Guide Specifications - York R-407C Optimized Manual

Air cooled screw liquid chillers
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Guide Specifications

PART 1 — GENERAL
1.01
SCOPE
A. The requirements of the General Conditions, Supple-
mentary Conditions, Division 1, and Drawings apply
to all Work herein.
B. Provide Microprocessor controlled, twin-screw com-
pressor, air-cooled, liquid chillers of the scheduled
capacities as shown and indicated on the Drawings,
including but not limited to:
1. Chiller package
2. Charge of refrigerant and oil
3. Electrical power and control connections
4. Chilled water connections
1.02
QUALITY ASSURANCE
A. Products shall be Designed, Tested, Rated and Cer-
tified in accordance with, and installed in compliance
with applicable sections of the following Standards
and Codes:
1. ANSI/ASHRAE Standard 15 – Safety Code for
Me-
chanical Refrigeration
2. ANSI/NFPA Standard 70 – National Electrical
Code
3. ASME Boiler and Pressure Vessel Code, Section
VIII, Division 1.
4. ARI Standard 550/590 – Centrifugal and Rotary
Screw Water Chilling Packages.
5. Conform to Underwriters Laboratories (U.L.) for
construction of chillers and provide U.L./cU.L.
List
ing label.
6. Manufactured in facility registered to ISO 9002.
B. Factory Test: Chiller shall be pressure-tested, evac-
uated and fully charged with refrigerant and oil, and
shall be factory operational run tested with water
flowing through the vessel.
C. Warranty: Manufacturer shall Warrant all equipment
and material of its manufacture against defects in
workmanship and material for a period of eighteen
(18) months from date of initial start-up or date of
shipment, whichever occurs first.
1.03
DELIVERY AND HANDLING
A. Unit shall be delivered to job site fully assembled,
and charged with refrigerant and oil by the Manu-
facturer.
B. Unit shall be stored and handled per Manufacturer's
instructions.
PART 2 — PRODUCTS
2.01
CHILLER MATERIALS AND COMPONENTS
A. General: Install and commission, as shown on the
YORK INTERNATIONAL
(N.E.C.).
schedules and plans, factory assembled, charged,
and tested air cooled screw compressor chiller(s) as
specified herein. Chiller shall be designed, selected,
and constructed using a refrigerant with Flammability
rating of "1", as defined by ANSI/ASHRAE STAN-
DARD-34 Number Designation and Safety Classi-
fication of Refrigerants. Chiller shall include, but is not
limited to: a complete system with not less than two
independent refrigerant circuits, semihermetic twin
screw compressors, direct expansion type evapo-
rator, air-cooled condenser, refrigerant, lubrication
system, interconnecting wiring, safety and operating
controls including capacity controller, control center,
motor starting components, and special features as
specified herein or required for safe, automatic op-
eration.
B. Cabinet: External structural members shall be con-
structed of heavy gauge, galvanized steel coated with
baked on powder paint which, when subject to ASTM
B117, 500 hour, 5% salt spray test, yields minimum
ASTM 1654 rating of "6".
2.02
COMPRESSORS AND MOTORS
A. Compressors: Shall be direct drive, semihermetic,
rotary twin-screw type, including: internal muffler,
temperature actuated 'off-cycle' heater, rain-tight ter-
minal box, internal discharge check, discharge and
suction shut-off service valves, and precision ma-
chined cast iron housing. Design working pressure of
entire compressor, suction to discharge, shall be 450
PSIG (31 Bar). Compressor shall be U.L. listed.
B. Motors: Refrigerant suction gas cooled two-pole
accessible hermetic compressor motor, full suction
gas flow through 0.006" maximum mesh screen, with
inherent internal thermal overload protection and ex-
ternal current overload on all three phases. Motor
stator shall employ APT2000 type magnet wire.
C. Lubrication: External oil separators with no moving or
fragile parts, 450 PSIG design working pressure, and
U.L. listing. Refrigerant system differential pressure
shall provide oil flow through service replaceable,
0.5 micron, full flow, cartridge type oil filter internal
to compressor. Filter bypass, less restrictive media,
or oil pump not acceptable.
D. Capacity Control: Compressors shall start at minimum
load position. Capacity control range from 100% to
10% of chiller full load using continuous function slide
valves, and without hot gas bypass. Step unloading
unacceptable. Provide Microprocessor controlled,
output pressure regulating capacity control valve to
command compressor capacity independent of con-
trol valve input pressure and balance compressor
capacity with cooling load.
FORM 201.19-EG4
113

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