Vertical Closed Loop or Geothermal Wells This configuration is used mainly when land area is limited or the owner wants a smaller footprint. A drilling rig is used to bore holes at a depth of 100 to 500' deep. A U-shaped coil of high-density pipe is inserted into the borehole. The holes are then back filled with grout. The wells are piped together 5' below ground and ran into the building.
Horizontal Closed Loop or Slinky Used when adequate land area is available. Loop installers use excavation equipment such as a chain, trenchers, backhoes and track hoes to dig trenches approximately 4-6 feet. Trench length range from 100-300 ft/ton depending on the loop design and application.
Open System or Pump and Dump This system can be installed if an abundant supply of high quality well water is available. A typical home will require 4 to 8 gallons of water per minute. A proper discharge area such as another well, river, drainage ditch, stream, pond or lake must be present. Check for local restrictions before selecting a specific discharge method. The heat exchange comes directly from the ground water. Water quality is a major concern.
Pond Loop A pond loop is an option if a large body of water is available within approximately 200 feet of the home. A ½ acre, 10 to 12 foot deep body of water is usually adequate to support the average home. The system uses coils of pipe typically 300 to 500 feet in length. The coils are placed in and anchored at the bottom of the body of water.