Polyolester oil, commonly called POE oil, is a type of Synthetic oil used in refrigeration compressors that is compatible with the refrigerants R-134a and R-12[1]. USE- The use of this type of oil is in the process of being phased-in by manufacturers who use compressors in their products. The need to replace the old oils has arisen due to environmental restrictions causing incompatibility of the old oils with the new refrigerants. POE oils are very good solvents and easily dissolve most of the residual mineral oils that they may be replacing. So even though small amounts of the old oil may remain, it won't clog the system. Problems- However, the same properties that make it a good solvent for oils also make it a good solvent of undesired things left behind during the manufacturing of a unit. Some of which are: dust, dirt, residue from soldering, small bits of metal from cutting, and oxidized metal from the tubing. The residues collected can clog the system filters and cause excessive wear or damage to critical components such as the vanes or valves. This aspect makes it more important to check that components are machined properly, deburred, and cleaned.
