Mammoth has a 75-year history of building innovative, quality products and satisfying customers throughout the world. Originated in 1935 as the Brown Sheet Iron and Steel Company in St. Louis Park, Minnesota, the company manufactured industrial gravity-flow and forced-air furnaces for both commercial and residential applications.

From this modest beginning, the company experienced explosive growth during World War II, when Brown became a major supplier of large industrial furnaces. Seeing the increasing market potential in the commercial and industrial sector, a small group of investors bought the company in 1953 and chose to focus on those lines. As the largest supplier of the largest product on the market, the company was renamed the Mammoth Furnace Company.

In 1965, the growing company became the Mammoth Division of Lear Siegler, Inc. It acquired a heat-pump manufacturing company in Holland, Michigan, and a coil manufacturing plant in New Germany, Minnesota. The St. Louis Park facility was expanded to keep pace with growing manufacturing requirements. After 29 years in the western suburbs of Minneapolis, in 1995, Mammoth moved to a new facility in Chaska, Minnesota.

In addition to its namesake brand, Mammoth also owned the WEBCO brand. Founded in 1977 by Mr. William Eugene Bennet (retired), in Springfield, MO, WEBCO was licensed by The Wing Company to sell and fabricate Wing's rooftop energy recovery packages. Today, the WEBCO brand is recognized for custom air conditioning equipment that provides innovative, cost-effective solutions for some of today's most challenging air conditioning and air quality applications in critical environments such as automotive manufacturing, pharmaceuticals, bio-tech, food processing, and air terminals.

Today, Mammoth is a brand of Nortek Air Solutions, LLC, the largest manufacturer and marketer of custom HVAC systems in North America. 

While its name and location have changed, the Mammoth brand continues to stand for leadership in quality, custom-built HVAC equipment.