A refrigerant channel switching unit is disposed between a heat source unit and a utilization unit to switch flow of refrigerant in the refrigerant circuit. The refrigerant channel switching unit includes a first refrigerant pipe connected to a suction gas communicating pipe extending from the heat source unit, a second refrigerant pipe connected to a high-low pressure gas communicating pipe extending from the heat source unit, a third refrigerant pipe connected to a gas pipe extending to the utilization unit, a coupling portion, a first switch valve mounted to the first refrigerant pipe, and a second switch valve mounted to the second refrigerant pipe. The coupling portion is connected to the first, second and third refrigerant pipes. The First second and third are coupled through the coupling portion.