548-23-122 QAs.pdf

RFI Q&A for Phase 1 36C24823R0051 Install Additional Pump on OR Chilled Water Loop

1. Solicitation states The power feed to the two (2) existing pumps will be rewired by the contractor so that the pumps are not on the same electrical panel. Question will each pump (3 total) be connected to their own individual panel and if so is there available space in existing panels without added modifications?

a. Each pump is run from its own VFD. Those VFD’s are fed from different Power Panels in the second‐ floor mechanical room. There is additional power available from one of those 2 panels for the 3rd pump.

Install manual VFD bypass starter with double‐throw switch for all VFDs? In the event of a VFD failure pumps shall be able to operate at a constant speed. VFD integration shall be Hard Wired: VFD Status, Enable/Disable, Modulation ; BACNet: Alarm, Freq, Power, Energy, Oper Hrs, Motor Current, Voltage.

2. Will a flow test be required prior to start or at finish of project.

a. If the contractor has a need to do a flow test for his design or warrantee of his work, that will be up to the contractor. Testing of entire system will be after construction has been completed.

3. Reference specification section 01 00 00‐1.3, statement of Bid. The reference specification notes the installation and delivery of a complete wander management system. Please confirm that this section should note “Install Additional Pump on OR Chiller Loop”.

a. Yes, you are correct, it should read Install Additional Pump on OR Chiller Loop

4. Reference specification section 01 00 00‐1.5.C, unarmed guards. Please clarify if unarmed guards are required for this project?

a. Not necessary

5. Reference specification section 01 00 00‐1.30, photographic documentation. Please clarify if the phot indexing and navigation documents are required for this project. We would recommend that the VA change this to note that the contractor shall provide monthly photos with a description of the work noted in the photos.

a. The VA is good with this and will note that the contractor shall provide monthly photos with a description of the work noted in the photos

6. Reference specification section 01 00 00‐1.31, final elevation images. Please clarify if this project will require final elevation photos as noted in the reference section.

a. Elevation sections are not necessary

7. Reference specification section 00 11 21. The reference section notes 10 hard copies, and, in another paragraph, it notes 20. For a project, this size we would recommend 3 hard copies with 1 full size set and 2 half size sets. Please clarify the number of copies required for the plans and specs for each submission.

a. 3 hard copies with 1 full size set and 2 half size sets shall be required for the plans and specs for each submission.

8. Reference section A.3, Price/Cost Schedule, Item 0001. The referenced section notes a period of performance as 120 days after notice to proceed (NTP). With two design developments and submission of the final 100% for construction documents and the current market conditions for ordering frequency drives and pumps we would recommend the VA increase the period of performance to a minimum of 365 days. Please clarify the period of performance for this project.

a. Since the project is something we want to move as quickly as possible The VA would agree to 180 days for the performance period after NTP. If there are logistics issues they can be brought up after award and prior to NTP.

9. Reference project summary in the Price/Cost Schedule and in the Project Summary Section. The referenced project summary notes that the existing pumps and the new pump (added) shall be on different electrical panels. We have outlined a couple recommendations below in Item #8. We would recommend that the air‐cooled chillers and pumps be on the critical equipment branch based on the critical areas served by this system. We would recommend the added pump be added to one of the existing substations (normal power) until the critical power distribution switchboard is upgraded to support adding the additional load to the critical equipment branch. Please advise if this is acceptable.

a. Each pump is run from its own VFD. Those VFD’s are fed from different Power Panels in the second‐ floor mechanical room. There is additional power available from one of those 2 panels for the 3rd pump.

10. The period of performance is noted as 120 days after NTP. The design development for three submissions will be approximately 50% of the performance period. In today’s market it will be very difficult to complete the design and construction for this project 120 calendar days. We would recommend a minimum of 365 days for this project. Please clarify the period of performance for this project.

a. Since the project is something we want to move as quickly as possible The VA would agree to 180 days for the performance period after NTP. If there are logistics issues they can be brought up after award and prior to NTP.

11. Please clarify if a superintendent can be a dual hat to cover the requirements of SSHO?

a. Dual Hat is fine as long as the certifications are current and met.

12. If no to the question above, will the SSHO need to be full‐time for this project?

a. Your own safety program should detail this

13. Project Experience is requested during Phase I. Will the government confirm Past Performance will be provided in Phase II and not during Phase I along with Project Experience.

a. It will be evaluated for both

14. Our team has reviewed the scope of work for this project, and we would like to provide some general recommendations to the VA on the noted scope to assist the VA on the current issues we have noted with the current system. We understand that the current scope involves adding an additional chilled water pump, frequency drive for the added pump, and the required controls to interface the OR Chillers System into the existing Siemens’ Building Automation System so that it is a totally integrated system. We also understand that both the Phase I and Phase II submission requirements do not require a technical narrative which fully describes our design approach for the project. Therefore, we would like to address these issues at this time so the VA can analyze the issues we’ve noted and if necessary, the VA can modify the project’s scope to resolve the issues we have noted. Below is a summary on the issues we have noted with the current OR Chiller System as installed.

New air‐cooled chillers 1‐ACCH3 & 1‐ACCH4 are currently fed from Substation C and Substation H (normal power). Chillers ACCH‐1 & ACCH‐2 are currently feed off ATS‐11 (critical equipment branch – emergency power). The current controls have a defined staging sequence for each chiller. Our concern is related to what happens when there is a power outage, or the VA is testing the emergency generators.

When the chillers experience a loss of power there is a time delay that is energized in the chiller control panels that allows the refrigerant circuits to equalize the pressures before the chiller controls will re‐ start. This can run between 15‐25 minutes. When a power outage takes place the associated air handling units which are served from the air‐cooled chillers should be shut down and the auto re‐start should be either disabled or additional controls added to coordinate the re‐start of the associated air handling units after the chiller water temperature in the chiller loop is satisfied.

Recommendation(s):

(1) Add additional controls to the OR Chiller System and Associated AHU’s along with modifying the sequence of operation for the OR Chillers and Associated Air Handling units to ensure the chilled water temperature has returned to set point temperature prior to re‐starting the associated air handling units.

(2) Recommend the VA add scope that the new air‐cooled chillers (1‐ACCH3 & 1‐ACCH4) are connected to the critical equipment branch once the current emergency power distribution system has the capacity to support the added chillers. This recommendation has a major cost impact and should be addressed under a separate project to upgrade the emergency power distribution switchboard, feeders, and ATS to feed the four (4) air cooled chillers and the chilled water pumps (existing and new).

Please see below RFIs noted in our initial review of the RFP:

a. Some of these concerns may go away by the time this project takes place. They will not be included in this project

For all drawings and submittals the following applies:

Existing as‐built drawings will be provided to the A/E (as required), however, no guarantee is made as to the accuracy of these plans. All features and conditions indicated therein must be verified by the A/E as inclusive of the scope of the design services they provide. The A/E shall perform all necessary site surveys to verify conditions in the field to confirm the accuracy of the as‐built plans provided.

Attachments are provided in support of the following requests:

1. Please provide an as‐built/record drawings for the OR chiller project that added the third chiller and the Eaton Drives for the new pumps.

2. Please provide the as‐built/record drawings for the power distribution currently installed that feeds the OR chillers and the Chilled Water Pumps.

3. Please provide the submittals for the following: (a) Air cooled OR chillers, (b) OR chiller pumps, (c) Eaton Variable Speed Drives, and (d) controls currently installed for the OR chiller system.

4. Please provide the piping schematic for the OR Chillers and how it is tied into the main chilled water loop for the medical center.

5. Please provide the current sequence of operation for the OR Chillers.

6. Please provide architectural as‐builts for the space if available.

7. Please provide electrical as‐builts for the space if available.

8. Please provide mechanical piping as‐builts for the space if available.

9. Please provide the submittals for the chiller project (548‐18‐116, contract #36C24818D116) for the existing chiller pumps, Eaton VFD, and the existing Control Package.