A heat exchanger adapted to be used in a vapor compression system, the heat exchanger comprising: a shell having a refrigerant inlet that at least refrigerant with liquid refrigerant flows therethrough and a shell refrigerant vapor outlet, with a longitudinal center axis of the shell extending generally parallel to a horizontal plane; a refrigerant distributor extending longitudinally within the shell, the refrigerant distributor being connected to the refrigerant inlet and including a first portion connected to the refrigerant inlet to receive refrigerant from the inlet, the first portion having at least one first refrigerant liquid distribution opening and a first refrigerant vapor distribution outlet opening, a second portion connected to the first portion to receive refrigerant from the at least one first refrigerant liquid distribution opening, the second portion having at least one second refrigerant liquid distribution opening and at least one second refrigerant vapor distribution outlet opening (92a, 94a), characterised in that the first portion is configured such that the at least one first refrigerant vapor distribution outlet opening distributes refrigerant vapor into an interior of the shell before the refrigerant vapor exits through the shell refrigerant vapor outlet and the second portion is configured such that the at least one second refrigerant vapor distribution outlet opening distributes refrigerant vapor into an interior of the shell before the refrigerant vapor exits through the shell refrigerant vapor outlet; and in that a heat transferring unit is disposed inside of the shell below the refrigerant distributor to receive liquid refrigerant discharged from the second portion of refrigerant distributor supplied to the heat transferring unit. a shell having a refrigerant inlet that at least refrigerant with liquid refrigerant flows therethrough and a shell refrigerant vapor outlet, with a longitudinal center axis of the shell extending generally parallel to a horizontal plane; a refrigerant distributor extending longitudinally within the shell, the refrigerant distributor being connected to the refrigerant inlet and including a first portion connected to the refrigerant inlet to receive refrigerant from the inlet, the first portion having at least one first refrigerant liquid distribution opening and a first refrigerant vapor distribution outlet opening, a second portion connected to the first portion to receive refrigerant from the at least one first refrigerant liquid distribution opening, the second portion having at least one second refrigerant liquid distribution opening and at least one second refrigerant vapor distribution outlet opening (92a, 94a), characterised in that the first portion is configured such that the at least one first refrigerant vapor distribution outlet opening distributes refrigerant vapor into an interior of the shell before the refrigerant vapor exits through the shell refrigerant vapor outlet and the second portion is configured such that the at least one second refrigerant vapor distribution outlet opening distributes refrigerant vapor into an interior of the shell before the refrigerant vapor exits through the shell refrigerant vapor outlet; and in that a heat transferring unit is disposed inside of the shell below the refrigerant distributor to receive liquid refrigerant discharged from the second portion of refrigerant distributor supplied to the heat transferring unit. a first portion connected to the refrigerant inlet to receive refrigerant from the inlet, the first portion having at least one first refrigerant liquid distribution opening and a first refrigerant vapor distribution outlet opening, a second portion connected to the first portion to receive refrigerant from the at least one first refrigerant liquid distribution opening, the second portion having at least one second refrigerant liquid distribution opening and at least one second refrigerant vapor distribution outlet opening (92a, 94a), characterised in that the first portion is configured such that the at least one first refrigerant vapor distribution outlet opening distributes refrigerant vapor into an interior of the shell before the refrigerant vapor exits through the shell refrigerant vapor outlet and the second portion is configured such that the at least one second refrigerant vapor distribution outlet opening distributes refrigerant vapor into an interior of the shell before the refrigerant vapor exits through the shell refrigerant vapor outlet; and in that a heat transferring unit is disposed inside of the shell below the refrigerant distributor to receive liquid refrigerant discharged from the second portion of refrigerant distributor supplied to the heat transferring unit.