all, to answer questions within the forum topics themselves.
I was having problems with the R-600. Think it has to do with needing in-between gas such as R-290 (you guys did suggest this earlier).
Anyway for right now I went back to what I am used to working with: HCFC's for Liquid.
Here are the first test run results (No Load estimated as 25 Watts Static):
Last edited by mytekcontrols; 04-11-2008 at 05:35 PM.
Michael St. Pierre
- Worked 15 years for Polycold Systems
- Now Self-Employed
- Manufacture Heat Load Controllers
- Also do contract service work on Polycold units
Side note: I usually don't respond to PM's or emails regarding the projects that I post in the forums. I feel it's much more fair to all, to answer questions within the forum topics themselves.
Here are the Captubes now in use:
Michael St. Pierre
- Worked 15 years for Polycold Systems
- Now Self-Employed
- Manufacture Heat Load Controllers
- Also do contract service work on Polycold units
Side note: I usually don't respond to PM's or emails regarding the projects that I post in the forums. I feel it's much more fair to all, to answer questions within the forum topics themselves.
Aw dang.
Whats the green hose by the way? Still great results.
If you have a cooling question or concern feel free to contact me.
The green hose is connected to my addition tank (the small black tank to the left). Presently the other end is not connected to anything. But when I want to add either a gas, or a liquid to my running system, I would connect it to the gauge set and suck it in through the suction side.
Note: The addition tank is made from a suction accumulator, 0-200 psig gauge, 165 psig PRV, and a shut-off valve with 1/4" flare connection. Taking 75 psi from the tank - into the unit - equals approximately a 10 psi rise in the unit's static balance pressure.
BTW; I've had the unit running overnight --- will be doing load tests in a few hours.
Michael St. Pierre
- Worked 15 years for Polycold Systems
- Now Self-Employed
- Manufacture Heat Load Controllers
- Also do contract service work on Polycold units
Side note: I usually don't respond to PM's or emails regarding the projects that I post in the forums. I feel it's much more fair to all, to answer questions within the forum topics themselves.
![Send a message via AIM to [XC] gomeler](images/misc/im_aim.gif)
Excellent work Michael and damn cold temps for what was at one time an A/C unit
Load numbers are more important :P .
Can you describe the software you use and the controller for 9 probes?
I think it's a load tester that his own company makes, Mytek Controls.
Awsome job re-brasing and not melting the foam and thermocouple cables.
Can't wait to see the load test results.
Thanks Chris. I too am amazed at what this little sub 10cc compressor can do
Wait no longer, here they are:
Last edited by mytekcontrols; 04-10-2008 at 07:51 AM.
Michael St. Pierre
- Worked 15 years for Polycold Systems
- Now Self-Employed
- Manufacture Heat Load Controllers
- Also do contract service work on Polycold units
Side note: I usually don't respond to PM's or emails regarding the projects that I post in the forums. I feel it's much more fair to all, to answer questions within the forum topics themselves.
Reading the charge from the top of that one table, did you charge 4.5oz of R123, 3.5oz R22, and then whatever PSI you had after that, you added another 85 PSI to that worth of R170 and then another 85 PSI R14? Same for the Argon.
If so, wouldn't that make your static pressures go through the roof?
Opps! Slight error instead of 200 psig, it should have been 215 psig static Balance Pressure.
Edit: As it turned out, the static balance pressure when warmed-up, ended up being around 202 psig. I figure that at a +20C ambient, we could see as much as 205 psig.
The R123 and R22 liquids will have a combined vapor pressure of approximately 30-33 psig at normal room temperature. No I'm not kidding, the combination of the two liquids results in a vapor pressure less than R22 alone.
Add to this the combined gas pressure of the R170, R14, and Argon (182 psi), and you'll be somewhere between 212 - 215 psig total static BP.
I'll go upload a corrected test chart with the right BP.
Now the interesting part will be to see if the compressor can start-up with this high of a static pressure, without causing the motor to pull too many amps. If it does, I have 2 choices; increase the expansion tank volume, or add a buffer valve w/timer to bypass the compressor discharge into the existing expansion tank. I prefer the later, since it will allow me to keep my package size small.
Last edited by mytekcontrols; 04-11-2008 at 05:38 PM.
Michael St. Pierre
- Worked 15 years for Polycold Systems
- Now Self-Employed
- Manufacture Heat Load Controllers
- Also do contract service work on Polycold units
Side note: I usually don't respond to PM's or emails regarding the projects that I post in the forums. I feel it's much more fair to all, to answer questions within the forum topics themselves.
Different nature of the autocascade beast, I guess. Used to lower statics, like, 100psi, in single stages.
What do you mean you wonder if the compressor can start without drawing too many amps? Haven't you run it already?
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