one of our scientific techs is replacing a compressor and oil separator on this cascade ultra low freezer. he back flushes the entire low side system with a push pull system with 2 recovery tanks and r 12. dirty tank is on the left clean tank is on the right he isolates the incoming valve on the dirty tank and fills up the system with liquid then releases it into the dirty tank. removes all the oil and possible contaminants in the low side system. high stage is 404a low stage is 508b and a whiff of r 290 to keep the refrigerant oil viscous. pretty interesting stuff!

Posted by thetyshow at 2021-03-05 17:35:15 UTC