Guide Specifications - York STYLE A YCWS User Manual

Guide Specifications

YORK Model YCWS ______ Packaged Chiller(s). The
(each) unit shall have a cooling capacity of ______ tons
with Compressor kW when cooling GPM of water from
______ °F (°C) to ______ °F (°C) and with ____ GPM of
condensing water entering at ____ °F (°C) and leaving
at _____ °F (°C), and a cooler fouling factor of _____
and condenser water fouling factor of _____. The water
pressure drop shall not exceed ______ feet (kPa) of
water through the cooler and ______ feet (kPa) of water
through the condenser. The unit overall dimensions shall
not exceed _____feet (mm) _____ ins. in length, ______
feet (mm) _____ ins. in width and _____feet (mm) _____
in height. The unit operating weight shall not exceed
_____ lbs. (Kg).
GENERAL
The (Each) Packaged Water Cooled Screw Chiller shall
be completely factory assembled (in an ISO 9001 regis-
tered facility) including all interconnecting refrigerant pip-
ing and internal wiring of controls, mounted on a steel
base which accommodates
compressor(s) and evaporator. Operating test shall in-
clude operation with water flowing through the evapora-
tor.
Unit shall be painted with Caribbean Blue enamel. The
unit shall be shipped with a full operating charge of R-
22. The unit shall contain two separate refrigerant cir-
cuits, each with a single compressor for standby opera-
tion. All units shall be designed and constructed in ac-
cordance with the applicable sections of the following:
American Society of Heating, Refrigeration and Air Con-
ditioning Engineers ANSI/ASHRAE 15 Safety Code for
Mechanical Refrigeration: American Society of Mechani-
cal Engineers ASME Pressure Vessel Code; National
Electrical Code/National Fire Protection Association
NFPA 70. The unit shall be produced at an ISO 9001
registered facility. All chillers are rated in accordance
with ARI Standard 550/590.
COMPRESSORS
Compressors shall be direct drive, semi-hermetic, ro-
tary twin-screw type, including: internal muffler, tempera-
ture actuated ‚off-cycle heater, terminal box, internal dis-
charge check, discharge and suction shutoff service
valves, and precision machined cast iron housing. De-
sign working pressure of entire compressor, suction to
discharge, shall be 31 bar (450psig).
Motors shall feature refrigerant suction-gas cooled two-
pole accessible hermetic compressor motor, full suction
gas flow through a mesh screen, with inherent internal
thermal overload protection and external current over-
load on all three phases. Motor stator shall employ
YORK INTERNATIONAL
APT2000 type magnet wire.
Lubrication shall feature external oil separators with no
moving or fragile parts, 31 bar (450psig) design working
pressure, and UL listing. Refrigerant system differential
pressure shall provide oil flow through service replace-
able, 0.5 micron, full flow, cartridge type oil filter internal
to compressor. Filter bypass, less restrictive media, or
oil pump not acceptable.
Compressors shall start at minimum load position. Ca-
pacity control range from 100% to 10% of chiller full load
using continuous function slide valves, and without hot
gas bypass. Step unloading unacceptable. Provide Mi-
croprocessor controlled, output pressure regulating ca-
pacity control valve to command compressor capacity
independent of control valve input pressure and balance
compressor capacity with cooling load.
CAPACITY CONTROL SYSTEM
the condenser,
Continuous function, microprocessor controlled, 3- way
proportional Capacity Control Valve provides regulated
output pressure independent of valve input pressure for
a stable, smooth, and precise match of compressor ca-
pacity to cooling load to 10% of chiller capacity.
COOLER
The cooler shall be a direct expansion shell and tube
type with refrigerant in the tubes and liquid to be chilled
in the shell. The design working pressure of the cooler
shell (liquid) side shall be 150 PSIG for the tube (refrig-
erant) side. Refrigerant heads shall be removable. The
cooler shall be covered with 3/4" flexible closed cell foam
insulation (K = 0.25 maximum) to prevent sweating. The
cooler shall be constructed and tested in accordance
with ASME Code requirements. Vent and drain connec-
tions shall be included. The water connections shall be
fully accessible and grooved to accept victaulic couplings
if used (by others).
CONDENSER
The condenser is a cleanable thru-tube with steel shell,
copper tubes, removable water heads and includes in-
tegral subcooling. Refer to PHYSICAL DATA for design
working pressures. The shell will be constructed and
tested in accordance with section VlII, division 1 of ASME
pressure-vessel code. The condenser is equipped with
relief valves and will hold the full refrigerant charge for
pumpdown.
REFRIGERANT CIRCUITS
Two independent refrigerant circuits will be furnished on
FORM 201.24-EG1
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