Contractor shall provide all necessary materials, supplies, tools, equipment, transportation, licenses, permits, prevailing wages, insurance, bonds, and personnel to provide DSH-Napa with the removal of one (1) existing absorption chiller and replace with one (1) already purchased new electric centrifugal chiller. Provide and install a refrigerant monitoring system, exhaust system and insulated chilled water piping elbows on the roof, as designed in the attached J.C. Chang and Associates(JCCA) drawings, specifications and structural