What is the term used to describe a plumbing system worker who manages repairs and upkeep?

The term that best describes a plumbing system worker who manages repairs and upkeep is "Maintenance Man." This designation refers to an individual responsible for the general care, repair, and maintenance of plumbing systems within residential, commercial, or industrial settings. They typically handle routine maintenance tasks and address issues as they arise, ensuring that plumbing systems remain functional and efficient.

Other roles such as a Plumbing Supervisor, Plumbing Manager, or Plumbing Technician may involve overseeing teams, managing projects, or conducting specific plumbing tasks. However, these titles may imply a broader scope of responsibilities or a supervisory position rather than focusing solely on repair and upkeep like the term "Maintenance Man" conveys.