Refrigerator compressor oils

Your refrigerator's compressor uses special oil that must flow smoothly at temperatures as low as -40°C, far colder than any winter weather. This oil circulates with the refrigerant throughout the cooling system, so it needs to remain stable when mixed with chemicals that would dissolve regular motor oil. If the wrong oil is used, it can turn into a waxy sludge in the cold evaporator coils, blocking refrigerant flow and causing the refrigerator to stop cooling. Modern refrigerators using environmentally friendly refrigerants require synthetic oils specifically engineered to be compatible, as old mineral oils don't mix well with the newer coolant gases.