Whats a good low temp compressor?
Printable View
Whats a good low temp compressor?
Nice going bowman :)
dont know whats up with the futuremark ORB not finding all R9700 scores but atleast my project manager has one 9700 @7.2k ;)
yea i know i ran it now is shows,,run again and it disappears...LOLQuote:
Originally posted by macci
Nice going bowman :)
dont know whats up with the futuremark ORB not finding all R9700 scores but atleast my project manager has one 9700 @7.2k ;)
but that was with my amd.the p4 will give me a alot higher score.
got 2 good chips here i just need time to play.
you wont,they have been discontinued.Quote:
Originally posted by JToolz
Hey Bowman, Where can I get a bristol compressor like the one that you have running the three evaps?
and finding a good low temp compressor will be expensive,but i dont know what to tell you .it is hit or miss.
i have spent lots of time and money just swapping out compressors until i found one to work it.it is hit or miss.
just like cascades.the proper low side refirgerant is normally something like r508b (95 )or r23,something along them lines.and the cost of that stuff goes way over $1000.us for a can of freon.
so these toys i have cost me lots.which at the moment i am not spending that to just play;)
anyways i havent been working this week in my shop much since i have beed swamped at work and at home.
i do have a mach II i am tring to finish up today.
and i did spend yesterday morning tearing down my cascade and make a new frame to hold the new version i am working on.
as it is a normal cascade,but i am making a few modifications which is not normal,but as always i dream up new things to try.i have been always lucky as i can design in my head and picture the outcome.then i just build them.
but it will be differant.:D
I like the Copelands, with Tecumsehs second. Danfoss is getting a very good reputation, also. There are many other brands out there that I am just not familiar with, so have no opinion.Quote:
Whats a good low temp compressor?
As a rule, all compressors are pretty rugged, but some more so than others. None are noob-proof. Common causes of failure are overcharging and charging with liquid. Systems should be vapor charged. The exception is zeotropic blend refrigerants (all of the 400 series refrigerants), which must be liquid charged. This should be done gradually, a small squirt at a time. Compressors are designed to pump vapor, not liquid.
Hi Gary, Hi Bowman :) This is a great thread.Quote:
Originally posted by Gary Lloyd
I like the Copelands, with Tecumsehs second. Danfoss is getting a very good reputation, also. There are many other brands out there that I am just not familiar with, so have no opinion.
I have become particularly attached to the Tecumseh "TPA" model of compressors in the 850,950, and 1050 btuh range, rated at -10F R-134A. I use R-404A for a -50F to -60F evaporating temperature application.
I suggest using any compressor rated R-134A for -10F or -20F (low temperature), and using R-404A for the temps we are trying to acheive here, -50F. This is a common practice in the commercial Ice Cream Cabinet industry. ;) My experience is, select the capacity at the R-134A rating at twice the design load @ -50F.
Also, Bowman - I was doing some figuring, and came to the conclusion that in the three evaporator application, that a Sporlan NIS(E)-1/8-ZP expansion valve would be a perfect selection for a three evap system, assuming a 150w load for each evaporator. :toast:
Cheers
Welcome to Xtreme herefishy! :D
:toast:
You sound like you know your stuff...stick around and help the rest of us out. :D
welcome aboard herefishy:toast:
glad to see you make it over to this neck of the woods.:D
well i have tried a couple tev valves,and on these systems they dont work.the temps change too quicky for a tev to adjust to the load or no load,so you get a starve condition at times,and that starts a chain reaction that is hard to control.too much refriegerant is boiling off before it enters the block so you dont get it where it is needed.man it would be nice if i could get one to work.would take alot of work off of me:D
Hey herefishy. How's it going? :D
What would you think of doing multiple evaps in series with a TXV?
Why would you prefer a R134A compressor over a R404A compressor? The valve ports may be tighter, but the valve reeds would be weaker, and the internal relief setting lower.
:toast: :smileysex :stick: :banana: :D :cool: :p:Quote:
Originally posted by Gary Lloyd
Hey herefishy. How's it going? :D
What would you think of doing multiple evaps in series with a TXV?
.... for the same reason that the ice cream merchandiser manufacturers prefer to do it that way. LOL! ... and I do it, and it works great.Quote:
Why would you prefer a R134A compressor over a R404A compressor? The valve ports may be tighter, but the valve reeds would be weaker, and the internal relief setting lower.
Actually, you will not find R-404A compressors rated for -50F. -50F - 60F is what we are trying to acheive. most '404 compressors and systems are rated mostly down to -30F, some down to -40F. These ratings get even rarer in the fractional horsepower department. As a mtter of fact, I cannot recall a 1/4hp compressor that I have seen specifically rated for -40F.
The low temp compressors that are rated for the (lower pressure) refrigerants seem to be very well adaptable to very low temperature applications with the (higher pressure) refrigerants.
:)
It must due to the valve porting. The downside would be the increased pressure on the high side.
I'm thinking Bowman should be about ready for a triple evap in series with a TXV. The combined load brings it in range for the smallest orifices. :D
I'm wondering which evap would be the most efficient. There would be flashing in the first, and superheat in the third. Would the most efficient be the center evap or the first evap?
Quote:
I'm thinking Bowman should be about ready for a triple evap in series with a TXV. The combined load brings it in range for the smallest orifices.
Bowman.... it's all yours.... mind you, you may have tried, "a couple of expansion valves", but there is only one with the proper capacity. :stick:
I came here to contribute something.... (to you)
:)
PS - but I might beat you to the punch... DOH! I don't mean to ruin your beautiful thread... I love it!... but Gary keeps egging me on.. :( ...... stop it!!!!! ;)
Cheers
That's called "hunting". It's caused by the orifice being too large for the heat load. With the heavier combined heat load of three evaps, this should hopefully pull it in range of the smallest orifice.Quote:
well i have tried a couple tev valves,and on these systems they dont work.the temps change too quicky for a tev to adjust to the load or no load,so you get a starve condition at times,and that starts a chain reaction that is hard to control.too much refriegerant is boiling off before it enters the block so you dont get it where it is needed.man it would be nice if i could get one to work.would take alot of work off of me
Baiting the hook. Playing out the line. "herefishy... herefishy"... LOL
Bowman has my book now. He will soon be thinking in saturation temperatures, dT's, TD's and such. :D
LOL! I don't think any one person could ruin this thread....it's loved by way too many ppl. :) I'm glad that you are contributing you expertise and your thoughts tho, they are truely welcome I believe.....and the thread is getting even better now! ;)Quote:
Originally posted by herefishy
PS - but I might beat you to the punch... DOH! I don't mean to ruin your beautiful thread... I love it!... but Gary keeps egging me on.. :( ...... stop it!!!!! ;)
Cheers
where can we find these units from herefishy?
sorry bud i havent had a chance to reply.:(Quote:
Originally posted by herefishy
Bowman.... it's all yours.... mind you, you may have tried, "a couple of expansion valves", but there is only one with the proper capacity. :stick:
I came here to contribute something.... (to you)
:)
PS - but I might beat you to the punch... DOH! I don't mean to ruin your beautiful thread... I love it!... but Gary keeps egging me on.. :( ...... stop it!!!!! ;)
Cheers
work is killing me latley.
not saying i havent thought about the valves...LOL i have,
and i do appreciate anything you can offer to help.
as i need all the help i can get sometimes.....:slobber:
dont know the name of a good shrink do ya?:D
to run a tev valve i would need to redesign the evap's for the larger tube intake,not like i dont have a case of adjustable valves setting in my room.with every offrice they make.so wouldnt cost me anything.i just need more time to test and experiment.
but i did start on the cascade again.so that is the next thing i am fixing.built the frame,electrical box with relays and lots of goodies.got it on wheels.trying to decied what refrigerant i am going to use in the high side.as i have 22,502,404 to pick from here.since the compressor i am using has mineral oil.i could use 22 or 502 or a mix of both,or could change the oil out and use 404.
Gary what you think on the high side refrigerant?
the low side....thats in the air right now.i have a can of co2 to test with,but i am worried about the triple point.i could easily try some 410 but not as cold, about $240 a can.or go ahead and order a can of 508b which would cost me $1100.
on the prommie front...... hobocrow i have yours running at -46c loaded cold and -44c loaded hot.so it is running about the same as the last mach II:D
bowman, woudlnt R410 have a too small pressure ? like 2bar max... :O
the problem would be finding a apropireate cap tube
but you could overcome this problem using a fuel pump on the exchangers outlet that would increase the pressure to like 10 bar.. :D
Hi Bowman,Quote:
Originally posted by bowman1964
Gary what you think on the high side refrigerant?
the low side....thats in the air right now.i have a can of co2 to test with,but i am worried about the triple point.i could easily try some 410 but not as cold, about $240 a can.or go ahead and order a can of 508b which would cost me $1100.
Didn't I see a post whereas you received a bottle of R-170 (ethane)? If your going to use R-170, you would want a 1st stage evaporating temperature of -10F to maintain a second stage head pressure of 173psi.... or +10F to maintain a second stage head pressure of 239psi. It would be a low or medium/low application, nonetheless.
What would be the ideal range for a R-170 pressure ratio, I wonder?:confused:
Hey! Where's CaptainCascade? :p:
What do you have a case of? Sporlan "Q" valves and orifices? The smallest "0" valve won't do it, it's rated at about .22 tons @ minus40F SST R-404A. You need a valve rated at about .11 tons. The best selection is the Sporlan 1/8 valve, of which I like the NISE-1/8-ZP. Externally equalized for sure!Quote:
Originally posted by bowman1964
....not like i dont have a case of adjustable valves setting in my room.with every offrice they make.so wouldnt cost me anything.i just need more time to test and experiment.
;)
Well ..berkut ...410 will work if you can put it in a deep enough vacuum but temps would only hit ...i am guessing around -65c on a slight load.it is just the cost is alot cheaper.
herefishy na....would be nice if i had a can of r-170 ,but i dont.
and you are so right about keeping the low side at a high enough condensing pressure to work right.but i will be able to adjust the high side with refrigerant to fine tune the evaperating temperture of the high side.this will allow me to change the condesing pressure of the low side....i hope:D
it's all about fine tuning.......damm i sound like Gary...i am feeling old LOL;)
Could try NOS, although similar triple point problems to C02 apparently although lower temps, looking at the phase diagram in the overclocking section for C02 looks like its a non starter anyway...
I found some ethylene at work, ive stashed it and going to see if any1 reports it missing ;)
]JR[
:thumbsup: Excellent...Tweak Miester!!:toast: :banana:
well not much going on here tonight other than i modded 2 radeon r9800's .got one to hit the magic 400 memory,and looks to do almost 450core on a stock heatsink.this one was a very low voltage one.left the factory with only 1.7v on the memory and 2.69 on the core.
I did bring in the cascade frame from outside.we are getting a nice hurricane i hear thursday,so i wont be doing alot but getting ready for the nasty bugger.i hope i only get rain and a few winds,but weather man seems to think differant.
got one prommie beside me running wide open full load in here making it really hot....:LOL:D
i know you guys like pics....i will post the cascade maybe.....i said maybe....this weekend..if i still have power and lights.
Congrats on the R9800's ....seems like you found one and you're on you way again! :)
That storm is just gonna dump a bunch of water on ya....I got fingers X'd and best wishes..If that is my prommie running now. ...turn it up, they are great room heaters! Take care! :toast: