Process Heating and Controls Engineers specializing in gas-fired industrial equipment. Marshall W. Nelson & Associates has production facilities for gas and air valve-train assembly and UL Electrical Panel Fabrication. We are a stocking distributor for several lines of gas related equipment including: Eclipse burners, Sensus regulators and meters, Karl Dungs valves, Antunes controls, Siemens controls, GE Dresser Meters to name a few. Marshall W. Nelson & Associates provides combustion engineering services to the metals industry, dairy and food processing industries, OEM's of makeup air systems, packaging industry and many others. Our service group works throughout the upper Midwest in the Dakotas, Minnesota, Wisconsin, Illinois, Michigan and surrounding states. Our OEM controls solutions are found in system installed all over the world including Australia, Europe, Asia, North and South America and Africa.