About 601


We are the union HVAC and refrigeration techs, the pipe welders, and fitters - installing comfort heating and cooling systems, grocery store refrigeration, gas line pumps, food & beverage piping, pharmaceutical and chemical systems, compressed air and gases, hydraulic, and fuel oil systems.  We install and maintain the pipelines that deliver oil to refineries and gasoline from them as well as natural gas to your homes.  The high pressure steam systems we install at power plants help produce the electricity that powers home and businesses.  We install and service the temperature controls and instrumentation systems that allow all of these systems to function safely and efficiently year after year.

Our members work in homes, hospitals, schools, offices and manufacturing plants.  You’ll find us at Miller Brewery and Harley Davidson, to the University of Wisconsin, and the State Capital.  We’re 2400 members strong performing our work throughout 14 counties in Southeastern Wisconsin.

We encourage you to use this website to learn more about what we do, how we work and how we train.