Re:CFCs? (Score 1)

MMM makes a line of flournerts that have a low GWP but the problem is that they are low pressure and very expensive. These are used for immersion cooling of large power electronic systems, like on a locomotive. We've played around with R134a and it IMHO works better because it is higher pressure and you can set the junction temperature of the chip by adjusting the system pressure. Like the 3M fluids R134a is a dielectric so will not damage the electronics. Single phase water reaches a point where it becomes impractical to take away more heat, the only way to control it is via flow or run it into a chiller. 2 phase systems go beyond that, breaking covalent bonds offers big thermal rewards.