Abstract: An air-conditioner of a heat pump type includes a refrigeration cycle including an interior heat exchanger, an exterior heat exchanger, a compressor, a four-way valve, and an expansion mechanism, and a non-azeotrope refrigerant composed of not less than two kinds of refrigerants is used as a working medium. A refrigerant path in each of the interior and exterior heat exchangers is divided into a group of first refrigerant passages located at a region where a proportion of the liquid-phase refrigerant is large and a group of second refrigerant passages located at a region where a proportion of the liquid-phase refrigerant is small. At least part of the group of first refrigerant passages of each of the interior and exterior heat exchangers is located at the windward side. Heat transfer tubes of the group of first refrigerant passages of each of the interior and exterior heat exchangers are smaller in flow-passage cross-sectional area than those of the corresponding group of second refrigerant passages.

Abstract: A heat exchanger comprising fins and at least one heat transfer tube. An even number, not smaller than four, of louvers are severed and raised in an alternate and staggered manner with respect to a fin base line between the remaining adjacent fin base. Furthermore, the louvers raised on the same side with respect to the fin base line have heights defined by a line slanted at a constant angle in a stepped manner.