Z2DA--Replace Auxiliary Chiller

Replace Auxiliary Chiller Building 3

Project no: 565-24-113

Pre-Bid Questions

Does the Superintendent need to be directly employed by the Prime Contractor? Superintendent must be authorized to act in the name of the prime contractor.

Must the Superintendent be on site at all times while work is commencing? Yes

Does the SSHO (Site Safety Health Officer) need to be directly employed by the Prime Contractor? SSHO must be authorized to act in the name of the prime contractor.

Must the SSHO be on site at all times while work is commencing? Yes

Can the Superintendent & SSHO be a dual-hatted individual assuming that individual is qualified for both roles? Yes, see Spec 01 35 26.1.9 section heading: The Site Superintendent may also serve as SSHO if considered qualified by VA Engineering.

Are there any other mandatory on-site roles required in this contract? No

When does the VA expect the project to start following the award? The VA generally expects the project to start shortly after the award has been granted. The exact start date will be determined based on the completion of any necessary preparatory steps.

Are there any concerns for Asbestos Containing Material or Lead in the areas being worked in? There is no known ACM or lead as part of this project.

Are there any ICRA requirements for this project? Work will be completed inside a mechanical room and outside Building 3. Dust generation must be kept to a minimum. It is not anticipated that negative air, sticky mats, plastic barriers, or similar would be required.

Who is the current Controls provider at the VA? There is not one controls contractor. This is an open BACNET system as per the SOW.

Does the awarded contractor have to use this company's quote in our bid for controls integration? Not applicable

If yes, can the VA please provide contact info? Not applicable

Site Visit sign in sheet posted? See Attached Sign-In sheet

What manufacturer chiller is required to be replaced? None specified. Must meet Buy American and SOW requirements.

What is the physical size of the new chiller? If bigger than existing, does the VA want to increase the size of the concrete pad or provide steel framing? Contractor to utilize the current concrete pad. If contractor s proposed chiller exceeds the size and capacity of the current concrete pad, contractor will be responsible for any demolition and construction at no additional cost to the government. Contractor would have to first seek VA approval to exceed the current footprint as space is a premium.

Please confirm laydown and parking areas to be provided to contractor. Contractor may park in any available parking space at the facility. Laydown, if necessary, would be as directed by the COR. Assume the laydown area would be at the southeastern end of the facility, near the back gate.

Please confirm the VA will coordinate with awardee to only need 1 mobilization. Generally this job should only require 1 mobilization, assuming the VA will allow it. If the contractor mobilizes on site and the VA reschedules, this would be added cost. This question is unclear as to why multiple mobilizations are required. Contractor will provide the VA a proposed schedule and both parties will work towards those dates. Contractor will be responsible for submitting utility outage requests weeks before the desired date.

Scope states that the pumps be programed into the BAS Pumps can not be programed that have existing ( Old ) drives. Should drives be replaced. If so, are there specs? If pumps are independently controlled, then they should have new drives. Otherwise, new pumps to be controlled by the new chiller.

Chiller Specs ( equivalent vender ) design requirements ( Screw, Recep, modular ) ? Screw or scroll chiller is what should be submitted for approval. See Spec Section 23 64 00 Packaged Water Chillers

Chiller power scope is not clear; there are two existing circuits which to be used and what to be done on the second. Correct, there are two electrical circuits for the existing chiller. The VA expects the two circuits to be reused with the replacement chiller unless only one circuit is required. Contractor to ensure adequate amperage is available for their proposed chiller. If second circuit isn t required for new chiller, contractor to properly abandon circuit in place.

Will submittals be required on all products and approved? Yes.

Types of materials can fusion piping be used? No. Welded steel is appropriate. See specification section 23 21 13 Hydronic Piping.

No specs on Insulation or heat tape requirements. See specification section 23 07 11 attached.

Is there a road closure permit required for the site for purpose of the crane to be set up? See Spec Section 01 00 00.1.6.L&M. Contractor must minimize impact to the facility. Any potential, temporary road closures and crane lift plans would have to be approved by the VA engineering and safety.

Please provide provisions if existing isolation valves do not hold VA will assist contractor by providing information and assistance with coordination so to avoid or address this potential problem.

Controls scope states integration into BACNET card and into the BAS. Please clarify who has to be used for the integration and has access to program in system. Any certified controls contractor who is qualified to work on a Tridium DDC.

Existing Expansion tank Has it been verified to work and / or leave off scope? This is an expansion tank; estimated at 44 gallons. Contractor to verify this current tank volume is adequate for proposed new chiller.

Air separator to be vented external of building per A2L code requirements Not applicable.

No defined scope on pumps ( manufacture, base mounted as existing, how should they be built out { Tripple Duty valves, gauges and temps} Alignment? Lots to know on theses. See spec Section 23 21 23 Hydronic Pumps.

How many on site Pre Con meetings required? There will be one Pre Con meeting.

Scope doesn t state any required pre or post T&B - Please confirm if required. T&B not required. Contractor to verify flow is adequate across the primary chiller loop.

Is the intent for the new chiller to match the exciting modulating heat pump chiller? No.

Scope of Work

Replace Auxiliary Chiller at Building 3

Project Number: 565-24-113

Scope of Work

Location: 2300 Ramsey Street, Fayetteville, NC 28601, Located outside of Building 3

Scope:

Remove and replace the existing 120-ton auxiliary chiller at Building 3. The purpose of this chiller is to provide chilled water redundancy to Building 3. The new auxiliary chiller shall be the same size/capacity as the existing chiller and shall be fully functional.

The contractor shall replace and install all required piping, valves, supports, and controls. The new auxiliary chiller shall be integrated with the existing Building Automation System (BAS). Chiller controller shall be BACNET compliant, and all data points should be pulled through the BACNET connection. The contractor shall install minimum (hard wired) data points to include but not limited to (1) Start/Stop, (2) Status, and (3) Alarm (hard wired). All low voltage control wirings must be installed in blue control conduit. All graphics/trends and digital alarming associated with the new chiller must be updated on the Tridium Direct Digital Control (DDC) Supervisor located in Room 2 in Building no. 35.

The contractor shall replace two (2) 250 gpm pumps located in an adjacent mechanical room; shown on Sheet M103 as B-20A. Contractor may reuse the existing concrete pads. Replace/reroute piping, if required, to install the new pumps. Pumps shall be programmed into the BAS with the same data points as the chiller.

*Note that the existing auxiliary chiller has two electrical circuits.

Contractors are strongly encouraged to attend the pre-bid site visit. The date is to be determined.

Requirements:

All work shall be performed in full accordance with applicable local and Federal regulations. All equipment and installation shall conform to the VA master specifications, recommendations of the National Fire Protection Association (NFPA), and Underwriters Laboratories, Inc. The contractor shall use good safety practices during demolition and installation.

The contractor shall conduct a pre-installation site visit to verify field conditions.

The contractor shall attend a pre-construction meeting with VA stakeholders

The contractor shall perform testing and demonstrate proper operations of new chiller with VA maintenance.

The contractor shall submit the following to the VA upon completion:

Operation & Maintenance manuals

Warranty documentation

Storage: No storage of any material will be allowed on VA property.

Period of Performance: To be completed within 6 months of NTP. This should allow adequate time for product lead times.

Hours of Operation: Normal working hours: 0800-1700, M-F. Evening and weekend work may be approved by COR.

Utility and System or Service Outages: No utility services such as water, gas, steam sewers or electricity, parking, or fire protection systems and communications systems may be interrupted without prior approval of COR. Electrical work shall be accomplished with all affected circuits or equipment de-energized in accordance with VA Lock-out Tag-out requirements. The contractor shall submit a request to interrupt any such services to COR, in writing, 28 days in advance of the proposed interruption.

Attachments:

Attachment 1-M103 AHU 30 Bldg. 3 Mech Room 20 Chilled Water 2014 drawing from a 2014 construction project

Photo 1-Existing Airstack Chiller at Bldg. 3

Photo 2-Data Plate west Airstack existing chiller data plate

Specs AuxChillBldg3

END SCOPE OF WORK