Download 1 - Dependable Mechanical Systems Inc

Pre-purchase specification
November 2014
PART - 1
GENERAL
1.1
GENERAL
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 1
.1
This pre-purchase specification requests technical and financial offers for two factory
assembled and tested 300 ton capacity centrifugal water chillers that will be installed by
others as part of a comprehensive upgrade of the chilled water plant at the CAMH facility at
250 College St in Toronto.
.2
It is the specific goal of the CAMH to have the chiller plant operational by April 15, 2011 so
time is of essence in the manufacturing and delivery of the selected equipment.
.3
Selection of the successful vendor will be based on technical evaluation, ability to deliver to
suit project timeline and price.
.4
The pre-purchase contract shall be assigned to an installation contractor who shall be
selected through a tender process that will be completed after this vendor has been
selected.
1.2
INCLUSIONS
.1
Labour, products, equipment and services necessary to complete the work of this Section.
.2
Hoisting into place and installation is NOT included in this scope
.3
It is the intention of this project to complete the installation in an expeditious and contiguous
manner. To facilitate staging of construction and hoisting activities, the equipment
manufacturer shall allow for temporary storage of the units in or around Toronto and shall
arrange for shipment to the site precisely to suit hoisting activities.
1.3
REFERENCE STANDARDS
.1
NORR Limited
Comply with the latest edition of the following:
.1
CSA B51: for the construction, testing, approval and installation of boilers, pressure
vessels and all fittings installed in pressurized system.
.2
Technical Standards and Safety Authority - Pressure Vessels Safety Branch.
.3
CSA B52
.4
ASME Code, Section VIII
.5
AHRI STANDARD 550/590-2003 – Centrifugal water chillers. Unit shall bear the
AHRI Certification Label for the specific type of water chiller as applicable
.6
ANSI/ASHRAE STANDARD 15-2007 - Safety Code for Mechanical Refrigeration.
.7
NRC Measures for Energy Conservation in New Buildings
.8
CGSB - Canadian General Standards Board
.9
ASHRAE IES 90.1-1999
.10
ANSI/UL 465 - Central Cooling Air Conditioners.
.11
AHRI Standard 575-2008 Sound
.12
AFBMA 9 - Load Ratings and Fatigue Life of Roller Bearings.
.13
ASHRAE STANDARD 34 - Number Designation and Safety Classification of
Refrigerants
Project No. ECBL14-0213
Pre-purchase specification
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 2
November 2014
.14
1.4
ANSI/ASHRAE Standard 147-2002 - Reducing the Release of Halogenated
Refrigerants from Refrigerating and Air-Conditioning Equipment and Systems
ACCEPTABLE MANUFACTURERS:
.1
Trane
.2
Daiken/McQuay
.3
Carrier
.4
York
1.5
SUBMITTALS
.1
Shop Drawings
.1
NORR Limited
Submit shop drawings along with your tender submission. Shop drawings shall
include the following information:
.1
Model number, performance and design data, rigging dimensions,
assembled dimensions, operating weight, load distribution, and required
service and access clearances.
.2
Guaranteed rating and power input requirements. Submit product data
indicating options and specialties, electrical requirements, and wiring
diagrams and connections.
.3
Indicate accessories, valves, strainers, and thermostatic valves required
for the complete system.
.4
NPLV ratings
.5
Part load power ratings at constant condenser water temperature
.6
Part load power rating with prorated condenser water relief temperature
Submit performance data indicating energy input versus cooling load
output from 100 to 25 percent of full load with constant entering condenser
water temperature.
.7
Impeller speed, number of bearings, type of bearings, high speed impeller
shaft RPM, number of stages and inlet guide vanes, refrigerant and oil
charge weight
.8
Sound levels per ARI 575-94
.9
Evaporator and condenser heat transfer areas.
.10
Inlet and outlet connection details,
.11
Load and loading points, disassembled dimensions.
.12
Purge unit and refrigerant pump down unit showing physical sizes, piping
and wiring connections.
.13
Field assembly piping drawings, with chilled (and condenser) water flows,
connection pipe sizes, and pressure drops.
.14
Submit compressor and product data in table form indicating impeller
speed (RPM), number of bearings, type of bearings, high speed impeller
shaft RPM, sound pressure level per AHRI 575-1994 (dB), number of
stages, number of sets of inlet guide vanes, amount of refrigerant charge
(lb), and amount of oil required (gal).
Project No. ECBL14-0213
Pre-purchase specification
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 3
November 2014
1.6
.15
Variable speed drives and translineator
.16
Ladder logic style circuit diagrams showing starters, interlocks, and relays
with wire numbers and terminal numbers clearly identified.
OPERATION AND MAINTENANCE DATA
.1
Submit printed operating instructions and maintenance data for chiller, controls and speed
drive prior to delivery of equipment.
.2
Submit rigging, installation, and start up procedures prior to delivery of equipment for both
the chillers and variable-speed drives
.3
Detailed shop drawings indicating internal and external wiring with terminal numbers and
pertinent data. Submission of co-ordination curves on one common sheet of K & E TCC
graph paper showing
.4
1.7
.1
Motor damage curve.
.2
Motor heating characteristics.
.3
Overload relay characteristics.
.4
Circuit breaker characteristics.
Overload relay and circuit breaker to be shown at setting that will protect motor.
QUALITY ASSURANCE
.1
Performance Testing
.1
.2
.3
.4
Provide a factory performance test as follows:
.1
Test in accordance with ARI 550/590-98. Submit full details of testing
procedure prior to start of test.
.2
Demonstrate stable operation down to 25% load at constant design
condenser water temperature.
.3
Submit certified test report of all data. Pre-printed certification is not
acceptable.
Capacity Test Performance Penalty
.1
Deduct from purchase cost CDN $1000 /ton for each ton short of the
specification requirements.
.2
Specification rating modified by accepted tolerance as per Section 1.06 E
of ARI 550/590-98.
.3
Penalty applies to all same size chillers ordered, whether tested or not.
Power Consumption Penalty
.1
Deduct from purchase cost CDN $20,000/kw for each kW over the
allowable kW/ton of the specification requirements.
.2
Specification rating modified by accepted tolerance as per Section 1.06 E
of ARI 550/590-98.
.3
Penalty applies to all same size chillers ordered, whether tested or not.
Sound Data
.1
NORR Limited
The centrifugal chiller sound pressure Level (SPL), in decibels (dB), with a
Project No. ECBL14-0213
Pre-purchase specification
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 4
November 2014
reference pressure of 20 micropascals (µPa), shall not exceed Sound
Levels specified. All ratings shall be in accordance with AHRI Standard
575-2008.
.2
.5
TranLineator
.1
1.8
To represent the chiller's loudest operating condition and expose any
sound problems, a reduction in the temperature of the entering condenser
water and/or raising of the leaving chilled water temperature shall not be
allowed when determining the Sound Pressure Levels.
Submit for approval before shipment certified production test results or
translineator with serial numbers for harmonic mitigation performance and
energy efficiency under actual variable frequency drive loading.
MANUFACTURERS SERVICE
.1
Unit manufacturer shall provide the service of a qualified Field Engineer to supervise the
erection, wiring, evacuation and dehydration and charging of refrigerant and oil of the units.
.2
Upon completion of installation, submit written statement to the Consultant certifying that
alignment, wiring, piping connections, and controls have been installed correctly, sequence
of operation is correct and machine is ready for operation.
.3
Provide start-up and commissioning of the chillers and provide a comprehensive
commissioning report for inclusion into the operations and maintenance manual.
.4
Provide services of a manufacturer’s representative for an additional ten (10) hours to
instruct the Owner's personnel in the proper operation of unit. Include expenses of Field
Engineer in Tender Price.
.5
Chiller manufacturer to retain services of VFD manufacturer’s representative for supervision
of handling, installation and assembly and testing of electrical components.
1.9
WARRANTY
.1
Provide first year warranty for parts and labour for the entire unit including compressor and
refrigerant. Warranty shall start from acceptance of installation.
.2
Provide an additional 4 year warranty (for a total of 5 years) for parts and labour on the
compressor.
.3
The variable speed drive shall be warranted by the manufacturer for which ever comes first
between a period of 12 months from the date of installation, or 18 months after shipment.
PART - 2
PRODUCTS
2.1
GENERAL
.1
Refrigerant: HCFC-123 or HFC-134a
.2
Centrifugal liquid chilling package, consisting of compressor-motor unit, evaporator,
condenser, purge system, control console
.3
Factory assembled, insulated, tested and dehydrated at factory. Disassembled to facilitate
shipment and handling and reassembled in situ.
NORR Limited
Project No. ECBL14-0213
Pre-purchase specification
November 2014
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 5
.4
All condenser and chilled water connections shall be from one end. To facilitate chillers
operation in a side by side configuration, control panels shall be on opposite sides so that
panels will face inwards towards each other.
.5
Chillers shall be suitable for fully guarded operation and shall be exempt from the Operating
Engineer’s Act.
.6
Chillers shall be suitable to operate with 416v 3 phase 60 Hz power. If this criteria cannot
be met, provide a suitable step up transformer for each machine.
2.2
PERFORMANCE RATINGS
.1
Nominal 300 ton capacity.
.2
NPLV rating shall be maximum 0.46 kW/ton with maximum condenser water relief of
18.3°C (65°F)
.3
Efficiency at full load shall be maximum 0.67 kW/ton
.4
Evaporator and Condenser Tube ratings
.5
.6
.7
2.3
.1
Condenser and evaporator tubes maximum water velocity: 2.5 m/s [8 fps]
.2
Condenser water side fouling factor: 0.000044 m 2°C/W [0.00025 hr ft2°F/Btu]
.3
Evaporator water side fouling factor: 0.000018 m2°C/W [0.0001 hr ft2°F/Btu]
Pressure drop
.1
Evaporator maximum pressure drop 52 kPa [17 ft water gauge]
.2
Condenser maximum pressure drop 40 kPa [15 ft water gauge]
Operating temperatures
.1
Chilled water 5.55˚C to 11.1˚C [42˚F to 52˚F]
.2
Condenser water 29.4˚C to 35˚C [85˚F to 95˚F]
Dimensional Criteria
.1
All chilled water piping connections at one end. One condenser water connection
at both ends.
.2
Overall width of two units side by side plus recommended service clearances not to
exceed 18 ft.
.3
Overall unit length not to exceed 18 ft.
COMPRESSOR-MOTOR ASSEMBLY
.1
NORR Limited
Compressor
.1
Cast iron casing: divided to allow access to rotor assembly, and major wearing
parts are accessible for maintenance and replacement.
.2
Impeller(s): erosion and corrosion resistant to preserve initial impeller balance and
performance characteristics, statically and dynamically balanced to vibration levels
less than one mil at operating speed.
.3
Variable inlet guide vanes at inlet to each impeller on stainless steel shafts
complete with linkage assembly and pneumatic operator or operators.
.4
No-load start with variable inlet vane assembly
Project No. ECBL14-0213
Pre-purchase specification
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 6
November 2014
.5
.2
.3
.4
Lubrication System, Force Feed Type
.1
Lubrication oil force-fed to all bearings, gears and rotating surfaces by an oil pump
which operates prior to startup, continuously during operating and during
coastdown.
.2
Statically and dynamically balanced complete with pump, hermetic motor
.3
Oil filter, relief valve (if positive displacement pump is provided), pressure regulator,
and oil sightglass.
.4
Water-cooled shell-and-tube type oil cooler, electric immersion heater, all factoryinstalled with oil reservoir.
.5
Temperature and pressure gauge, two-stage thermostat for control of the electric
heating element and cooling water solenoid valve, shutdown switch, bearing
thermometer,
Motor
.1
Hermetically sealed, suction or liquid refrigerant cooled, squirrel cage induction
type compressor motor, or open type drive
.2
Open drive machines: shaft seal leakage containment system
.3
Motor speed: 3550 rpm
.4
Full load motor operation: not to exceed nameplate rating and the corresponding
recommended electrical power input
.5
Maximum starting current: 150% of current corresponding to nameplate rating
.6
Variable Frequency Drive
Refrigeration Transfer:
.1
.5
Factory install check or manual isolation valves in the compressor discharge line to
the condenser and the refrigerant liquid line leaving the condenser to allow for
isolation and storage of the full refrigerant charge in the chiller condenser shell. In
addition, provide isolation valve on the suction side of compressor from evaporator
to allow for isolation and storage of full refrigerant charge in the chiller evaporator
shell.
Sound Pressure Level
.1
NORR Limited
Provide service valves and other factory-installed accessories required to facilitate
transfer of refrigerant from the chiller to remote systems.
Refrigerant Isolation for chillers using 134a.
.1
.6
Modulation range: 20% to 100% without surge and with no condenser inlet
temperature reliefs.
Maximum sound pressure levels in decibels (dB) re. 20 micropascals to ARI 57594
Load %
Sound Pressure ( dBA )
100
82.5
50
80.5
25
81.5
Project No. ECBL14-0213
Pre-purchase specification
November 2014
2.4
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 7
EVAPORATOR AND CONDENSER
.1
.2
.3
Fabrication:
.1
Fabricated from heavy steel plate machine-welded to heavy steel tube sheets.
.2
Evaporator: shell and tube flooded type.
.3
Tubes: minimum 0.635 mm [0.025 inch] copper tube with integral fins on refrigerant
side, rolled into grooved holes in tube sheets
.4
Evaporator tubes: expanded into support sheets
Pressure rating:
.1
1035 kPa [150 psig] maximum working pressure
.2
Designed, constructed, tested and stamped in accordance with ASME code for
unfired pressure vessels.
Relief Devices and Discharge Piping
.1
.4
Multi-stage compressors
.1
.5
.6
.7
2.5
Pressure relief valves on both condenser and evaporator sections: to CSA B52.
Interstage flash vessel economizer
Single-stage compressors
.1
Condensers circuited for liquid sub-cooling
.2
Thermometer well to monitor level of sub-cooling
Shell Insulation
.1
Insulate evaporator shell and water boxes, and suction elbow.
.2
Thickness: 20 mm [¾"] closed cell elastomeric insulation.
Piping Insulation
.1
Economizer piping: 0.375 mm [3/8”] closed cell elastomeric insulation
.2
Motor cooling piping: 12 mm [½”] closed cell elastomeric insulation
VARIABLE SPEED DRIVE
.1
The centrifugal water chiller shall be furnished with an air cooled variable speed drive
(VSD). The VSD shall be remote or unit mounted and shipped completely factory
assembled, wired and tested.
.2
The VSD will be specifically designed to interface with the centrifugal water chiller controls
and allow for the operating ranges and specific characteristics of the chiller. The VSD
control logic shall optimize chiller efficiency by coordinating compressor motor speed and
compressor inlet guide vane position to maintain the chilled water setpoint while avoiding
surge. If a surge is detected, VSD surge avoidance logic will make adjustments to move
away from and avoid surge at similar conditions in the future.
.3
The VSD efficiency shall be 97% or better at full speed and full load.
displacement power factor shall be a minimum of 0.97.
NORR Limited
Fundamental
Project No. ECBL14-0213
Pre-purchase specification
November 2014
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 8
.4
The VSD shall be solid state, microprocessor based pulse-width modulated design. The
VSD shall be voltage and current regulated. Output power devices shall be IGBT
transistors.
.5
Power semi-conductor and capacitor cooling shall be from a liquid or air cooled heatsink.
.6
The VSDs shall each be furnished in a NEMA 1a sprinkler resistant metal enclosure having
as minimum a short circuit withstand rating of 65,000 amps per UL 508. It will include three
phase input lugs plus a grounding lug for electrical connections, output motor connection
via factory installed bus bars and all components properly segregated and completely
enclosed in a single metal enclosure.
.7
Enclosure shall include a padlockable, door-mounted circuit breaker with a minimum AIC
rating of 65,000 amps.
.8
The entire chiller package shall be ULC/UL listed.
.9
The VSD shall be tested to ANSI/UL Standard 508 and shall be listed by a Nationally
Recognized Testing Laboratory (NRTL) as designated by OSHA.
.10
Compliance to recommendations for harmonic mitigation.
.11
The VSD design shall include a DC link reactor on positive and negative rails to minimize
power line harmonics and protect the VSD from power line transients.
.12
Input shall be nominal 416 volts, three phase, 60 Hertz AC power, +/- 10 percent of nominal
voltage.
.13
Line frequency 38-60 hertz.
.14
The VSD shall include the following features:
.1
All control circuit voltages are physically and electrically isolated from power circuit
voltage.
.2
150% instantaneous torque available for improved surge control.
.3
Soft start, adjustable linear acceleration, coast-to-stop.
.4
Adjustable current limiting and UL approved electronic motor overload protection.
.5
Insensitivity to incoming power phase sequence.
.15
VSD and motor protection from the following faults: - Output line-to-line short circuit
protection - Line-to-ground short circuit protection - Phase loss at AFD input - Phase
reversal / Imbalance - Over-voltage - Under-voltage - Over temperature
.16
The following VSD status indicators shall be available to facilitate startup and maintenance:
- Output speed in hertz and rpm - Input line voltage - Input line kW - Output/load amps Average current in percent RLA - Load power factor - Fault - VSD transistor temperature
.17
Service Conditions -
.18
.1
Operating ambient temperature 14°F-104°F (-10°C-40°C).
.2
Room ambient up to 95% relative humidity.
.3
Elevation to 3300 feet (1000 meters).
Control and Auxiliary Power
.1
NORR Limited
Power source of 115 V, 1 phase, for chiller control panel and controls.
Project No. ECBL14-0213
Pre-purchase specification
November 2014
.19
2.6
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 9
.2
Separate transformer for Multilin system.
.3
Power supply to chiller oil pump, purge unit and oil heater.
.4
Flush mounted non-resettable counter on front of starter showing number of starts.
Acceptable Manufacturers
.1
Danfoss
.2
ABB
.3
GE
AUTOTANSLINEATOR
.1
The Variable Frequency Centrifugal Chiller Drives shall be equipped with AutoTranslineator
harmonic mitigation equipment to prevent power system problems resulting from high
levels of harmonic distortion. The AutoTranslineator and all of its components shall be
manufactured and tested in accordance with the latest applicable standards of UL, CSA
and NEMA. Demonstration of compatibility between the AutoTranslineator and the
Centrifugal Chiller VFD must be available upon request.
.2
The AutoTranslineator in combination with the Centrifugal Chiller Variable Frequency Drive
shall meet all requirements as outlined in the 1992 edition of IEEE std 519 for individual
and total harmonic voltage and current distortion. The Point of Common Coupling for all
voltage and current harmonic calculations and measurements shall be the input terminals
to the harmonic mitigation equipment.
.3
The characteristic harmonics shall be suppressed without the need for individual tuning or
the requirement to phase shift against other harmonic sources. Harmonic mitigation shall
be by passive inductor/capacitor network. Active electronic components shall not be used.
.4
The AutoTranslineator shall be warranted to be free of defects in materials and
workmanship for a period of 3 years from the date of shipment. Factory Performance
Testing:
.5
Manufacturer must be capable of factory testing for AutoTranslineator performance and
energy efficiency under actual variable frequency drive loads. A detailed description of the
program and a sample test report must be provided at time of quotation.
.6
Standard of acceptance: MIRUS International Inc. model ATL or approved equal
2.7
OPERATING CONTROL SYSTEM
.1
The chiller shall be controlled by a unit mounted, stand-alone Direct Digital Control (DDC)
system. A dedicated chiller microprocessor control panel is to be supplied with each chiller
by the chiller manufacturer.
.2
Enclosure shall be unit mounted NEMA 250 Type 1 using wire duct.
.3
A color, touch sensitive liquid crystal display (LCD) shall be unit mounted and a minimum of
12.1" diagonal. The display shall be fully adjustable in height and viewing angle. Animated
graphical representations of chiller subsystem operation shall be used to enhance the user
interface.
.4
Display shall consist of a menu driven interface with easy touch screen navigation to
organized subsystem reports for compressor, evaporator, condenser, purge and motor
information as well as associated diagnostics. The controller shall display all active
diagnostics and a minimum of 20 historical diagnostics.
NORR Limited
Project No. ECBL14-0213
Pre-purchase specification
November 2014
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 10
.5
The controller shall have the ability to display all primary sub-system operational
parameters on dedicated trending graphs. The operator must be able to create up to 6
additional custom trend graphs, choosing up to 10 unique parameters for each graph to
trend log data parameters simultaneously over an adjustable period and frequency polling.
.6
The chiller control panel shall provide control of chiller operation and monitoring of chiller
modules, sensors, actuators, relays and switches. The chiller control panel shall include
controls to safely and efficiently operate the Safeties - the chiller control panel shall provide
the following safeties:
.7
.1
Low chilled water temperature
.2
Low evaporator refrigerant temperature or pressure
.3
High condenser refrigerant pressure
.4
Evaporator and condenser water flow status
.5
Low oil pressure
.6
Low oil temperature
.7
High oil temperature
.8
High motor winding temperatures
.9
High motor current
.10
Starter/AFD function faults
.11
Sensor faults
.12
Unit controls operation
The chiller control panel or starter shall incorporate advanced motor protection to safeguard
the motor throughout the starting and running cycles from the adverse effects of:
.1
Current phase loss
.2
Current phase unbalance
.3
Current phase reversal
.4
Under/Over voltage
.5
Motor current overload
.6
Distribution fault protection with auto restart consisting of three-phase current
sensing devices that monitor the status of the current
.7
Starter contactor fault protection
.8
Starter transition failure
.8
The chiller control panel shall be capable of displaying system data in IP or SI units.
.9
The front of the chiller control panel shall display the following in clear language, without the
use of codes, look-up tables, or gauges:
NORR Limited
.1
Run time
.2
Number of starts
.3
Current chiller operating mode
.4
Chilled water set point and set point source
.5
Electrical current limit set point and set point source
Project No. ECBL14-0213
Pre-purchase specification
November 2014
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 11
.6
Entering and leaving evaporator water temperatures
.7
Entering and leaving condenser water temperatures
.8
Saturated evaporator and condenser refrigerant temperatures
.9
Evaporator and condenser refrigerant pressure
.10
Oil tank temperature
.11
Oil tank pressure
.12
Oil pump discharge pressure
.13
Differential oil pressure
.14
Compressor motor current per phase
.15
Compressor motor percent RLA
.16
Compressor motor voltage per phase
.17
kW energy consumption and power factor
.18
Compressor motor winding temperatures per phase
.19
Purge operating mode
.20
Purge operating status
.21
Time until next purge run
.22
Daily pump-out - 24 hours
.23
Avg daily pump-out - 7 Days
.24
Purge refrigerant compressor suction temp
.25
Purge liquid temp (chiller condenser saturated refrigerant temperature)
.26
Daily pump-out limit/alarm
.10
The chiller control panel shall provide password protection of all setpoints.
.11
Control authority must be capable of handling at least four conditions: Off, local manual at
the chiller, local automatic at the chiller and automatic control through a remote source.
.12
The chiller control panel shall provide evaporator freeze protection and low limit control to
avoid low evaporator refrigerant temperature trip-outs during critical periods of chiller
operation. Whenever this control is in effect, the controller shall indicate that the chiller is in
adaptive mode. If the condition exists for more than 30 seconds, a limit warning alarm relay
shall energize.
.13
The chiller control panel shall provide individual relay outputs to start/stop the evaporator
and condenser water pumps. The condenser water pump relay output can be used to
enable the cooling tower temperature controls.
.14
The chiller control panel shall provide leaving chilled water temperature reset based upon
return water temperature.
.15
The chiller control panel shall be capable of providing short cycling protection.
.16
Control voltage: 115 VAC, single phase
NORR Limited
Project No. ECBL14-0213
Pre-purchase specification
November 2014
.17
2.8
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 12
Building Management Interface:
.1
Integration network communication interface suitable
communication with Johnson Controls system in building
for
direct
serial
.2
Communications to include items specified under "Safety Permissives", "Operating
Control" and Panel HMI".
PURGE UNIT (LOW PRESSURE REFRIGERANT CHILLERS ONLY)
.1
2.9
Automatic, factory mounted, piped and wired, with single phase positive displacement
compressor with starter and purge drum.
.1
ARI Standard 580 listed
.2
Purge efficiency: maximum 0.00050 kg refrigerant/kg air lb refrigerant/lb air.
VIBRATION ISOLATORS
.1
2.10
Standard 10 mm [3/8"] thick neoprene pad vibration isolators for mounting between
concrete base and base of unit.
REFRIGERANT AND OIL
.1
2.11
Unit manufacturer to provide a complete charge of refrigerant and a complete charge of
lubricating oil. Furnish sufficient quantities of both for testing and purging of unit and a year
of normal compressor operation.
ACCESSORIES
.1
Thermometer wells: liquid refrigerant condensing and evaporating temperatures.
.2
Refrigerant and oil level sight glasses.
.3
Condenser water and evaporator water flow switches, each with a 3 second time delay
between flow collapse and switch activation.
.4
Pressure sensors for condenser and evaporator refrigerant pressure complete with panel
mounted dial gauges.
PART - 3
EXECUTION
3.1
MANUFACTURER'S FIELD SERVICES
.1
All start-up, maintenance and monitoring functions shall be performed by a manufacturer's
commercial agent to confirm, (in writing), that equipment has been correctly installed and
passes specification checklist prior to equipment becoming operational and covered under
OEM warranty.
.2
The manufacturer shall furnish complete submittal wiring diagrams of the chiller(s) starter(s)
and associated components like cooling towers, pumps, interlocks, etc. as applicable for
field maintenance and service.
3.2
SEQUENCE OF OPERATIONS
.1
General
.1
NORR Limited
The system shall be enabled to start in response to a binary contact signal from an
external source such as the building control system.
Project No. ECBL14-0213
Pre-purchase specification
23 64 16
CENTRIFUGAL WATER CHILLERS
Page 13
November 2014
3.3
CHILLER SEQUENCING SOFTWARE
.1
.2
Chiller Sequencing - The chiller sequencing software will start and stop system water
pumps and chillers based upon system load. When the chilled water system is enabled the
chiller system control will:
.1
Start the lead chiller after chilled water is proven.
.2
Start the lead chiller chilled water pump and prove flow through the evaporator.
.3
Start the system chilled water pump.
Chillers in Parallel
.1
.2
Starting Chillers - When the "chilled water error" value exceeds the specified limit
continuously for a operator specified length of time the chiller sequencing software
shall initiate the start of the next chiller in the sequence.
.1
Lag chillers shall start in a similar manner to the lead chiller start
sequence.
.2
The chiller sequencing software will unload operating chillers prior to
starting a lag chiller. This shall be done to prevent system water flow
disturbances caused by a lag chiller's pump starting from interrupting a
running chillers operation.
.3
The BAS shall control each chillers' setpoint to equalize the chiller loading
and meet system demands as the system load varies.
Stopping Chillers - When the "chilled water error" value exceeds the specified limit
continuously for a operator specified length of time the chiller sequencing software
shall initiate the shutdown of the next chiller in the sequence.
.1
3.4
The chiller sequencing software shall not shutdown the chiller pump until
all chiller compressors are proven off.
.3
Setpoint Control - The chiller sequencing software shall control individual chiller
setpoints to maintain the system supply water temperature at setpoint. The system
setpoint shall be 42 degrees F and editable by the operator. Alternately the system
setpoint shall be set by the chiller sequencing software reset program.
.4
Unload Before Start - Prior to the start of another chiller all operating chillers shall
be unloaded. This is done to prevent flow disturbances caused by the starting of
another pump from affecting chiller operation. Following confirmation of the
additional chiller operation all chillers shall be allowed to reload.
AUTOTRANSLINEATOR
.1
The AutoTranslineator shall be handled, stored and installed in accordance with the
manufacturer's recommended installation practices as found in the installation, operation,
and maintenance manual. Installation shall comply with all applicable codes.
.2
Harmonic compliance shall be verified with onsite field measurements of both the voltage
and current harmonic distortion at the input terminals of the harmonic mitigating equipment
with and without the equipment operating. A recording type Fluke 41 or equivalent
harmonics analyser displaying individual and total harmonic currents and voltages must be
utilized.
END OF SECTION
NORR Limited
Project No. ECBL14-0213