A refrigeration cycle apparatus comprising: a refrigerant circuit including a compressor, a condenser (14, 16), and an expansion mechanism (15, 15a, 15b), the compressor including a first member (32, 33) and a second member (33, 32), the first member (32, 33) and the second member (33, 32) being formed of steel, and being not surface-treated; the first member (32, 33) including a first contact portion (32a, 33a), the second member (33, 32) including a second contact portion (33a, 32a) being in contact with the first contact portion (32a, 33a) of the first member (32, 33) in a slidable manner; a refrigerant mixture inclusive of 1,1,2-trifluoroethylene and used in the refrigerant circuit; and a refrigerating machine oil that is free of phosphoric ester and used in the refrigerant circuit, and to which 2% or more by weight of an acid scavenger is added, wherein the steel of the first member (32, 33) of the compressor is exposed at the first contact portion (32a, 33a), the condenser (14, 16) includes a refrigerant flow path through which the refrigerant mixture flows, and when a portion from an inlet of the refrigerant flow path of the refrigerant mixture to 50% of a total length of the refrigerant flow path is defined as a first refrigerant flow path, and a portion of the refrigerant flow path downstream of the first refrigerant flow path in a refrigerant mixture flow direction is defined as a second refrigerant flow path, an expanded pipe portion is disposed on at least one of the second refrigerant flow path and a pipe between the condenser (14, 16) and the expansion mechanism (15, 15a, 15b), the expanded pipe portion having a greater flow path cross-section than the first refrigerant flow path. a refrigerant circuit including a compressor, a condenser (14, 16), and an expansion mechanism (15, 15a, 15b), the compressor including a first member (32, 33) and a second member (33, 32), the first member (32, 33) and the second member (33, 32) being formed of steel, and being not surface-treated; the first member (32, 33) including a first contact portion (32a, 33a), the second member (33, 32) including a second contact portion (33a, 32a) being in contact with the first contact portion (32a, 33a) of the first member (32, 33) in a slidable manner; the compressor including a first member (32, 33) and a second member (33, 32), the first member (32, 33) and the second member (33, 32) being formed of steel, and being not surface-treated; the first member (32, 33) including a first contact portion (32a, 33a), the second member (33, 32) including a second contact portion (33a, 32a) being in contact with the first contact portion (32a, 33a) of the first member (32, 33) in a slidable manner; a refrigerant mixture inclusive of 1,1,2-trifluoroethylene and used in the refrigerant circuit; and a refrigerating machine oil that is free of phosphoric ester and used in the refrigerant circuit, and to which 2% or more by weight of an acid scavenger is added, wherein the steel of the first member (32, 33) of the compressor is exposed at the first contact portion (32a, 33a), the condenser (14, 16) includes a refrigerant flow path through which the refrigerant mixture flows, and when a portion from an inlet of the refrigerant flow path of the refrigerant mixture to 50% of a total length of the refrigerant flow path is defined as a first refrigerant flow path, and a portion of the refrigerant flow path downstream of the first refrigerant flow path in a refrigerant mixture flow direction is defined as a second refrigerant flow path, an expanded pipe portion is disposed on at least one of the second refrigerant flow path and a pipe between the condenser (14, 16) and the expansion mechanism (15, 15a, 15b), the expanded pipe portion having a greater flow path cross-section than the first refrigerant flow path.