The Geothermal Name to Trust in Marshall County Forgive the pride, but that would be us: Gast Heating & Cooling Inc.! Marshall County, Indiana, residents have been looking to us to meet their geothermal heating and cooling needs for a number of years, now. We'd like to earn your assurance, as well. If you've been wanting to "go geothermal" but have put it off, you can certainly trust us on this: given today's shifting economy, there's never been a better time to learn more about the savings a geothermal heating and cooling system can offer. Want facts? Do a little simple math with our Geothermal Savings Calculator. Then contact Gast Heating & Cooling Inc. for the very best geothermal system installation and service in Marshall County - and beyond! Oh ... and talk about trust: We install geothermal heating and cooling systems by WaterFurnace. That's a brand that resounds in the geothermal industry.