Heat pump and refrigeration cycle

      Thermodynamic heat pump cycles or refrigeration cycles are the models for heat pumps and refrigerators. A heat pump is a machine or device that moves heat from one location (the 'source') at a lower temperature to another location (the 'sink' or 'heat sink') at a higher temperature using mechanical work or a high-temperature heat source. Thus a heat pump may be thought of a "heater" if the objectives is to warm an area , or a "refrigerator" if the objective is to cool an area ; regardless the operating principles are identical.