Alternative to R508

[Shingoshi]

1. many
2.because it blocks the cap tube / evap, you should watch this vid it will expslane how co2 responds to mass pressure drop i.e hi pressure liqufied co2(captube before evap) to low pressure enviroment (evap suction side)
http://www.youtube.com/watch?v=4gVzL2pc0Gg

Man have you got me hooked on watching these YouTube videos!
By all means, keep them coming! I can't get enough of these.

So I need to find out what's the minimum pressure required to keep R-744 from icing. If I use R-744 as my first-stage and R-23 as my second-stage, maybe R-1150 could be low-temperature third-stage component for an autocascade.

Shingoshi