A heat exchange unit comprising: a heat exchanger including a plurality of heat transfer tubes; a first refrigerant distributor and a second refrigerant distributor, wherein the first refrigerant distributor includes an first inlet pipe through which refrigerant flows into the first refrigerant distributor, and a plurality of first distribution pipes through which the refrigerant flows out of the first refrigerant distributor, each of the plurality of first distribution pipes being connected to a corresponding one of the plurality of heat transfer tubes, and wherein the second refrigerant distributor includes an second inlet pipe through which refrigerant flows into the second refrigerant distributor, and a plurality of second distribution pipes through which the refrigerant flows out of the second refrigerant distributor, each of the plurality of second distribution pipes being connected to a corresponding one of the plurality of heat transfer tubes, and wherein an average value of levels of the plurality of the second distribution pipes connected to the plurality of heat transfer tubes is lower than an average value of levels of the plurality of first distribution pipes connected to the plurality of heat transfer tubes, wherein a level of a distribution pipe is a distance from a lowermost end of the heat exchanger to an axis of the distribution pipe in a top-bottom direction of the heat exchanger, and the heat exchange unit being characterized by that: an inside diameter of the second inlet pipe of the second refrigerant distributor is smaller than an inside diameter of the first inlet pipe of the second refrigerant distributor. a heat exchanger including a plurality of heat transfer tubes; a first refrigerant distributor and a second refrigerant distributor, wherein the first refrigerant distributor includes an first inlet pipe through which refrigerant flows into the first refrigerant distributor, and a plurality of first distribution pipes through which the refrigerant flows out of the first refrigerant distributor, each of the plurality of first distribution pipes being connected to a corresponding one of the plurality of heat transfer tubes, and an first inlet pipe through which refrigerant flows into the first refrigerant distributor, and a plurality of first distribution pipes through which the refrigerant flows out of the first refrigerant distributor, each of the plurality of first distribution pipes being connected to a corresponding one of the plurality of heat transfer tubes, and wherein the second refrigerant distributor includes an second inlet pipe through which refrigerant flows into the second refrigerant distributor, and a plurality of second distribution pipes through which the refrigerant flows out of the second refrigerant distributor, each of the plurality of second distribution pipes being connected to a corresponding one of the plurality of heat transfer tubes, and an second inlet pipe through which refrigerant flows into the second refrigerant distributor, and a plurality of second distribution pipes through which the refrigerant flows out of the second refrigerant distributor, each of the plurality of second distribution pipes being connected to a corresponding one of the plurality of heat transfer tubes, and wherein an average value of levels of the plurality of the second distribution pipes connected to the plurality of heat transfer tubes is lower than an average value of levels of the plurality of first distribution pipes connected to the plurality of heat transfer tubes, wherein a level of a distribution pipe is a distance from a lowermost end of the heat exchanger to an axis of the distribution pipe in a top-bottom direction of the heat exchanger, and the heat exchange unit being characterized by that: an inside diameter of the second inlet pipe of the second refrigerant distributor is smaller than an inside diameter of the first inlet pipe of the second refrigerant distributor.