B09-Amd002-_RFIs_8-28_0002.docx

COLO HVAC – 140P4326R0025

Amendment 002 RFIs 8-28

Technical Clarification Questions

8. Zoning System Status

· Is the existing zoning board intended to remain in place under this scope of work? Government Response: NO

9. Zone Damper Configuration

a. Should the zone dampers be maintained in their current state, or is the intent to force them to remain fully open or fully closed? Government Response: ZONE DAMPERS SHOULD OPEN AND CLOSE, CURRENT STATE NON OPERATIONAL

b. Clarification is requested, as there has been discussion regarding forcing the dampers either open or closed. Government Response: SEE PREVIOUS

10. Equipment Manufacturer Requirement

a. The SOW states that a Trane unit or an equivalent may be proposed, and that equipment should be from the same manufacturer. Government Response: EXISTING IS TRANE, WHATEVER MAUFACTURER PROPOSED SHOULD BE Manufacture OF ALL NEW EQUIPMENT

b. Does this requirement apply to both the indoor air handling unit and the outdoor condensing unit, requiring both to be from the same manufacturer? Government Response: YES Technical Issues Identified

11. Return Bypass Damper Absence

· There is currently no return bypass damper installed. Government Response: NO; ONE IS NOT INSTALLED

· All three zones are currently forced open. Government Response: YES

· If a single zone calls independently, the resulting static pressure in the supply duct may become excessively high, potentially causing system performance issues due to the lack of pressure relief. Government Response: THE SYSTEM SHOULD PERFORM AS A TYPICAL HVAC SYSTEM, NO ADDITIONAL DEHUMIDIFICATION OR HUMIDIFICATION IS REQUIRED

12. Air Handler Size Constraint

· The existing air handler is a 3.5-ton unit with a width of 26 inches. Government Response: PHOTOS SHOW MODEL SERIAL #, these are in the SOW.

· Replacement equipment would require duct modifications, as new standard air handlers are approximately 21 inches wide. Government Response: YES

· This would necessitate refabrication of existing ductwork to accommodate the new unit size. Government Response: YES

13. Refrigerant Line Set Compatibility

· The existing refrigerant line set is sized at 3/4” (suction) and 3/8” (liquid). Government Response: YES

· A new 3-ton system would typically require 7/8” (suction) and 3/8” (liquid). Government Response: REFER TO SOW, IF NEW LINE SET IS NEEDED PER RECOMMENDATION NEW LINE SET WILL NEED NEW LINESET

· Therefore, the existing line set would likely require replacement to ensure proper system performance. Government Response: SEE ABOVE

14. Thermostat and Humidity Control Limitation

· The current system uses wireless thermostats communicating with a zone control board. Government Response: YES

· As configured, dehumidification and humidification functions cannot be properly controlled or achieved through the thermostats alone. Government Response: THE SYSTEM SHOULD PERFORM AS A TYPICAL HVAC SYSTEM, NO ADDITIONAL DEHUMIDIFICATION OR HUMIDIFICATION IS REQUIRED

· Additional controls or system modifications would be required to support these functions. Government Response: N/A

Technical & Equipment Questions

15. Efficiency Standards: The SOW asks for a "high efficiency equivalent" condensing unit. Does the NPS have a specific minimum SEER2 rating requirement for this project? Government Response: 17 SEER OR BETTER

16. Refrigerant Lines: The SOW mentions flushing the line set if not replacing it. Based on the age of the existing unit (manufactured in 2004, per Page 9), if the existing lines are the wrong size for modern high-efficiency equipment, is the replacement of the entire line set considered part of the Base Work or a change order? Government Response: PART OF BASE WORK

17. Condenser Elevation: It is required to elevate the unit 4 inches above the current pad. Is a specific type of riser (e.g., plastic "pump ups" or a new concrete/composite pad) required to maintain the aesthetic of the historic site? Government Response: EITHER OPTION

18. Zoning Compatibility: For Option 1, if the "same manufacturer" requirement applies to the HVAC units, must the new Zone Panel also be the same brand (e.g., a Trane/American Standard zone panel) or can it be a third-party commercial grade panel like Honeywell? Government Response: CAN BE THIRD PARTY AS LONG IT FULLY FUNCTIONS WITH SYSTEM

19. Heat Strips: The SOW specifies a minimum of 8kw heat strips. If the new equipment manufacturer offers 7.5kw or 10kw as their standard increments, which is preferred? Government Response: AT LEAST 8 SO IN THIS OPTION 10KW. 90 AMPS AVAILABLE ACROSS 2 CIRCUITS Historic & Site Constraints

20. Structural Sensitivity: Since the building was built in 1732, are there any restrictions on drilling new penetrations through the brick or interior walls for line sets or thermostats? Government Response: YES, ANY NEW PENETRATIONS ARE PROHIBITED

21. Basement Access: The SOW mentions an additional basement. Is the air handler located in the basement or on the second floor? Are there narrow staircases or tight clearances that would limit the size of the replacement equipment? Government Response: NO, NO EQUIPMENT IN BASEMENT

22. Dispatch Center Operations: The building serves as a dispatch center and will be occupied. Can the HVAC system be shut down for a full workday, or must the contractor provide temporary cooling/heating during the transition? Government Response: IT CAN BE SHUT DOWN

23. Power Interruption: Since this is a dispatch center, is there a specific protocol or advanced notice required (e.g., 48–72 hours) before the electrical service disconnect is replaced? Government Response: YES, PRIOR SCHEDULING IF THE BUILDING ELECTRICITY IS COMPLETELY SHUTDOWN Option 1 & Control Questions

24. Thermostat Features: Does the NPS require the "Commercial Grade Thermostats" to have Wi-Fi connectivity or remote monitoring capabilities for park facilities management? Government Response: NO

25. Existing Damper Condition: If the existing dampers are found to be non-functional during the installation of the new zone panel, is the repair/replacement of those dampers covered under "Ensure operation of current dampers," or is that an extra cost? Government Response: YES Closeout Questions

26. Submittal Format: For the "Cut-Sheet Binder," is a digital PDF version acceptable in addition to or instead of a physical binder? Government Response: DIGITAL IS OK

27. Section 1.01.B states that “All newly installed equipment must be of the same manufacturer.” Can the Government please clarify this requirement? Does this mean that the replacement equipment must be manufactured by Trane to match the existing system, or may offerors propose equipment from another reputable manufacturer (e.g., Carrier, Lennox, etc.) provided that the new indoor and outdoor units are a matched system from the same manufacturer? Government Response: DOES NOT HAVE TO BE TRANE, NEW UNITS MUST MATCH AND FULLY OPERATE TOGETHER

28. Regarding bonding requirements, the solicitation does not appear to expressly require a Bid Bond, Performance Bond, or Payment Bond in the Standard Form. However, the solicitation includes FAR 52.228-2, Additional Bond Security. Can the Government please confirm whether any bonds are required for this project? If so, please specify:

a. The type of bond(s) required (Bid Bond, Performance Bond, and/or Payment Bond); Government Response: Performance Bonds and Payment Bonds are not required for this action.

b. The required bond amount or percentage of the contract value; and Government Response: If bonds are required at time of award, it would be 100% of contract obligated value.

c. The timing and deadline for submission of the required bond(s). Government Response: If bonds are required at time of award the bonds would need to be provided 10 days after contract award.