Dave Hague, 28th Civil Engineer Squadron Heating, Ventilation, Air Conditioning and Refrigeration technician, services an electrical wire conduit pipe at Ellsworth Air Force Base, S.D., Sept. 4, 2014. The 28th CES HVAC/R shop has been focused on installing and repairing boilers in preparation for the winter season. (U.S. Air Force photo by Senior Airman Hailey R. Staker/Released)