Specifications

36 YORK INTERNATIONAL
compressor load with quiet operation. Gears are inte-
grally assembled in the compressor rotor support and are
oil film lubricated. Each gear is individually mounted in
journal bearings with individual thrust bearings to insure
proper balance of forces from the impeller and motor.
LUBRICATION SYSTEM - YORK lubricating oil is force
fed to all bearings and filtered by an externally mounted
15 micron replaceable cartridge oil filter equipped with
service valves. An automatic oil recovery system returns
oil to the compressor that has migrated into the refriger-
ant system. Heat is removed from the oil by a refriger-
ant-cooled oil cooler, located in the evaporator. All oil
piping is completely factory-installed and tested. A ther-
mostatically controlled heater is supplied in the oil res-
ervoir to limit the amount of refrigerant absorbed by
the oil when the compressor is not operating.
Oil (under pressure) is supplied from the oil reservoir by
an internally-mounted submersible oil pump. Oil Pump
motors are available in 208 through 600V-3Ph-60/50Hz
to match the application and are supplied complete with
starter and current sensing overloads for extra protec-
tion. The oil reservoir heater is 1000 watts, 115V-1Ph-
60/50Hz immersion type. A separate three phase power
supply is required except when ordered with a YORK
Solid State Starter or Variable Speed Drive. A gravity
flow oil reservoir is provided to feed the bearings and
gears during coast down in the event of a power failure.
CAPACITY REDUCTION - Prerotation vanes (PRV)
modulate the unit capacity from 100% to 10% of design,
on normal air conditioning jobs. The prerotation vanes
are airfoil-shaped and made of manganese bronze. An
external, electric PRV operator automatically controls
the vane position through a simple, reliable linkage.
SHAFT SEAL - The compressor drive shaft seal con-
sists of a spring-loaded, precision lapped carbon ring,
high temperature elastomer “O” ring static seal, and
stress-relieved, precision lapped cast iron collar. The seal
features a small face area and low rubbing speed. It
provides an efficient seal under both vacuum and pres-
sure conditions. The seal is oil-flooded at all times and
is pressure-lubricated during compressor operation.
OPEN MOTOR - The 3600 RPM open motor is a drip-
proof, squirrel cage, induction type constructed to YORK
design specifications by nationally-known manufactur-
ers. Standard low voltage (208 through 600V-3Ph-60/
50Hz) motors are available for full-voltage (across-the-
line) or reduced-voltage (solid state, star delta or auto
transformer) starting. Standard high voltage (2300
through 4160V-3Ph60/50Hz) motors are available for full-
voltage (across-the-line) or reduced-voltage (primary re-
actor or auto transformer) starting. Open close coupled
motors are built with a cast iron adapter flanged be-
tween the motor and compressor. This unique design
allows the motor to be coupled to the compressor.
MOTOR TERMINAL BOX - The casing is fabricated of
heavy gauge steel. There are six terminals (three for
high voltage) in the terminal box. Provisions are fur-
nished for 208 through 600 volts for three-lead types of
starting (solid state, across-the-line, and auto trans-
former). Motor terminal lugs are furnished with the YORK
Current Guard Starter and the Variable Speed Drive
mounted in the power section. Overload/overcurrent
transformers (CT’s) are furnished as listed below; in
motor terminal box, as follows:
Application #CT’s Furnished in Motor Terminal Box
E-M STARTER 3
SS STARTER 0
VS DRIVE 0
COMPRESSOR LUBRICATION SYSTEM
The chiller lubrication system consists of the oil pump,
oil filter, oil cooler and all interconnecting oil piping and
passages. (See Fig. 22) There are seven main points
within the motor-compressor which must be supplied
with forced lubrication as follows:
1. Compressor Drive Shaft (Low Speed)
a. Shaft seal.
b. Front and rear journal bearings - one on each
side of driving gear.
c. Low speed thrust bearing (forward and reverse).
2. Compressor Driven Shaft (High Speed)
a. Forward and reverse high speed thrust bearing.
b. Three journal bearings (YDTJ67 through 95 and
YDTL108 through 126). Two journal bearings
(YDTL131 and 144).
3. Speed Increasing Gears
a. Meshing surfaces of drive and pinion gear teeth.
To provide the required amount of oil under the neces-
sary pressure to properly lubricate these parts, a motor
driven submersible oil pump is located in a remote oil sump.
Upon pressing of the “Compressor Start” switch on the
control center, the oil pump is immediately energized.
After a 30 second delay to allow the system oil pressure
to stabilize, the compressor motor will start. The oil pump
will continue to run during the entire operation of the
compressor, and for 150 seconds during compressor
coastdown.
The submerged oil pump takes suction from the sur-
rounding oil and discharges it to the oil cooler where
heat is rejected. The oil flows from the oil cooler to the
oil filter. The oil leaves the filter and flows to the emer-
gency oil reservoir where it is distributed to the
compressor bearings. The oil lubricates the compres-
sor rotating components and is returned to the oil sump.
Since the emergency oil reservoir is at the highest point
in the lubrication system, it provides an oil supply to