JOHNSON CONTROLS
19
SECTION 2 - PRODUCT DESCRIPTION
FORM 201.30-ICOM1 (519)
ISSUE DATE: 05/22/2019
2
SEMI-HERMETIC YORK SCREW
COMPRESSORS
The direct-drive, semi-hermetic rotary screw com-
pressor incorporates advanced technology in a rugged
design. The continuous function, microprocessor con-
trolled VSD provides smooth capacity control from
100% down to 20% chiller capacity. State-of-the-art
screw compressor design and manufacturing ensures
optimal efficiencies at all chiller load points. With no
unloading steps or slide valves in the compressor, the
YVWA variable speed driven compressor has 50%
fewer moving parts than fixed speed compressors
with slide valves. The YVWA compressor is one of
the most efficient and reliable screw compressors in
the industry.
EVAPORATOR
The evaporator is a shell and tube, hybrid falling film
type heat exchanger. It contains a balance of flooded
and falling film technology to optimize efficiency, min-
imize refrigerant charge, and maintain reliable control.
A specifically designed distribution system provides
uniform refrigerant flow for optimum performance.
CONDENSER
The condenser is a shell and tube type, with a dis-
charge gas baffle to prevent direct high velocity im-
pingement on the tubes. The baffle is also used to
distribute the refrigerant gas flow properly for the
most efficient heat transfer. An integral sub-cooler is
located at the bottom of the condenser shell provid-
ing highly effective liquid refrigerant subcooling to
provide the highest cycle efficiency .
REFRIGERANT CIRCUIT
The YVWA has one independent refrigerant circuit
per compressor. An electronic expansion valve (EEV),
controlled by the unit panel, accommodates varying
head and load conditions. The condenser shell is ca-
pable of storing the entire system refrigerant charge
during servicing. Optional service valves are available
to facilitate the removal of refrigerant. The sub-cooling
economizer (plate heat exchanger type), controlled by
the unit panel, meters some refrigerant gas to the com-
pressor to reduce energy consumption.
COMPLETE FACTORY PACKAGE
Each unit is shipped as a complete factory package,
completely assembled with all interconnecting refrig-
erant piping and internal wiring and ready for field
installation. Prior to shipment, each individual chiller
undergoes an extensive testing procedure, ensuring
workmanship is the highest quality and that the initial
start-up is trouble-free.
Before leaving the factory, each refrigerant circuit
is factory pressure tested, evacuated and then fully
charged with HFC-134a refrigerant and oil. An opera-
tional test is performed with water flowing through the
evaporator and condenser to ensure each circuit func-
tions correctly.
ELECTRICAL
All controls and motor starting equipment necessary
for unit operation are factory wired and function tested.
There are no surprises at start-up; the unit will start up
right the first time and every time. The standard unit
is equipped with circuit breaker for electrical connec-
tions. The chillers come with a single point power con-
nection and are supplied with a factory mounted and
wired control transformer that powers all unit controls
from the main unit power supply. The transformer uti-
lizes scheduled line voltage on the primary side and
provides 115V/1Ø on secondary. All exposed power
wiring is routed through liquid-tight, UV-stabilized,
non-metallic conduit.
VSD Power/Control Panel includes main power con-
nections, VSD contactors, current overloads, and fac-
tory wiring. All display and control features can be ac-
cessed through the keypad and control display access
door, eliminating the need to open the main cabinet
doors.
BUILDING AUTOMATION SYSTEM
CAPABILITIES
The E-Link Gateway provides an economical and ver-
satile connection between Johnson Controls equipment
and open/standard protocols. It efficiently manages the
communication protocols currently used by Johnson
Controls equipment, exposing the data in a consistent,
organized, and defined fashion. A simple switch selec-
tion allows configuration of the required equipment
profile and output protocol, which reduces equipment
connectivity startup time.
Summary of Contents for YVWA
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