To manufacture heat source equipment easily and efficiently.

For the construction of the heat source equipment where a buried external heat medium pipe 3 connects to a heat source unit 2 and the external heat medium pipe 3 conducts a heat medium L1 to a heat source side heat exchanger 7 or an output side heat exchanger 8 of a heat pump H in the heat source unit 2, the external heat medium pipe 3 is arranged with pipe ends 3a and 3b thereof projected in a predetermined foundation installation position, a precast foundation 1 provided with a hole-shaped or notch-shaped pipe passing portion 14 through which the pipe ends 3a and 3b of the external heat medium pipe 3 are passed for exposure above the foundation is installed in the predetermined foundation installation position with the pipe ends 3a and 3b of the external heat medium pipe 3 passed through the pipe passing portion 14, the heat source unit 2 is installed on the foundation 1, and the pipe ends 3a and 3b of the external heat medium pipe 3 passed through the pipe passing portion 14 are connected to the heat source unit 2.