Amendment_0003.pdf

Offers must acknowledge receipt of this amendment prior to the hour and date specified in the solicitation or as amended, by one of the following methods:

(a) By completing items 8 and 15, and returning or (c) By separate letter or telegram which includes a reference to the solicitation and amendment numbers. FAILURE OF YOUR ACKNOWLEDGMENT TO BE RECEIVED AT THE PLACE DESIGNATED FOR THE RECEIPT OF OFFERS PRIOR TO THE HOUR AND DATE SPECIFIED MAY RESULT IN REJECTION OF YOUR OFFER. If by virtue of this amendment your desire to change an offer already submitted, such change may be made by telegram or letter, provided each telegram or letter makes reference to the solicitation and this amendment, and is received prior to the opening hour and date specified.

E. IMPORTANT: Contractor is not, is required to sign this document and return copies to the issuing office.

AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT 1. CONTRACT ID CODE

2. AMENDMENT/MODIFICATION NO. 3. EFFECTIVE DATE 4. REQUISITION/PURCHASE REQ. NO. 5. PROJECT NO. (If applicable)

7. ADMINISTERED BY (If other than Item 6) CODE

STANDARD FORM 30 (REV. 10-83)

Prescribed by GSA FAR (48 CFR) 53.243

FACILITY CODE

9A. AMENDMENT OF SOLICITATION

NO.

9B. DATED (SEE ITEM 11)

10A. MODIFICATION OF CONTRACT/ORDER NO.

10B. DATED (SEE ITEM 13)

11. THIS ITEM ONLY APPLIES TO AMENDMENTS OF SOLICITATIONS

The above numbered solicitation is amended as set forth in Item 14. The hour and date specified for receipt of Offers is extended, is not extended.

12. ACCOUNTING AND APPROPRIATION DATA (If required) copies of the amendment; (b) By acknowledging receipt of this amendment on each copy of the offer submitted;

13. THIS ITEM ONLY APPLIES TO MODIFICATION OF CONTRACTS/ORDERS.

IT MODIFIES THE CONTRACT/ORDER NO. AS DESCRIBED IN ITEM 14.

CHECK ONE A. THIS CHANGE ORDER IS ISSUED PURSUANT TO: (Specify authority) THE CHANGES SET FORTH IN ITEM 14 ARE MADE IN THE CONTRACT ORDER NO.

IN ITEM 10A.

B. THE ABOVE NUMBERED CONTRACT/ORDER IS MODIFIED TO REFLECT THE ADMINISTRATIVE CHANGES (such as changes in paying office, appropriation date, etc.) SET FORTH IN ITEM 14, PURSUANT TO THE AUTHORITY OF FAR 43.103(b).

C. THIS SUPPLEMENTAL AGREEMENT IS ENTERED INTO PURSUANT TO AUTHORITY OF:

D. OTHER (Specify type of modification and authority)

Except as provided herein, all terms and conditions of the document referenced in Item 9A or 10A, as heretofore changed, remains unchanged and in full force and effect.

15C. DATE SIGNED

15A. NAME AND TITLE OF SIGNER (Type or print)

16C. DATE SIGNED

16A. NAME AND TITLE OF CONTRACTING OFFICER (Type or print)

14. DESCRIPTION OF AMENDMENT/MODIFICATION (Organized by UCF section headings, including solicitation/contract subject matter where feasible.)

PAGE OF PAGES

6. ISSUED BY CODE

8. NAME AND ADDRESS OF CONTRACTOR (No., street, county, State and ZIP Code) (X)

CODE

15B. CONTRACTOR/OFFEROR

(Signature of person authorized to sign)

16B. UNITED STATES OF AMERICA

(Signature of Contracting Officer)

NSN 7540-01-152-8070

Previous edition unusable

7PQD

Shawna Villarreal, Contracting Officer

See attached.

7PQD

ACQUISITION MANAGEMENT DIVISION

ACQUISITION ENERGY & ACQUISITION SUPPORT

BRANCH

819 TAYLOR ST RM 12B01

FORT WORTH TX 6102

ACQUISITION MANAGEMENT DIVISION

ACQUISITION ENERGY & ACQUISITION SUPPORT

BRANCH

819 TAYLOR ST RM 12B01

FORT WORTH TX 6102

EQ7PMD-17-0015

GS-07-P-17-HT-C-0004

1 2

4/14/2017

4/5/2017

Amendment No. 3 – Solicitation No. GS-07-P-17-HT-C-0004 Chiller Removal & Installation at the Federal Building in Little Rock, AR

This amendment is issued to respond to questions.

1. Can you please provide justification for not allowing the single compressor chiller?

RFI

Would a magnetic bearing centrifugal chiller that utilizes a single compressor be an acceptable product for this bid/replacement? The chiller has better part load efficiency than the project requirements and meets the stipulated water pressure drop. The chiller uses R-134a refrigerant and has local factory service within 15 miles of the jobsite.

Supporting information for the request A multiple compressor chiller is designed as such because the OEM manufacturer for the compressors has a limit of 400 or 600 tons as the maximum compressor size. The perceived benefits of having a multiple compressor chiller are better part load efficiency, lower minimum turndown capacity, and redundancy. All of these would be true benefits to the owner but should be looked at more carefully to understand the actual capabilities of the available chiller offerings:

· Multiple compressors have the ability to turn a compressor off at low loads and can realize an efficiency improvement. This greater magnitude will be evident in the part load efficiency rating. The available part load efficiency of a single compressor chiller that bears AHRI rating for independently certified performance is better than the SOW efficiency requirement. There is no greater benefit to a multiple compressor chiller in available efficiency.

· The single compressor chiller has the ability to turndown to 10% capacity at constant entering condenser water temperature without the use of hot gas bypass. Because this is an industry standard, there is no greater benefit to a multiple compressor chiller in available capacity turndown.

· Having multiple compressors would provide redundancy if each compressor were on an independent refrigerant and electrical circuit. Since both compressors are manifolded to a common evaporator and condenser, when one compressor, integral VFD, or integral controller fails, the entire machine will have to be offline to repair. Furthermore, the study of statistics tells us that the more components are installed in a system that it will increase the probability of failure. There is no greater benefit for having multiple compressors because redundancy is compromised when the compressors are on a common circuit and reliability is diminished because there is statistically an increased probability of failure.

At least 2 compressors on this size chiller will provide us with redundancy we need for this particular chiller plant. Our specification does not require single electrical or refrigerant circuits nor does it prohibit the use of multiple electrical or refrigerant circuits. Multiple or single electrical and refrigerant circuits are allowable on chillers with two or more compressors.