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not when it's filled up with nitrogen and already have been vaccumed :PQuote:
Originally Posted by wdrzal
It has been sitting there leak testing for god knows how long.
Just missing relay for 2nd stage really :) Going to johnstone tomorrow to pick one up and wire it up. I could use the 1/2hp 3 in 1 to start but it is bit underpowered for compressor after all and don't want unpleasant things.
Well... got it vacuumed overnight and charged on 2nd stage. I don't like how first stage is behaving underload. In fact, it is SUCKING badly from what I can see under load.
I am surprised I got to this temp with 1st stage not even handling well. Going to have to try few things in 1st stage (thank god for txv with removable orifice and rotalock :P)
Just to get to belated -100c club :P
hehe great job Jinu117
now load teh b**ch :D
Hehe I wish. But I gotta get 1st stage done correctly first. There is at least 10-15c sitting here I am not getting thanks to first stage not working the way it should be. And finish up the insulation of course... lol.
What orifice you're using in your TXV? And you tried adjusting the superheat screw?
Those R508 looks like a really good gas for 2-stagers :)
Congratulations with beating the -100*c barier :toast:
Peter
Very nice jinu - now for some fun benches:woot:
Welcome to the -100C club:clap:
Hehe thanks RUNMC.
Benching will have to wait for my customer to show up once I do initial tuning with my load tester.
As for superheat screw... less you don't touch better it is. Orifice is mismatched clearly so I am doing pumping down (well done actually) and swapped orifice out. Vacuumming rest of channel before openeing up the valves and letting her run... :p
And it isn't R508 right now... I have some ethylene in there right now just to get to some intial tuning done and getting into -100c club really. It will be swapped to r508 afterwards :) when I am happy with first stage and swe what it can do with ethylene. Ethylene is cheaper after all and I never put reused gas in system - I don't vacuum over night to only to put even minscule of things back into system.
Eventually I will have to take this tanks to recycle center but I still have plenty of tank room... lol. (3 tanks of 30lbs... 1 for r404a, 1 for r402a, 1 for mix of junks really which I will have to pay off eventually).
Got the first stage working right... orifice was too big...
Considering how much i turned the knob... I could have used even smaller orifice... but oh well.
inlet -51c, outlet -48c, 2nd stage inlet... didn't look... i only have 2 uei dt200... lol. 2nd stage outlet -53c. This plate HX is very good as I expected from last few use.
2nd stage isn't as hot once I load tuned it. -85c 150w load, -83c 200w load.
Idle... -89c. Think cap tubing is too long and overcharged looking at the deltas. (150w here being x2 @ 1.75v dual priming from my experience, 200w... never saw cpu doing this before... lol)
Using 0.031 8ft 6 inches on this one. Think it is too long guys? (feels like it)
can't wait to drop by and see that baby in action.
its about time you got into the -100c club. what took you so long.
probably he wanted to do it safely and correctly and also only wants to sell non kaboom gas product
sweet work :D
Whats high and low side pressure in second stage? Seems that captube is too long, you should get about -100° or less idle and about -90° loaded.
Hey Jin,
Congrats on -100c club man
I knew you could do it :D
yeah i think it is too long myself too. 10/200 running. Way too overcharged from what I can see.Quote:
Originally Posted by cold_ice
Time to cut cap tubing tomorrow and continue on...
Pressures seem fine to me.
Quote:
Originally Posted by jinu117
that capillary length seem about right.
150w to 200 is quiet hot on a cascade.
Congrads on -100c hey
Nice job buddy!
Well bit of update is in order.
Reduced cap tubing down to 7ft 6inches this time based on my experience with cap tubing and load characteristics and also unseen's recommendation since this will most likely be R508 cascade in the end.
Major improvement in many ways.
#1. Idle temp is now at -107c :)
http://www.xtremesystems.org/forums/...1&d=1147504977
#2. Load 150w @ -95c, Load 200w @ -93c. Also discharge while fully loaded is only around 170-180 psi which makes me feel better about safety. When idling, very low discharge hehe...
http://www.xtremesystems.org/forums/...1&d=1147504977
gut feeling tells me i can reduce another 5-6 inches for even better temp but I am going to hold on till my experimental unit as this is for my customer :)
Going to wait to hear from him if he wants ethylene or r508 on his unit based on result. ;)
The compressor was oversized from start in case if he wants 3 stages in future and looking at the left over capacity of playing with, it sure would work just fine on 3 stages :)
http://www.xtremesystems.org/forums/...1&d=1147504977
http://www.xtremesystems.org/forums/...1&d=1147504977
Overinsulation on suction and HX... other than that... I really need to wrap up insulations on slhxs, txv, etc to get better temp... wonder how much are still hiden in temp wise for insulation.
Oh TXV used is danfoss TUAE for r404a/r507. Orifice #2. (this is smaller size than what most of you guys are used to...)
Jin, that's a monster you got going there!
This proves the solid first stage is a key to good evap temps:) What temp you got at the HX out while it was loaded? I'm guessing it was in way bellow -40c ;)
Thanks guys for cheering me :) I feel darned happy when you guys give me such a nice comment when just about all cascade pro here can do this :)
I noticed that when I was fine tuning today :)Quote:
Originally Posted by hatemi
HX out while 200w load was... gasp... -45c... I could have used R402a, etc for first stage but stuck to 404a since I figured it would be more than sufficient and I don't use r404a as often and have almost full tank (well... was almost full tank lol)
Probably could have netted few more degree by going r402a but I am running dangerously low on what I have until new tank gets in atm... :P
So many little things that could add up...
Hatemi, in your opinion... with 0.031... what would be right cap tubing for ethylene using... 3/4 hp compressor (:P)? I get the feeling about 7ft will be more optimal but don't really want to risk what I got... (I really don't like lengthening cap tubing)
In the end, considering this is my first cascade... I feel pretty happy :P
In I have used 150cm and bit over 2m captubes and the loaded temps were very close to eachother even tough the second stages compressors were different sizes(12cc vs 18cc) The one with 18cc and longer captube did have about 5c better noload temp, but when loaded with 180w they were pretty close (within 2c or so) to eachother.
amazing work there jinu,