Mounting structure and method for heat accumulation tank

A mounting structure for a heat accumulation tank is provided which is capable of reliably holding the heat accumulation tank 1, achieving even surface pressure, and eliminating the possibility of a slow leak. The mounting structure includes an elastic member 39 that wraps around a tank main body 10; and a heat accumulation tank 1 mounting member 30 which wraps around an outer peripheral surface of the elastic member and holds the tank main body 10 by being tightened in the circumferential direction, and which attaches to a receiving member. The elastic member 39 is a molded part. The length of the elastic member 39 is shorter than the length of the circumference of the outer peripheral surface of the tank main body. A mounting structure for a heat accumulation tank is provided which is capable of reliably holding the heat accumulation tank 1, achieving even surface pressure, and eliminating the possibility of a slow leak. The mounting structure includes an elastic member 39 that wraps around a tank main body 10; and a heat accumulation tank 1 mounting member 30 which wraps around an outer peripheral surface of the elastic member and holds the tank main body 10 by being tightened in the circumferential direction, and which attaches to a receiving member. The elastic member 39 is a molded part. The length of the elastic member 39 is shorter than the length of the circumference of the outer peripheral surface of the tank main body.