We're the Geothermal Source in Old Saybrook! Old Saybrook homeowners in the know look to Nero Air Conditioning and Heating for all their geothermal heating and cooling needs. They place their confidence in us to provide not only the correct installation and service but also the experience to help them get the most from their geothermal systems. Considering a geothermal system of your own? Give our nifty little Geothermal Savings Calculator a whirl. Just fill-in your data and marvel at the results. Then, contact us, the Old Saybrook, Connecticut, geothermal experts at Nero Air Conditioning and Heating.