EARTH ENERGY SYSTEMS, INC. - 51 Foley Street, Santa Rosa, CA 95401 - CA Lic. # 739840
Ph (707)523-4363  -  Fax (707)523-4360
info@earthenergysystems.com

Vertical loops are drilled on average between 200 and 400 feet deep.  The average 5,000 square foot home requires 8 bore holes about 200 feet deep.  Into each bore hole is installed a polyethylene pipe which extends from top of the hole down to the bottom and back in a closed loop.  

 
Courtesy of Geothermal Heat Pump Consortium, Inc.

The loops from each bore hole are connected to each other 4 feet below grade with heat fusion.  The bore holes are about 4 3/4" in diameter and are sealed with bentonite around the pipe from the bottom of the bore hole to the top.  The provides good thermal transfer between the pipes and the earth and seals the bore hole.

  Drilling rig installing pipe in a vertical hole (click on image to enlarge)

It usually takes about a week to install a ground loop for a residential home.  Commercial installations usually require many more loops and of course a longer time to complete.

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