Air-conditioning and hot water supply combination system

An air-conditioning and hot water supply combination system, comprising:

• one or a plurality of use units each equipped with at least a use side heat exchanger;
• one or a plurality of hot water supply units each equipped with at least a hot water supply side heat exchanger;
• one or a plurality of heat source units connected to the use units and the hot water supply units, each heat source unit being equipped with a compressor, a heat source side heat exchanger, a heat source side pressure reducing mechanism, and a receiver;
• and
• one or a plurality of branch units connected to the use units, the hot water supply units, and the heat source units, each branch unit being equipped with a use side pressure reducing mechanism that controls the flow of a refrigerant flowing into the use unit in accordance with an operation state in the use unit, and a hot water supply pressure reducing mechanism that controls the flow of the refrigerant flowing into the hot water supply unit in accordance with an operation state in the hot water supply unit,
• wherein when an evaporating pressure or an evaporating temperature calculated from the evaporating pressure reaches a first predetermined value or higher, the degree of superheat on the gas side of the heat source side heat exchanger or the degree of superheat on the gas side of the use side heat exchanger is controlled by the opening degree of the heat source side pressure reducing mechanism or the use side pressure reducing mechanism, such that the evaporating pressure or the evaporating temperature calculated from the evaporating pressure is less than or equal to the first predetermined value, and
• wherein when a condensing pressure or a condensing temperature calculated from a discharge pressure of the refrigerant discharged from the compressor reaches a second predetermined value or higher, the degree of subcooling on the liquid side of the hot water supply heat exchanger is controlled by the opening degree of the hot water supply pressure reducing mechanism, such that the condensing pressure or the condensing temperature calculated from the discharge pressure of the refrigerant discharged from the compressor is less than or equal to the second predetermined value.

An air-conditioning and hot water supply combination system, comprising:

• one or a plurality of use units each equipped with at least a use side heat exchanger;
• one or a plurality of hot water supply units each equipped with at least a hot water supply side heat exchanger;
• one or a plurality of heat source units connected to the use units and the hot water supply units, each heat source unit being equipped with a compressor, a heat source side heat exchanger, a heat source side pressure reducing mechanism, and a receiver;
• and
• one or a plurality of branch units connected to the use units, the hot water supply units, and the heat source units, each branch unit being equipped with a use side pressure reducing mechanism that controls the flow of a refrigerant flowing into the use unit in accordance with an operation state in the use unit, and a hot water supply pressure reducing mechanism that controls the flow of the refrigerant flowing into the hot water supply unit in accordance with an operation state in the hot water supply unit,
• wherein when an evaporating pressure or an evaporating temperature calculated from the evaporating pressure reaches a first predetermined value or higher, the degree of superheat on the gas side of the heat source side heat exchanger or the degree of superheat on the gas side of the use side heat exchanger is controlled by the opening degree of the heat source side pressure reducing mechanism or the use side pressure reducing mechanism, such that the evaporating pressure or the evaporating temperature calculated from the evaporating pressure is less than or equal to the first predetermined value, and
• wherein when the difference between an outside air temperature and the evaporating temperature is less than or equal to a fifth predetermined value during operation in which the use side heat exchanger functions as a refrigerant evaporator, the hot water supply heat exchanger functions as a refrigerant condenser, and the heat source side heat exchanger functions as a refrigerant evaporator, the opening degree of the heat source side pressure reducing mechanism is set to be less than a predetermined value or fully closed such that an exhaust heat full recovery operation is performed.