NAVFAC Building 1475 Replace AHU-2 BU & ACCU-2 BU, NNSY, Portsmouth, VA

The project is to demolishing one (1) rooftop air handling unit (AHU-2 Back-up) (25,000 CFM); one (1) remote mounted 80 Ton air-cooled condensing unit (ACU-2 Back-up); 100% of the refrigerant piping and associated appurtenances from the AHU DX cooling coil and the air-cooled condensing unit; supply air, return air, and relief air ductwork from AHU connections to points indicated; 2" low pressure steam (LPS) and 1-1/4" low pressure condensate (LPC) piping from AHU steam heating coils to points indicated; 3" LPS and 1-1/4" LPC piping (serving duct mounted steam heating coil) between points indicated; all pneumatic controls, tubing, conduit, wiring and related appurtenances serving AHU and return air fan (RAF-2 Back-up) and mounted to ductwork to be demolished; two (2) pneumatic damper actuators, tubing, and conduit for isolation damper and inlet guide vanes serving RAF-2 Back-up; two (2) pneumatic damper actuators, tubing, and conduit for supply air and relief air isolation dampers serving AHU-2 Back-up; structural steel support framing for AHU-2 Back-up and ductwork to points indicated; strip and clean paint from structural steel support for ACU-2 Back-up; one (1) disconnect, seal tite, and all conductors from ACU-2 Back-up to breaker located in motor control center in second floor electrical room; one (1) disconnect, seal tite, conduit from disconnect to 12" below the roof deck, and all conductors from AHU-2 Backup to breaker located in motor control center in second floor electrical room; and incidental related work. The work includes providing one (1) rooftop air handling unit (AHU-2 Back-up) (25,000 CFM); one (1) remote mounted 80 Ton air-cooled condensing unit (ACCU-2 Back-up); refrigerant piping, fittings, valves, filter driers, and associated appurtenances from the AHU DX cooling coil to the air-cooled condensing unit; supply air, return air, and relief air ductwork from AHU connections to points indicated; LPS and LPC piping from AHU steam heating coils to points indicated; direct digital controls, conduit, wiring and required appurtenances to control AHU-2 Back-up, existing return air fan (RAF-2 Back-up) and ACCU-2 Back-up; two (2) electronic motorized damper actuators, wiring, and conduit to for the existing isolation damper and inlet guide vanes serving RAF-2 Back-up; two (2) electronic motorized damper actuators, wiring, and conduit to the existing supply air and relief air isolation dampers serving AHU-2 Back-up; structural steel support framing for AHU-2 Back-up, ductwork, and piping, as indicated; paint existing structural steel support framing for ACCU-2 Back-up; one (1) disconnect, seal tite, and all conductors from ACCU-2 Back-up to breaker located in motor control center in second floor electrical room; one (1) disconnect, variable frequency drive, seal tite, conduit from disconnect from below the roof deck to the disconnect, and all conductors from AHU-2 Back-up to breaker located in motor control center in second floor electrical room; and incidental related work. The work includes providing Testing, Adjusting, and Balancing (TAB) for AHU-2 Back-up, existing return air fan (RAF-2 Back-up) and associated duct systems. This project meets the definition of either a renovation or demolition under the national emissions standards for hazardous air pollutants (NESHAP), a thorough inspection is required to identify suspect asbestos containing materials to be disturbed prior to any work being performed.

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