First of all, what is a loop system?
It is the vehicle that transfers heat to or from the ground or ground-water.
There are basically four different types of loops: Closed Loop- Vertical, Closed Loop- Horizontal, Closed Loop- Lake or Pond, Open Loop- Well System.
Which is right for you?
Well that depends on several factors including: land terrain, the cost of trenching or drilling, the availability of quality ground water and the availability of land.
Closed Loop- Vertical:
If land area is limited, closed loops can be inserted into vertical bore holes. Holes are drilled to a depth of about 125 to 200 feet. U-shaped loops of pipe are inserted into the holes. The holes are then backfilled with a sealing solution.
Closed Loop- Horizontal:
If adequate land is available, horizontal loops can be installed. using a chain trencher or backhoe, the loop installer digs one or more trenches four to six feet deep. One layer or multiple layers of earth loop pipe can be laid in a trench with soil backfilled between the layers. Trench lengths range from 100 to 300 feet, depending on the loop design and application.
Another technique utilizes special equipment to bore holes horizontally under the surface. This technology creates a small diameter tunnel underground by displacing soil with pressurized water. Through the use of a radio beacon, operators track the location of the drill head and steer it as it progresses under the surface. After about 150 to 220 feet of drilling, the pipe is inserted into the tunnel.
This technique allows the loop to be placed underneath homes, basements, wooded lots or even swimming pools without disrupting grass or landscaping.
Closed Loop- Lake or Pond:
Because water transfers heat better than soil, closed loops can be coiled and placed on the bottom of a pond or lake where it transfers heat to or from the water. A 1/2 acre, 8 foot deep pond is usually sufficient. Pond or lake loops often require less excavation than vertical and horizontal loops; therefore, they are often less expensive to install.
Open Loop- Well System:
If an abundant supply of quality well water is available, an open loop system can be installed. The well must have enough capacity to provide adequate water flow for both domestic use and the GeoExchange unit throughout the year. A proper discharge site, such as a ditch, field tile, stream, or pond, must be available. Be sure to check all local codes before selecting a discharge method. Since closed loop trenching is unnecessary, this installation usually costs less to install and delivers the same high efficiency.
