Abstract: A heat exchanger carries out heat exchange between a refrigerant that undergoes a phase change during heat exchange and another heating medium. The heat exchanger includes headers having the refrigerant flowing through interiors, a plurality of multi-hole first flat tubes, and a plurality of second flat tubes. The first flat tubes extend in a direction intersecting a lengthwise direction of the headers. The first flat tubes have a plurality of refrigerant flow channels with the refrigerant flowing through the refrigerant flow channels. The second flat tubes are stacked alternately with respect to the first flat tubes, with the other heating medium flowing through the second flat tubes. The headers are arranged to extend along a horizontal direction.

Abstract: A heat exchanger carries out heat exchange between a refrigerant that undergoes a phase change during heat exchange and another heating medium. The heat exchanger includes headers having the refrigerant flowing through interiors, a plurality of multi-hole first flat tubes, and a plurality of second flat tubes. The first flat tubes extend in a direction intersecting a lengthwise direction of the headers. The first flat tubes have a plurality of refrigerant flow channels with the refrigerant flowing through the refrigerant flow channels. The second flat tubes are stacked alternately with respect to the first flat tubes, with the other heating medium flowing through the second flat tubes. The headers are arranged to extend along a horizontal direction.