There are four main ways that the earth loop for a geothermal system can be installed. The method you choose depends mainly on the size and features of your property. A dealer will be able to help you evaluate your site and suggest the most appropriate loop type for your situation:
Horizontal Straight Loops consist of lengths of pipe installed into trenches under the lawn that are dug using a backhoe or excavator, approximately five feet underground and below the frost line. This is the most common installation type and is very economical as long as there is adequate land area available to dig the trenches.
Horizontal Coiled Loops are similar to the more common horizontal straight loops, except rather than burying straight runs of pipe, the pipe is spread out in flattened, overlapping coils. This type of loop, also known as a Slinky loop, allows for adequate pipe surface area in shorter trenches, allowing it to fit in some areas where horizontal straight loops would be impractical.
Vertical Loops run deep into the ground and are ideal for properties lacking the larger areas of lawn needed for a horizontal loop. They cost more to install than horizontal loop systems, but they have the advantage that they can be installed on small lots where not enough open land exists to install a horizontal loop.
Pond Loops take advantage of an existing body of water located on the property to extract energy with a minimum of excavation work required. The coiled loops are floated into the pond, then filled with liquid and sunk to the bottom. Because there is much less digging required, the pond loop option is often the lowest-cost method for sites that already contain a suitable body of water.