Breadcrumb Home Heating, Ventilation, Air Conditioning and Refrigeration HV123 HV123: Mechanical Controls Download as PDF Subject Area Heating, Ventilation, Air Conditioning and Refrigeration Quarter Credits 6 Clock Hours 120 Lecture Hours 60 Lab Hours 60 Theory and relevant lab exercises reviewing hydronic and forced air systems including component parts, temperature, and ambient controls. Prerequisites HV 132 & HV 151