In 1990, explosive sales and a quest for a state-of-the-art facility that would spotlight the advantages of using geothermal energy led WaterFurnace International, Inc., to build its 115,000-square-foot corporate headquarters and manufacturing plant in Fort Wayne, Indiana. WaterFurnace installed what was at the time the largest geothermal pond loop system in North America to provide the building's heating and cooling.
The system uses a combination of WaterFurnace's own water-to-air and water-to-water geothermal units. Horizontal units condition various zones within the two-story office space and seven large-capacity horizontal units--totaling 70 tons--conditioning the manufacturing area. The total capacity of the system is 153 tons, 134 of which were installed in 1991 and 19 of which were added in 1995. The environmental control for the testing laboratory consists of over four dozen WaterFurnace units. The lab support equipment--totaling 168 tons--uses the pond loop as a tempering medium when lab requirements fluctuate outside of specified limits.