CT1507B035 TENDER FOR THE REPLACEMENT OF CHILLER SYSTEMS AT SATS AFT 6, 20 AIRLINE ROAD, SINGAPORE PART VI TECHNICAL SPECIFICATIONS SECTION 1

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1 PART VI TECHNICAL SPECIFICATIONS SECTION 1 CHILLER TS-CH-1

2 TECHNICAL SPECIFICATION OF 1 GENERAL CHILLER 1.1 SYSTEM DESCRIPTION Microprocessor-controlled liquid chiller with single/multi compressors (VFD), using refrigerant HFC-134a only. Refrigerant offered shall not have a planned phase out date. 1.2 QUALITY ASSURANCE A. performance shall be rated in accordance with ARI Standard 550/ B. Equipment and installation shall be in compliance with ANSI/ASHRAE 15 (latest edition). C. Cooler and condenser refrigerant side shall include ASME U stamp and nameplate certifying compliance with ASME Section VIII, Division 1 code for unfired pressure vessels. D. A manufacturer s data report is required to verify pressure vessel construction adherence to ASME vessel construction requirements. Form U-1 as required per ASME code rules is to be furnished to the owner. The U-1 Form must be signed by a qualified inspector, holding a National Board Commission, certifying that construction conforms to the latest ASME Code Section VIII, Div. 1 for pressure vessels. The ASME symbol U must also be stamped on the heat exchanger. Vessels specifically exempted from the scope of the code must come with material, test, and construction methods certification and detailed documents similar to ASME U-1; further, these must be signed by an officer of the company. E. shall be designed and constructed to meet UL and UL of Canada requirements and have labels appropriately affixed. F. Each compressor assembly shall undergo a mechanical run-in test to verify vibration levels, oil pressures, and temperatures are within acceptable limits. Each compressor assembly shall be proof tested at a minimum 204 psig (1407 kpa) and leak tested at 185 psig (1276 kpa) with a tracer gas mixture. G. Entire chiller assembly shall be proof tested at 204 psig (1407 kpa) and leak tested at 185 psig (1276 kpa) with a tracer gas mixture on the refrigerant side. The leak test shall not allow any leaks greater than 0.5 oz per year of refrigerant. The water side of each heat exchanger shall be hydrostatically tested at 1.3 times rated working pressure. H. Prior to shipment, the chiller automated controls test shall be executed to check for proper wiring and ensure correct controls operation. I. The starter shall be variable frequency drive (VFD) with build in Harmonic Filter. TS-CH-2

3 1.3 DELIVERY, STORAGE AND HANDLING A. Unit shall be stored and handled in accordance with manufacturer s instructions. B. Unit shall be shipped with all refrigerant piping and control wiring factoryinstalled. C. Unit shall be shipped charged with oil and full charge of refrigerant HFC-134a or a nitrogen holding charge as specified on the equipment schedule. D. Unit shall be shipped with firmly attached labels that indicate name of manufacturer, chiller model number, chiller serial number, and refrigerant used. E. If the unit is to be exported, the manufacturer shall provide sufficient protection against sea water corrosion, making the unit suitable for shipment in a standard open top ocean shipping container. 1.4 WARRANTY Warranty shall include parts and labor for 12 months from date of completion. A refrigerant warranty shall be provided for a period of five years. 2 PRODUCTS 2.1 EQUIPMENT A. General: Factory-assembled, single piece, liquid chiller shall consist of compressor, motor, lubrication system, cooler, condenser, initial oil and refrigerant operating charges, microprocessor control system, and documentation required prior to start-up. B. Compressor: 1. Single/multiple, screw/centrifugal compressor of the high performance type. 2. Compressor and motor shall be open type or hermetically sealed into a common assembly and arranged for easy field servicing. 3. The compressor motor shall be accessible for servicing without removing the compressor base from the chiller. Connections to the compressor casing shall use O-rings and gaskets to reduce the occurrence of refrigerant leakage. Connections to the compressor shall be flanged or bolted for easy disassembly. 4. Compressor bearings must have individual design life of 50,000 hours or greater. 5. Compressor shall provide capacity modulation from 100% to 20% capacity without the use of hot gas bypass or mechanical unloaders. 6. Compressor shall be provided with a factory-installed positive pressure lubrication system to deliver oil under pressure to bearings and rotors at all operating conditions. Lubrication system shall include: a. Oil pump with factory-installed motor contactor with overload protection. TS-CH-3

4 b. Oil pressure sensor with differential readout at main control center. c. Oil pressure regulator. d. Oil filter with isolation valves to allow filter change without removal of refrigerant charge. e. Oil sump heater [115 V, 50 or 60 Hz] controlled from unit microprocessor. f. Oil reservoir temperature sensor with main control center digital readout. g. All wiring to oil pump, oil heater, and controls shall be pre-wired in the factory and power shall be applied to check proper operation prior to shipment. 7. Compressor shall be fully field serviceable. Compressors that must be removed and returned to the factory for service shall be unacceptable. 8. Acoustical attenuation shall be provided as required, to achieve a maximum (full load or part load) sound level, measured per ARI Standard 575 (latest edition). C. Motor: 1. Compressor motor shall be of the open-type/semi-hermetic, air or liquid refrigerant cooled, squirrel cage, induction type suitable for voltage shown on the equipment schedule. 2. For hermetic motors, it shall be suitable for operation in a refrigerant atmosphere and shall be cooled by atomized refrigerant in contact with the motor windings. 3. Motor stator shall be arranged for service or removal with only minor compressor disassembly and without removing main refrigerant piping connections. 4. Full load operation of the motor shall not exceed nameplate rating. 5. Three motor winding temperature sensors shall be provided. 6. An Electric heater shall be added for open-type motor to prevent moisture inside motor insulation D. Evaporator and Condenser: 1. Evaporator and condenser shall be of shell and tube type construction, each in separate shells. Units shall be fabricated with high-performance tubing, steel shell and tube sheets with fabricated steel waterboxes. Waterboxes shall be nozzle-in-head type with stub out nozzles having Victaulic grooves to allow for use of Victaulic couplings. 2. Tubing shall be copper, high-efficiency type, with integral internal and external enhancement unless otherwise noted. Tubes shall be nominal 3/4-in. OD with minimum wall thickness of in. measured at the root of the fin unless otherwise noted. Tubes shall be rolled into tube sheets and shall be individually replaceable. Tube sheet holes shall be double grooved for joint structural integrity. Intermediate support sheet spacing shall not exceed 36 in. (914 mm). 3. Condenser Waterboxes and nozzle connections shall be designed for 150 psig (1034 kpa) minimum working pressure; Cooler Waterboxes and nozzle connections shall be designed for 150 psig (1034 kpa) minimum working pressure, unless otherwise noted. Nozzles should have grooves to allow use of Victaulic couplings. TS-CH-4

5 4. The tube sheets and waterboxes of the cooler and condenser shall be epoxy coated from the factory and bolted together to allow for field disassembly and reassembly. 5. The vessel shall display an ASME nameplate that shows the pressure and temperature data and the U stamp for ASME Section VIII, Division 1. A reseating pressure relief valve(s) shall be installed on each heat exchanger. If a non-reseating type is used, a backup reseating type shall be installed in series. 6. Waterboxes shall have vents, drains, and covers to permit tube cleaning within the space shown on the drawings. A thermistor type temperature sensor with quick connects shall be factory-installed in each water nozzle. 7. Cooler shall be designed to prevent liquid refrigerant from entering the compressor. Devices that introduce pressure losses (such as mist eliminators) shall not be acceptable because they are subject to structural failures that can result in extensive compressor damage. 8. Tubes shall be individually replaceable from either end of the heat exchanger without affecting the strength and durability of the tube sheet and without causing leakage in adjacent tubes. E. Refrigerant Flow Control: To improve part-load efficiency, for chiller with capacity exceed 300 RT, liquid refrigerant shall be metered from the condenser to the cooler using a float-type metering valve or variable orifice to maintain the proper liquid level of refrigerant in the heat exchangers under both full and part load operating conditions. By maintaining a liquid seal at the float valve, bypassed hot gas from the condenser to the cooler is eliminated. For chiller with smaller capacity and multi compressors, electronic expansion valve may be used for the refrigerant flow control. F. Controls, Safeties, and Diagnostics: 1. Controls: a. The chiller shall be provided with a factory-installed and factory-wired microprocessor control center. The control center shall include an user friendly interface with display, visible start/stop button, alarm light and adequate text message. Display with code message is not acceptable. b. All chiller and motor control monitoring shall be displayed at the chiller control panel. c. The controls shall make use of non-volatile memory. d. The chiller control system shall have the ability to interface and communicate directly to the building control system. e. The default standard display screen shall simultaneously indicate the following minimum information: 1) Date and time of day 2) 24-character primary system status message 3) 24-character secondary status message 4) operating hours 5) Entering chilled water temperature 6) Leaving chilled water temperature TS-CH-5

6 7) Evaporator refrigerant temperature 8) Entering condenser water temperature 9) Leaving condenser water temperature 10) Condenser refrigerant temperature 11) Oil supply pressure 12) Oil sump temperature 13) Percent motor rated load amps (RLA) f. In addition to the default screen, status screens shall be accessible to view the status of every point monitored by the control center including: 1) Evaporator pressure 2) Condenser pressure 3) Compressor speed 4) Bearing oil supply temperature 5) Compressor discharge temperature 6) Motor winding temperature 7) Number of compressor starts 8) Control point settings 9) Discrete output status of various devices 10) Optional spare input channels 11) Line current and voltage for each phase 12) Frequency, kw, kwhr, demand kw g. Schedule Function: The chiller controls shall be configurable for manual or automatic start-up and shutdown. In automatic operation mode, the controls shall be capable of automatically starting and stopping the chiller according to a stored user programmable occupancy schedule. The controls shall include built-in provisions for accepting: 1) A minimum of two 365-day occupancy schedules. 2) Minimum of 8 separate occupied/unoccupied periods per day 3) Daylight savings start/end 4) 18 user-defined holidays 5) Means of configuring occupancy timed override 6) start-up and shutdown via remote contact closure h. Service Function: The controls shall provide a password protected service function which allows authorized individuals to view an alarm history file which shall contain the last 25 alarm/alert messages with time and date stamp. These messages shall be displayed in text form, not codes. i. Network Window Function: Each chiller control panel shall be capable of viewing multiple point values and statuses from other like controls connected on a common network, including controller maintenance data. The operator shall be able to alter the remote controller s set points or time schedule and to force point values or statuses for those points that are operator forcible. The control panel shall also have access to the alarm history file of all like controllers connected on the network. TS-CH-6

7 j. Pump Control: Upon request to start the compressor, the control system shall start the chilled and condenser water pumps and shall verify that flows have been established. k. Ramp Loading: A user-configurable ramp loading rate, effective during the chilled water temperature pull down period, shall prevent a rapid increase in compressor power consumption. The controls shall allow configuration of the ramp loading rate in either degrees per minute of chilled water temperature pull down or percent motor amps per minute. During the ramp loading period, a message shall be displayed informing the operator that the chiller is operating in ramp loading mode. l. Chilled Water Reset: The control center shall allow reset of the chilled water temperature set point based on any one of the following criteria: 1) Chilled water reset based on an external 4 to 20 ma signal. 2) Chilled water reset based on a remote temperature sensor (such as outdoor air). 3) Chilled water reset based on water temperature rise across the evaporator. m. Demand Limit: The control center shall limit amp draw of the compressor to the rated load amps or to a lower value based on one of the following criteria: 1) Demand limit based on a user input ranging from 40% to 100% of compressor rated load amps 2) Demand limit based on external 4 to 20 ma signal. n. Controlled Compressor Shutdown: The controls shall be capable of being configured to soft stop the compressor. The display shall indicate shutdown in progress. 2. Safeties: a. Unit shall automatically shut down when any of the following conditions occur (each of these protective limits shall require manual reset and cause an alarm message to be displayed on the control panel screen, informing the operator of the shutdown cause): 1) Motor overcurrent 2) Over voltage* 3) Under voltage* 4) Single cycle dropout* 5) Low oil sump temperature 6) Low evaporator refrigerant temperature 7) High condenser pressure 8) High motor temperature 9) High compressor discharge temperature 10) Low oil pressure 11) Prolonged stall TS-CH-7

8 12) Loss of cooler water flow 13) Loss of condenser water flow * Shall not require manual reset or cause an alarm if auto-restart after power failure is enabled. b. The control system shall detect conditions that approach protective limits and take self-corrective action prior to an alarm occurring. The system shall automatically reduce chiller capacity when any of the following parameters are outside their normal operating range: 1) High condenser pressure 2) High motor temperature 3) Low evaporator refrigerant temperature 4) High motor amps c. During the capacity override period, a pre-alarm (alert) message shall be displayed informing the operator which condition is causing the capacity override. Once the condition is again within acceptable limits, the override condition shall be terminated and the chiller shall revert to normal chilled water control. If during either condition the protective limit is reached, the chiller shall shut down and a message shall be displayed informing the operator which condition caused the shutdown and alarm. d. Internal built in safeties shall protect the chiller from loss of water flow. Differential pressure switches shall not be allowed to be the only form of freeze protection. 3. Diagnostics and Service: A self diagnostic controls test shall be an integral part of the control system to allow quick identification of malfunctioning components. Once the controls test has been initiated, all pressure and temperature sensors shall be checked to ensure they are within normal operating range. A pump test shall automatically energize the chilled water pump, condenser water pump, and oil pump. The control system shall confirm that water flow and oil pressure have been established and require operator confirmation before proceeding to the next test. In addition to the automated controls test, the controls shall provide a manual test which permits selection and testing of individual control components and inputs. A thermistor test and transducer test shall display on the ICVC screen the actual reading of each transducer and each thermistor installed on the chiller. All out-of-range sensors shall be identified. Pressure transducers shall be serviceable without the need for refrigerant charge removal or isolation. G Electrical Requirements: 1. The tenderer shall supply and install main electrical power line, disconnect switches, circuit breakers, and electrical protection devices per local code requirements and as indicated necessary by the chiller manufacturer. 2. The tenderer shall wire the chilled water pump and flow, condenser water pump and flow, and tower fan control circuit to the chiller control circuit. 3. The tenderer shall supply and install electrical wiring and devices required to interface the chiller controls with the building control system if applicable. TS-CH-8

9 4. Electrical power shall be supplied to the unit at the voltage, phase, and frequency listed in the equipment schedule. H. Piping Requirements Instrumentation and Safeties: Mechanical tenderer shall supply and install pressure gages in readily accessible locations in piping adjacent to the chiller such that they can be easily read from a standing position on the floor. Scale range shall be such that design values shall be indicated at approximately mid-scale. Gages shall be installed in the entering and leaving water lines of the cooler and condenser. I. Vibration Isolation: manufacturer shall furnish 2 spring isolator for mounting equipment on a level concrete surface. J. Start-Up: 1. The chiller manufacturer shall provide a factory-trained representative, employed by the chiller manufacturer, to perform the start-up procedures as outlined in the Start-Up, Operation and Maintenance manual provided by the chiller manufacturer. 2. Manufacturer shall supply the following literature: a. Start-up, operation and maintenance instructions. b. Installation instructions. c. Field wiring diagrams. d. One complete set of certified drawings. K. Site Performance Test : Site Performance Test by Accredited ESCO. The accredited ESCO shall be an objective party with ISO 9001:2000 and 14001:2004 certifications and must not connected to equipment or system sales. 1. The Chilled /Condenser Water Supply / Return Temperatures will be measured and logged at one-minute intervals using high accuracy thermistors for: Chilled /Condenser Water Temperature Profile a. Supply Temperature profile (super-imposed) b. Supply Temperature Histogram in percentage during operating hours only c. Return Temperature profile (Super-imposed) d. Return Temperature Histogram in percentage during operating hours only e. Chilled Water Temperature differential Histogram during operating hours only 2. Chilled /Condenser Water flow rate will be measured at one-minute intervals using high accuracy ultrasonic flow meter so as to plot the followings: Chilled /Condenser Water flowrate profile of each chiller (Super-imposed) TS-CH-9

10 3. The Power Consumption of each chiller will be logged at one-minute intervals using high accuracy power meters. a. kw profile (Super-imposed) b. Real-time 3 phase Power factor profile (Super-imposed) c. Histogram of Power factor occurrence d. Provide voltage unbalance occurrence using bin method based on NEMA standards MG e. Provide current unbalance occurrence using bin method based on NEMA standards MG Tonnage a. Tonnage profile of each chiller using super-imposed plot b. tonnage Histogram in percentage during operating hours only c. Tonnage vs percentage full load ampere. 5. Efficiency Measurement The Efficiency obtained from data acquisition should comprise of the following charts: Correlation between individual chiller operating tonnage and chiller efficiency L. Accessories: 1. Soleplate Package: Unit manufacturer shall furnish a soleplate package consisting of soleplates, jacking screws, leveling pads, and neoprene pads. 2. Spring Isolators: Spring isolators shall be field furnished and selected for the desired degree of isolation. 3. Spare Sensors with Leads: Unit manufacturer shall furnish additional temperature sensors and leads. 4. Sound Insulation Kit: Unit manufacturer shall furnish a sound insulation kit that covers the compressor housing, motor housing, compressor discharge pipe, condenser shell, suction line, evaporator, and economizer. Insulation design shall accommodate temperature and pressure sensors, gages, tubing, piping and brackets. 5. Chilled Plant Automation System Interface (BACnet ): The chiller control system shall have the ability to interface and communicate directly to the CPA using a BACnet based system. 6. The chiller shall ship from the factory charged with Nitrogen to 15PSI. 7. Field installed Thermal Insulation (Class 1 armaflux): Tenderer shall insulate the cooler shell, condenser shell (lower half) economizer, suction elbow, motor shell and motor cooling lines. Insulation shall be 2 layer of 1 in. (25.4 mm) thick with a thermal conductivity not exceeding w/m, and shall conform to UL standard 94, classification 94 HF-1. TS-CH-10

11 8. Cooler and Condenser Passes: Unit manufacturer shall provide the cooler and/ or condenser with minimum 2 pass configuration on the water side. 9. Nozzle-In-Head, 150 psig (1034 kpa): Unit manufacturer shall furnish nozzle-in-head style waterboxes on the cooler and/or condenser rated at 150 psig (1034 kpa). 10. Compressor Discharge Isolation Valve and Liquid Line Ball Valve: These items shall be factory-installed to allow isolation of the refrigerant charge in the condenser for servicing the compressor. 11. Plant Automation System Interface: The chiller shall be supplied with Bacnet and Modbus based HLI module which shall translate the information in the chiller microprocessor to an ASCII stream of data which can be read or written to by any manufacturer's chiller plant automation system. A suitable configured driver software to interface the chiller control unit to the CPA shall be provided by chiller manufacturer to enable CPA directly access to retrieved the data. M FACTORY PERFORMANCE TEST FOR CHILLERS Factory performance test shall be conducted for each typical chiller at the manufacturer s test facility. Factory witness performance testing shall be conducted for 4 points of loading at 25%, 50%, 75% and 100% of the full loading for each typical chiller. Performance testing shall be carried out to validate that the achieved efficiency at each loading condition shall be within the tolerance of the theoretical data based on the AHRI 550/590 conditions. 3 AUTOMATIC TUBE BRUSHING (ATB) SYSTEM 3.1 General: This section of the specification covers the supply, delivery, installation, testing and commissioning and warranty of automatic tube brush (ATB) type cleaning system. Any Automatic Tube Cleaning System that works by probability to clean the tubes shall not be accepted. Every condenser tube shall be assigned a cleaning brush unless the basket is obstructed The chiller supply shall supply ATB as a package and guarantee the performance. The ATB System shall install at all the water-cooled chillers indicated. The supplier shall include all the associated accessories to ensure the whole system is complete. The equipment shall be certified by Singapore Green Building Council (SGBC) or Singapore Environment Council (SEC).The chiller supplier shall supply the Automatic On-line Tube Cleaning System as a package and guarantee the performance. The System shall be installed at all the water-cooled chillers indicated. The supplier shall include all the associated accessories to ensure the whole system is complete. 3.2 Equipment: TS-CH-11

12 An Automatic Tube Brushing System shall be installed for each condenser/heat exchanger to maintain a fouling factor for all condenser tubes at or below hr sq ft Deg F/ BTU. The Automatic Tube Brushing System shall include the following: One brush and basket set (one brush/two baskets with two end clips) is to be furnished for each tube. Brushes are to be made of nylon bristles, with titanium wire and polypropylene tips. Each basket assembly consists of a cage and a removable locking end clip, having a minimum of four (4) prongs. The end clips can be removed and reinserted into the baskets without deformation to the basket. Basket is to be made of polypropylene. The baskets are to be directly fastened to the tube end using special epoxy and able to withstand a 10 pound pull test. The basket shall be designed so that, when attached to the tube, full access to the tube is provided by removing the end clip. This allows removal of the brush from the tube. Brush and Baskets sets shall be installed at site by trained technicians of the supplier. The top of the ATBS valve is to have a removable cover for easy access for service and maintenance. Valve shall be hydrostatic pressure tested to 1.5 times design working pressure or to 225 psig whichever is higher. The packing gland is to be stainless steel. The valve shall have a stainless steel seat at both Normal and Reverse position. Each valve shall be a 400V/3phase/50Hz electric actuator complete with gear and motor that turns the diverter valve with high torque. The electric actuator shall be equipped with torque, position limit, thermal switches and heaters. The electric actuator shall have a hand wheel to turn valve manually. The electric actuator shall have a minimum protection of IP67. The 4 way valve shaft and electric actuator shaft shall be connected by a heavy duty axially split rigid spacer type coupling to allow the packing gland of the 4 way valve to be fully accessible for removal and replacement with new packing without removal of electric actuator The primary function of each control panel is to provide signals to the ATBS valve actuator at preset time intervals. There shall be one control panel for each ATBS valve The Control Panel shall include: PLC or PLR to initiate cleaning cycle. Test Pushbutton to start brushing cycle. Push-button for Fault Light Indication Reset Power On Indicator Light ATBS Valve Position Indication Lights (Normal & Reverse) TS-CH-12

13 Cycle counter. Controls panel shall have at least IP 55 protection. Dry contacts for Power On, Normal Flow, Reverse Flow and Fault for BAS interface Remote Control and Monitor from BAS Mounting of control panel shall be close to ATB valve and chiller. 3.3 Equipment Warranty: The contractor is to guarantee all system components, except brushes to be free from defects in material and workmanship for period of 12 months from the date of completion. Brush life to be guaranteed for five (5) years from initial start up based on manufacturers recommended of a maximum of 4 cycles per 24 hours. 3.4 Performance Guarantee: When the system is installed and in operation in accordance with the instructions furnished by the manufacturer, the fouling factor for the tubes with brush and basket is to be maintained at or below hr sq ft Deg F/ BTU. Condenser water approach temperature being trend logged by BMS through High level Interface shall be monitored as the indication of clearness of the condenser tube. The condenser approach temperature shall not increase more than 1 o C each year. At anytime during two years defect liability period, if the condenser approach temperature exceed 2 C when chiller operating above 75% part load condition, chiller supplier shall carry out manual tube cleaning and/or descaling to bring down the approach temperature to below 1 C. In addition, verification of cleanliness of the condenser tubes for all chillers shall be performed before the end of 12 months defect liability period to verify that the tubes are cleaned. Verification of cleanliness shall be by manual brushing through the condenser tubes by a rotating brush. In addition, a videoscope shall be provided by the Automatic Tube Brush System Manufacturer for the verification. Still picture shots and video of the inside of the condenser tubes shall be provided. Hardcopies of still picture shots and soft copy of video of the inside of condenser tubes shall be provided and submitted to customer as well. The Owner or its representative shall randomly select 15% of tubes population to perform this verification by the Automatic Tube Brush System Manufacturer. 3.5 Installation: Prior to installing the brush and baskets, the condenser tubes shall be cleaned and brushed. The installation of brush and basket will be performed by the ATB manufacturer s qualified personnel on all condenser tubes that are not obstructed. TS-CH-13

14 3.6 Service and Maintenance: The Automatic Tube Brush System shall be serviced at least quarterly to check and verify the condenser tubes are clean. TS-CH-14