The first testrun without any optimizations. High stage has not enough refrigerant (superheat almost 15K). The low stage has certainly not enough refrigerant; I just gave it a shot. Superheat at the compressor is more than 70K. But I admit that I must do accurate measurements. But that's something for the next session.



Interstage is -35C. This is measured at the TEV bulb, so it is heated a bit by the incoming hot ethylene. 'real' temp is probably lower. I cannot measure pressures at the moment since I have only one meterset.

Evaporator (unloaded) runs at -109C. This was 5 seconds before I pulled the plug. But as I said: it's a testrun.

Low stage pressures. Discharge pressure is a bit low IMHO. But, this is with too little refrigerant.



Next thing on the list is finishing the electrical interconnections (currently only the high pressure switch is connected, the rest is plugged directly in the wall outlets). Then, optimization of the high stage. And finally, optimization of the low stage, with load.

edit: a system overview of a few days ago. I promise I will shoot more detailed pictures and finish the article on my website. But burning copper is more fun than writing