Revised 4-17-21 SOW - REPLACE NFS AND PHARMACY REFRIGERATORS AND FREEZERS.docx

Statement of Work Replace NFS & Pharmacy Refrigerators and Freezers Project #667-21-101

I. OVERVIEW

Overton brooks VA Medical Center has a requirement to replace seven walk-in refrigeration units for Nutrition and Food Service and Pharmacy Department in Building 1, Basement Floor. Contractor will replace the existing refrigeration boxes and mechanical components, repair existing plumbing leaks above the boxes, expand the refrigeration mechanical equipment room by demolishing an adjacent closet space, install adequate ventilation inside the mechanical room, increase accessibility to related spaces, provide a temporary covered walkway and ramps for the temporary refrigeration units onsite, and all work defined within this scope of work, projection drawings, and specifications. All work shall be performed as specified herein and shall be in accordance with all applicable codes indicated in the Department of Veterans Affairs (VA) Design Manuals and any other applicable codes. The Contractor shall provide all necessary labor, materials, tools, equipment, licenses, permits, and services for completion of this project. The Contractor shall be responsible for all damages to persons or property occurring as a result of the Contractor’s fault or negligence. The Contractor shall be responsible for all materials delivered and work performed until completion and acceptance of the entire work.

II. EXISTING SITE CONDITIONS

The seven existing units and mechanical equipment room were originally installed around 1990 and the units were replaced in 2003. In 2010, the freezer ceiling, wall, floor, and door panels were upgrade. Each of the seven existing walk-in refrigeration units are mechanically equipped with a paralleled condensing unit system. This type of system uses multiple compressors to stage capacity up or down in order to satisfy fluctuating load requirements. The existing paralleled condensing unit system is an outdated and failing system. The condensing units are stacked which requires heavy lifting during replacement. The existing lead lag controls for the paralleled condensing unit system are obsolete and malfunctioning. The area of the refrigeration equipment room, BN17, is limited on amount of available space for maintenance accessibility. BN17 does not provide adequate ventilation per VA HVAC design manual, pg. 6-179. The thaw box is undersized approximately 100 sqft to meet the facility’s demand. There are currently at least two water leaks above Freezer #1 and Freezer #2 area. One leak appears to be at an elbow of a hot water pipe and the other appears to be on a chilled water pipe.

The seven refrigeration equipment names, temperature, and room designation number are defined below.

· Refrigerator #1 (32 degrees to 36 degrees) – BN16A

· Refrigerator #2 (36 degrees to 40 degrees) – BN16B

· Refrigerator #3 (36 degrees to 46 degrees) – BN9A (Pharmacy Cache)

· Refrigerator #4 (36 degrees to 40 degrees) – BN25

· Thaw Box (32 degrees to 35 degrees) – BN16F

· Freezer #1 (-8 degrees to 0 degrees) – BN16E

· Freezer #2 (-12 degrees to -8 degrees) – BN16D

III. STATEMENT OF WORK FOR CONSTRUCTION

1. REPLACEMENT

Walk-In Cooler and Freezer replacement shall include all new freezer, thaw box and refrigerator panels (enclosure system), evaporators, condensing units, refrigeration systems/units, refrigerant lines, defrost units, electrical switches/wiring, lighting/light fixtures, alarms, controls, thermostats, gauges, conduit, wiring, piping, fire suppression, demolition, floor leveling and any associated controls programming and equipment. Contractor will replace the existing parallel condensing unit system and evaporators with a new state of the art split system design. Each system will have two compressors and two evaporators, all with 100% capacity, alternating their operation through a lead/lag controller. Use the project drawing equipment capacity as a basis of design to provide a fully functional split refrigeration system meeting box heat load calculations and space limitations within mechanical room, BN17/BN28.

2. TEMPORARY REFRIGERATION COVERAGE

Contractor will provide one 8’x10’ walk in cooler for VA NFS thaw box and one 8’x’10’ walk in cooler for pharmacy staff. Contractor shall be responsible for the continuous (24hr/7days a week) operation of refrigeration units. Contractor to provide monitoring and alarms of all temporary units to the engineer control center (ECC), building 3, room 9 as indicated on drawing. Contractor shall provide a temporary covered walkway for VA NFS & pharmaceutical staff at the ground floor level. As indicated on the project drawings, the VA placed NFS temporary units on the ground level near the back loading lock. The VA installed a lift platform to elevate the users approximately 3’ from the ground level to the dock level. Contractor will provide a covered pathway from the temporary units to the lift platform and provide an elevated coverage over the lift platform. The elevated coverage roof will be flushed with the dock roof and will extend over the adjacent temp unit. The walkway coverage roof will extend over the temporary units. The roof will prevent rain from getting into the units and provide adequate coverage. Install ramps for the temporary refrigeration units with a gradual slope.

As indicate on the drawing, pharmacy temporary unit will be located near the emergency departments entrance. Construct a ramp with a gradual slope and install handrails on both sides. All temporary covered walkways and ramps must be in place and functioning properly prior to the VA moving their items into the new temporary units. The VA will need 48 hours to move items into the new storage units, then the contractor will be allowed to move to infection control barriers. No additional progress is to occur until the VA has vacated BN28, BN17, BN16, BN16A, BN16B, BN16C, BN16D, BN16E, BN16F, BN9A and BN25. After project completion, remove all temporary coverages and ramps to restore site back to original condition.

3. INFECTION CONTROL BARRIERS OVERVIEW

Once the VA has vacated and turned over BN28, BN17, BN16, BN16A, BN16B, BN16C, BN16D, BN16E, BN16F, BN9A and BN25, the contractor shall start constructing infection control barriers. As indicated in drawing, contractor will install two different types of infection barriers to adequately meet the Infection Control Risk Assessment. The first 6mil fire retardant barrier is a temporary barrier until the completion of the second barrier. The second/primary barrier is a sheetrock wall to meet general specification 01 00 00. The first barrier must be at -.02 in wg or more negative while constructing the primary barrier. Do not start on primary barrier until first barrier has been inspected and approved by COR. Contractor will modify lights and miscellaneous building ceiling mounted devices to accommodate infection control barrier. In order to provide the minimum amount of clearance space as drawing indicates, contractor will construct barrier with specific dimensions at various locations. It is the contractor’s responsibility to use negative air machine sized according to volume demand. Install a magnehelic gauge on each primary control barrier. Gauge must be visible without having to enter into construction work area. Gauge must be capable of showing a positive and negative pressure displacement with the appropriate decimal place.

Contractor is responsible for all necessary infection control measures to include, but not limited to dust partitions, walk-off mats, establishing and maintaining negative pressure of the work area, daily clean-up and final cleaning upon project completion. Contractor shall be responsible for removing all items demolished from the station. Contractor to work in accordance with the Infection Control Risk Assessment provide and in accordance with the General Requirements, Safety Requirements and Construction Waste Management specifications provided.

4. DEMOLITON

A. PHASE 1 – BN17/BN28

Phase 1 demolition will establish and verify the safety precautions and life safety measurements required near a hospital’s active food service department. On the exterior side of mechanical room BN16, construct a primary infection control barrier. Request COR approval before proceeding.

After COR approves, contractor will proceed with secondary barrier in corridor BN39. Refer to sheet A-102 and AD-102 for more details. Seal BN16 door and remove two windows panes in the corridor for exhaust ductwork. Establish a secondary barrier in corridor BN39 by using the window opening to route exhaust ductwork. Ductwork will terminate as shown on drawing and exhausted air will not infiltrate temporary refrigeration units or facility. Negative air machine will continuously run in the corridor until VA inspects secondary barrier.

Once secondary is approved, proceed to primary barrier construction in corridor BN39. Ensure construction access door swings into construction zone and located per drawing. After COR approves primary barrier, contractor will take down the secondary barrier and start demolition in the office supply closet, BN28. Demolish storage closet wall from floor to ceiling, flooring, shelves, lights, light switch, door, frame, and hardware to prepare space for new work. BN17 and BN28 ceiling have a slight height difference so modifications, ceiling repair, and painting may be required after demo work. Demo BN17 wall, exhaust fan, louver, door, frame and hardware to prepare for new door and additional new HVAC work. Coordinate salvaged material with COR before disposing. Proceed to phase 2 demolition after COR approves phase 1 demolition.

B. PHASE 2 – BN17

Contractor will maintain a negative pressure in both BN17 and BN39 construction barrier by using two separate negative air machines. Contractor will infill the two door openings. Construction will match existing glazed CMU wall. Contractor will ensure the glazed CMU wall are filled evenly. Contractor will be required to remove and replace CMU wall if quality of work is found unacceptable by the VA.

C. PHASE 3 – BN16

Contractor will create an anteroom to ensure BN39 construction barrier meets -.02 negative. To create anteroom, use a zip barrier to replace BN16 door. An independent negative air machine will serve the anteroom. Additional negative air machines will continuously run in BN16 and the zip barrier will accommodate BN16 exhaust ductwork routing. Route exhaust duct as drawing indicates. Request VA to inspect and approve work before proceeding.

Demolish BN16 existing door and remove wall and electrical switch to accommodate expanded door as indicated in new construction. Remove existing refrigeration control panel in corridor BN39. Completely remove walk in units for Refrigerator and Freezer #1 and #2 and thaw box and remove all piping, conducts, and associated equipment to prepare for new construction.

Once the existing boxes are demolished the VA will need to do an assessment of any existing utilities in the space for disposition in an effort to prevent future utility issues above and around the new units. If existing utilities are found that pose a concern, this will be considered a “differing site condition” and a contract modification will be required to relocate the utility or system out of the way. Contractor to investigate and repair leaks, repair piping and reinsulate. Contractor shall notify the VA immediately if any other leaks or water sources are found in any of the work areas. Contractor shall not proceed until the VA has inspected the area.

D. PHASE 4 – BN9A/BN25

Negative pressure will be accomplished by routing exhaust ductwork from the construction area to outside of the facility. Fasten ductwork to ceiling and route ductwork through the existing windows above the two sets of exterior double doors. Ductwork will terminate as shown on drawing and exhausted air will not infiltrate temporary refrigeration units or facility. Refrigerator #3 and Refrigerator #4 will share the same exhaust truck and contractor must ensure both exhaust fans are running simultaneously during demolition and construction. Contractor will stop work if either fan is not running.

Use exhaust ductwork as described above to construct a secondary barrier. Request inspection before proceeding to primary barrier. After approval, construct primary and install doors per drawing and size doors accordingly. Clearance space must be maintained as drawing indicates. Completely remove walk in units for Refrigerator #4 and #5 and remove all piping, conducts, and associated equipment to prepare for new construction. See drawing for more details. Allow VA to inspect and check for leaks. Contractor shall not proceed until the VA has inspected the area.

5. NEW CONTSTRUCTION

A. SPLIT UNIT SYSTEM

Contractor will provide a redundant refrigeration system by using a split refrigeration system for all 7 boxes. Each box will use a split system so that should one system fail, the system will have enough capacity to help it hold temperature for as long as possible until the system can be serviced. Provide a lead lag control system for each box. The system will utilize a predictive control algorithm and staging delay timer to sequence the system’s compressors, matching the conditioned space’s load requirements. The staging control algorithms will equalize the system compressors’ operating hours. The control system will prevent unnecessary multiple compressors start/stop cycles, provide duty cycles and ensure the cycles required for proper oil management. The controller will prevent demand surges from multiple compressors starting at the same time. As identified on sheet M-103, all compressors must be scroll compressors, all evaporators must include electric defrost, and each system is equipped with a lead lag controller. The schedule is provided as a basis of design.

Contractor will submit an equipment layout for the redundant system using the sheet M-101 and M-102 as a concept. Contractors’ layout must adequately utilize the space in the expanded mechanical room as much as possible and provide appropriate service clearances for the redundant condensing units and evaporators. Contractor to verify redundant evaporator locations and address pipe and electrical routing as required. Install accessible isolation valves for the chilled water supply and return risers and branch pipes in BN17. To minimize unnecessary down time, provide isolation valves for the condensing unit equipment so that each of the condensing units can be isolated for maintenance or repair while keeping the refrigeration/freezer unit in operation by the redundant system. All equipment shall be circuited to existing panel BPC 1 and BPC 2. BPC 1 will sever evaporators and condensing units. BPC 2 will serve everything else related to project. See electrical scope of work and drawings for more details.

Contractor is responsible for routing and core drilling new refrigerant lines and removing old refrigerant lines from mechanical room to refrigeration boxes through the sub-basement. Contractor shall seal any openings within the spaces identified in this project in accordance with code/fire rating (i.e. concrete deck, walls). Condensate drain piping in freezer compartments shall be heat tape and installed under insulation for complete length of run within freezer. Insulate all pipe per specification and manufacturer recommendations.

B. BUILDING AUTOMATION SYSTEM

Provide wiring, controls, alarms and associated work for continuous monitoring of the temporary units and new system at the Boiler Plant, Building 3, Room 9. The control package will include remote alarm notification and the alarm will trigger at high mechanical room temperature, high and low refrigeration walk in cooler room temperature, and control panel power loss. Provide an enclosed cabinet such as a NEMA 4 with adequate space to protect the control system. Install a new temperature monitoring station to replace the existing one in the BN20 corridor. Each box shall have a lock in switch alarm that alarms locally in the hallway and at the Boiler Plant. Install a water leak detection system and a refrigerant leak detection system in BN17 and tie it into the front-end building management system in the Boiler Plant. See additional work described in section 5.D, Mechanical Room – HVAC.

C. MODIFCATIONS FOR NEW CONSTRUCTION

The new lay out of the boxes shall be comparable to their current size but also include at a minimum 100 additional SF of space within Thaw Box, BN16. Relocate electrical and data outlets and modify ceiling track and tile and other elements to accommodate thaw box expansion. As indicated in phase 1 demolition, construction will incorporate making BN17 accessible from the back-dock area. Install new lights and switch per drawing sheets. Provide new door, frame, and hardware for all doors per drawing schedule.

Construction will also incorporate expanding BN16, nutrition dry storage, entry doorway to accommodate a 4’ wide door. Make any necessary adjustments such as relocating light switch, modifying and replacing handrails, and other modification needed to prepare space for new door. Provide new door, frame, and hardware per drawing schedule. Contractor shall seal any openings within the spaces identified in this project in accordance with code/fire rating (i.e. concrete deck, walls).

D. MECHANICAL ROOM – HVAC

HVAC work will be installed after refrigeration system is completely installed and approved by VA. By installing HVAC afterwards, the contractor and VA can finalize a layout plan due to limited space in mechanical room. Provide a new ventilation system for the mechanical room, BN17. This will be accomplished by using a new fan coil unit and exhaust fan. Support the fan coil unit, exhaust fan, registers and grills from the ceiling. Route ductwork as drawing shows and ensure ductwork does not interfere with sprinkler coverage and maintenance accessibility. Provide dampers for each branch for adequate air distribution. Provide a programmable unit controller with digital thermostat and valve actuator. Tie into chill water lines and install isolation valves for supply and return. Route condensate to drain in the mechanical room.

The dedicated exhaust system will capture heat over refrigeration condensing units. This exhaust shall activate by a high space temperature set point and the system shall notify the ECC. The exhaust shall also activate by refrigerant leak detection system. Upon activation by leak detection system, the air shall be exhausted to outdoors and fan coil unit shall be capable of operating 100% outdoor air during emergency refrigerant evacuation mode. The BAS shall notify the ECC once a leak is detected. Provide actuated dampers, HVAC controls, and any necessary components to facilitate system operation in normal and emergency modes. Route exhaust fan ductwork outlet to the north side of the building by penetrating the dock roof and ensure ductwork terminates 25’ from any air handling unit. Provide watertight seals at rooftop and exterior wall penetration. Provide registers, louvers and grills per duct opening and manufacturer recommendation. See sheet M-102 for more details. A certified test and balancing contractor must commission and provide a test report after installation.

E. ELECTRICAL

The electrical power connection schedule shown on E-104 is a conceptual plan. Once VA approves final submittal of refrigeration equipment, contractor shall work closely with a certified electrician and OBVA to verify and install the appropriate wiring, breaker sizes, and disconnects as required for the redundant refrigeration system and all construction work. The power connection schedule will be finalized after receiving final manufacturer equipment specifications. Contractor must ensure panel BPC 1 and BPC 2 are adequately accessible by verifying condensing unit equipment layout. Electrical contractor will modify light locations to accommodate infection control barriers and modify electrical element locations for thaw box and doorway expansions. BPC 1 is a 400 amp panel and it may have capacity for all refrigeration equipment. BPC 2 shall be used if BPC 1 doesn’t have the capacity for all units. Refer to all drawing sheets for more details.

6. CONSTRUCTION AND PRODUCT SUBMITTALS

Refer to specification 11 41 21 Walk-In Cooler and Freezer for requirements such as panel construction, insulation, door hardware, pressure relief ports, floor panels (as required), lights, rub rail wall protectors, and monitoring alarm system. Provide submittals in accordance with the Shop Drawings, Product Data & Samples Specification. As defined in specification, contractor will submit for approval product details identifying performance requirements, construction requirement, unit cooler specifications, monitoring alarm system, equipment identification, refrigeration split system, and warranty requirements.

Contractor will confirm equipment layout in mechanical room with refrigeration contractor. If layout must be modified, submit layout for VA review and approval. Contractor will execute a successful installation by conducting initial start-up and operational test, performance tests reports, and pressure testing and various commissioning process per VA specification and manufacture recommendations.

Contractor shall provide shop drawings for all refrigeration equipment and location, HVAC equipment, isolation valves, light fixtures, assembly drawings, start-up and testing procedures, manufacturer warranty/guarantee certificate, and all new equipment to be installed.

7. VA REQUIREMENTS

Contractor will be working in a functioning hospital and adjacent to nutrition food service department. Contract shall not impact the operations of the hospital and kitchen. Refrigerant must be recovered prior to freezers/refrigerators being dismantled by an EPA Certified technician using EPA certified equipment. Proved copy of reclaimed refrigerant sheet to the VA. Contractor shall follow all applicable Federal, State & Local Codes.

8. ASBESTOS ABATEMENT

Reference Sheet G-002 – Asbestos Survey. There asbestos containing material (ACM) on piping in various location. Contractor shall abate this ACM in accordance with VA Asbestos specification as applicable and reinsulate piping.

9. INSTALLER QAULIFICATIONS AND SYSTEM REQUIREMENTS

All mechanical equipment shall be installed by a licensed mechanical contractor. In order to properly maintain and service this type of system, contractor must use a local refrigeration contractor who is accustomed to servicing the supermarket or commercial refrigeration industry. Contractor shall ensure that the new thaw box, refrigerators and freezers are installed in accordance with the manufacturer’s recommendation and by a certified manufacturer’s installer. Contractor shall provide written proof of certification prior to start of work. Installer shall have 10 years’ experience installing similar size units/systems and shall provide references of 3 installations within the past 5 years. Upon completion of the installation the contractor shall provide certification of the units. Contractor shall provide a 10-year manufacturer’s warranty on materials, panel installation, assembly and seals and a 5-year refrigeration warranty and a 3-year service warranty. Contractor shall provide a copy of the total refrigerant (EPA refrigerant) logs per system.

10. WORK HOURS

The majority of work shall be accomplished between the hours of 7:00am to 4:30pm Monday through Friday (excluding federal holidays); however, the contractor may be required to accomplish some work after hours or on weekends to minimize disruption to hospital operations. All work shall be coordinated with the COTR.

11. PERIOD OF PERFORMANCE

Performance period for this contract shall be 180 days for construction from NTP date.