Specifications include, but are not limited to: Illinois Department of Transportation requires a Vendor to provide all materials, equipment, and labor necessary to provide HVAC maintenance and repairs throughout Rock Island and Henry counties. The successful Vendor will provide general and emergency services for repair, maintenance, and minor alterations to the heating, ventilation, and air conditioning systems, including by not limited to, direct digital controls, distribution systems, chillers, absorption machines, air cooled air conditioner units, heating and cooling roof-top units, water and air condensers, evaporators, direct expansion air conditioning units, air handling units, high and low pressure steam boilers, hot water boilers, centrifugal, circulating, condensate pumps, heat exchangers/converters, exhaust/ventilator fans, pressure reducing valve stations, operations controllers, and temperature control systems.