New Cascade System - Need Help With Design - PLEASE READ!!

[nolo200]

Hey guys! I hope there are still some big names viewing this forum. I need some help with a cascade design.

I plan to use R-507 for the first stage and R-508 for the second stage. I need as evap temp of -78C when the ambient is -18C when under a 430W load, I will design a custom evap. I'm basically just looking for a temp drop of 60C or greater at all temperatures between -18C and 38C. I'm also looking for a COP of about 0.9-1.0 or greater. An 18", 2550 cfm fan will be used on the condenser (Unless better option is available, this fan uses 141W). Fan usage is not included in the COP.

Evap pressure should be kept above 0.95 bar at all costs to prevent leakage.

Manufacturing cost has no limit per se, efficiency is key.

Anyone have any input?

[nolo200]

The evap will be similar in design to what a CPU overclocker would use.