Geothermal.contractors

Whetstone Valley Electric Cooperative, based in Milbank, South Dakota, operates a full-service geothermal and HVAC installation division (Whetstone Geothermal) serving northeast South Dakota. The cooperative's heating and cooling team installs WaterFurnace ground-source geothermal heat pump systems with its own crew, and describes itself as a complete comfort-system provider. Services extend beyond geothermal to conventional air conditioning, heating, and water heater installation, plus maintenance and repair of most major HVAC brands. With its own installation crew and a manufacturer-backed WaterFurnace dealership, Whetstone is an active geothermal installer, not merely a financing or rebate program. Verified active operator per https://whetstonegeothermal.com/ + https://www.waterfurnace.com/residential/dealer-locator/ (SD bundle audit 2026-06-02)