Pipefitter I - IV As a Pipefitter (Levels I–IV), you'll play a critical role in commercial mechanical service and installation, progressing from entry-level assistance to master-level expertise in wet-side piping systems (hydronic heating, chilled water, steam, boilers, chillers, process piping) for buildings, hospitals, schools, and industrial facilities nationwide. Work on diverse, hands-on projects—from basic support and repairs to leading complex installations, crew oversight, project plann…