A004 RFI Response 2022-08-23 - CMO.docx

United States Department of Agriculture

Research, Education, and Economics Agricultural Research Service

Aug 23, 2022

IN REPLY

REFER TO: Replace Chiller at The Foreign Disease-Weed Science Research Unit (FDWSRU), Ft. Detrick, MD Solicitation # 12305B22Q0115

Questions and Answers

1. SOW states “Deteriorated insulation, piping and valves must also be replaced.”. Please be more specific as to how much piping is to be replaced above ground and in the basement mechanical room? Are all mechanical piping, valves and insulation associated with the non-functional chiller & pumps to be replaced?

ANSWER: 1) All piping from junction of new chiller with old into building 1302 and associated valves is to be replaced. This is approximately 118’ of supply & return piping (ea.). All piping is above ground only. Valves to be replaced are in the basement. Interior piping and insulation are to remain intact. New exterior piping is to be installed with top of pipe elevation of not less than 30” above grade. New pipe supports are to be included. An automatic air bleed vent valve is to be installed at piping high points. A manual drain gate valve is to be provided at piping low points. Contractor is to ensure that the piping connections to the chiller skid are properly supported and without strain, and contractor is to provide strain relief (such as flexible piping segments) in piping design.

2. Is heat trace required for the new chilled water piping exterior of the building?

ANSWER: 2) Yes. The system coolant is untreated water. Since the chiller is an outdoor installation, the entire system is to be freeze tolerant/ protected from freezing without damage.

3. Is the confirm contractor to match existing insulation type & thickness – i.e. aluminum jacketing exterior, non-removable pump boxes?

ANSWER: 3) No. Piping insulation is to be suitable for exterior chilled water service. Insulation is to be not less than 1.5” lightweight, rigid cellular glass insulation or approved equivalent with insulation joints fully sealed. All insulation joints are to be sealed with a polymer-based sealant. Insulation is to include a vapor barrier and to be covered by protective aluminum cladding.

4. Given that the lead time for a 56-ton York air-cooled chiller is approximately 40-weeks, will the Period of Performance be modified to accommodate equipment availability?

ANSWER: 4) The period of performance reflects a time based on the work required. Vendors should propose their own Schedule as part of the Eval criteria Factor 5 – Schedule - Provide a proposed delivery schedule for the Chiller unit.

5. Is the contractor to expand the concrete pad for the York chiller?

ANSWER: 5) The new chiller is to be set 8” (min.) above existing pad grade. Contractor is to provide additional curbing on top of existing pad. Curbing may be reinforced concrete with rebar, pressure treated timber, or other. Curbing is to meet equipment manufacturer’s specifications for curbing. Contractor is to submit curb design proposal.

6. Is all work to occur during normal business hours – 6 am to 3 pm.?

ANSWER: 6) Business hours are 8 AM to 4:30 PM. Work is to be typically performed during normal business hours; however, tie-ins to existing piping and electrical are to be coordinated with site and may need to occur during off-hours. Outdoor work may be scheduled to be performed outside normal business hours.

7. Is this contract to provide testing and balancing? Note: SOW paragraph 3 says “contractor shall test system upon installation of components”. Is a formal TAB and report required?

ANSWER: 7) This chiller system primarily serves processes and not occupied space; no traditional TAB is required. However, contractor is to start-up and commission the system. Contractor is to bleed the system of air. Contractor is to provide temporary screens in water piping upstream of chiller and remove said temporary screens upon completion of startup activities. Contractor is to attest that motor rotations are correct. Chilled water flow rates and temperatures are to be measured and chilled water balancing valves to be adjusted. Contractor is to demonstrate that pumps, chiller, and controller operate as intended. A chilled water balancing report is to be generated.

8. Is pricing to include pumps, all valves, and all associated insulation?

ANSWER: 8) Yes.

9. Is there a preferred vendor for the chilled water pumps (Not mentioned in SOW)?

ANSWER: 9) No preferred vendor has been identified.

10. Is there another way to access the basement besides the ship ladder? That is, is there a regular set of stairs?

ANSWER: 10) Elevator inside building, no other stairs.

11. Does the control panel report back to a base-wide BAS (Not mentioned in SOW)?

ANSWER: 11) No.

12. Is there a specification for the Johnson Controls system (Not mentioned in SOW)?

ANSWER: 12) For reference: The existing chiller is an air-cooled scroll compressor chiller model YLAA (or equivalent) with not less than 56 ton chilling capacity, 460v-3φ-60Hz-150a circuit, with EWT of 54 F and LWT of 44 F at design of 136 gpm water.

13. Should the alarm light tie into the panel and tie into the possible BAS or is it local only? Is the alarm light visual only (Not mentioned in SOW)?

ANSWER: 13) The alarm light is local only. The alarm light is visual only in building 1302 (see SOW). The Hallway Status Alarm Light is to be a light stack (RED/Yellow/Green) in the hallway to indicate fault, alarm, and normal status.

14. Who is the JCI point of contact?

ANSWER: 14) The Johnson Controls point of contact is:

Matthew Murphy, Matthew.P.Murphy@jci.com .

15. What is the sequence of operations for the controls (Not provided)?

ANSWER: 15) The new chiller is to be part of an existing primary-secondary control scheme. Chilled water is to circulate continuously. Control system is to start automatically upon power-up after power loss. Upon increase in chilled water discharge temperature, secondary chiller is to start. Upon drop loading of secondary chiller, the secondary chiller is to stop. Primary and secondary chillers are to alternate automatically based on user input schedule.

Install the following points (at a minimum) are to be monitored and trended:

· Entering Water Temp

· Leaving Water Temp

· Chiller Pump Request/Isolation valve status

· Outside Air Temperature and Humidity

· Pump Status

· Run time

16. Will equipment need to comply with Buy America Act requirements? This adds several weeks to the fabrication lead-time. If yes, please provide applicable FARS clauses.?

ANSWER: 16) Yes, refer to the Solicitation Docs.

17. Does the existing chiller/chilled water system contain glycol? If so, what is the type and concentration?

ANSWER: 17) No, the system does not contain glycol (although this may be added in the future). And, since this is an outdoor installation, the entire system is to be freeze tolerant/freeze protected.

18. Is an extended chiller warranty is to be included (standard warranty is 12 months on unit, not to exceed 18 months from shipment)? Extended warranty can be provided for the compressors only, or for the entire chiller?

ANSWER: 18) An extended warranty is quoted as an option.

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