Abstract: An improved geothermal heat exchange unit, which can be placed in ground and/or water, has a rigid hollow core about which is formed a helical winding of thermally conductive tube. The return section of the tube extends vertically along a central axis of the core, separated from the inner wall of the core by thermal insulating material. The heat exchange unit is optionally encased in a solid thermally conductive casing and may have a small diameter oil return tube from the lowermost portion of the unit to the suction intake port of a gas compressor. An optional high pressure water hose is attached for installation assistance in wet sand or wet soils.

Abstract: A geothermal direct expansion heat pump system wherein subterranean heat exchange tubes have an internal diameter to length ratio of between 1/4000 and 1/6000, with 5 tubes per ton of BTU capacity; where the interior air heat exchange tubes have 50% of the interior volume of the subterranean tubes; where the thermal expansion valve is sized to match the interior air handler capacity; where the receiver holds 75% to 95% of the total refrigerant volume; where a pump down sequence is employed on system shut down; where an oil trap is installed at the vapor line existing the subterranean heat exchange tubes; and where 4 refrigerant cut-off/isolation valves are installed for service convenience.