A refrigerant pipe unit comprising: a first plate (51, 71); a second plate (52, 72) stacked on the first plate (51, 71); and a control valve (15, 21, 22, 17, 62, 63, 64), wherein one of or both the first plate (51, 71) and the second plate (52, 72) includes or include a refrigerant flow path, and the control valve (15, 21, 22, 17, 62, 63, 64) includes: a valve body (43, 44, 77, 88, 91) including a refrigerant passage (43a, 44a, 77a, 88a, 91a) communicating with the refrigerant flow path, the valve body (43, 44, 77, 88, 91) rotatably disposed in the first plate (51, 71), the valve body (43, 44, 77, 88, 91) configured to change a flow of a refrigerant at the refrigerant flow path, in accordance with an amount of rotation; and a driver (45, 78) configured to adjust the amount of rotation of the valve body (43, 44, 77, 88, 91); wherein the valve body (43, 44, 77, 88, 91) has an axial center of rotation (C1, C2, C3, C4, C5) extending in parallel with a normal direction of the first plate (51, 71); and characterized in that the refrigerant passage (43a, 44a, 77a, 88a, 91a) extends in a direction perpendicular to an axial center of rotation (C1, C2, C3, C4, C5) of the valve body (43, 44, 77, 88, 91), so that an inlet-side refrigerant flow path through which the refrigerant flows into the refrigerant passage in the valve body and an outlet-side refrigerant flow path through which the refrigerant flows out of the refrigerant passage in the valve body is arranged in a linear or planar form in a direction crossing the axial center of rotation of the valve body. a first plate (51, 71); a second plate (52, 72) stacked on the first plate (51, 71); and a control valve (15, 21, 22, 17, 62, 63, 64), wherein one of or both the first plate (51, 71) and the second plate (52, 72) includes or include a refrigerant flow path, and the control valve (15, 21, 22, 17, 62, 63, 64) includes: a valve body (43, 44, 77, 88, 91) including a refrigerant passage (43a, 44a, 77a, 88a, 91a) communicating with the refrigerant flow path, the valve body (43, 44, 77, 88, 91) rotatably disposed in the first plate (51, 71), the valve body (43, 44, 77, 88, 91) configured to change a flow of a refrigerant at the refrigerant flow path, in accordance with an amount of rotation; and a driver (45, 78) configured to adjust the amount of rotation of the valve body (43, 44, 77, 88, 91); a valve body (43, 44, 77, 88, 91) including a refrigerant passage (43a, 44a, 77a, 88a, 91a) communicating with the refrigerant flow path, the valve body (43, 44, 77, 88, 91) rotatably disposed in the first plate (51, 71), the valve body (43, 44, 77, 88, 91) configured to change a flow of a refrigerant at the refrigerant flow path, in accordance with an amount of rotation; and a driver (45, 78) configured to adjust the amount of rotation of the valve body (43, 44, 77, 88, 91); wherein the valve body (43, 44, 77, 88, 91) has an axial center of rotation (C1, C2, C3, C4, C5) extending in parallel with a normal direction of the first plate (51, 71); and characterized in that the refrigerant passage (43a, 44a, 77a, 88a, 91a) extends in a direction perpendicular to an axial center of rotation (C1, C2, C3, C4, C5) of the valve body (43, 44, 77, 88, 91), so that an inlet-side refrigerant flow path through which the refrigerant flows into the refrigerant passage in the valve body and an outlet-side refrigerant flow path through which the refrigerant flows out of the refrigerant passage in the valve body is arranged in a linear or planar form in a direction crossing the axial center of rotation of the valve body.