NOVELTY - An apparatus comprises a compressor including ionic liquid, to increases the pressure of the vapor of refrigerant; a condenser receives refrigerant vapor, and condenses the vapor under pressure to a liquid; a pressure reduction device receives liquid refrigerant, and reduces the pressure of the liquid to form a mixture of refrigerant in liquid and vapor form; an evaporator receives the mixture of liquid and vapor refrigerant, and evaporates the remaining liquid in the mixture to form refrigerant vapor; and a conduit that returns to the compressor refrigerant vapor.    USE - As an apparatus such as refrigerator, freezer, ice machine, air conditioner, industrial cooling system, heater or heat pump, for temperature adjustment (claimed).    ADVANTAGE - The ionic liquids as lubricants that are well suited for use in conjunction with the current and new refrigerants that are used in a vapor compression system. The lubricants increase the operating lifetime of vapor compression systems. The ionic liquids with refrigerants in a vapor compression system, have a balance of properties that is superior to that of the current synthetic lubricants.    DETAILED DESCRIPTION - An apparatus comprises a compressor that increases the pressure of the vapor of at least one refrigerant, where the compressor comprises moving parts that are lubricated by at least one ionic liquid; a condenser that receives refrigerant vapor that is passed out of the compressor, and condenses the vapor under pressure to a liquid; a pressure reduction device that receives liquid refrigerant that is passed out of the condenser, and reduces the pressure of the liquid to form a mixture of refrigerant in liquid and vapor form; an evaporator that receives the mixture of liquid and vapor refrigerant that is passed out of the pressure reduction device, and evaporates the remaining liquid in the mixture to form refrigerant vapor; and a conduit that returns to the compressor refrigerant vapor that is passed out of the evaporator; where a refrigerant is mixed with at least one ionic liquid. An INDEPENDENT CLAIM is included for adjusting the temperature of an object, medium or a space involves: (a) providing a mechanical device having moving parts to increase the pressure of the vapor of at least one refrigerant, and providing at least one ionic liquid to lubricate the moving parts of the device; (b) condensing the refrigerant vapor under pressure to a liquid; (c) reducing the pressure of the liquid refrigerant to form a mixture of refrigerant in liquid and vapor form; (d) evaporating the liquid refrigerant to form refrigerant vapor; and (e) repeating step (a) to increase the pressure of the refrigerant vapor formed in steps (c) and (d).    DESCRIPTION OF DRAWING(S) - The figure shows a schematic diagram of a simple vapor compression cycle.