A fuel cell apparatus , comprising: a fuel cell module ; a heat exchanger which carries out heat exchange between exhaust gas from the fuel cell module and a medium; a circulation line connected to the heat exchanger , the circulation line allowing the medium to circulate the heat exchanger ; a heat dissipator located in the circulation line , the heat dissipator cooling the medium flowing through the heat exchanger ; and an exterior case which houses the fuel cell module , the heat exchanger , the heat dissipator , and at least part of the circulation line , the heat dissipator provided with two openings, the heat dissipator comprising at least a duct which defines an air flow channel between the two openings ; a fan located closer to one opening of the two openings than the other opening in the air flow channel , the fan producing flowing air; and a radiator located closer to the other opening of the two openings than the one opening in the air flow channel , the radiator carrying out heat exchange between the medium and air flowing through an interior of the air flow channel , the exterior case provided with two ventilation holes to which the two openings are connected directly or via an air passageway, respectively, the duct comprising a plurality of separable parts; wherein the plurality of separable parts of the duct include at least a first duct (59A1) located close to the one opening ; and wherein the plurality of separable parts of the duct include, in addition to the first duct (59A1), an upper duct and a lower duct which are vertically separable from each other. a fuel cell module ; a heat exchanger which carries out heat exchange between exhaust gas from the fuel cell module and a medium; a circulation line connected to the heat exchanger , the circulation line allowing the medium to circulate the heat exchanger ; a heat dissipator located in the circulation line , the heat dissipator cooling the medium flowing through the heat exchanger ; and an exterior case which houses the fuel cell module , the heat exchanger , the heat dissipator , and at least part of the circulation line , the heat dissipator provided with two openings, the heat dissipator comprising at least a duct which defines an air flow channel between the two openings ; a fan located closer to one opening of the two openings than the other opening in the air flow channel , the fan producing flowing air; and a radiator located closer to the other opening of the two openings than the one opening in the air flow channel , the radiator carrying out heat exchange between the medium and air flowing through an interior of the air flow channel , a duct which defines an air flow channel between the two openings ; a fan located closer to one opening of the two openings than the other opening in the air flow channel , the fan producing flowing air; and a radiator located closer to the other opening of the two openings than the one opening in the air flow channel , the radiator carrying out heat exchange between the medium and air flowing through an interior of the air flow channel , the exterior case provided with two ventilation holes to which the two openings are connected directly or via an air passageway, respectively, the duct comprising a plurality of separable parts; wherein the plurality of separable parts of the duct include at least a first duct (59A1) located close to the one opening ; and wherein the plurality of separable parts of the duct include, in addition to the first duct (59A1), an upper duct and a lower duct which are vertically separable from each other. <EOS>