Altoona Looks to Us for Its Geothermal Needs We’re Sherman Co. LLC, the recommended "go-to" team for Altoona, Iowa's geothermal heating and cooling. Altoona homeowners look to us for ... the finest WaterFurnace geothermal heating and cooling systems highend installation and service from highly skilled, highly trained professionals professional advice on how to maximize the potential of their geothermal installations With the economy like it is, there's never been a opportune time to put a WaterFurnace geothermal system to use for you. And we're the professionals to do it in Altoona, Iowa. Contact Sherman Co. LLC today. Want to see just how big "going geothermal" could save you on your energy bills? Take a moment or two with our simple Geothermal Savings Calculator.