did you skip open blasting?
even releasing 200PSI air from your solvent tank will cause the outlet to frost over.
yes, @PharmExOregon is correct, you really should know wtf you’re doing if you’re gonna use evaporative cooling to chill any part of your system…and @FicklePickle is also correct, it is a trick the pros use.
I for instance have run a couple of lbs of solvent into my vacuum jacketed columns and recovered that to chill them down before filling and soaking. I used the head pressure I gained by recovering to push the -70 solvent (no head pressure) out of my solvent tank.
Edit: @grawolf was kind enough to share the maths behind this trick. figured a crosslink was worth the edit. see: Recovery tank capacity - #38 by Graywolf