Schlatters Plumbing Heating & AC in Defiance Geothermal We would like to welcome you to Schlatters Plumbing Heating & AC's Defiance geothermal resource center. We're honored to be a full-service provider of geothermal products for the Defiance area. Whether you need routine maintenance, equipment repair, or an entire comfort system - Schlatters Plumbing Heating & AC has the education and expertise you need. Let us build you a solution that uses the clean, renewable energy in your backyard to give you savings up to 70% on heating, cooling and hot water. To find out more about our full line of geothermal products for the Defiance area, contact Schlatters Plumbing Heating & AC today.