General Heating and Air Conditioning, Inc. Conveniently arranged by category, see descriptions of many of our Commercial clients, along with information about the specific HVAC needs we've addressed in each of their distinctive facilities. Our base operation in Madison, Wisconsin actively pursues business throughout the state of Wisconsin. Additionally, on a selective basis, we have successfully served clients' needs in Iowa, Minnesota, Illinois and Indiana. Learn about the products and services we offer local homeowners, from furnace and air conditioning units to boilers and appealing "home c