LOOP TO LOOP with GEOEXCHANGE
There are two primary types of geothermal geoexchange systems: open-loop ageoexchange nd closed-loop .geoexchange Open loop geoexchange systems operate from well water and require space for water discharge. Closed-loop  geoexchange methods, however, circulate water and non-toxic antifreeze through a series of buried HDPE polyethylene pipes. The closed loop geoexchange varieties include geoexchange pond loops, horizontal trgeoexchange ench loops and vertical geoexchange loops.
GEOTHERMAL GEOEXCHANGE OPEN-LOOP SYSTEMS
The open-loop geoexchange variety requires a source of feed water, such as a well. They are less expensive to install, but may cost more to maintain if your water supply is unreliable. At a typical open-loop geoexchange system ranges in cost from $20,00 for the best 2.5-ton system to $40,000 for a two-speed, 6-ton unit. That includes interior plumbing materials, complete installation and a ten-year warranty.
While the majority of rural wells can be used with a geothermal geoexchange system, there are exceptions. One problem can be the presence of iron bacteria in your water. Though not fit for human consumption, they will cause a troublesome buildup of iron deposits inside plumbing. If your water source contains iron bacteria, you might want to consider a closed-loop geoexchange system.
If you're considering an geothermal geoexchange open-loop system, make sure your water supply or well can meet the following guidelines. (Note: More specific questions regarding the chemical content of nonpotable water and its suitability for use are best directed to an equipment manufacturer.)
• Untreated water must be potable (no brackish or rotten egg odors).
• The water table should be within 100 feet of the surface.
• The volume of available water should be equal to twice the peak household use.
• Wells drilled into shallow bedrock and specifically into karst (cavernous limestone) formations function best if the casing can extend below the pumping water level. (Shallow water is easily contaminated.)
• Wells drilled into sand and gravel formations function best if a well screen is installed. (Well screens dramatically increase the capacity of a well and assure a longer lasting and more reliable water supply.
• Lastly, always avoid the use of galvanized pipe fittings and steel pipe with any water system. Galvanized steel is easily corroded by electrolysis and will fail within a few years.
Closed-loop geoexchange systems are clean, very low-maintenance and usually carry a loop materials warranty of 25 to 100 years.

geoxchange@magnumpm.com.
GEOTHERMAL GEOEXCHANGE CLOSED-LOOP SYSTEMS
The good thing about closed loop geoethermal geoexchange systems is that they can be installed almost anywhere. The loop is filled once with clean water and nontoxic antifreeze, and a small pump recirculates the antifreeze solution between the loop and the exchange system. Geothermal geoexchange closed loop systems remain clean, are very low on maintenance and usually carry a loop materials' warranty of 25 to 55 years. The three types of closed-loops geoexchange ystems are pond, horizontal geoexchange and vertical  geoexchange.
Pond Loops For a six-ton geothermal geoexchange system a pond loop typically requires a pond size of at least half an acre and a minimum depth of eight feet. Smaller ponds may experience thermal fluctuations from the geoexchange system, which can be stressful to aquatic life. In central Ohio, larger ponds typically run temperatures of 70°F at eight feet in the summer, and 38°F in the winter.
A hot water unit and pump . Coring a path into the house. A 2" hole is drilled through the foundation. A 2" PVC sleeve is inserted and watersealed.
Pond geoexchange loops are typically the lowest costing design of closed geoexchange loop heat exchanger. The average cost per geoexchange ton of capacity runs more affordable for materials, antifreeze andgeoexchange labor. A complete installation of geoexchange equipment, a 10-year warranty and a geoexchange loop attached to existing ductwork costs from $18,000 for a 2.5-ton unit to $30,000 for a two-speed, six-ton size unit. To make geoexchange trenching to a pond practical, the geoexchange pond should be at a lower elevation than the home and no more than 100 meters away. Soil conditions should allow for geoexchange trenching without encountering bedrock or difficult terrain.
Pond lgeoexchange oops are typically constructed from 300-foot rolls of 0.75-inch polyethylene pipe that carry SDR11 rating. The rolls are prepared with spacers between each layer of pipe - once all spacers are in place and the rolls are banded tightly, the spacers are attached to a manifold constructed from one-inch SCH 40 polyethylene pipe. This geoexchange manifold uses a connection method called "reverse return", in which the first circuit on the supply line is connected as the last circuit on the return side. This requires more geoexchange manifold pipe but assures that each geoexchange parallel circuit of pipe on the geoexchange manifold receives equal flow. geoxchange@magnumpm.com.
Horizontal Geoexchange Loops Horizontal geoexchange loops typically require two or more acres of unrestricted open area for igeoexchange nstallation and the cost of a horizontal geoexchange loop will vary according to the geoexchange loop design and the local site conditions. Typical geoexchange costs range from $600 to a little more than $1,000 per ton of loop capacity. Complete geoexchange systems with ten-year warranties, installed with loops and attached to existing duct work range in price from $11,700 for a 2.5-ton system to $18,500 for a six-ton, two-speed system.
The simplest horizontal loop is a single pipe loop constructed from 1.25-inch polyethylene pipe. Single pipe geoexchange loops of up to 1,600 feet may be constructed and placed in the bottom of a simple out and back geoexchange trench dug to three to five feet. Typically, the deeper the geoexchange pipe is placed, the more stable the soil temperature will be. The length of geoexchange pipe required for horizontal geoexchange loops ranges from just under 750 feet per ton for light dry soil to as little as 350 feet per geoexchange ton for heavy, saturated soil.
More involved geoexchange horizontal loops may assume any number of configurations depending on lot and soil conditions. In addition to the single-pipe geoexchange trench, there are two-, three-, four- and six-pipe trenches. As the number of geoexchange pipes in a trench increases, of course, so does the width, which allows geoexchange contractors to lay extended-pipe loops in what is known as "slinky" loops. geoxchange@magnumpm.com.

Geoexchange Slinky Loop

A typical geoexchange slinky-loop field may consist of four or five parallel trenches separated by ten to 15 feet and laid with 600 feet of coil. with an experienced crew of four - track-hoe operator, safety-man and two loop installers - the average work time to install a geoexchange slinky loop is about an hour and 20 minutes per ton of coil. After all costs are accounted for, slinky loop installation averages $800 per geoexchange ton.geoxchange@magnumpm.com.

Geoexchange Vertical Loops
For small lots and locations with little acreage, geoexchange vertical loops are an economical alternative. They require the use of a geoexchange drilling rig to bore a four-inch diameter hole for the geoexchange heat exchanger piping. Depending on soil and rock conditions, the depth of a geoexchange vertical loop bore can range 130 to 245 feet per ton of geoexchange equipment capacity. Drilling geoexchange costs, with geoexchange manifold connections and ageoexchange ntifreeze fill, average $1,500 to $1,800 per ton. Local geoexchange drilling costs vary, so vertical geoexchange loops can range from $12,600 for a 2.5-ton geoexchange system to as much as $21,870 for a six-ton, two-speed system with a ten-year equipment warranty. When possible, vertical geoexchange wells are separated by 15 feet to avoid thermal interference between wells. The closed-loop heat exchanger is constructed from two parallel lengths of 0.75-inch geoexchange polyethylene pipe, and a geoexchange "U" bend is welded to the bottom end to connect the geoexchange supply and geoexchange return side of the exchanger. Once the exchanger is assembled, it is pressure-tested and a ten-foot section of re-bar is taped to it to keep the lead section straight. Next, a geoexchange grout line is loosely attached and the exchanger is filled with water to prevent it from floating back out of the well if the well begins to fill with water. Once inserted into the geoexchange well, the bore is grouted up with a geoexchange bentonite clay slurry and the grout pipe is removed for reuse on the next well. The geoexchange bentonite grout serves two functions: to seal the geoexchange well and prevent contamination from surface sources, and to provide a medium for heat transfer between the exchanger tubing and the side wall of the well bore.