Union City Municipal Building HVAC Replacement

Project includes removal of existing Variable Air Volume (VAV) boxes and central station air handling units and associated thermostats and controls on floors two, three, and four, removal of existing rooftop makeup air unit and associated controls, and removal of four (4) gas-fired boilers and associated controls. Three (3) Variable Refrigerant Flow (VRF) systems will be provided for the building, one system serving each floor on floors two, three, and four. Three (3) outdoor heat pump towers will be located on the roof. A branch controller box will be provided on each floor. Each of the zones of the building will be provided with ducted indoor fan-coil units mounted above the ceiling. Supply air ductwork will extend from these ceiling concealed indoor units and connect to the existing supply air ducts. Return air ducts will be open-ended and utilize the space above the ceiling as a return air plenum. Condensate piping shall extend from the primary drains at each of the new indoor units and terminate with an indirect waste at a floor drain within a mechanical or utility closet. Two (2) new modular, condensing, gas-fired boilers shall be provided in place of the four boilers that were removed. Two new hot water pumps will be provided to replace two existing pumps. An electronic, direct digital control (DDC) system shall be provided to support operation monitoring, error/alarm notification, set point adjustments and overrides, scheduling, occupancy, error email distribution, etc. for all new HVAC equipment. Control system shall include head end unit with graphics of all components, parameters, and also shall offer remote access via web browser. All work on this contract must be completed within one hundred eighty (180 days per SP-16) calendar days from issuance of a Notice to Proceed. Only mechanical contractors with a minimum of five (5) previous Variable Refrigerant Flow (VRF) projects shall be considered for this project. Contractors shall include documentation of this experience as part of the bid submission. Only mechanical contractors with a minimum of five (5) previous projects installing systems with at least 50-tons total cooling capacity shall be considered for this project. Contractors shall include documentation of this experience as part of the bid submission. Only contractors with a minimum of five (5) previous projects consisting of occupied office renovations shall be considered for this project.

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Heating, Ventilating, and Air Conditioning (HVAC), Instrumentation and Control for HVAC, HVAC Air Distribution, Central HVAC Equipment.