Johnson Controls YORK YK Style G OPTIVIEW Installation guide

MODEL YK (STYLE G)
R-134a
WITH OPTIVIEWTM CONTROL CENTER
FOR ELECTRO-MECHANICAL STARTER,
SOLID STATE STARTER AND VARIABLE SPEED DRIVE
CENTRIFUGAL LIQUID CHILLERS
OPERATIONS AND MAINTENANCE Supersedes: 160.75-O1 (508) Form 160.75-O1 (211)
LD15222

FORM 160.75-O1 (211)
JOHNSON CONTROLS
2
This equipment is a relatively complicated apparatus.
During installation, operation maintenance or service,
individuals may be exposed to certain components or
conditions including, but not limited to: refrigerants,
materials under pressure, rotating components, and
both high and low voltage. Each of these items has the
potential, if misused or handled improperly, to cause
bodily injury or death. It is the obligation and respon-
sibility of operating/service personnel to identify and
recognize these inherent hazards, protect themselves,
and proceed safely in completing their tasks. Failure
to comply with any of these requirements could result
in serious damage to the equipment and the property in
IMPORTANT!
READ BEFORE PROCEEDING!
GENERAL SAFETY GUIDELINES
which it is situated, as well as severe personal injury or
death to themselves and people at the site.
This document is intended for use by owner-authorized
operating/service personnel. It is expected that this in-
dividual posseses independent training that will enable
them to perform their assigned tasks properly and safe-
ly. It is essential that, prior to performing any task on
this equipment, this individual shall have read and un-
derstood this document and any referenced materials.
This individual shall also be familiar with and comply
with all applicable governmental standards and regula-
tions pertaining to the task in question.
SAFETY SYMBOLS
The following symbols are used in this document to alert the reader to specific situations:
Indicates a possible hazardous situation
which will result in death or serious injury
if proper care is not taken.
Indicates a potentially hazardous situa-
tion which will result in possible injuries
or damage to equipment if proper care is
not taken.
Identies a hazard which could lead to
damage to the machine, damage to other
equipment and/or environmental pollu-
tion if proper care is not taken or instruc-
tions and are not followed.
Highlights additional information useful
to the technician in completing the work
being performed properly.
External wiring, unless specied as an optional connection in the manufacturer’s product line, is
not to be connected inside the OptiView cabinet. Devices such as relays, switches, transducers and
controls and any external wiring must not be installed inside the micro panel. All wiring must be in
accordance with Johnson Controls’ published specications and must be performed only by a qualied
electrician. Johnson Controls will NOT be responsible for damage/problems resulting from improper
connections to the controls or application of improper control signals. Failure to follow this warning
will void the manufacturer’s warranty and cause serious damage to property or personal injury.

JOHNSON CONTROLS 3
FORM 160.75-O1 (211)
CHANGEABILITY OF THIS DOCUMENT
In complying with Johnson Controls’ policy for contin-
uous product improvement, the information contained
in this document is subject to change without notice.
While Johnson Controls makes no commitment to up-
date or provide current information automatically to
the manual owner, that information, if applicable, can
be obtained by contacting the nearest Johnson Controls
Service office.
Operating/service personnel maintains the responsi-
bility of the applicability of these documents to the
competitive equipment the kit is installed on. If there
is any question regarding the applicability of these
documents, the technician should verify whether the
equipment has been modified and if current literature
is available with the owner of the equipment prior to
performing any work on the chiller.
ASSOCIATED LITERATURE
MANUAL DESCRIPTION FORM NUMBER
Variable Speed Drive – Operation 160.00-O1
Solid State Starter – Operation and Maintenance 160.00-O2
Floor Mounted MV SSS – Operation 160.00-O5
Unit Mounted MV SSS – Operation 160.00-O7
Installation – Unit 160.75-N1
Optiview™ Control Center – Operation and Maintenance 160.54-O1
Wiring Diagram – Field Connections for YK Chiller (Style G) OptiView Control Center with Remote Low
or Medium Voltage EMS or Unit Mounted Low or Medium Voltage SSS 160.75-PW1
Wiring Diagram – Field Connections for YK Chiller (Style G) OptiView Control Center with Remote
Medium Voltage SSS 160.75-PW2
Wiring Diagram – Field Connections for YK Chiller (Style G) OptiView Control Center with Remote
Medium Voltage VSD 160.75-PW3
Wiring Diagram – Field Control Modications for YK Chiller (Style G) 160.75-PW4
Wiring Diagram – YK Chiller (Style G) OptiView Control Center with Remote Low or Medium Voltage EMS 160.75-PW5
Wiring Diagram – YK Chiller (Style G) OptiView Control Center with Unit Mounted Low or Medium
Voltage SSS, Unit Mounted Low Voltage VSD with Modbus, or Remote Medium Voltage VSD 160.75-PW6
Wiring Diagram – YK Chiller (Style G) OptiView Control Center with LTC I/O Board with Remote Low or
Medium Voltage EMS 160.75-PW7
Wiring Diagram – YK Chiller (Style G) OptiView Control Center w/ LTC I/O Board with Unit Mounted Low
or Medium Voltage SSS, Unit Mounted Low Voltage VSD with Modbus or Remote Medium Voltage VSD 160.75-PW8
Renewal Parts – Unit 160.75-RP1
Renewal Parts – OptiView Control Center 160.54-RP1

FORM 160.75-O1 (211)
JOHNSON CONTROLS
4
NOMENCLATURE
YK KC K4 H9 – CY G
MOTOR CODE
POWER SUPPLY
– for 60 Hz
5 for 50 Hz
COMPRESSOR CODE*
CONDENSER CODE*
EVAPORATOR CODE*
MODEL*
STYLE (Design Level)
* Refer to YK Engineering Guide for (Form 160.75-EG1)
Shell/Motor/Compressor combinations.

JOHNSON CONTROLS 5
FORM 160.75-O1 (211)
TABLE OF CONTENTS
SECTION 1 - DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION ..........................................7
System Operation Description .........................................................................................................................7
Capacity Control...............................................................................................................................................8
SECTION 2 - SYSTEM OPERATING PROCEDURES ........................................................................................... 11
Oil Heaters ..................................................................................................................................................... 11
Oil Heater Operation ...................................................................................................................................... 11
Checking The Oil Level In The Oil Reservoir ................................................................................................. 11
Start-Up Procedure ........................................................................................................................................ 11
Start-Up .......................................................................................................................................................... 11
Chiller Operation ............................................................................................................................................13
Condenser Water Temperature Control..........................................................................................................13
Operating Log Sheet ......................................................................................................................................13
Operating Inspections ....................................................................................................................................13
Need For Maintenance Or Service.................................................................................................................15
Stopping The System .....................................................................................................................................15
Prolonged Shutdown ......................................................................................................................................15
SECTION 3 - SYSTEM COMPONENTS DESCRIPTION .......................................................................................17
General...........................................................................................................................................................17
Compressor....................................................................................................................................................17
Capacity Control.............................................................................................................................................17
Compressor Lubrication System ...................................................................................................................17
Oil Pump.........................................................................................................................................................17
Oil Heater .......................................................................................................................................................21
Motor Driveline ...............................................................................................................................................21
Heat Exchangers............................................................................................................................................21
Refrigerant Flow Control ................................................................................................................................22
Optional Service Isolation Valves ...................................................................................................................22
Optional Hot Gas Bypass ...............................................................................................................................22
OptiView Control Center.................................................................................................................................22
Solid State Starter (Optional) .........................................................................................................................22
Variable Speed Drive (Optional).....................................................................................................................22
SECTION 4 - OPERATIONAL MAINTENANCE.....................................................................................................23
Oil Return System ..........................................................................................................................................23
Changing The Dehydrator ..............................................................................................................................23
The Oil Charge ...............................................................................................................................................24
Oil Charging Procedure..................................................................................................................................24
SECTION 5 - TROUBLESHOOTING......................................................................................................................25
SECTION 6 - MAINTENANCE................................................................................................................................27
Renewal Parts ................................................................................................................................................27
Checking System For Leaks ..........................................................................................................................27
Conducting R-22 Pressure Test......................................................................................................................27
Vacuum Testing ..............................................................................................................................................28
Vacuum Dehydration ......................................................................................................................................29
Operation........................................................................................................................................................29
Refrigerant Charging ......................................................................................................................................29
Checking The Refrigerant Charge During Unit Shutdown..............................................................................30
Handling Refrigerant For Dismantling And Repairs........................................................................................30

FORM 160.75-O1 (211)
JOHNSON CONTROLS
6
LIST OF FIGURES
LIST OF TABLES
FIGURE 1 - Model YK Chiller ....................................................................................................................................7
FIGURE 2 - Compressor Prerotation Vanes..............................................................................................................8
FIGURE 3 - Refrigerant Flow-Thru Chiller (Falling Film Evaporator) ........................................................................9
FIGURE 4 - Refrigerant Flow-Thru Chiller (Flooded Evaporator)............................................................................10
FIGURE 5 - Oil Level Indicator ............................................................................................................................... 11
FIGURE 6 - Chiller Starting Sequence And Shutdown Sequence (Em Starter And Solid State Starter) ................12
FIGURE 7 - Chiller Starting Sequence And Shutdown Sequence (Variable Speed Drive) .....................................12
FIGURE 8 - Liquid Chiller Log Sheets.....................................................................................................................14
FIGURE 9 - System Components Front View .........................................................................................................18
FIGURE 10 - System Components Rear View........................................................................................................19
FIGURE 11 - Schematic Drawing – (YK) Compressor Lubrication System............................................................. 20
FIGURE 12 - Oil Return System..............................................................................................................................23
FIGURE 13 - Charging Oil Reservoir With Oil.........................................................................................................24
FIGURE 14 - Evacuation Of Chiller.........................................................................................................................27
FIGURE 15 - Saturation Curve................................................................................................................................29
FIGURE 16 - Diagram, Megging Motor Windings ...................................................................................................30
FIGURE 17 - Motor Starter Temperature And Insulation Resistances ....................................................................31
Megging The Motor .........................................................................................................................................30
Compressor....................................................................................................................................................33
Electrical Controls ..........................................................................................................................................34
SECTION 7 - PREVENTIVE MAINTENANCE........................................................................................................35
Compressor....................................................................................................................................................35
Compressor Motor..........................................................................................................................................35
Greased Bearings .........................................................................................................................................35
Leak Testing ...................................................................................................................................................36
Evaporator And Condenser ............................................................................................................................36
Oil Return System ..........................................................................................................................................36
Electrical Controls ..........................................................................................................................................36
TABLE OF CONTENTS (CONT'D)
TABLE 1 - Operation Analysis Chart.......................................................................................................................25
TABLE 2 - System Pressures .................................................................................................................................28
TABLE 3 - Bearing Lubrication................................................................................................................................35

JOHNSON CONTROLS 7
FORM 160.75-O1 (211)
nent to operation of the chiller are automatically dis-
played and read on a graphic display. Other displays
can be observed by pressing the keys as labeled on the
Control Center. The chiller with the OptiView Control
Center is compatible with an electro-mechanical start-
er, YORK Solid State Starter (optional), or Variable
Speed Drive (optional).
In operation, a liquid (water or brine to be chilled)
flows through the evaporator, 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.
SECTION 1 - DESCRIPTION OF SYSTEM AND
FUNDAMENTALS OF OPERATION
SYSTEM OPERATION DESCRIPTION
The YORK Model YK Chiller is commonly applied
to large air conditioning systems, but may be used
on other applications. The chiller consists of an open
motor mounted to a compressor (with integral speed
increasing gears), condenser, evaporator and variable
flow control.
The chiller is controlled by a modern state of the art
Microcomputer Control Center that monitors its opera-
tion. The Control Center is programmed by the opera-
tor to suit job specifications. Automatic timed start-ups
and shutdowns are also programmable to suit night-
time, weekends, and holidays. The operating status,
temperatures, pressures, and other information perti-
1
LD15222
CONDENSER
CONTROL
CENTER
COMPRESSOR
MOTOR
EVAPORATOR
FIGURE 1 - MODEL YK CHILLER

FORM 160.75-O1 (211)
JOHNSON CONTROLS
8
SECTION 1 - DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION
7619A(D)
FIGURE 2 - COMPRESSOR PREROTATION VANES
The refrigerant vapor, which is produced by the boil-
ing action in the evaporator, flows to the compressor
where the rotating impeller increases its pressure and
temperature and discharges it into the condenser. Wa-
ter flowing through the condenser tubes absorbs heat
from the refrigerant vapor, causing it to condense. The
condenser water is supplied to the chiller from an ex-
ternal source, usually a cooling tower. The condensed
refrigerant drains from the condenser into the liquid
return line, where the variable orifice meters the flow
of liquid refrigerant to the evaporator to complete the
refrigerant circuit.
The major components of a chiller are selected to han-
dle the refrigerant, which would be evaporated at full
load design conditions. However, most systems will be
called upon to deliver full load capacity for only a rela-
tively small part of the time the unit is in operation.
CAPACITY CONTROL
The major components of a chiller are selected for full
load capacities, therefore capacity must be controlled
to maintain a constant chilled liquid temperature leav-
ing the evaporator. Prerotation vanes (PRV), located at
the entrance to the compressor impeller, compensate
for variation in load (Refer to Figure 2 on Page 8).
The position of these vanes is automatically controlled
through a lever arm attached to an electric motor lo-
cated outside the compressor housing. The automatic
adjustment of the vane position in effect provides the
performance of many different compressors to match
various load conditions from full load with vanes wide
open to minimum load with vanes completely closed.

SECTION 1 - DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION
JOHNSON CONTROLS 9
FORM 160.75-O1 (211)
1
Refrigerant Flow-Thru Chiller
(Falling Film Evaporator)
FIGURE 3 - REFRIGERANT FLOW-THRU CHILLER (FALLING FILM EVAPORATOR)
Rev. 2 (10-11-2010)
Dan Sowers
[e-mail]
[phone]
YK Mod G
Refrigerant Flow-Thru Cross-Secon Diagram
(Falling-Film Evaporator)
COMPRESSOR
EVAPORATOR
DISCHARGE
PRE-ROTATION
VANES
SUCTION
BAFFLE
SUB-COOLER
LIQUID LEVEL
CONDENSER
LIQUID LEVEL
VALVE
HOT GAS
BYPASS VALVE
LIQUID LEVEL
SUCTION
OPTIONAL
ISOLATION
VALVE
OPTIONAL
ISOLATION
VALVE
OPTIONAL HOT GAS
BYPASS LINE
LD00924A

FORM 160.75-O1 (211)
JOHNSON CONTROLS
10
SECTION 1 - DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION
Refrigerant Flow-Thru Chiller
(Flooded Evaporator)
FIGURE 4 - REFRIGERANT FLOW-THRU CHILLER (FLOODED EVAPORATOR)
Rev. 2 (12-09-2010)
Dan Sowers
[e-mail]
[phone]
YK Mod G
Refrigerant Flow-Thru Cross-Secon Diagram
(Flooded Evaporator)
COMPRESSOR
EVAPORATOR
DISCHARGE
PRE-ROTATION
VANES
MESH ELIMINATORS or
SUCTION BAFFLE
SUB-COOLER
LIQUID LEVEL
CONDENSER
SUCTION
LIQUID LEVEL
VALVE
LIQUID LEVEL
OPTIONAL
ISOLATION
VALVE
OPTIONAL
ISOLATION
VALVE
HOT GAS
BYPASS VALVE
OPTIONAL HOT GAS
BYPASS LINE
LD00924B

JOHNSON CONTROLS 11
FORM 160.75-O1 (211)
• If the oil level during operation is in the OVER
FULL region of the oil level indicator, oil should
be removed from the oil reservoir, This reduces
the oil level to the OPERATING RANGE.
• If the oil level during operation is in the LOW
OIL region of the oil level indicator, oil should be
added to the oil reservoir. (Refer to Oil Charging
Procedure on Page 24.)
Comply with EPA and local regulations
when removing or disposing of refrigera-
tion system oil!
START-UP PROCEDURE
Pre-Starting
Prior to starting the chiller, observe the Optiview™
Control Center – Operation and Maintenance (Form
160.54-O1). Make sure the display reads SYSTEM
READY TO START.
Vent any air from the chiller waterboxes
prior to starting the water pumps. Failure
to do so will result in pass bafe damage.
START-UP
1. If the chilled water pump is manually operated,
start the pump. The Control Center will not al-
lowthechillertostartunlesschilledliquidowis
established through the unit. If the chilled liquid
pump is wired to the Microcomputer Control Cen-
ter the pump will automatically start, therefore,
this step is not necessary.
2. To start the chiller, press the COMPRESSOR
START switch. This switch will automatically
spring return to the RUN position. (If the unit
was previously started, press the STOP/RESET
side of the COMPRESSOR switch and then press
the START side of the switch to start the chill-
er.) When the start switch is energized, the Con-
trol Center is placed in an operating mode and
any malfunction will be noted by messages on a
graphic display.
SECTION 2 - SYSTEM OPERATING PROCEDURES
OIL HEATERS
If the oil heater is de-energized during a shutdown pe-
riod, it must be energized for 12 hours prior to starting
compressor, or remove all oil and recharge compres-
sor with new oil. (Refer to Oil Charging Procedure on
Page 24.)
OIL HEATER OPERATION
The oil heater operation is controlled by the OptiV-
iew™ Control Center. The heater is turned on and off
to maintain the oil temperature differential to a value
50°F (27.8°C) above the condenser saturation tem-
perature. This target value is maintained by the control
panel.
If the target value is greater than 160°F (71°C), the tar-
get defaults to 160°F (71°C). If the target value is less
than 110°F (43.3°C), it defaults to 110°F (43.3°C).
To prevent overheating of the oil in the event of a con-
trol center component failure, the oil heater thermostat
(1HTR) is set to open at 180°F (82°C).
CHECKING THE OIL LEVEL IN THE
OIL RESERVOIR
Proper operating oil level – During operation, the oil
level should fall to the OPERATING RANGE identified
on the vertical oil level indicator label (Refer to Figure 5
on Page 11).
FIGURE 5 - OIL LEVEL INDICATOR
LD08647
2

FORM 160.75-O1 (211)
JOHNSON CONTROLS
12
SECTION 2 - SYSTEM OPERATING PROCEDURES
LD15609
FIGURE 6 - CHILLER STARTING SEQUENCE AND SHUTDOWN SEQUENCE (EM STARTER AND SOLID
STATE STARTER)
** Not for all shutdowns. Refer to “Display Messages” in manual Optiview™ Control Center – Operation and Maintenance (Form 160.54-O1).
FIGURE 7 - CHILLER STARTING SEQUENCE AND SHUTDOWN SEQUENCE (VARIABLE SPEED DRIVE)
** Not for all shutdowns. Refer to “Display Messages” in manual Optiview™ Control Center – Operation and Maintenance (Form 160.54-O1).
LD15610

SECTION 2 - SYSTEM OPERATING PROCEDURES
JOHNSON CONTROLS 13
FORM 160.75-O1 (211)
For display messages and information pertaining to the
operation refer to Optiview™ Control Center – Opera-
tion and Maintenance (Form 160.54-O1).
Any malfunctions which occur during
STOP/RESET are also displayed.
CHILLER OPERATION
The unit capacity will vary to maintain the leaving
CHILLED LIQUID TEMPERATURE setpoint by the
Pre-rotation Vanes which are modulated by an actua-
tor under the control of the Microprocessor Board. The
vane control routine employs proportional plus deriva-
tive (rate) control action. A drop in chilled liquid tem-
perature will cause the actuator to close the Prerotation
Vanes to decrease chiller capacity. When the chilled
liquid temperature rises, the actuator will open the Pre-
rotation Vanes to increase the capacity of the chiller.
However, the current draw (amperes) by the compres-
sor motor is also limited to FLA setpoint by the micro-
processor.
If the load continues to decrease, after the Prerotation
Vanes are entirely closed, the chiller will be shut down
by the Leaving Chilled Liquid – Low Temperature
Control.
CONDENSER WATER TEMPERATURE
CONTROL
The YORK chiller is designed to use less power by tak-
ing advantage of lower than design temperatures that
are naturally produced by cooling towers throughout
the operating year. Exact control of condenser water
such as a cooling tower bypass, is not necessary for
most installations. The minimum entering condenser
water temperature for full and part load conditions is
specified in the chiller engineering guide.
where:
Min. ECWT = LCWT – C RANGE + 5ºF + 12 ( )
Min. ECWT = LCWT – C RANGE + 2.8ºC + 6.6 ( )
ECWT = Entering Condensing Water Temperature
LCWT = Leaving Chilled Water Temperature
C Range = Condensing water temperature range at the
given load condition.
% Load
100
% Load
100
At start-up, the entering condenser water temperature
may be as much as 25°F (14°C) colder than the stand-
by return chilled water temperature. Cooling tower fan
cycling will normally provide adequate control of the
entering condenser water temperature on most instal-
lations.
Heat recovery chillers and chillers using optional head
pressure control would use a signal provided by the
microprocessor to control main condenser bundle heat
rejection or pressure, respectively.
OPERATING LOG SHEET
A permanent daily record of system operating condi-
tions (temperatures and pressures) recorded at regular
intervals throughout each 24 hour operating period
should be kept.
An optional status printer is available for this purpose
or Figure 8 on Page 14 shows a log sheet used by
Johnson Controls Personnel for recording test data on
chiller systems. It is available from the factory in pads
of 50 sheets each under Form 160.44-F7 and may be
obtained through the nearest Johnson Controls office.
Automatic data logging is possible by connecting the
optional printer and programming the DATA LOG-
GER function.
An accurate record of readings serves as a valuable ref-
erence for operating the system. Readings taken when
a system is newly installed will establish normal condi-
tions with which to compare later readings.
For example, an increase in condenser approach tem-
perature (condenser temperature minus leaving con-
denser water temperature) may be an indication of
dirty condenser tubes.
OPERATING INSPECTIONS
By following a regular inspection using the display
readings of the Microcomputer Control Center, and
maintenance procedure, the operator will avoid serious
operating difficulty. The following list of inspections
and procedures should be used as a guide.
Daily
1. Check OptiView™ Control Center displays.
2. If the compressor is in operation, check the bear-
ing oil pressure on the SYSTEM Screen. Also
check the oil level in the oil reservoir. Operating
oil level should be operating range of oil indicator.
Drain or add oil if necessary.
2

FORM 160.75-O1 (211)
JOHNSON CONTROLS
14
SECTION 2 - SYSTEM OPERATING PROCEDURES
3. Check entering and leaving condenser water pres-
sure and temperatures for comparison with job
design conditions. Condenser water temperatures
can be checked on the SYSTEM Screen.
4. Check the entering and leaving chilled liquid tem-
peratures and evaporator pressure for compari-
son with job design conditions on the SYSTEM
Screen.
5. Check the condenser saturation temperature
(based upon condenser pressure sensed by the
condenser transducer) on the SYSTEM Screen.
6. Check the compressor discharge temperature on
the SYSTEM Screen. During normal operation
discharge temperature should not exceed 220°F
(104°C).
7. Check the compressor motor current on the
SYSTEM Screen.
8. Check for any signs of dirty or fouled condenser
tubes. (The temperature difference between water
leaving condenser and saturated condensing tem-
perature should not exceed the difference recorded
for a new unit by more than 4°F (2.2°C)).
Weekly
1. Check the refrigerant charge. (Refer to Checking
The Refrigerant Charge During Unit Shutdown
on Page 30.)
Monthly
1. Leak check the entire chiller.
Quarterly
1. Perform chemical analysis of oil.
Semi-Annually (or more often as required)
1. Changeandinspectcompressoroillterelement.
2. Oil return system.
A. Change dehydrator.
B. Check nozzle of eductor for foreign par-
ticles.
3. Check controls and safety cutouts.
FIGURE 8 - LIQUID CHILLER LOG SHEETS
*NOTE: These items can be printed by an electronic printer connected to the Microboard
and pressing the PRINT key on the Keypad, or automatically using the Data Logger feature.
LD00467
23889A

SECTION 2 - SYSTEM OPERATING PROCEDURES
JOHNSON CONTROLS 15
FORM 160.75-O1 (211)
2
Annually (more often if necessary)
1. Drain and replace the oil in the compressor oil
sump. (Refer to Oil Charging Procedure on Page
24.)
2. Evaporator and Condenser.
A. Inspect and clean water strainers.
B. Inspect and clean tubes as required.
C. Inspect end sheets.
3. Compressor Drive Motor (See motor manufactur-
ers maintenance and service instruction supplied
with unit)
A. Clean air passages and windings per manu-
facturers instructions.
B. Meg motor windings – Refer to Figure 16 on
Page 30 for details.
C. Lubricate per motor manufacturer recom-
mendations.
4. Inspect and service electrical components as neces-
sary.
5. Perform refrigerant analysis.
If quarterly inspection indicates oil is ne,
replacing the oil is not necessary
NEED FOR MAINTENANCE OR SERVICE
If the system is malfunctioning in any manner or the
unit is stopped by one of the safety controls, consult
the Operation Analysis Chart, Table 1 on Page 25 of
this manual. After consulting this chart, if you are un-
able to make the proper repairs or adjustments to start
the compressor or the particular trouble continues to
hinder the performance of the unit, please call the near-
est Johnson Controls District Office. Failure to report
constant troubles could damage the unit and increase
the cost of repairs.
STOPPING THE SYSTEM
The Optiview™ Control Center can be programmed to
start and stop automatically (maximum, once each day)
whenever desired. Refer to the Optiview™ Control
Center – Operation and Maintenance (Form 160.54-
O1). To stop the chiller, proceed as follows:
1. Push the soft shutdown key on the homescreen on
the OptiView panel or rapid stop with the COM-
PRESSOR STOP/RESET switch. The compressor
will stop automatically. The oil pump will contin-
ue to run for coastdown period. The oil pump will
then stop automatically.
2. Stop the chilled water pump (if not wired into the
Microcomputer Control Center, in which case it
will shut off automatically simultaneously with the
oil pump.) (The actual water pump contact opera-
tion is dependent upon the position of Microboard
jumper J54.)
3. Open the switch to the cooling tower fan motors,
if used.
4. The compressor sump oil heater is energized when
the unit is stopped.
PROLONGED SHUTDOWN
If the chiller is to be shut down for an extended period
of time (for example, over the winter season), the fol-
lowing paragraphs outline the procedure to be followed.
1. Test all system joints for refrigerant leaks with a
leak detector. If any leaks are found, they should
be repaired before allowing the system to stand
for a long period of time.
During long idle periods, the tightness of the sys-
tem should be checked periodically.
2. If freezing temperatures are encountered while
the system is idle, carefully drain the cooling wa-
ter from the cooling tower, condenser, condenser
pump, and the chilled water system-chilled water
pump and coils.
Open the drains on the evaporator and condenser
liquid heads to assure complete drainage. (If a
Variable Speed Drive, drain its cooling system.
If Solid State Starter equipped drain liquid from
starter cooling loop.)
3. If freezing temperatures are encountered for peri-
ods longer than a few days, the refrigerant should
be recovered to containers to prevent leakage from
O-ring joints.
4. On the SETUP Screen, disable the clock. This
conserves the battery.
5. Open the main disconnect switches to the com-
pressor motor, condenser water pump and the
chilled water pump. Open the 115 volt circuit to
the Control Center.

FORM 160.75-O1 (211)
JOHNSON CONTROLS
16
SECTION 2 - SYSTEM OPERATING PROCEDURES
THIS PAGE INTENTIONALLY LEFT BLANK

JOHNSON CONTROLS 17
FORM 160.75-O1 (211)
SECTION 3 - SYSTEM COMPONENTS DESCRIPTION
GENERAL
The YORK Model YK Centrifugal Liquid Chiller is
completely factory-packaged including evaporator,
condenser, compressor, motor, lubrication system,
OptiView Control Center, and all interconnecting unit
piping and wiring.
COMPRESSOR
The compressor is a single-stage centrifugal type pow-
ered by an open-drive electric motor.
The rotor assembly consists of a heat-treated alloy steel
drive shaft and impeller shaft with a cast aluminum,
fully shrouded impeller. The impeller is designed for
balanced thrust and is dynamically balanced and over-
speed tested. The inserted type journal and thrust bear-
ings are fabricated of aluminum alloy. Single helical
gears with crowned teeth are designed so that more
than one tooth is in contact at all times. Gears are inte-
grally assembled in the compressor rotor support and
are film lubricated. Each gear is individually mounted
in its own journal and thrust bearings.
The open-drive compressor shaft seal is a double bel-
lows cartridge style with ceramic internal and atmo-
spheric seal faces. The seal is oil-flooded at all times
and is pressure-lubricated during operation.
CAPACITY CONTROL
Prerotation vanes (PRV) modulate chiller capacity
from 100% to as low as 15% of design for normal air
conditioning applications. Operation is by an external,
electric PRV actuator which automatically controls the
vane position to maintain a constant leaving chilled liq-
uid temperature.
COMPRESSOR LUBRICATION SYSTEM
The chiller lubrication system consists of the oil pump,
oil filter, oil cooler and all interconnecting oil piping
and passages. There are main points within the com-
pressor 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 re-
verse).
2. Compressor Driven Shaft (High Speed)
A. Forward and reverse high speed thrust
bearing.
B. Two journal bearings.
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 en-
ergized. After a 50 second pre-lube period, the com-
pressor 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
emergency oil reservoir where it is distributed to the
compressor bearings. The oil lubricates the compressor
rotating components and is returned to the oil sump.
There is an emergency oil reservoir located at the high-
est point in the lubrication system internally in the com-
pressor. It provides an oil supply to the various bear-
ings and gears in the event of a system shutdown due
to power failure. The reservoir, located on the top of
the compressor, allows the oil to be distributed through
the passages by gravity flow, thus providing necessary
lubrication during the compressor coastdown.
OIL PUMP
For normal operation, the oil pump should operate at
all times during chiller operation.
On shutdown of the system for any reason, the oil
pump operates and continues to run for 150 seconds.
The system cannot restart during that time interval.
3

FORM 160.75-O1 (211)
JOHNSON CONTROLS
18
SECTION 3 - SYSTEM COMPONENTS DESCRIPTION
FRONT VIEW
FIGURE 9 - SYSTEM COMPONENTS FRONT VIEW
VARIABLE
SPEED
DRIVE
EVAPORATOR
COMPRESSOR
SUCTION
RELIEF
VALVES
SIGHT
GLASS
VARIABLE SPEED
OIL PUMP
CONTROL BOX
OPTIVIEW CONTROL
CENTER
LD15222

SECTION 3 - SYSTEM COMPONENTS DESCRIPTION
JOHNSON CONTROLS 19
FORM 160.75-O1 (211)
3
LD15223
FIGURE 10 - SYSTEM COMPONENTS REAR VIEW
DISCHARGE
LINE
COMPRESSOR
OIL PUMP
HOUSING
LIQUID LINE
REAR VIEW
MOTOR
CONDENSER

FORM 160.75-O1 (211)
JOHNSON CONTROLS
20
SECTION 3 - SYSTEM COMPONENTS DESCRIPTION
HOT
THERMISTOR
OIL
HEATER
ANGLE
DRAIN VALVE
OIL
FILTER
OIL
SUMP OIL
PUMP
SUCTION
SUBMERSIBLE
OIL PUMP
WITH 3-PHASE MOTOR
LOW OIL
PRESSURE
TRANSDUCER
SIGHT
GLASSES
OIL
COOLER
OIL TEMP.
CONTROL
REFRIG.
THRUST
COLLAR
BEARING
(PRV)
INLET
VALVES
BEARING
(PINION GEAR
SHAFT)
IMPELLER
H.S.
SHAFT
SEAL
LOW SPEED
THRUST
COVER
LOW
SPEED GEAR
LOW SPEED-
GEAR REAR
BEARING
DOUBLE
BELLOWS
SHAFT SEAL
HIGH SPEED
THRUST COVER
THRUST COLLAR
MAIN JOURNAL
AND THRUST
BEARING
HIGH
PRESSURE
TRANSDUCER
EMERGENCY
OIL RESERVE
COMPRESSOR ROTOR
SUPPORT SECTION
OIL
FIGURE 11 - SCHEMATIC DRAWING – (YK) COMPRESSOR LUBRICATION SYSTEM
LD15200