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Now how about -60C single stage from approx. 35C

Now how about -60C single stage from approx. 35C

Now how about -60C single stage from approx. 35C

(OP)
Hi,

Anyone know off hand the complement of components used in modern single-stage freeze dryer and vacuum trap type units? What is the preferred refrigerant and oil complement? Are "special" compressors needed? I have older units that achieve -60C quite easily
air-cooled at "room" temperatures. But the manufactures are tight-lipped about the composition of the new "cfc free" units. I have several of these (older ones) but for some reason the one here on site is missing it's charge label. It uses a Danfoss FR7.5B, which is geenrally considered an R-12 compressor but I'm not absolutely sure it uses R-12.  Also if anyone is familiar with manufacturers of very small compressors I would appreciate a pointer. My application requires very little lift at -60C, originally I had planned on going with thermoelectric coolers but they are so inefficient from a COP standpoint that I would be remiss not to look into a phase change system. Designing for production of about 100 units/year.

-Jeff

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