MRI Air Handling Unit Modification at Veterans Affairs Medical Center

of Work: Provide design build service for the installation of dedicated cooling source to the recently installed air handling unit (AHU) serving the MRI suite in the basement of the OPC building 15 at Veteran s Affairs Medical Center, 800 Poly place Brooklyn, NY 11209 in accordance with the existing AHU manufacturer specifications and VA specifications at http://www.cfm.va.gov/til/specs.asp. Work shall meet all VA design guidelines and

requirements. Specific Requirement: The Contractor will furnish all on-site investigations, engineering, construction drawings, submittals, labor, materials, tools, supervision, equipment, safety, necessary to provide for the construction and functional performance testing of a new supplemental air-cooled chilled water system and hallway chilled water fan coil system for the Magnetic Resonance Imaging (MRI) Suite and its Air Handling Unit. The

scope of work to be performed includes, but is not limited to, the following elements: The contractor will furnish and install a new air-cooled nominal 30-ton capacity electric chiller to supply chilled water to an existing chilled water coil in the existing Air Handler dedicated for the MRI suite in the basement of OPC building 15. The new air-cooled chiller system will utilize an integral skid mounted compressor, evaporator heat exchangers, power panel, control panel and chilled water buffer tank with a remote air-cooled refrigerant condenser located outside and adjacent to the building on grade. Both the interior below grade compressor and heat exchanger skid and the on-grade air cooled condenser skid shall be mounted atop concrete equipment pads. The poured in place of concrete equipment pads will be designed and constructed by the Contractor at locations within the below grade MRI suite s Mechanical Room and outside the building on grade adjacent to the building. Approximate locations for these two equipment pads are provided on the attached drawings. The existing Air Handling Unit chilled water coil is provided with chilled water by the general building chilled water system. This general building chilled water system is turned off during the heating season, but the MRI suite still requires mechanical cooling to maintain the necessary operating environments for the MRI machine and the patient and staff spaces due to the heat generated by the MRI equipment. The Contractor will design the new chiller equipment and piping to provide shoulder and winter month period supply of chilled water to the MRI AHU. The switch over from summer operation to cool weather operation for the chilled water system, and back again, shall be capable of performing remotely through connection and programming with the existing Honeywell Building automation system (BAS). The contractor shall design, furnish, install, program and commission a complete and fully operational Direct Digital Control system interface between the new air-cooled chiller and the piping connection actuated control valves to the existing Honeywell Building Automation System (BAS). The contractor will provide and install two new electrically actuated three-way flanged three (3) inch full port ball valves in the existing chilled water supply and return piping to the MRI AHU chilled water coil. These valves will be installed in the existing 3-inch diameter pipe sections of the general building chilled water lines supplying chilled water to the MRI Air Handling Unit (AHU) chilled water coil. The contractor will furnish and install two new manual operated full port three (3) inch ball valves upstream of the new three-way automated ball valves to provide isolation of the new three-way valves, the AHU and new air-cooled chiller from the general building chilled water piping system. The contractor will additionally provide two new manually operated full port three-inch ball valves downstream of the piping connections at the three-way valves from and to the new air-cooled chiller. The manual ball valves shall be provided with factory lockable handles for proper LOTO isolation operation. The contractor will furnish and install six (6) new nominal 18000 btu/h chilled water surface mounted fan coil units in the hallway that runs alongside the MRI suite and associated Mechanical room. The contractor will provide all necessary chilled water supply and return piping for the new fan coil units. The new chilled water supply and return lines shall be connected to the existing three inch (3 inch) chilled water lines between the new three-way valves and the MRI AHU chiller coil. This connection shall have manual operated isolation ball valves installed at the general piping connections. Drain valves will be installed at the isolation ball valves, and vent valves installed at the piping high points to facilitate gravity draining the fan coil supply and return lines. The new fan coil supply line will be provided with a flanged connection in-line circulating pump to provide necessary flows to achieve full fan coil system cooling capacity. The circulating pump will be provided with a wye strainer and isolation valves on each side of the pump to allow ease of replacement. The contractor will provide a piping and pump design which will supply the fan coils with chilled water flows as required for full design cooling capacity taking into account fan coil and piping system pressure drops and be capable of accommodating the full range of fan coil cooling operations, from no flow to full flow within the pumps recommended range of operations. The contractor will provide all necessary onsite investigations, site photographs and measurements for a complete, coordinated and fully functional mechanical system and construction design based on the as-built conditions of existing piping, Air Handling equipment, ductwork, lighting, electrical power distribution equipment and raceway, space availability, wall, floor and ceiling construction and constraints of the floor, walls and ceiling areas and outdoor area designated for the remote air condenser pad and equipment. The contractor will not rely on the availability or accuracy of existing construction or shop drawings in the proposal development, or on developing the new work design drawings. There are two optional locations for the outdoor ground mounted air-cooled condenser equipment shown on the drawings. The contractor shall evaluate both locations for suitability relative to optimized equipment protection, pipe routing, power availability and ground conditions. The VA COR will provide final determination of which location option is utilized. The MRI Air Handler is a DAIKIN Model # CAH012GDGM. The

Scope of work includes providing all necessary investigations, design development calculations, construction and coordination drawings, design submittals, submittals required by specifications, equipment, including a liquid chiller system with a remote air cooled condenser, chilled water buffer tank, expansion tank, variable speed drive pumps to provide chilled water flow from the surge tank to the AHU coil, primary chiller pumps to pump water from the surge tank thru the evaporator heat exchanger back to the surge tank, side stream chemical treatment assembly, piping, fittings, vibration isolation connections between the chiller and the piping connections, refrigeration piping and accessories, chilled water piping, fan coil equipment, fan coil condensate collection and pumping system including piping to a sanitary drain pipe connection point (no condensate water can drain across the floor to a drain), manual and automated control devices, analog and DDC system sensors (temperature of air and liquids), flow sensors, condensate pump receiver high water alarms, automated valve actuators with position sensors and closure switches, pipe insulation, electrical power, BAS power and control wiring, BAS programming and testing, and all necessary work for a complete and fully functional system. The Basis of design chiller with remotely located air cooled condenser is a Thermal Care 30-ton TSE series Central Chiller with dual circuit, low GWP R-4554B refrigerant, BACnet communications, 5- year compressor parts warranty, CONNEX 4.0 for system wide control, Hot Gas By-pass, Model TSER30D, with a dual circuit remote air-cooled condenser, Model KCL047. The chiller will be provided with optional dual standby pumps. The equipment general specifications can be found at the following Thermal Care website: https://www.thermalcare.com/tse-with-tank/ Proposed alternative As Equal equipment may be submitted from an alternative single manufacturer, with as equal or greater capacities, energy performance, build features, corrosion protection and options for VA review and consideration. The contractor will furnish all necessary engineering, equipment, Digital control modifications and sequence of operation compatible with the existing Honeywell BMS system for the new chiller equipment, fan coils fans and modulating valves, actuated chilled water valves, valve position indication, condensate receiver pump (high water alarm) and associated sensors and equipment to provide a complete and fully functional system. The contractor furnishes and installs six new 600 cfm, 18,000 Btu output, two pipe chilled water ceiling mounted fan coils (approx. 45 degrees in 55-degree fluid out), to serve existing MRI building patient access hallways (350 ft x 8 feet wide). Work scope includes necessary distribution piping, control valves, shutoff valves, condensate drain piping, pipe through wall penetrations and fire caulking, condensate pump receivers with automatic control, pipe insulation, connection to the new chiller piping and existing general building chilled water piping, circulation pumps and electrical power wiring for fans, pumps and controls to achieve full fan coil cooling functional performance. New wiring, cooling piping and condensate piping will be designed and installed not to be exposed within patient hallways, offices, diagnostic spaces or waiting room areas. Fan coil condensate drain pans shall be insulated stainless steel construction. Fans shall be multi-speed, controls shall be BACnet communication compatible, control valve shall be provided with a modulating electric actuator. All piping shall be insulated, have easily accessible isolation valves and union connections for maintenance and replacement. All Electrical work necessary for the new chiller, the new chiller air-cooled condenser, the Fan Coil Units, condensate pumps and chilled water pumps, etc. utilizing existing Electrical panel PP-BE-2 480Y/277V 3PH 4W located in Mechanical room. The contractor will comply with the facility lock-out tag out

requirements, including requesting power and chilled water outages 14 calendar days in advance for VA COR review and concurrence in writing. Power and chilled water outages will need to be performed during off-shift periods, including evenings and weekends, to mitigate impacts to medical center operations. Power, grounding and control wiring to the new air-cooled condenser equipment shall be run from the building to the new exterior equipment pad underground and come up thru the new concrete equipment pad utilizing rigid steel conduit wrapped in anti-corrosion tape per VA underground electrical specification 26 05 41

requirements. All wiring in the building, both electrical power and controls, shall be run in steel rigid conduit, EMT conduit and liquid tight flexible metal conduit, where allowed, and all raceways will be properly supported by NEC code, VA Specifications and best industry practices. All exterior conduits shall be rigid metal conduit and liquid tight flexible conduit at equipment connections. Exterior power disconnect boxes shall be Nema 4X rated. All Unistrut metal channel strut, or equivalent, fittings and rods or anchors used shall be hot dip galvanized if located exterior to the building and chromate zinc plated if used within the building. The contractor will design, furnish and install a new concrete equipment pad to support the new skid-mounted air-cooled chiller near the MRI Air Handling Unit in the building below grade mechanical room. The new concrete equipment pad will be constructed onto the existing floor. The floor area upon which the new concrete pad will be power tool scarified to substantially roughen the existing floor concrete to enhance bounding between the new concrete and the existing concrete and with the addition of an exterior grade latex bounding compound. A minimum of six half inch diameter steel dowels shall be drilled into the existing concrete floor 3 inches and project 4 inches above the concrete floor. The new equipment pad shall be minimally five and one halve inches above the existing floor with width and length dimensions to project at least 6 inches beyond the new chiller skid mounted equipment on all sides. The horizontal and vertical edges of the new slab shall be provided with a 1-1/2 inch formed chamber. The new equipment skid shall be provided with steel plate reinforced neoprene vibration isolators at all anchor bolt locations. Minimum four 5/8-inch diameter anchor bolts are required to secure the new equipment skid to the concrete pad. After a minimum of 30 days cure time, the new equipment concrete pad shall be primed and painted yellow. Concrete coating systems and final color to be submitted to the VA COR for approval. The contract will design, furnish and install a new concrete pad for the chiller air cooled condenser exterior to the building. Two potential locations are shown on provided drawings. The contractor will evaluate each location and make recommendations to the VA COR as to which location provides the most protection of the equipment relative to potential for vehicle traffic impacts, least impact from snow drifting and maintenance access. The VA COR shall choose the location which best meets these criteria. The new concrete pad must extend a minimum of 12 inches beyond the greatest width and length dimension on each side of the new air-cooled condenser to ensure the new equipment is well set back on the pad to protect from equipment contact. The new concrete pad shall be designed with steel reinforcement rod in both directions top and bottom of the pad to prevent shrinkage cracking. The pad shall extend down in the ground at the perimeter to a minimum of 32 inches below grade and extend a minimum of 12 inches above grade, with the top surface provided with a positive drainage slope equidistant from the long center of the pad. All corners, horizontal and vertical, shall be provided with a formed 1-1/2-inch x 1-1/2-inch chamfer. The new concrete pad shall utilize air entrained concrete for freeze thaw protection. The new pad shall be formed and poured atop 12 inches of vibratory compacted graded gravel. The contractor shall provide a minimum 6-inchthick layer of 1 inch round washed river stones around the new pad to complete the installation. The new round stone landscaping shall extend minimally 12 inches beyond the new wire mesh fencing and be graded level with the existing grass lawn. There is to be no grass within the fenced equipment area. The contractor will include all the electrical power and controls installations for the new equipment. Functional performance test procedures, including verification of proper wiring, wiring continuity checks, proper flow verification, control actuation, alarming and new BMS system Graphics integration and control, shall be submitted to the VA COR 30 days prior to system pre-functional testing for VA review and approval. The contractor will integrate and connect the new units into the new Honeywell BMS including all necessary programming and new graphics for complete and fully functional installation. The contractor shall furnish and install all individual n/p thermostats. The fan coil units are to be ceiling mounted with a depth of approximately 14" and approximate length 53 . The fan coil units shall be provided with stainless steel externally insulated condensate drip pans, modulating control valves, 0.018-inch minimum thickness copper coils, MERV 8 pleated filters, ECM motors, Side Access Electrical enclosure, digital fan speed controller, Isolation valves, union and P/T ports connections, adjustable flow control valves for balancing. 18-gauge galvanized steel cabinet construction. The contractor will restore work areas to normal pre-construction conditions, including celling restoration, walls and floors etc. The contractor will clean up as needed daily while they are on site. The contractor will provide their own dumpster to throughout the debris. The contractor will furnish and install a 72-inch-high heavy gauge galvanized wire mesh fence with a lockable hinged swing style access door around the new air-cooled unit. Fencing shall be provided via VA specification 32 31 13. The fence shall be located not less than four (4) feet beyond the sides of the new equipment pad. The ground between the new equipment pad and 12 inches beyond the new wire mesh fence shall be a minimum 6-inch-thick layer of 1 inch round washed river stone. The Contractor will review and incorporate in the project design the VA Design Manuals, Design Procedures, Design Checklists, Standard Construction Specifications and Graphic standards provided publicly online at the VA Technical Information Library (VA-TIL). These documents are listed individually in Attachment A of this specification. VA Design and Construction standards take precedence in design document development and construction