Mechanical Supply Company Inc started business in 1955 in St. Louis, MO. The company operated two different mid-town locations until 1990. Our first branch store was opened in 1961 in Springfield, IL. We are currently operating from our third Springfield location at 2785 South 11th Street in a large modern building designed for our type of business. Our third location was opened in 1972 at 96 Weldon Parkway, Maryland Heights, MO. This was the first HVAC/R West County location in the St. Louis Metro Area. The store size was doubled in 1987 to stock a broader product offering to an expanding customer base. Our fourth store opened in Fairview Heights, IL in 1989 and was moved to a larger building at our present location 319 Centreville Avenue in Belleville, IL. This store serves a growing Metro East population and features commercial packaged heating and cooling equipment storage.