Search:

Wow! Great work indeed!

Co2 is not a good choice here because it will, just like water, freeze on your evaporator (dry ice) if you go below -78?C. Nitrogen is what you should use...

Yeah I tried it back in 2009: http://www.extremecooling.de/forum/threads/1982-Verfl%C3%BCssigerverkleinerung Here you can see how it looked before:...

You have every symptom I know which indicates a too restrictive orifice - trust me on that!
Probably some parameters changed (ambient temp, "oil/refrigerant saturation", different load, different...

Which refrigerant (I suppose R404A) and whats you suction pressure?
The high subcooling indicates an overcharge. Low evaporation temps, lack of power and high superheat indicates not enough mass...

Yeah nachtfalk, I checked another LG pdf an your right :) . Und wo ich sehe das du aus Deutschland kommst, bist du auf extremecooling angemeldet? Falls ja dann verrat mir doch dein Usernamen dort ^^...

I attached the datasheet, have a look.

Nice results. You will get even better results if you pipe your unit like its shown in Kevins flowchart....

The normal way to fill a system with an expansion valve and a receiver is to start with a initial guess (i'd say 500g with your system...) and then beginn to apply load and check the sightglass!...

Hey Bartx,

I would also advice to change some more things:
1) Suction gas coming from the evaporator should also pass the plate hx!
2) The suction gas coming from the evaporator should now go...

May I ask you to explain this further?

Hey Kevin!
Great to see proper industrial stuff here! Whats the purpose for this unit? Seperating co2? Will it be a conventional cascade or will it be an autocascade :) ?
What typ of heat...

You better buy a well-designed, powerful cascade instead of a LN2 generator :D .

Hey Stewie,
I'm impressed by the building quality - this is by far the nicest work I've seen so far from an (non-professional) american builder :) ! BIG UPS!
Whats the reason you decided to build...

http://s14.directupload.net/images/130517/8s2fehsl.png
Hey Kevin!
This is how I do it. You have to upload your pictures somewhere else, e.g.: http://www.directupload.net/ .
After uploading the...

You have several options:
1a) Rewire the whole unit: Buy a small (like 20W) 12V PSU for the fans and wire 110V to the PSU and compressor. Then you don't have a thermometer but this is the cheapest...

Say what?!

I never used a spring bender, but I can't imagine that they work good.
Generally (assuming that I calculated it correctly: 3,5"=89mm) I don't think you will be able to bend a 1/2" pipe into such a...

Best method: Buy a proper pipe bender! If you don't have one and don't wanna spend money, annealing the pipes does help alot - but they will also fold more easily, so be very careful!
And try to...

R50 :D :rofl:

Looks brilliant Peter!
Do you pipe the captube to the top or to the bottom?

Remember, your first and second stage compressors have both 16ccm. So -30°C sounds absolutly normal for me.

Sounds okay for 2x 16ccm rotarys :) .
What temperatures show your first stage at load?

Why not using a plate hx if you want to chill water :) ?

Inverter AC... so they run with a frequency changer. Normally you can run them from 30-200hz.
The "controll units" you see have such a frequency changer/inverter inside.