Slinky coil loops are one of the most common in geothermal ground loop design. The geothermal ground loop design is a key part of the geothermal cooling and heating system and is designed by our in-house Geomaster Engineers. The overlapping coils, made of polyethylene pipe, are used to increase the heat exchange per metre of trench length, but require more coils per kW of capacity. A two-pipe system may require 60 to 100 metres of trench per ton of nominal heat exchange capacity. The trench length decreases as the number of pipes in the trench increases or as Slinky coil overlapping increases. This same Slinky coil system can be used in a lake or pond application.
The concept of the slinky geothermal ground loop design is easy to understand but applying the technology is best left to those with specialist skills and experience. Careful design is necessary to ensure that there is sufficient capacity available for the geothermal heat pump to operate properly. Design consideration is crucial when spacing the pipes in a loop and is important as this affects how much the heating or cooling effect of one pipe influences the heat source or heat sink available to adjacent pipes.