FORM 160.81-O1 (1020)
ISSUE DATE 10/05/2020
11
JOHNSON CONTROLS
SECTION 1 - DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION
1
In operation, a liquid (water or brine to be chilled) flows
through the cooler, where boiling refrigerant absorbs
heat from the liquid. The chilled liquid is then piped to
fan coil units or other air conditioning terminal units,
where it flows through finned coils, absorbing heat
from the air. The warmed liquid is then returned to the
chiller to complete the chilled liquid circuit.
The refrigerant vapor, which is produced by the boiling
action in the cooler, flows to the compressor where ro-
tary screw action compresses it increasing its pressure
and temperature and discharges it into the Oil Separa-
tor section which removes the oil before the high pres-
sure gas flows into the condenser tube bundle. Water
flowing through the condenser tubes absorbs heat from
the refrigerant vapor, causing it to condense. The con-
denser water is supplied to the chiller from an external
source, usually a cooling tower. The condensed refrig-
erant drains from the condenser into the liquid return
line, where the Variable Orifice meters the flow of liq-
uid refrigerant to the cooler to complete the refrigerant
circuit.
SYSTEM OPERATION DESCRIPTION
The YORK Model YR Chiller is applied to large air con-
ditioning systems, but may be used on other applications.
The chiller consists of a hermetic motor connected to a
rotary screw compressor, an Oil Separator, a condenser, a
cooler and an OptiView™ Control Center.
The chiller is controlled by a modern state of the art
Graphic Control Center that monitors its operation. The
Control Center is programmed by the operator to suit job
specifications. Automatic timed start-ups and shutdowns
are also programmable to suit nighttime, weekends, and
holidays. The operating status, temperatures, pressures,
and other information pertinent to operation of the chiller
are automatically displayed and read on a graphic dis-
play. Other displays can be observed by pressing the keys
as labeled on the Control Center. The chiller with the Op-
tiView™ Control Center is applied with an Electro-Me-
chanical Starter, or YORK Solid State Starter (optional).
FIGURE 1 -
MODEL YR CHILLER
00562VIP
CONTROL
CENTER
OIL
SEPARATOR
SIGHT GLASS
CONDENSER
VARIABLE
ORIFICE
SOLID STATE
STARTER
SECTION 1 - DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION