Refrigeration cycle system, and method of operating the same

摘要

A new refrigeration cycle system, using a second coolant and a second lubricating oil, is formed adopting extension pipes and/or a indoor unit employed in a former refrigeration cycle system using a first coolant and a first lubricating oil. A lubricating oil storage apparatus is provided in the now refrigeration cycle system. While refrigerating cycle operation is being performed, the first lubricating oil still remaining in the extension pipes and/or the indoor unit is consecutively stored into the lubricating oil storage apparatus in a portion of coolant. The first coolant maybe a chlorofluorocarbon-based or hydrochlorofluorocarbon-based coolant, and the first lubricating oil may be mineral oil or alkylbenzene oil. The second coolant is preferably a hydrofluorocarbon-based coolant, and the second lubricating oil is preferably ester or ether oil.