RFI Responses_BDOC Chilled Water System Repair.pdf

1. Existing CRAHs o What are the flow requirements (GPM) for the existing CRAHs?

25.5 GPM

o What is the design entering-water temperature for the CRAHs?

44 °F o Please confirm the existing CRAH supply and return piping sizes are 2".

1 ½” o Can the existing piping be reused?

Yes o Are the existing isolation valves for the chiller and CRAH units operational?

Yes o Are strainers and check valves required per the manufacturer’s recommendations?

Yes, based on existing chilled water distribution. Strainers and check valves are in pump house and near CRAHs.

o The sheet metal serving the CRAHs will need to be reconfigured since Data Aire no longer supports the existing model. Please confirm.

Project has been descoped no longer requiring the CRAHs to be replaced.

2. Existing Chiller o Please confirm the existing chiller is 20 tons, with two circuits at 10 tons of capacity each.

Yes, the unit is 20 tons, with two circuits at 10 tons.

o Please confirm the existing chiller supply and return piping sizes are 2".

The chiller supply and return piping is 1 ½” o Can the existing electrical service be reused?

Yes, given the existing electrical is compatible with the new chiller.

o Is the existing power feeding the chiller and CRAHs connected to generator power?

Yes. Chiller and CRAHs are connected to generator power.

3. Glycol System o Please confirm the required glycol concentration/type.

30% propylene glycol o Please provide a glycol feeder detail that meets Buckley’s requirements.

The glycol feeder shall satisfy all applicable requirements in UFC 3-410-01 (emphasis on Sections 1201.6 and 1207.3) as well as the International Mechanical Code (IMC) (emphasis on Chapter 12). Basis of Design: Wessels Model GMP-13050.

o What is the estimated volume of glycol currently in the piping so we can complete a material takeoff?

~55 Gallons.

o Does the existing system have a makeup-water feed?

Yes. Make-up feed is in the mechanical room.

4. Controls o Per the site walk, the BAS controls are not part of this project and will be contracted separately under a different project. Please confirm.

The chiller does need to be integrated for alarms, chilled water supply, chilled water return, compressor run time and cooling capacity. We would like all the points available for view.

5. Labor Requirements o Does this project require certified payroll? If so, please provide the applicable prevailing wage rates.

No

6. Site Access / Security o Will Buckley provide space and personnel to support required escorts for the project?

Yes. Buckley will provide escorts if required. Project has been descoped no longer requiring the CRAHs to be replaced.

o Are the existing walls SCIF-rated and/or fire-rated, and will any of these walls need to be demolished to allow installation of the new CRAHs?

Project has been descoped no longer requiring the CRAHs to be replaced.

o Can Space Force provide support with demolition/removal of the security doors if the new CRAHs will not fit through the existing openings?

Project has been descoped no longer requiring the CRAHs to be replaced.

7. Hot Work / Server Equipment o Can hot work be performed within the data center while the existing server equipment remains in operation?

Project has been descoped no longer requiring the CRAHs to be replaced.

o Can the servers be temporarily relocated, if necessary, to allow installation of the new CRAHs?

Project has been descoped no longer requiring the CRAHs to be replaced.

8. Temporary Cooling o Temporary cooling is currently installed due to the failed chiller. Please confirm that temporary cooling is not required as part of this project.

Project has been descoped no longer requiring the contractor to provide temporary cooling.

9. Seismic / AT/FP Requirements o Per AT/FP requirements, is a seismic engineer required to review the installation and provide stamped calculations?

Yes. Refer to UFC 3-301-01 and ASCE-7.

o Are spring isolators required for the new chiller?

Vibration isolators are required. Per UFC 3-410-01, Section 1-23.1, refer to the ASHRAE Handbook—HVAC Applications (Emphasis on chapter "Noise and Vibration Control") or the manufacturer’s recommendations for all vibration isolation design requirements.

o The existing chiller does not appear to meet this requirement. Please confirm the requirements for the replacement equipment.

Yes. Seismic and Vibration isolator requirements apply for the new chiller.

10. Design Requirements o Please confirm whether this project is design-build.

Yes.

o Is a PE required to stamp the design drawings?

Yes.

11. Schedule / Lead Times o The chiller and CRAHs currently have approximately six-month lead times with BAA-compliant equipment. Please advise whether the Period of Performance (POP) can be revised to accommodate the current equipment lead times.

Yes, the POP was revised to accommodate equipment lead times.

RFI-001: Load Calculation & Capacity Verification What is the exact current server room heat load, or alternatively, what is the current critical IT power usage (kW) in the room from which the thermal load can be inferred?

Sizing will be determined by the existing Chiller, CRAHs, and system sequence of operation.

RFI-002: Performance Period Timeline & Temporary Mitigation The SOW requires full project completion within 30 days ARO. Given that standard custom industrial lead times for low-temperature Trane chillers sit at 14–20 weeks and Liebert air handlers require 8–12 weeks, a 30-day permanent installation is physically impossible. Will the Government allow the deployment of temporary rental cooling on-site within the 30-day ARO window to maintain data center operations while the permanent equipment is being built at the factory?

The POP will be revised to accommodate equipment lead times. Additionally, base provided temporary cooling will be utilized. The SOW will be descoped no longer requiring contractors to provide temporary cooling.

RFI-003: Site Access Expansion This project was solicited over a holiday week (August 26) with the primary site visit scheduled immediately after on September 1. Due to this compressed window, will the Government schedule a second formal site visit, or alternatively, can cleared contractor personnel access the site independently to evaluate the exterior chiller footprint and piping?

No. The Government will not be having a second site visit.

RFI-004: Physical Clearances & Architectural Boundaries The existing concrete equipment pad measures approx 20' L x 12.5' W with a 12,000 lbs capacity, which safely accommodates the weight and frame size of the Trane Chiller.

However, required ASHRAE 15 and factory maintenance clearances dictate a total operational width envelope of approximately 12.2 feet. Please confirm if there are any permanent architectural walls, security fences, or structural obstructions within 4 feet of the existing pad edges that would violate these equipment airflow or safety clearance boundaries.

No permanent architectural walls, security fences, or structural obstructions within four feet of the existing pad edge. Confirm clearances outlined in ASHRAE Standard 15 and the International Mechanical Code (IMC) regarding A2L refrigerant-charged equipment when determining new chiller location.

RFI-005: EMCS Software Device Licensing & Existing Supervisor Capacity The notes require the contractor to provide a Niagara 4 supervisor license upgrade plus an additional 10% point buffer. Please provide the current model, license capacity, brand ID, and core software version of the existing host N4 Supervisor to ensure the license upgrade can be properly sourced and applied without compatibility conflicts.

This was eliminated from the scope as we have a Tridium Niagara 4.15 supervisor license.

RFI-006: Controls Communication Protocols & Network Drops Does the facility EMCS network require BACnet/IP (Ethernet) or BACnet MS/TP (Serial RS-

485) for the CRAH controllers? If BACnet/IP is required, will the Government provide the necessary network drops, patch panels, and static IP addresses adjacent to the new PSH600-UPS JACE enclosure locations?

The facility currently has Delta controls BACnet/IP and this would need to be integrated to talk with the N4 Supervisor, the government will assign a static IP for the new installed controller the equipment needs either a JACE or a Niagara Native communicating controller.

RFI-007: Hydronic Loop Fluid Flushing & Charging Please confirm if the contractor is required to flush the existing chilled water piping loop and provide a fresh charge of industrial glycol fluid, or if the current fluid is to be reclaimed and reused.

The contractor shall flush the chilled water distribution and recharge with a 30% propylene glycol and water solution.

RFI-008: Environmental & A2L Safety Compliance Because the new Trane Chiller operates on next-generation R-454B (an A2L mildly flammable) refrigerant, does the existing outdoor equipment footprint satisfy all ASHRAE Standard 15 safety clearance requirements, or must external leak detection sensors and safety systems be provided under this contract?

Existing equipment footprint appears to satisfy ASHRAE Standard 15 safety clearances.

Confirm clearances outlined in ASHRAE Standard 15 and the International Mechanical Code (IMC) regarding A2L refrigerant-charged equipment when determining new chiller location.

RFI-009: Device Inventory Access & Pre-Existing Defective Assets The notes mandate a 100% final commissioning report and instant reporting of defective equipment across all existing facility mechanical equipment (boilers, AHUs, RTUs, VAVs, FPBs). Will the Government provide full engineering data sheets, prior TAB reports, and immediate programming access to these existing sub-controllers during the submittal phase so that baseline functionality can be verified prior to full network integration?

Yes. The government will provide all available documentation to verify baseline functionality.

RFI-010: Point Maps for Pre-Existing 3rd Party Equipment To comply with the requirement that 100% of points for third-party equipment (boilers, generators, VFDs) be integrated into the EMCS, please provide the manufacturer make, model, and existing BACnet card availability for all non-HVAC assets currently in scope. If an existing asset lacks a BACnet board or open protocol card, should the procurement of that hardware module be factored into this contractor's base bid?

Yes, it will need to be factored into the bid for fully open system.

Would you be able to provide a submittal for the current chiller for RFQ FA254326Q0027 so we can make the right selection?

See attached chiller submittal.