Thief River Falls, Minnesota, Geothermal Ambient Geothermal is the top WaterFurnace geothermal contractor in Thief River Falls, Minnesota. We'll help you comprehend all the benefits of geothermal heating and cooling. We’ll make sure your WaterFurnace system is correctly installed, too. And when it comes time for service? Nobody in Thief River Falls does it better! Contact Ambient Geothermal today. Like a little up-front look at the savings a WaterFurnace geothermal heating and cooling system can provide? Use our handy Geothermal Savings Calculator.