Arrived to a call today to find one of the circuits (two scroll compressors) with what looked like water in the sight glasses. This system utilizes a water cooled shell and tube condenser. I have came across water in the refrigeration circuit several times, however I'm trying to find out exactly how this happens. In this case I found this on a maintance and the machine was not running on arrival. The refrigerant is 134A and this skid is used for DX high temperature (comfort cooling). The water pressure from the discharge of the condenser water pump is a constant 40 pound supply. So my question is this, if my refrigerant pressure stays higher then 40 pounds all the time how exactly does water enter into my refrigeration system. I was told that this is due to OSMOSIS. Can somebody tell me if this is true and exactly how this works. I have been looking into this, however mabey somebody can simply explain this to me.