QA 1 8 July - Repair AHUs.docx

Repair AHUs

FA875120B0002

Q&A – 8 July 2020

Q1. If work is to be performed in the evenings and on weekends- the areas affected by the individual air handlers would only be allowed to be taken out of service and needed to be put back in operation by the following Monday. Please confirm.

A1. Yes, the HVAC system must be put back into normal operating condition prior to the start of normal operating hours.

Q2. Will the areas of work below the specified work zones have the employees moved to other areas during the work?

A2. No they will not unless there is a safety concern that requires the areas to be vacated.

Q3. Should the specifications for Automatic Temperature Control be the same for FA875120B0002 and FA875120B0005?

A3. Both specifications are different and correct from AFRL point of view.

Q4. Are the current wiring and devices inoperable, or in need of upgrade?

A4. The project should be bid as drawn and specified, which states to replace all control devices and wiring.

Q5. Are there any pneumatic devices that would need to be retrofitted to electronic?

A5. There are no pneumatic devices involved with this project.

Q6. Drawing number 10 AHU ACU-E1 does not indicate replacement of access doors similar to the other air handlers. The new fans will not fit through the existing doors. Please clarify.

A6. Please include the replacement of access doors.

Q7. General note B directs the contractor to remove and replace all fabric covered insulation. Please confirm.

A7. Bid the replacement canvas jacketing as it is shown on the documents.

Q8. Contractor would like clarification if preparation work such as moving in materials, such as duct, insulation, fans, and electrical work can be accomplished during normal working hours and only perform the ductwork modification and fan change out during the weekends?

A8. The specifications state work shall be done on the weekends. The intent is to ensure existing systems are operable during normal duty hours. Weeknight work can possibly be included in the same manner as the weekend hours if it meets the criteria described previously, but will need to be approved at the discretion of the Government.

Q9. Several variable speed drives will be required to be temporarily moved out of the way to accommodate the fan installation. Large sections on the air handler have to be opened up to extract and install the new fans.

A9. The new access doors will provide the opening required for handling the fans.

Q10. Ductwork insulation notes on the plans rigid board insulation not canvas covered insulation or blanket type insulation.

A10. All ductwork in the penthouse/monitor area is to be considered exposed and in an equipment room. Please provide insulation per the schedule.

Q11. Please specify insulation thickness.

A11. See Sheet 40, “Insulation Schedule”, last line “F”, last row, “Ductwork, E” notes thickness for interior concealed and exposed.