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HomeMy WebLinkAboutCentrifugal Water ChillersIFB 283251 Specifications Attachment 1 SECTION 15684 CENTRIFUGAL WATER CHILLERS PART 1-GENERAL 1.1 SECTION INCLUDES A. Products: 1. Packaged, water cooled, electric motor driven, centrifugal water chillers including: a. Compressor -drive assembly. b. Refrigeration. c. Evaporator. d. Condenser. e.. .Factory insulation. f. Electrical. g. Variable Frequency Drive. h. Reduced Voltage Starter. i. Controls. j. Vibration isolators. k. Flow switches/differential pressure switches. 1. High efficiency purge unit (R-123 units only). 1.2 DEFINITIONS A. BAS: Building automation system (existing Trane System). B. COP: Coefficient of performance. The ratio of the rate of heat removal to the rate of energy input using consistent units for any given set of rating conditions. C. EER: Energy -efficiency ratio. The ratio of the cooling capacity given in terms of Btu/h to the total power input given in terms of watts at any given set of rating conditions. D. IPLV: Integrated part -load value. A single -number part -load efficiency figure of merit calculated per the method defined by ARI.550/590 and referenced to ARI standard rating conditions. E. kW/Ton: The ratio of total power input of the chiller in kilowatts to the net refrigerating capacity in tons at any given set of rating conditions. F. NPLV: Nonstandard part -load value. A single -number part -load efficiency figure of merit calculated per the method defined by ARI 550/590 and intended for operating conditions other than the ARI standard rating conditions. 1.3 CODES AND STANDARDS (UTILIZE MOST RECENT VERSION) A. Air -Conditioning & Refrigeration Institute 1. ARI 550/590: Water Chilling Packages Using the Vapor Compression Cycle 2. ARI 575: Method of Measuring Machinery Sound within an Equipment Space 3. ARI 580: Standard for Non -Condensable Gas Purge Equipment for Use with Low Pressure Liquid Centrifugal Chillers B American Society of Heating, Refrigerating and Air -Conditioning Engineers _ 1. ASHRAE 15: Safety Standard for Refrigeration Systems..; Facility Name _._, - ;- Prepurchase of Chillers Project Number Centrifugal Water Chillers Section 15684 -1 Date of Issue IFB 283251 Specifications Attachment 1 2. ASHRAE 34: Designation and Safety Classifications of Refrigerants 3. ASHRAE 147: Reducing the Release of Halogenated Refrigerants from Refrigerating and Air -Conditioning Equipment and Systems (ANSI) C. American Society of Heating, Refrigerating and Air -Conditioning Engineers/Illuminating Engineering Society of North America 1. ASHRAE/IESNA 90.1: Energy Standard for Buildings except Low -Rise Residential Buildings (ANSI) D. ASME International 1. ASME B16.5-2003: Pipe Flanges and Flanged Fittings, NPS 1/2 to NPS 24 2. 2004 ASME Boiler and Pressure Vessel Code: Section VIII, "Pressure Vessels," Division 1 E. ASTM International 1. ASTM C 534-03: Specification for Preformed Flexible Elastomeric Cellular Thermal Insulation in Sheet and Tubular Form F. 2007 Florida Energy Code (with 2009 Supplment) G. International Electrotechnical Commission 1. IEC 60947-4-1-2000: Part 4: "Contactors and Motor Starters"; Section 1, "Electromechanical Contactors and Motor Starters" (with Amendment 1, dated 2002) H. National Electrical Manufacturers Association 1. NEMA 250-2003: Enclosure for Electrical Equipment (1000 Volts Maximum) 2. NEMA AB 1-2002: Molded Case Circuit Breakers and Molded Case Switches 3. NEMA ICS 2-2000 (Addendum/Errata to Part 2 - 2003): Industrial Control and Systems: Controllers, Contactors, and Overload Relays, Rated 600 Volts 4. NEMA ICS 6-1993 (Revised 2001): Industrial Control and Systems: Enclosures 5. NEMA KS 1-2001: Enclosed and Miscellaneous Distribution Equipment Switches (600 Volts Maximum) I. NFPA 1. NFPA 70: National Electrical Code J. Underwriters Laboratories Inc. 1. UL 1995: Heating and Cooling Equipment 1.4 QUALITY ASSURANCE A. ARI Certification: Certify chiller according to ARI 550 certification program. B. ARI Rating: Rate chiller performance according to requirements in ARI 550/590. C. ASHRAE Compliance: 1. Comply with ASHRAE 15 for safety code for mechanical refrigeration. 2. Comply with ASHRAE 147 for refrigerant leaks, recovery, and handling and storage requirements. D. ASHRAE/IESNA Compliance: 1. Applicable requirements in ASHRAE/IESNA 90.1-2007. E. ASME Compliance: Centrifugal Water Chillers Section 15684 - 2 Date of Issue Facility Name Prepurchase of Chillers Project Number IFB 283251 Specifications Attachment 1 1. For Chillers charges with R-123 refrigerant: Fabricate and label chillers to comply with ASME Boiler and Pressure Vessel Code: Section VIII, Division 1. 2 For chillers charged with R-134a refrigerant, include an ASME U-stamp and nameplate certifying compliance. F. Comply with NFPA 70. G. Comply with requirements of UL and UL Canada, and include label by a qualified testing agency showing compliance. H. Conform to all national, state and local codes including Illinois Energy Code. 1.5 SUBMITTALS A. Manufacturers shall submit documentation indicating areas where the specification is exceeded and where the specification is not met. B. Submit the following performance data with your bid: 1. Submit product data indicating rated capacities, weights (delivered and operating), dimensions, required clearances, specialties and accessories, electrical requirements and wiring diagrams. Provide square footage of required insulation on the chiller. 2. Submit performance data indicating energy input versus cooling load output including kW per ton and NPLV, per ARI Standard 550/590, at 10°/o intervals. Ratings shall be based on constant chilled water and condenser water flow. Chilled water and condenser water flow rates and pressure drops shall also be included. 3. Submit sound data as follows: The centrifugal chiller sound pressure level (SPL), in decibels (dBa), with a reference pressure of 20 micropascals. All ratings shall be in accordance with ARI Standard 575. 4. See Section 2.2E and bid form for additional performance requirements. C. Successful bidder to submit compressor data indicating impeller speed (RPM), number of bearings, type of bearings, high speed impeller shaft, low speed compressor shaft, number of stages, number of sets of inlet guide vanes, amount of refrigerant charge (lbm) and amount of oil required (lbm). D. Submit shop drawings indicating components, assembly, dimensions, weights and loadings, required clearances and location and size of field connections. Submit complete electrical wiring diagrams indicating power, signal, and control wiring connections and field wiring requirements. Indicate equipment, piping and connections, valves, strainers and thermostatic valves required for a complete system. E. Provide characteristics of safety relief valves including location and quantity. F. Submit manufacturer's installation instructions including rigging, installation and start- up procedures. G. Submit operation and maintenance data for each chiller including emergency, operation, and maintenance procedures, maintenance schedules, and troubleshooting guide. H. Submit written certification that components of package not furnished by manufacturer have been selected in accordance with manufacturer's requirements. I. Provide source quality -control test reports. 1.6 DELIVERY, STORAGE AND HANDLING Facility Name Prepurchase of Chillers Project Number Centrifugal Water Chillers Section 15684 - 3 Date of Issue IFB 283251 Specifications Attachment 1 A. Deliver products to south Florida (FOB Destination) to location designated by Owner under provisions of Conditions of the Contract. Contact Owner three (3) business days prior to delivery to obtain delivery location. DO NOT deliver to jobsite. B. Units shall -be -fully assembled and tested at the factory prior to shipping. Ship chillers fully disassembled if available or with separable shells and driveline. The oil charge, relief device, and miscellaneous materials shall be packed separately. The refrigerant charge shall be shipped concurrently or separately in cylinders for field evacuation and charging of unit. Factory technician shall provide re -assembly supervision and startup of equipment. If unit ships fully assembled, provide disassembly supervision by factory technician. C. Comply with manufacturer's installation instructions for rigging, unloading and transporting units. D. Protect units from physical damage. Leave factory shipping covers in place until installation. 1.7 SPARE PARTS A. Provide a recommended list of spare parts that Owner shall purchase and keep on site. 1.8 WARRANTY A. Provide one (1) year warranty from date of start-up for entire chiller including starter/VFD under provisions of Conditions of the Contract. B. Include coverage for complete chiller package including materials and labor. C. Additive Alternate Bid 1: Provide 2nd-5th year extended parts and labor warranty on entire unit including starter/VFD (for a total of five (5) years with standard warranty from start-up). PART 2 - PRODUCTS 2.1 MANUFACTURERS A. York Model YKLQLRP8-CSG w/ Variable Frequency Drive (VFD) (Qty 2) York Model YKHQFVP9-CTG w/ Solid State Starter (Qty 1) B. Trane CVHF0570-080L-080L w/ VFD (Qty 2) Trane CVFH0650-080L-080L w/ Solid State Starter (Qty 1) 2.2 GENERAL REQUIREMENTS A. Furnish factory assembled and tested, packaged, water-cooled, liquid chiller consisting of centrifugal compressor, compressor motor, condenser, evaporator, lubrication system, Micro -Computer Control Center and all interconnecting piping and wiring, refrigeration accessories, instrument and control panel including gauges and indicating lights, auxiliary components and accessories and motor starters. Construction and ratings shall be in accordance with ARI 550/590. B. Units shall have full load and part load perfoiinance not less than prescribed by ANSI/ASHRAE 90.1. C.---The unit shall be capable of starting and operating.with reduced temperature cooling tower water of 60F during part -load operation. Centrifugal Water Chillers Section 15684 - 4 Date of Issue Facility Name Prepurchase of Chillers Project Number IFB 283251 Specifications Attachment 1 D. All exposed surfaces shall be primed and painted with manufacturer's standard paint system and colors. E. Furnish three (3) centrifugal water chillers with the following performance: 1. Refrigeration capacity: 620 tons 2. Motor voltage: 460/3/60 3. Full load power consumption: Must meet or exceed ASHRAE 90.1 4. Evaporator flow rate: 1260 gpm 5. Evaporator fluid: 100% water 6. Evaporator leaving fluid temp: 44 F 7. Evaporator entering fluid temp: 56 F 8. Evaporator fouling factor: 0.0001 ftz•hr•F/Btu 9. Evaporator pressure drop: 20 ft maximum 10. Condenser flow rate: 1457 gpm 11. Condenser fluid: 100% water 12. Condenser leaving fluid temp: 99F 13. Condenser entering fluid temp: 87F 14. Condenser fouling factor: 0.00025 ft2.hr•F/Btu 15. Condenser pressure drop: 20 ft maximum F. Unit shall be provided with neoprene pad vibration isolators. G. Alternate bids for chiller options are specified in various places throughout this section. These alternates are summarized as below: 1. Additive Alternate Bid 1— Extended Warranty: Provide 2nd-50, year extended parts and labor on entire unit including starter/variable frequency drive. 2.3 COMPRESSOR/MOTOR ASSEMBLY A. The compressor shall be a single or multi -stage centrifugal type driven by an open -drive or hermeticelectric motor. The housing shall be fully accessible with vertical circular joints, with the complete operating assembly removable from the compressor and scroll housing. .The rotor assembly shall consistof a heat -treated alloy steel drive shaft and impeller shaft with a cast aluminum, fully shrouded impeller. The impeller shall be designed for balanced thrust, dynamically balanced and overspeed tested for smooth, vibration -free operation. Insert -type joumal and thrust bearings shall be fabricated of aluminum alloy, precision bored and axially grooved. 1. Compressor castings for R-123 chillers shall be designed for 15 psig working pressure and hydrostatically pressure tested at 50 psig. . 2. Compressor castings for R-134a chillers shall be designed for 235 psig working pressure and hydrostatically pressure tested at 350 psig. B. Gear -driven or direct -drive compressor drivelines are acceptable. C. For gear -driven, drivelines, internal single helical gears with crowned teeth shall be designed so that more than one tooth is in contact at all times to provide even distribution of compressor load and quiet operation. Each gear shall be individually mounted in its ownjournal and thrust bearings to isolate it from impeller and motor :-forces. The shaft seal shall be a spring -loaded carbon ring with precision lapped collar Facility Name • -• •-. Prepurchase of Chillers Project Number Centrifugal Water Chillers Section 15684 - 5 Date of Issue IFB 283251 Specifications Attachment 1 cooled by oil during operation. A gravity -fed oil reservoir shall be built into the top of the compressor to provide lubrication during coastdown in the event of a power failure. D. Capacity control shall be achieved by use of pre -rotation vanes to provide fully modulating control from 100% to 15% of full load. Pre -rotation vane position shall be autoinatically controlled by an external electric actuator to maintain constant leaving chilled water temperature. Maintain stable operation that is free of surge, cavitation, and vibration throughout entire operating range. E. Lubrication System: Lubrication oil shall be force-fed to all bearings, gears and rotating surfaces by an oil pump which operates prior to start-up, continuously during operation and during coastdown. An oil reservoir, separate from the compressor, shall contain a submersible oil pump and immersion -type oil heater, thermostatically controlled to boil off refrigerant from the oil. Oil shall be filtered by an externally mounted 1/2 micron replaceable cartridge oil filter equipped with service valves and cooled by a refrigerant - cooled oil cooler before entering the compressor. An automatic oil return system to recover any oil that may have migrated to the evaporator shall be provided. Oil piping shall be completely factory installed and tested. F. Motor Driveline (Hermetic or Open) 1. Open Motor Driveline a. The compressor motor shall be an open drip -proof, squirrel cage, induction type operating at 3570 rpm. Motor shall be 460 volt, 3 phase, 60 hertz. b. The open motor shall be provided with a D flange, to allow it to be rigidly coupled to the compressor to provide factory alignment of motor and compressor shafts, and to allow access to motor for repair without first removing refrigerant charge from the chiller. c. Motor drive shaft shall be directly connected to the compressor shaft with a flexible disc coupling. Coupling shall have all metal construction with no wearing parts to assure long. life, and no lubrication requirements to provide low maintenance. d. Overload/overcurrent transformers shall be furnished with all units. For units furnished with factory packaged starters, refer to the Starter section. 2. Hermetic Motor Driveline a. Compressor motors are hermetically sealed two -pole, low -slip squirrel cage, induction -type operating at 3600 rpm. Motor shall be 460 volt, 3 phase, 60 hertz. The rotor shaft is of heat treated carbon steel and designed such that the first critical speed is well above the operating speed. Impellers are keyed directly to the motor shaft and locked in position. Nonferrous, labyrinth -type seals minimize recirculation and gas leakage between the stages of the compressor. A load -limit system provides protection against operation in excess of nameplate motor rating. Overload/overcurrent transformers shall be furnished with all units. For -units furnished with factory packaged starters, refer to the Starter section,.,_,,. b. c. d. G. Refrigerants Centrifugal Water Chillers Section 15684 - 6 Date of Issue Facility Name Prepurchase of Chillers Project Nurnber IFB 283251 Specifications Attachment 1 1. . Refrigerant shall be R-123 or R-134a. R-22 shall not be allowed. 2. The initial charge of refrigerant and oil shall be shipped separately. The services of a factory -trained representative shall be included to supervise initial start-up, final leak testing and charging. 2.4 CONDENSER (R-123 CHILLERS) A. Condenser shall be of the shell -and -tube type, two -pass, designed for 15 psig working pressure on the refrigerant side, and shall be tested at 50 psig. • B. Shell shall be fabricated from rolled carbon steel plate with fusion welded seams; have carbon steel tube sheets, drilled and reamed to accommodate the tubes; and intermediate tube supports spaced no more than four feet apart. C. Tubes shall be copper, high -efficiency, internally and externally enhanced type. Tubes shall be "skip fin" design, providing a smooth internal and external surface at each tube sheet support. Each tube shall be roller expanded into the tube sheets providing a leak -proof seal, and be individually replaceable. Water velocity through the tubes shall not exceed 12 feet per second. D. Refrigerant Relief Device: A frangible, carbon bursting disc relief device, sized to meet the requirements of the ASHRAE 15 Safety Code for Mechanical Refrigeration, shall be provided on the chiller. E. Provide 150 lb ANSI raised face flanges or grooved connections for condenser water connection, factory welded to water nozzles. F. A thermistor type temperature sensor shall be factory mounted in each nozzle connection. G. Water boxes shall be removable to permit tube cleaning and replacement. Water boxes shall be designed for 150 psig design working pressure and be tested at 225 psig. Vent and drain connections with plugs shall be provided on each water box. H. A refrigerant sub -cooler shall be provided for improved cycle efficiency. I. Provide positive shut off refrigerant isolation valves on compressor discharge and refrigerant liquid line allowing isolation and storage of complete refrigerant charge in the condenser for servicing. If shutoff valves are not available, service technician shall provide refrigerant storage vessel sized to hold charge while chiller is serviced for length of warranty period. 2.5 CONDENSER (R-134A) A. Condenser shall be of the shell -and -tube type, two -pass, designed for 235 psig working pressure on the refrigerant side. B. Shell shall be fabricated from rolled carbon steel plate with fusion welded seams; have carbon steel tube sheets, drilled and reamed to accommodate the tubes; and intermediate tube supports spaced no more than four feet apart. C. Tubes shall be copper, high -efficiency, internally and externally enhanced type. Tubes shall be "skip fin" design, providing a smooth internal and external surface at each tube sheet support. Each tube shall be roller expanded into the tube sheets providing a leak -proof seal, and be individually replaceable. Water velocity through the tubes shall not exceed 12 feet per second. Refrigerant Relief' Device: A reseatable relief device,.sized to meet'the._requirements of.-•..::,; the ASHRAE 15 Safety Code for Mechanical Refrigeration, shall -be provided on the Facility Name ‘ Centrifugal Water Chillers Prepurchase of Chillers Project Number Date of Issue Section 15684 - 7 • IFB 283251 Specifications Attachment 1 chiller condenser shell. Provide dual redundant relief devices on the condenser to allow for replacement of relief device without removing chiller refrigerant charge. E. Provide 150 lb ANSI raised face flanges or grooved connections for condenser water connection, factory welded -to water nozzles. A thermistor type temperature sensor shall be factory mounted in each nozzle connection. - F. Water boxes shall be removable to permit tube cleaning and replacement. Water boxes shall be designed for 150 psig design working pressure and be tested at 225 psig. Vent and drain connections with plugs shall be provided on each water box. G. Provide positive shut off refrigerant isolation valves on compressor discharge and refrigerant liquid lines allowing isolation and storage of complete refrigerant charge in the condenser for servicing. 2.6 EVAPORATOR (R-123) A. Evaporator shall be of the shell -and -tube, two -pass, flooded type designed for 15 psig working pressure on the refrigerant side, and shall be tested at 30 psig. B. Shell shall be fabricated from rolled carbon steel plate with fusion welded seams; have carbon steel tube sheets, drilled and reamed to accommodate the tubes; and intermediate tube supports spaced no more than four feet apart. C. Tubes shall be copper, high -efficiency, internally and externally enhanced type. Tubes shall be "skip fin" design, providing a smooth internal and external surface at each tube sheet support. Each tube shall be roller expanded into the tube sheets providing a leak -proof seal, and be individually replaceable. Water velocity through the tubes shall not exceed 12 feet per second. D. Refrigerant Relief Device: A frangible, carbon bursting disc relief device, sized to meet the requirements of the ASHRAE 15 Safety Code for Mechanical Refrigeration, shall be provided on the chiller. Additionally, provide reseating pressure valve downstream of the bursting disc to allow for common refrigerant relief piping. E. Provide 150 lb ANSI raised face flanges or grooved connections for chilled water connection, factory welded to water nozzles. A thermistor type temperature sensor shall be factory mounted in each nozzle connection. F. Water boxes shall be removable to permit tube cleaning and replacement. Water boxes shall be designed for 150 psig design working pressure and be tested at 225 psig. Vent and drain connections with plugs shall be provided on each water box. G. A liquid level sight glass shall be located on the side of the shell to aid in determining proper refrigerant charge. H. Aluminum mesh eliminators shall be located above the tube bundle to prevent liquid refrigerant carryover to the compressor. I. Refrigerant Flow Control: Refrigerant flow to the evaporator shall be controlled by a fixed orifice with no moving parts. 2.7 EVAPORATOR (R-134A) A. Evaporator shall be of the shell -and -tube, two -pass, flooded type designed for 235 psig working pressure on the refrigerant side. Centrifugal Water Chillers Section 15684 - 8 Date of Issue Facility Name Prepurchase of Chillers Project Number IFB 283251 Specifications Attachment 1 B. Shell shall be fabricated from rolled carbon steel plate with fusion welded seams; have carbon steel tube sheets, drilled and reamed to accommodate the tubes; and intermediate tube supports spaced no more than four feet apart. C. Tubes shall be copper, .high -efficiency, internally and externally enhanced type. Tubes shall be "skip fin" design, providing a smooth internal and external'surface at each tube sheet support. Each tube shall be roller expanded into the tube sheets providing a leak -proof seal, and be individually replaceable. Water velocity through the tubes shall not exceed 12 feet per second. D. Refrigerant Relief Device: A reseatable relief device, sized to meet the requirements of the ASHRAE 15 Safety Code for Mechanical Refrigeration, shall be provided on the chiller evaporator shell. E. Provide 150 lb ANSI raised face flanges or grooved connections for chilled water connection, factory welded to water nozzles. A thermistor type temperature sensor shall be factory mounted in each nozzle connection. F. Water boxes shall be removable to permit tube cleaning and replacement. Water boxes shall be designed for 150 psig design working pressure and be tested at 225 psig. Vent and drain connections with plugs shall be provided on each water box. G. A liquid level sight glass shall be located on the side of the shell to aid in determining proper refrigerant charge. H. Aluminum mesh eliminators shall be located above the tube bundle to prevent liquid refrigerant carryover to the compressor. I. Refrigerant Flow Control: Refrigerant flow to the evaporator shall be controlled by a variable orifice. 2.8 CONTROLS A. Each unit shall be furnished complete with a micro -computer control center in a locked enclosure, factory -mounted, wired and tested. The control center shall include a graphical display showing all system parameters in the English language with numeric data in English units. Provide full color graphical display if offered as an option. B. System operating information displayed locally shall include: return/leaving chilled water temperatures; return/leaving condenser water temperatures; evaporator/condenser refrigerant pressures; differential oil pressure; percent motor current; evaporator/condenser saturation temperatures; compressor discharge temperature; oil temperature; operating hours; and number of compressor starts. C. Security access shall be provided to prevent unauthorized changing of setpoints, and to select local or remote control of the chiller, and to allow manual operation of the pre - rotation vanes and oil pump. D. Digital programming of essential setpoints through a color coded, tactile -feel keypad shall include: leaving chilled water temperature; percent current limit; pulldown demand limiting; seven-day time clock for starting and stopping chiller, pumps, and tower (complete with holiday schedule); and remote reset temperature range. All safety and cycle shutdowns shall be annunciated through the alphanumeric display and consist of day, time, cause of shutdown, arid type ofrestart required.. Safety. shutdowns shall include: high condenser pressure; low oil pressure; high oil temperature; high oil pressure; high compressor discharge temperature; low evaporator E. Facility Name = Prepurchase of Chillers Project Number Centrifugal Water Chillers Section 15684 9 Date of Issue IFB 283251 Specifications Attachment 1 pressure; motor controller fault-, and sensor malfunction. Cycling shutdowns shall include: low water temperature; cooler/condenser water flow interruption; power fault; internal time clock; and anti -recycle. F. Control center shall be able to interface with existing Trane Building Automation System (BAS) to provide remote chiller start/stop; reset of chilled water supply temperature; and reset of current limit. G. Provide additional hardware as necessary to provide the following information through the existing Trane BAS system: chilled water temperatures; motor amperages; motor voltages; refrigerant pressures; oil temperature and pressure; and status messages indicating chiller is ready to start, chiller is operating, chiller is shut down on a safety requiring reset, and chiller is shut down on a recycling safety. Include startup services and troubleshooting in conjunction with hardware. 2.9 HIGH EFFICIENCY PURGE UNIT (R-123 CHILLERS) A. The chiller shall be supplied with a factory mounted purge unit providing a positive means for collection and removal of non-condensables from the system. It shall be capable of removing refrigerant from the non-condensables and returning it to the chiller. It shall have high efficiency in recapturing the refrigerant at all load and head conditions. It shall operate automatically and only while the chiller is operating to maintain its high efficiency. B. A message shall be provided on the control panel which shall alert the operator at occurrence of excessive purging, indicating an abnormal air leak into the unit. C. The purge unit shall include necessary operating controls, piping, and refrigerant service valves to isolate the purge unit from the chilling unit. The purge unit shall be refrigerant cooled to provide a constant low temperature source for high efficiency purging. D. Emissions should be no greater than 0.02 lb of refrigerant per pound of air when rated according to ARI 580. ... E. Purge unit relief valve shall be factory piped downstream of rupture disk. 2.10 INSULATION . A. Units shall be field insulated by contractor. Provide square footage of insulation required in submittal. 2.11 FLOW SWITCHES A. Provide factory mounted thermal proof of flow sensors in condenser and evaporator. B. If a factory mounted proof of flow temperature sensor is not available, provide differential pressure. switch; United Electric Model J21K-150; NEMA 1; 150 psi DWP;'/a" NPTI pressure connection; 15 amp at 115V; Class B switch SPDT; auto -reset; high and low pressure bellows stops; shipped loose for contractor field installation in condenser water and chilled water piping. 2.12 VARIABLE FREQUENCY DRIVE (SEE 2.1 FOR APPLICABLE CHILLERS) A. A variable speed drive shall be factory installed on the chiller. It shall vary the compressor motor speed by controlling the frequency and voltage of the electrical power to the motor. The adaptive capacity control logic shall automatically adjust motor speed and compressor ire -rotation vane position independently for maximum part -load efficiency by analyzing information fed to it by sensors located throughout the chiller. Centrifugal Water Chillers Section 15684 -10 • Date of Issue Facility Name Prepurchase -of -Chillers Project Number IFB 283251 Specifications Attachment 1 B. Drive shall be PWM type utilizing IGBTs with a power factor of 0.95 or better at all loads and speeds. C. The variable speed drive shall be unit mounted in a NEMA-1 enclosure with all power and control wiring between•the drive and chiller factory furnished, including power to the chiller oil pump. Field power wiring shall be a single point connection and electrical lugs for incoming power wiring shall be provided. The entire chiller package shall be UL listed. Variable speed drive shall be D. The following features shall be provided: a door interlocked circuit breaker with 65,000 amp short circuit withstand in accordance with UL 508; capable of being padlocked; UL listed ground fault protection; overvoltage and undervoltage protection; single phase protection, insensitive to phase rotation; overtemperature protection; digital readout at the chiller unit control panel of: 1. Output frequency. 2. • . Output voltage. 3. Three phase current and voltage output A, B, C legs. 4. Input kilowatts (kW) and kilowatt hours (kWh). 5. Motor current % full load amps (FLA). 6. Self -diagnostic service parameters. 2.13 REDUCED VOLTAGE SOLID STATE STARTER (SEE 2.1 FOR APPLICABLE CHILLER) A. The chiller manufacturer shall furnish a reduced voltage Solid -State Starter for the compressor motor. Starter shall ship loose as necessary for rigging into building. B. The starter shall provide, through the use of silicon controlled rectifiers, a smooth acceleration of the motor without current transitions or transients. C. The starter shall be unit -mounted in a NEMA 1 enclosure, with all power and control wiring between the drive and the chiller factory furnished, including power to the oil pump. Provide with hinged door capable of being padlocked. Electrical lugs for incoming power wiring shall be provided. D. The following features shall be provided: door interlocked circuit breaker with 65,000 amp short circuit withstand rating in accordance with UL 508; 115 volt control transformer; three -leg sensing overloads; phase rotation and single-phase failure protection; high temperature safety protection; motor current imbalance and undervoltage safeties; open and close SCR protection; momentary power interruption protection; digital readout at the chiller unit control panel of: 1. Three phase current and voltage output A, B, C legs. 2. Input power (kW) and kilowatt hours (kWh). 3. Motor current % full load amps (FLA). 4. Self -diagnostic service parameters. -- END OF SECTION -- Facility Name Prepurchase of Chillers • Project Number Centrifugal Water Chillers Section 15684 - 111 - Date of Issue