Air Cooled Chiller Replacement - SOW - NC0058ZZ - Revised 5262020.pdf

U.S. General Services Administration

Public Buildings Service Greater Southeast Region

Date: 05/26/2020

Scope of Work

1. Project Title: Replace Air Cooled Chiller

2. Project Location: Century Station Federal Courthouse, 300 Fayetteville St, Raleigh, NC

27601

3. Building Location Hours: 7:00 am – 5:30 pm

4. Purpose: The existing chiller has exceeded the industry standard for service life of a chiller and is well pass the mandated timetable for replacing R22 system. Further, the chiller can no longer delivers the savings outlined in the GSA Energy conservation Standards. The intent of this project is to replace the unreliable the existing R22 Air Cooled Chiller adjacent to the listed property in the parking lot of the building with a modern version new one of the same capacity.

5. Points of Contact:

5.1 Contracting Officer: TBD

5.2 Project Manager: TBD

5.3 Building Manager: Jeannie Speckman

310 New Bern Avenue, Room 178 Raleigh, NC 27601

(O) 919-856-4681

(C) 919-264-3774

5.4 BSS/COR: Duane Jones (BSS)

310 New Bern Avenue, Room 178 Raleigh, NC 27601

(C) 919-561-2349

6. Notice to Proceed:

6.1 The Contracting Officer is the ONLY individual from the Government that can give the contractor a notice to proceed.

6.2 Before any of the work within the scope of the contract is started, the Contractor shall confer with the COR (Contracting Officer Representative) and agree on a sequence of procedure; means of access to premises and building; delivery of material and use of approaches; use of corridors, stairways, elevators, and similar means of communications; and the location partitions, eating spaces for spaces for Contractor’s employees and the like.

7. Period of Performance: [The period of performance for this contract task order will not exceed ninety (90) days from the date of the contractor notice to proceed (NTP).

7.1 Kick off meeting: T.B.D.

7.2 Contractor Notice to Proceed: T.B.D.

8. Description of Work: Contractor shall provide all materials, labor, tools, equipment and supervision to accomplish tasks as outlined.

9. General: Factory-assembled and-tested rotary-screw or scroll water chillers, complete with evaporator, compressors, motor, integral condenser, and controls mounted on a welded steel base. The chiller unit shall consist of two compressors minimum, but not more than four , mounted on a single welded steel base. Where compressors are paralleled, not more than two shall be so connected and not less than two independent refrigerant circuits shall be provided. Chiller shall be capable of operating one of the following refrigerants: HCFC- 134a or HCFC-410a.

10. Performance: Chiller shall provide the capacity of 60 Ton of cooling. Part load and full load efficiency ratings of the chiller shall meet the new efficiency levels mandated by ASHRAE Standard 90.1.

10.1 Leaving water temperature solution range shall be 42 to 65°F(5.5 to18°C)

10.2 Supply water temperature drop shall be based on a drop of 10°F (6°C) for I-P data

10.3 Chiller shall be furnished with a precise capacity control that shall ensure chilled water temperatures are maintained +/- 1/2°F (0.28°C) of setpoint

11. Applicable Standard: Chillers shall be rated and certified according to AHRI 550/590, and shall be stamped in compliance with AHRI certification.

12. Compressor (Rotary-Screw Type): Positive-displacement oil injected type, direct drive, cast-iron casing, precision-machined for minimum clearance about periphery of rotors.

Lubrication system shall provide oil at proper temperature to all moving parts. Capacity control shall be by means of single slide valve to modulate the capacity from 100 to 30 percent of full unit rated capacity and hot gas bypass without unstable compressor operation. The slide valve shall be hydraulically operated upon the actuation of temperature or pressure sensor.

13. Compressor (Scroll Type): Three dimensional, positive-displacement, hermetically sealed design, with suction and discharge valves, crankcase oil heater and suction strainer.

Compressor shall be mounted on vibration isolators. Rotating parts shall be factory balanced. Lubrication system shall consist of reversible, positive displacement pump, strainer, oil level sight glass, and oil charging valve. Capacity control shall be by on-off compressor cycling of single and multiple compressors.

14. Refrigerants Circuit: Each circuit shall contain or include an electronic expansion valve, refrigerant charging connections, hot-gas muffler, compressor suction and discharge shutoff valves, replaceable-core filter drier, sight glass with moisture indicator, liquid-line solenoid valve and insulated suction line.

15. Refrigerant and Oil: Sufficient volume of dehydrated refrigerant and lubricating oil shall be provided to permit maximum unit capacity operation before and during tests. Replace refrigerant charge lost during the warranty period, due to equipment failure, without cost to the Government.

16. Condenser: Air-cooled integral condenser specified hereinafter.

16.1 Integral Condenser: Condenser coils shall be extended surface fin and tube type, seamless copper tubes with corrosion coated aluminum fins .

16.2 Condenser coils shall be factory air tested at 3105 kPa (450 psig).

16.3 Condenser fans shall be propeller type, directly connected to motor shaft. Fans shall be statically and dynamically balanced, with wire safety guards. Condenser fan motors with permanently lubricated ball bearings and three phase thermal overload protection.

16.4 Units shall have grilles factory mounted to prevent damage to coil surfaces.

17. Evaporator: Shell and tube design with seamless copper tubes roller expanded into tube sheets. Designed, tested, and stamped in accordance with applicable portions of ASME Boiler and Pressure Vessel Code, Section VIII, for working pressure produced by the water system, but not less than 1035 kPa (15 psig). Refrigerant side working pressure shall comply with ASHRAE Standard 15. Shell shall be constructed of carbon steel. For the waterside of liquid cooler the performance shall be based on a water velocity not less than 1 m/s (3 fps) with a maximum water velocity of 3 m/s (10 fps) and a fouling factor

0.0000176 m2 degrees C (0.0001 hr. sq. ft.) degrees F/Btu Evaporator shall be protected against freeze-up in ambient temperature down to -20°F (-30°C) by a resistance heater cable under insulation with thermostat set to operate below 37°F (3°C) ambient.

18. Insulation: Evaporator, suction piping, compressor, and all other parts subject to condensation shall be insulated with 20 mm (0.75 inch) minimum thickness of flexible-elastomeric thermal insulation, complying with ASTM C534.

19. Refrigerant Receiver: Provide a liquid receiver for chiller units when system refrigerant charge exceeds 80 percent of condenser refrigerant volume. Liquid receivers shall be horizontal type, designed, fitted, and rated in conformance with AHRI 495. Receiver shall be constructed and tested in conformance with Section VIII D1 of the ASME Boiler and Pressure Vessel Code. Each receiver shall have a storage capacity not less than 20 percent in excess of that required for fully charged system. Each receiver shall be equipped with inlet, outlet drop pipes, drain plug, purging valve, and relief devices as required by ASHRAE Standard 15.

20. Controls: Chiller shall be furnished with unit mounted, stand-alone, microprocessor-based controls in NEMA 4 enclosure, hinged and lockable, factory wired with a single point power connection and separate control circuit. The control panel provide chiller operation, including monitoring of sensors and actuators, and shall be furnished with light emitting diodes or liquid-crystal display keypad.

20.1 Control shall be easy-to-use operator interface with diagnostics information

21. Following shall display as a minimum on the panel:

21.1 a. Date and time.

21.2 b. Outdoor air temperature.

21.3 c. Operating and alarm status.

21.4 d. Entering and leaving water temperature-chilled water.

21.5 e. Operating set points-temperature and pressure.

21.6 f. Refrigerant temperature and pressure.

21.7 g. Operating hours.

21.8 h. Number of starts.

21.9 i. Current limit set point.

21.10 j. Maximum motor amperage (percent).

22. Control Functions:

22.1 a. Manual or automatic startup and shutdown time schedule.

22.2 b. Entering and leaving chilled water temperature and control set points.

22.3 c. Automatic lead-lag switch.

23. Safety Functions: Following conditions shall shut down the chiller and require manual reset to start:

23.1 a. Loss of chilled water flow.

23.2 b. Low chilled water temperature.

23.3 d. Compressor motor current-overload protection.

23.4 e. Freeze protection.

23.5 f. Starter fault.

23.6 g. High or low oil pressure.

23.7 h. Recycling pump down.

24. The chiller control panel shall provide leaving chilled water temperature reset based on outdoor air temperature.

25. Provide contacts for remote start/stop, alarm for abnormal operation or shutdown, and for Building Automation System.

26. Chiller control shall be scalable and easily integrate with GSA’s BAS via BACnet® or

LonTalk® communication interfaces.

27. Auxiliary hydronic system and the chiller shall be interlocked to provide time delay and start sequencing. Chiller will be required to start the pumps through a dry set of contacts.

28. Servicing: Chiller shall be oriented to ensure adequate clearance for servicing the evaporator and compressor(s). Also, clearance shall be provided to allow for control panel door swing and routine maintenance requirements.

29. Contractor shall perform all work to all local, state, National, Manufacturers, Industry, and

P-100 standards. Some of the standards include but are not limited to

a. AHRI Standards

b. ASHRAE Standards

c. NEMA / NEC Standards

d. ASTM Standards

e. OSHA Standards

f. ASME Standards

30. Existing Chiller

31.1 Contractor shall remove all field connections to the existing chiller including but not limited to

30.1.1 Electrical connections (High and control voltage). Contractor is to save as much of the control wiring, and high voltage wiring as possible for use in the installation of the new chiller.

30.1.2 Piping (as needed for installation of new Chiller) and any associated gauges, thermometers, insulation, etc. as necessary.

30.2 Disposal

30.2.1 Contractor shall dispose of and recycle the old chiller and provide documentation showing the recycling and disposal of the old chiller.

Contractor shall dispose of any materials deemed as trash

31. Replacement Chiller

31.1.1 Contractor shall provide submittals for three types of chillers based upon the requirements above for GSA review. Upon selection of chiller by GSA, the contractor shall provide the approved chiller.

32. Installation of replacement chiller

32.1.1 Electrical (High Voltage)

32.1.1.1 Contractor shall provide any necessary materials of high quality and NEMA/NEC rating needed for the complete installation of the high voltage, Contractor shall ensure that proper breaker sizes, fuses and wiring are up to code. The contractor shall make all connections at the chiller based upon the manufacturer’s recommendations.

Contractor shall ensure all connections are tight and compatible with the existing electrical system. All work to be performed to local, state, national, P-100, NEC, and manufacturer codes and standards.

32.1.2 Electrical (Control Voltage)

32.1.2.1 Contractor shall provide any necessary materials of high quality and NEMA/NEC rating needed for the complete installation of the control voltage. Contractor shall install based upon previous requirements in the scope and will make all connections per manufacturer’s specifications. The contractor shall ensure that all connections are tight and compatible with the existing control system.

All work to be performed to local, state, national, P-100, NEC, and manufacturer codes and standards.

32.1.3 Piping (Chilled Water)

32.1.3.1 Contractor shall provide any necessary materials including but not limited to piping, valves, gauges, thermometers, welding materials, and insulation. Contractor shall ensure that new chiller is compatible with the existing piping and pumps. Contractor shall add piping, and fittings as necessary to make the connections to the existing piping system, and the chiller. Contractor shall make the connections to the chiller using manufacturer and industry recommended fittings. Contractor shall check water flow rate before and after chiller replacement and balance in accordance with chiller specs, and industry standards.

32.1.3.1.1 Contractor shall install a new flow switch. Contractor shall provide wiring to flow switch, and land connections at the flow switch and chiller. Contractor shall provide a submittal for the flow switch.

32.1.3.1.2 Contractor shall install two isolation valves. One shall be installed on the Chilled Water Supply. One shall be installed on the Chilled Water Return.

32.1.3.1.3 Contractor shall install new brass backed liquid filled water pressure gauges. One gauge will be in the chilled water supply and one will be in the chilled water return.

32.1.3.1.4 Contractor shall install gauge attachments

a.Snubbers: ASME B40.100, brass; with ¼” NPT, ASME B1.20.1 pipe threads and porous-stainless steel filter-type surge-dampening device. Include extension for use on insulated piping.

b.Siphons: Loop-shaped section of brass (for normal operating pressure/temperature up to 200 psi, 325 F) or stainless-steel (for normal operating pressure/temperature greater than for brass) pipe with ¼” NPT pipe threads.

c.Valves: Brass body, stainless ball, selected for working pressure suitable for application, with ¼” NPT, ASME B1.20.1 pipe threads.

32.1.3.1.5 Contractor to install new thermometers. The contractor shall provide a submittal for the new thermostats. One is to be installed in the Chilled Water Supply utilizing the existing well if possible. One is to be installed in the Chilled Water

Return utilizing the existing well if possible. If existing wells cannot be used or are not existent, then the contractor shall provide new wells, and install wells into the chilled water piping.

32.1.3.1.6 Contractor shall install a new heat tape system on the new sections of pipe. Contractor shall provide operating scheme for heat tape. Contractor shall provide and install power supply and thermostat for heat tape. Contractor shall provide a submittal for the heat tape.

32.2 Start Up

32.2.1 Pre Start Up Inspection

32.2.1.1 A prestart up inspection will be performed ensuring that all connections are tight and wires are landed properly. A check to ensure that there are no leaks in the refrigeration system is necessary.

32.2.1.1.1 If there are any leaks then they need to be found and repaired. A triple evacuation procedure of the refrigerant system must be performed and filter cores, liquid line driers, etc.(If applicable) must be changed.

32.2.2 Start up

32.2.2.1 Upon a successful inspection a full start up procedure shall be performed to manufacturer’s specifications. Records of all pertinent data must be submitted to both the GSA project manager and the onsite O&M staff for proper records keeping. Examples include but are not limited to

32.2.2.1.1 Load conditions

32.2.2.1.2 Outdoor Ambient Conditions

32.2.2.1.3 Water pressure readings

32.2.2.1.4 Amperage readings

32.2.2.1.5 Approach temperatures

32.2.2.1.6 Flow rates

32.2.2.1.7 Etc.

32.2.2.2 Contractor shall ensure proper operation according to manufacturer’s specifications and all applicable codes and standards described in this scope.

32.2.2.3 All data shall be recorded and a copy shall be provided to the O&M for storage on site, and to the GSA project manager

32.2.3 Post Start Up

32.2.3.1 Contractor shall provide all documentation to the O&M contractor for storage in the maintenance office on site and GSA project manager

32.2.3.2 Contractor shall provide a half hour training session for the O&M contractor and GSA on the operation and specifics of the unit

32.2.3.3 Contractor shall provide any warranty’s with unit i.e.

manufacturer, labor, contractor, etc.

32.2.3.4 Contractor shall perform terminal clean up and provide GSA with any waste manifests

32.2.4. Optional Piping

32.2.4.1 Relocate existing 6" cooling tower condensing supply water line to allow a 4' side clearance from the air cooled condenser. Pipe shall be insulated to match existing insulation. Contractor shall make the connections to the tower using manufacturer and industry recommended fittings.

32.2.4.2 Relocate existing 3/4" cooling tower make-up water line to allow a 4' side clearance from the air cooled condenser. Pipe shall be insulated to match existing insulation. Contractor shall install a new solenoid valve within 1' of cooling tower. Contractor shall install a new heat tape system on the new sections of pipe. Contractor shall provide operating scheme for heat tape. Contractor shall provide and install power supply and thermostat for heat tape. Contractor shall provide a submittal for the heat tape.

33. Liquidated Damages If cost of project is above $35K:

33.1 Per day: $110 dollars per day

34. Other Requirements:

34.1 Security: Security clearance requirements are in effect.

34.1.1 All contractors need to be HSPD-12 cleared or escorted by HSPD-12 cleared personnel

34.1.2 All contractors are subject to being screened upon entry into the building

34.2 Waste Diversion

34.2.1 Waste removal is a daily responsibility of the contractor.

34.2.2 Daily clean-up is a requirement.

34.2.3 A thorough final space cleaning, to include all surfaces, light fixtures, etc.

must be performed by the contractor prior to final job acceptance walk-through.

34.2.4 All care must be given to protecting furnishings, flooring, walls, and all other items within the space while work is being performed. Use of appropriate dust / debris control methods is necessary

35. Submittal: [Product specific submittals must be presented and approved on the following products before ordering:]

35.1 Waste Diversion sheet will be required upon project close out

35.2 Letter from contractor stating that no products known to contain asbestos were used in this project

35.3 Release of claims will be required upon project closeout

35.4 Submittal for new chiller

35.5 Submittal for thermometers

35.6 Submittal for Liquid Filled Pressure Gauges

35.7 Submittal for any electrical enclosures that need to be installed

35.8 Submittal of Factory completed start up data

35.9 Submittal for proof of training

35.10 Submittal for Heat Tape, and controls

35.11 Submittal for warranty information

36. Attachments: [The following items will become part of the Scope of Work.]

37. Closeout Plan: [Upon final completion of the project, the contractor will notify the GSA Project Transaction Manager to schedule a final project walk-through for the purpose of:.]

37.1 Customer Acceptance

37.2 Final Punch list complete

37.3 Financial Closeout

Reviewer Signature:____________________ Date:_______