A subsurface well completion system including a subsurface heat exchanger section that includes an outer shell and an inner shell having an upper threaded portion, an open inside diameter, one or more inlet boxes and one or more outlet boxes. An upper annular ring extends between the inner shell and the outer shell and has one or more openings. A lower annular ring extends between the inner shell and the outer shell. The lower annular ring is spaced apart from the upper annular ring and has one or more openings. One or more tubes are sealably connected at a first end and a second end to the one or more openings in the upper annular ring and the one or more openings in the lower annular ring, respectively, and extend between the upper and lower annular rings in an annular space between the inner shell and the outer shell.