SOW Replace Trane 230 Ton Chiller_DRAFT.pdf

Agricultural Research Service

U.S. DEPARTMENT OF AGRICULTURE

Last Updated 2/11/2025

STATEMENT OF WORK

Replace Trane RTAF-230 Ton Chiller

Southeast Area Thad Cochran Southern Horticulture Lab

810 Hwy 26W Poplarville, MS 39470

Asset ID: 640400B38

DRAFT C

OPY

Poplarville, MS – Replace 230 ton Trane Chiller Page 2 of 16

1. PROJECT INTRODUCTION

1.1. PROJECT TITLE

Replace Trane RTAF-230 Ton Chiller.

1.2. PROJECT BACKGROUND AND PURPOSE

1.2.1. The USDA ARS Thad Cochran Southern Horticulture Laboratory is located at

810 Hwy 26W, Poplarville, MS 39470. The main building at this Location (building 38) houses most of the administrative activities as well as some laboratory space. The building was completed in 2005. The HVAC system for Building 38 was designed to utilize a matched pair of 230 ton chillers (Chillers #1 & #2). The original pair of chillers were Trane model RTAF 230 ton and were originally commissioned in 2005.

1.2.2. In 2024, Chiller #1 failed and was replaced with the newest model Trane RTAF 230 ton chiller. This new chiller was installed and commissioned in October 2024. Like chiller #1 before replacement, the remaining chiller (chiller #2) is beyond its expected service life, no longer under warranty, and is not capable of cooling the building in its current state and is in need of replacement.

1.3. PROJECT CONTACT PERSONS

CONTRACTING OFFICER (CO)

XXX, Contract Specialist USDA, ARS, ARM, Southeast Area xxx-xxx-xxxx XXX@usda.gov

ADMINISTRATIVE OFFICER (AO)

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LOCAL POINT OF CONTACT (LPOC)

2. SCOPE AND OBJECTIVES

2.1. DESCRIPTION OF WORK

2.1.1. The Contractor must furnish all personnel, equipment, tools, materials, supervision, and quality control necessary to remove existing Trane RTAF 230 ton chiller and replace with a new Trane RTAF 230 ton chiller, model number

RTAF230EUAHHXUA1N21X3NLNCCV1XAXBXXXAA1XXXX

2.1.2. Replacement chiller shall be an air cooled Trane RTAF 230 ton chiller with variable compressors and shall be installed in accordance with this specification and perform at the specified conditions as scheduled:

2.1.2.1. Operation

• Chiller shall be able to start and operate in ambient conditions from 0F – 125F.

Wide ambient operation is accomplished with factory installed ant tested protection. If field installed wide ambient solution is used, this shall be purchased and installed at contractor expense.

• Chiller shall be capable of operating with a leaving solution temperature range of 40F – 65F without use of glycol.

• Chiller shall be capable of starting with 95F entering fluid temperature to the evaporator.

• Chiller shall provide evaporator freeze protection and low limit control to avoid low evaporator refrigerant nuisance trips during critical periods of operation.

Whenever this control is in effect, the controller shall indicate that the chiller is in adaptive mode; if low ambient/freeze conditions exist longer than 30 seconds, a limit warning alarm shall energize.

• Rapid restart after power restoration. Chiller shall be capable of starting in 45 seconds.

2.1.2.2. Compressors

• Compressors shall be variable speed compressors

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• Provide direct drive motor cooled by suction gas with only three major moving parts and a completely enclosed compression chamber that leads to increased efficiency.

• Each compressor shall have internal overload protection.

• Each compressor shall include centrifugal oil pump, oil level sight glass and oil charging valve.

• Each compressor shall have crankcase heaters installed and properly sized to minimize the amount of liquid refrigerant present in the oil sump during off cycles.

2.1.2.3. Fans

• Low sound fans shall be dynamically balanced and direct driven.

• All condenser fan TEAO motors shall have permanently lubricated ball bearings and external overload protection.

2.1.2.4. Chiller Construction

• Frame, panels, and access doors shall be constructed of galvanized steel.

2.1.2.5. Chiller Mounted Starter

• The starter shall be across-the-line configuration, factory mounted and fully prewired to the compressor motors and control panel.

• Units shall have single point power connection.

• Control power transformers shall be factory installed and wired.

• Control panel shall be dead front construction for enhanced service technician safety.

• Unit wiring shall be run in liquid tight conduit.

• Power line connection shall be standard with a terminal block.

2.1.2.6. Refrigerant Circuit

• Chiller shall have 2 refrigerant circuits, each with two manifolded compressors.

• Each refrigerant circuit shall include:

o Liquid line shutoff valve o Discharge service valve o Filter o Liquid line sight glass o Electronic expansion valve sized for maximum operating pressure o Charging Valve

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• Full operating charge of R410A and oil.

2.1.2.7. Controls

• Controls shall be factory mounted to the control panel door.

• Operator interface shall have an LCD touch screen display.

• The display shall include a menu driven interface with touch screen navigation to organized sub-system reports for compressors, evaporators, motor information, and diagnostics.

• The interface shall provide password protection of all setpoints.

• The chilled water temperature control shall be microprocessor based and show water and refrigerant temperatures, refrigerant pressure, and diagnostics. The control shall be supplied with the chiller by the manufacturer.

• The front of the chiller control panel shall display the following without codes, tables, or gauges:

o Run time o Number of starts o Current operating mode o Chilled water setpoint and setpoint source o Electrical current limit setpoint and setpoint source o Entering and leaving evaporator water temperatures o Saturated evaporator and condenser refrigerant temperatures o Oil pressure o Phase reversal/imbalance/single phasing and over/under voltage protection o Low chilled water temperature protection o High and low refrigerant pressure protection o Load limit thermostat to limit compressor loading on high return water temperature o Condenser fan sequencing to automatically cycle fans in response to load, expansion valve pressure, condenser pressure, and differential pressure.

o Display diagnostics o Compressor status, RLA percentage, anti-short cycle timer, and automatic compressor lead-lag.

• On chiller, mount weatherproof control panel, containing starters, power and control wiring, factory wired with terminal block power connection. Provide primary and secondary fused control power transformer.

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• The chiller controller shall utilize a microprocessor that will automatically take action to prevent chiller shutdown due to abnormal conditions associated with evaporator refrigerant temperature, high condensing pressure, and motor current overload.

• Provide the following safety controls with indicating lights or diagnostic readouts:

o Low chilled water protection o High refrigerant pressure.

o Loss of chilled water flow.

o Contact for remote emergency shutdown.

o Motor current overload.

o Phase reversal/unbalance/single phasing.

o Over/under voltage.

o Failure of water temperature sensor used by controller.

o Compressor status (on or off).

• Provide the following operating controls:

o A variable method to control capacity to maintain leaving chilled water temperature based on PI algorithms. Five minute solid state anti-recycle timer to prevent compressor from short cycling. Compressor minimum stop-to-start time limit shall be 2 minutes. If a greater than 5 minute start-to-start, or greater than 2 minute stop-to-start timer is included, hot gas bypass shall be provided to insure accurate chilled water temperature control in light load applications.

o Chilled water pump output relay that closes when the chiller is given a signal to start.

o Load limit thermostat to limit compressor loading on high return water temperature to prevent nuisance trip outs.

o High ambient unloader pressure controller that unloads compressors to keep head pressure under control and help prevent high pressure nuisance trip outs on days when outside ambient is above design.

o Compressor current sensing unloader chiller that unloads compressors to help prevent current overload nuisance trip outs.

o Low ambient lockout control with adjustable setpoint.

o Condenser fan sequencing which adjusts the speed of all fans automatically in response to ambient, condensing pressure and expansion valve pressure differential thereby optimizing chiller efficiency.

• Provide user interface on the front of the panel. If display is on the inside of the panel, then a control display access door shall be provided to allow access to the display without removal of panels. Provide user interface with a minimum of the following features:

Poplarville, MS – Replace 230 ton Trane Chiller Page 7 of 16 o Leaving chilled water setpoint adjustment from LCD input o Entering and leaving chilled water temperature output o Pressure output of condenser o Pressure output of evaporator o Ambient temperature output o Voltage output o Current limit setpoint adjustment from LCD input.

• The chiller control panel shall provide leaving chilled water temperature reset based upon return water temperature.

• The chiller control panel shall provide an alarm relay output that shall energize whenever a fault requiring manual reset is detected by the panel.

• Chiller shall have full architectural louvers panels.

• Chiller shall ship with elastomeric isolators

2.2. Contractor Requirements

• Possess all appropriate valid and current HVAC license(s) from the State of Mississippi.

• Disconnect and remove, using contractor provided rigging and crane, the existing air-cooled chiller and all associated components required for the installation of the new chiller system and dispose of properly and legally at an off-site location.

• Install the new air-cooled Trane chiller ( RTAF-230) in accordance with all manufacturer's requirements and recommendations to include proper refrigerant

• Provide all labor and materials to perform startup. Startup shall be performed by a factory-trained technician from the original equipment manufacturer (OEM).

Technician shall confirm that equipment has been correctly installed and passes specification checklist prior to equipment becoming operational and covered under OEM warranty. This shall be done in strict accordance with manufacturer's specifications and requirements. Third-party service agencies are not permitted.

• A start-up log shall be furnished by the factory approved start-up technician to document the chiller's start-up date and shall be signed by the owner or his authorized representative prior to commissioning the chillers.

• In addition to the manufacturer’s warranty, the contractor shall provide a minimum 1 year parts and labor warranty on all components used in the installation.

• Provide and install all necessary electrical components, wiring, and connections.

• Provide and install all necessary mechanical piping to allow for proper start-up, loop chemical balance testing, and flow balancing. Supply and return chilled

Poplarville, MS – Replace 230 ton Trane Chiller Page 8 of 16 water piping shall include air vents, pressure gauges w/ shutoff valves, thermometers, flow meters, isolation valves, balancing valves, relief valves and/or any other devices/materials specified in the chiller manufacturer’s installation instructions. All exposed piping is to be properly insulated and heat traced.

• Perform leak test and check for proper operation.

• Integrate new chiller into the present HVAC Controls system.

• Provide all operations and maintenance manuals to owner representative prior to close out of contract.

• Existing concrete pad is to be re-used.

2.3. The Contractor will verify all dimensions and site conditions prior to beginning work.

No Government equipment will be available for use by the Contractor. The Contractor must provide their own restroom facility.

2.4. Site Photographs

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Figure 1 Chiller #1 and Chiller #2

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Figure 4 Chiller #2 (to be replaced) DRAFT C

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2.5. LOCATION OF WORK

The project is located at 810 Hwy 26W, Poplarville, MS 39470.

2.6. SITE VISIT

Interested vendors are encouraged to visit the site and be escorted by a government representative to confirm locations, dimensions, and conditions of the project before a quote is submitted. The purpose of a site visit is to observe conditions relevant to the completion of this project. No consideration will be given to claims based on lack of knowledge of existing conditions, except where contract documents detail definite provisions for adjustment in cost or extension due to existing conditions not readily foreseeable.

3. PROJECT SCHEDULE

3.1. The completion of the project must not exceed 280 Days from the date of the contract award.

3.2. The Contractor must prepare an overall project schedule including milestone dates for all phases of work and completion date; submit to the COR for approval. This schedule is due fourteen (14) days after contract award. The Contractor must

Poplarville, MS – Replace 230 ton Trane Chiller Page 13 of 16 track all work progress to ensure that the project is completed according to the schedule. Include work week schedule with daily starting and stopping time.

3.3. The Contractor must coordinate and confirm the dates for all work with the COR. If necessary, any request for a time extension must be submitted to the Contracting Specialist in writing. Each request must include specific and detailed reasons in support of the schedule alteration and provide an updated schedule for completion.

No extension of the period of performance may be given without the written authority of the CO.

3.4. Project work hours are 7:00 am and 5:00 pm, local time, Monday through Friday;

federal holidays excluded. The contractor is not required to provide services on recognized Federal holidays established by Federal law (5 U.S.C. 6103). Any changes to work schedule must be submitted to CO for written approval prior to any schedule change.

4. GENERAL REQUIREEMENTS

4.1. PERMITS

The Contractor must obtain all building and trade permits necessary to include any drawings, plans, permit and inspection fees, utility location, site surveys, and any other items necessary for compliance with state, local, and federal building authorities.

4.2. EXISTING INSTALLATIONS/DEMOLITION

Coordinate removal of existing installations with COR. All disturbances of existing systems must be coordinated with the COR to prevent disconnecting equipment that may jeopardize on-going research.

4.3. QUALITY CONTROL

Provide quality control to ensure that all components of project work meet the requirements of the contract specifications. Ensure that all work not acceptable or compliant with the specifications is corrected prior to inspection or review by the COR. Quality control is the exclusive responsibility of the Contractor.

4.4. PROTECTION OF WORK AND PROPERTY/SAFETY REQUIREMENTS

4.4.1. The Contractor must protect the work, the site, and all existing property and structures within the limits of the construction activities or that may be affected until acceptance of the work. Any damage to property must be repaired at the Contractor’s expense to pre-damaged condition to the

Poplarville, MS – Replace 230 ton Trane Chiller Page 14 of 16 satisfaction of the COR.

4.4.2. Safety and health matters, as they relate to the work, are the exclusive responsibility of the Contractor. The Contractor must furnish, erect, and maintain barricades, warning lights, signs, guards, or take other precautions as may be required by law or local authorities of the protection and security.

4.4.3. Open depressions and excavations occurring as part of this work must be adequately barricaded or fenced to prevent vehicle or pedestrian traffic into the work area.

4.4.4. Provide continuous noise and dust abatement as required to prevent disturbance and nuisance to the public and workers and to the occupants of adjacent premises and surrounding areas. Dampen or cover areas affected by demolition operations as necessary to prevent dust nuisance.

4.4.5. The contract documents may not represent all surface conditions at the site and adjoining areas. The known surface conditions are as indicated and must be compared with actual conditions before commencement of work and the cost must be included in the Contractor’s quote.

4.4.6. The Government will not furnish any labor or equipment to unload or move materials or supplies.

5. UTILIZATION OF BIOBASED PRODUCTS

The Contractor must utilize products and material based from bio-based materials as applicable, (e.g. bio-based greases; bio-based hydraulic fluids, bio-based absorbents), to the maximum extent possible without jeopardizing the intended end use or detracting from the overall quality delivered to the Government. All supplies and materials must be of a type and quality that conform to the applicable federal specifications and standards.

All supplies and materials to be used in the performance of work described herein are subject to the approval of the Contracting Officer Representative (COR). Products can be found at: www.biopreferred.gov.

6. HAZARDOUS MATERIAL

All existing materials are believed to be free of asbestos containing materials. Existing conditions are reflected correctly to the best of USDA’s knowledge. The USDA makes no representation, warranty, or guaranty that the conditions indicated either are representative of those conditions existing throughout the area, or that unforeseen developments may not occur, or that materials other than, or proportions different from those indicated may not exist. The Contractor must include costs for hazardous

Poplarville, MS – Replace 230 ton Trane Chiller Page 15 of 16 materials assessment in the quote. If hazardous materials are found to be present, it must be reported to the CO & COR for further action.

7. DISPOSAL OF REMOVED MATERIALS AND DEBRIS

7.1. The Contractor must dispose of removed materials, waste, trash, and debris in a safe, acceptable manner, in accordance with applicable laws and ordinances and as prescribed by authorities having jurisdiction.

7.2. Burying of trash and debris on the site is prohibited. Burning of trash and debris at the site is prohibited.

7.3. Remove trash and debris from the site at frequent intervals so that its presence will not delay the progress of the work or cause hazardous conditions for workers and the public.

7.4. Removed materials, trash, and debris must become the property of the Contractor and must be removed from the project site and be disposed of in a legal manner.

Location of disposal site and length of haul are the Contractor's responsibility.

7.5. The Contractor should make every effort to recycle as much of the construction debris as possible.

7.6. Any waste materials encountered during the demolition that are found to contain lead, asbestos, polychlorinated biphenyls (PCB), fluorescent lamps, or any hazardous substances are to be handled and removed in accordance with local, state, and federal laws and requirements concerning hazardous waste as well as any specific hazardous waste requirements stated in different sections.

7.7. Comply with hauling and disposal regulations of authorities having jurisdiction, per federal, state, and local requirements.

8. TEMPORARY FACILITIES

Temporary utilities (water and electricity) may be furnished to the Contractor by the Government, if requested. The Contractor must maintain and protect all such utilities during the course of construction and must repair or replace any items damaged through its own negligence. Should the Contractor require any power or utility shutdowns during construction, the Contractor must obtain approval for such shutdown from the COR three

(3) working days prior to the need.

9. CLEANUP

The construction site must be kept clean and free of debris at all times. Restore areas

Poplarville, MS – Replace 230 ton Trane Chiller Page 16 of 16 disturbed as nearly as possible to the original appearance and condition. Upon completion of the project, and prior to final inspection, the Contractor must remove from the premises all unused material, trash, and debris resulting from the work to the satisfaction of the COR.

10. SUBMITTALS

Submittals on all material incorporated into the work, including shop drawings and specifications, used on this project must be submitted to the COR and Contracting Specialist. Electronic submittals are acceptable, otherwise three (3) written submittals are required.

10.1. Project Schedule within fourteen (14) days of award (see Section 3.2).

10.2. Operation and maintenance manual upon completion and commissioning.

10.3. Any additional material, including shop drawings and specifications, used on this project.

11. INSPECTION AND ACCEPTANCE

A government representative will inspect and approve the work performed on this project. The Contractor must schedule inspection a minimum of ten (10) days in advance, in writing, to the COR and CO. Any and all "Punch List" items that are the result of this inspection shall be completed within ten (10) days before final inspection.

12. FINAL PAYMENT/CONTRACT CLOSEOUT

The following documents are required prior to final payment (other documents may also be required): Release of Liens, Release of Claims, Employee Payroll\Timesheets, and Invoice.