RFI LOG W50S8524B0002 as of 15 May 24.pdf

RFI LOG W50S8524B0002VGLZ 212001 REPAIR SIMULATOR HEATING, VENTILATION, AIR CONDITIONING B34

Q1 Are there any “Brand Name Jus�fica�ons” for the equipment listed on Sheet M-701?

A1. No there are not any brand name jus�fica�ons beyond that for the DDC system. The Contractor is instructed to assure any new system is compa�ble with ours. That can be done by other systems.

Q2 Regarding B34 simulator project transformer, it has a lead �me of 80-120 weeks + 16 weeks of shop drawings prepara�on + Govt review and approval �me. Project will go substan�al past the allocated POP. Please review and revise.

A2: There are no transformer requirements. The project descrip�on paragraph in SECTION 00 21 00 INSTRUCTIONS, CONDITIONS, AND NOTICES TO OFFERORS has been updated via Amendment 01.

Q3Specifica�on sec�on 051200 Sec�on 1.6 A and B indicate to u�lize a contractor that is cer�fied by AISC as a cer�fied erector. At this moment, there are only 15 companies in the en�re state that are cer�fied by AISC as an erector, and most if not all of them are extremely busy. This requirement would increase costs to the project drama�cally, and poten�ally out of the threshold. Please confirm if we can u�lize other qualified contractors that do not cer�fy themselves with AISC?

A3. The requirement for an AISC cer�fied erector is deleted as per amendment 2 of the subject invita�on for bids.

Q4Specifica�on sec�on 236423.13 Air cooled chillers, sec�on 2.1 B. indicates for zero percent performance tolerance in lieu of AHRI 550/590. Please confirm if the tolerance is zero, or if a typical 5% plus or minus is required?

A4. AHRI 550/590 Chapter 5 defines 2% as the upper limit for capacity tolerance of the chiller. Follow

AHRI 550/590.

Q5Specifica�on sec�on 236423.13 air cooled chillers, indicates to provide integral pumps, however pumps are already being provided in the mechanical room for this chiller. Please advise?

A.5. There are no internal chiller pumps to be provided. See drawings for pump loca�ons.

Q6Sheet M-701 - The chiller schedule indicates to provide a chiller with integral water storage tank. This requirement adds substan�al addi�onal costs and lead �me to the unit. Can the water storage tank be installed separately within the mechanical room?

A6. Yes, as per Drawing M301, ET-3 serving the chilled water system is in the mechanical room. 5/15/24 Update: It was determined that the mechanical room doesn't have sufficient space for the storage tank.

The Contractor shall provide the chiller with integral water storage tank as specified on the drawings”, Q7Based on the es�mated �me of award, submital approval, and lead �mes, the new chiller for this project will be the new R454B refrigerant in lieu of R410a shown in the schedule. Please confirm and acknowledge.

A7. Response: R454B refrigerant is acceptable.

Q8. Please provide any current warran�es on the roof.

A8. They have been provided with this RFI document. The exis�ng roofing system does have a roof warranty and the warranty needs to be maintained a�er the roof repairs have been completed.

Contractor to verify with government which roofing manufacturer is responsible for the roof warranty or guarantee. Subcontract all cu�ng and patching to the roofing manufacturer's approved local contractor.

Provide the government with a leter confirming his authority to perform such work prior to commencing the work and provide leter confirming work was done correctly and the exis�ng warranty has been maintained. See Drawing A-201 and MD-202 for addi�onal informa�on.

Q9Sheet M-201 note 12 indicates to test and rebalance exis�ng water source heat pump system serving remaining por�ons of the building. Please provide drawings on the equipment atached to the rest of this system.

A9. Provided are the latest HVAC as-builts we could find for B-34

Q10.Sheet E-301 note E4 indicates to provide an electrical shunt trip breaker to shut down each mechanical ven�la�on unit. Please confirm we are only shu�ng down our (2) new hvac units? Please also confirm if the intent is to kill the main 480v feed, or if this is intended to be ran and shut down via the bms system?

A10. All the shunt informa�on appears to be included on drawing E-301. Several are indicated in the ‘HVAC EPO DIAGRAM’. The M series drawing should also be reviewed for shunt informa�on.

Q11 Clin 0002 indicates to provide a ramp, sidewalk, and landscape, however that work appears to already be included in Clin 0001. It also states that clin 0002 represents an addi�on of 1228 sf to the building. We are not seeing an addi�on to the building in the contract documents. Can the scope of the 2 clins be clarified?

A11. Delete the ramp, sidewalk, and landscape from the CLIN 1 scope. The Addi�onal square footage of CLIN 2 represents an es�mate of ramp and sidewalk area that will increase the building’s overall footprint, not the building structure.

Q12 Do the liquidated damages on the project apply if delays are due to supply chain issues out of the control of the contractor?

A12. Typically speaking the General Contractor would need to substan�ate delays for Liquidated Damages to be excluded.

Q13 Sheet M701 indicates to provide RTU’s with 175 mbh capacity, and a 10:1 turndown. Specifica�on sec�on 237416.13 Large capacity packaged roo�ops sec�on 2.2 indicates to provide 600 mbh capacity, and sec�on 2.8 indicates a 30:1 turndown. Please advise of what capacity and turndown is required.

A13 Provide 175 mbh input/100 mbh output and minimum 10:1 turn down ra�o, as indicated on M-

701.

Q14 Specifica�on sec�on 237416.13 Large capacity packaged roo�ops – Is the intent for us to provide packaged RTU’s for this project, or custom air handlers? None of the major manufacturers have packaged units that meet all the criteria in the specifica�on. Packaged units are typical mass-produced units with op�ons most desired, and a custom air handler can be made to order, however the costs are drama�cally increased. Please advise of what unit was used as the basis of design that meets these requirements?

A14. The Bidder also asked for the Basis of Design, unfortunately we cannot do that (same rules as for Brand names). Therefore, the Intent is to provide packaged air handling units.

Q15: The response to RFI #4 (236423.13 Air cooled chillers, sec�on 2.1 B. indicates for zero percent performance tolerance. All manufacturers we have spoken with are excluding this requirement, and we are unaware of any that will meet it. Please advise of what unit was used as the basis of design that meets this requirement?

A15 236423.13, Sec�on 2.1B can be ignored. Comply with AHRI 550/950, per 236423.13, Sec�on 2.1C.

AHRI 550/590 Chapter 5 defines 2% as the upper limit for capacity tolerance of the chiller. Please also see Amendment 0004

Q16: The response to RFI #5 pertaining to integral pumps on the chiller (Specifica�on sec�on 236423.13

– 2.13 I) indicates to provide 2 pumps integral to the chiller, and 2 in the mechanical room. This will result in 4 pumps on the chilled water side of the unit, and cause restric�ons in the system. Addi�onally, the sequence of opera�on in the plans only addresses 2 pumps. If this is the intent, please provide a revised sequence of opera�on on how the 4 pumps are supposed to operate?

A16. There are no internal chiller pumps to be provided. Chiller pump informa�on can be ignored in specifica�on 236223.13. Please also see Amendment 0004