York Yst Troubleshooting guide

MODEL YST

CENTRIFUGAL LIQUID CHILLER

DESIGN LEVEL F AND G

STEAM TURBINE

CENTRIFUGAL LIQUID CHILLERS

OPERATION & MAINTENANCE Supersedes: 160.67-O2 (415) Form 160.67-O2 (1020)

Issue Date:

October 9, 2020

JOHNSON CONTROLS

FORM 160.67-O2

ISSUE DATE: 10/9/2020

This equipment is a relatively complicated apparatus.

During rigging, installation, operation, maintenance,

or service, individuals may be exposed to certain com-

ponents or conditions including, but not limited to:

heavy objects, 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 responsibility of rigging, instal-

lation, and 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

rigging, installation, and operating/service personnel. It

is expected that these individuals possess independent

training that will enable them to perform their assigned

tasks properly and safely. It is essential that, prior to

performing any task on this equipment, this individual

shall have read and understood the on-product labels,

this document and any referenced materials. This in-

dividual shall also be familiar with and comply with

all applicable industry and governmental standards and

regulations 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 control 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 accor-

dance 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 warn-

ing will void the manufacturer’s warranty and cause serious damage to property or personal injury.

JOHNSON CONTROLS 3

FORM 160.67-O2

ISSUE DATE: 10/9/2020

MANUAL DESCRIPTION FORM NUMBER

Unit Installation Manual 160.67-N2

OptiViewTM Control Center - Operation Manual 160.67-O1

Wiring Diagram - Model YST (Style F) 160.67-PW6

Renewal Parts - Unit 160.67-RP1

Renewal Parts - Controls and Instrumentation 160.67-RP2

ASSOCIATED LITERATURE

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.

Johnson Controls makes no commitment to update

or provide current information automatically to the

manual or product owner. Updated manuals, if appli-

cable, can be obtained by contacting the nearest John-

son Controls Service office or accessing the Johnson

Controls Knowledge Exchange website at https://docs-

johnsoncontrols-uat.fluidtopics.net/chillers/home.

It is the responsibility of rigging, lifting, and operating/

service personnel to verify the applicability of these

documents to the equipment. If there is any question

regarding the applicability of these documents, rig-

ging, lifting, and operating/service personnel should

verify whether the equipment has been modified and

if current literature is available from the owner of the

equipment prior to performing any work on the chiller.

AFFECTED PAGES DESCRIPTION

3 Conditioned Based Maintenance information added

REVISION NOTES

Revisions made to this document are indicated in the following table. These revisions are to technical information,

and any other changes in spelling, grammar, or formatting are not included.

CONDITIONED BASED MAINTENANCE

Traditional chiller maintenance is based upon assumed

and generalized conditions. In lieu of the traditional

maintenance program, a Johnson Controls YORK

Conditioned Based Maintenance (CBM) program can

be substituted. This CBM service plan is built around

the specific needs for the chiller, operating conditions,

and annualized impact realized by the chiller. Your lo-

cal Johnson Controls Branch can propose a customized

Planned Service Agreement that leverages real time

and historical data, delivering performance reporting,

corrective actions required and data enabled guidance

for optimal operation and lifecycle assurance. The pro-

gram will include fault detection diagnostics, operation

code statistics, performance based algorithms and ad-

vance rules based rationale delivered by the Johnson

Controls Connected Equipment Portal.

JOHNSON CONTROLS

FORM 160.67-O2

ISSUE DATE: 10/9/2020

1. Steam Turbine- Smaller capacity YST chillers are

tted with a Murray Turbine design, K2G or KG,

which will be referred to in this manual as KG.

The larger units include a larger Murray Turbine

design, KD. The speed control for the two turbine

designs are similar but mechanically the two mod-

els are dierent not only in size and capacity but

also notably the lubrication system design which

is covered further in this document.

2. System Starting- The YST Chiller is available

in two dierent starting congurations, namely

manual and automatic. Both are covered in this

document.

NOMENCLATURE

The model number denotes the following characteristics of the unit.

YST VF VD J4 - KD71750090 - 14 - 0.6 - 33192C - F S

Chiller Model Special (Mandatory)

Evaporator Code Design Level

Condenser Code Steam Condenser Model

Compressor Code Turbine Expansion Ratio

No. of Turbine Nozzles

Steam Turbine Base Model

SYSTEM DESIGN VARIATIONS

3. Hot Well Pump and Vacuum Pump for Steam Sys-

tem- Single pumps for both is the standard selec-

tion. An option for dual pumps, (for standby) on

both hot well and vacuum service is available.

Be sure to note which variation is fur-

nished with your system and be guided by

the sections that follow in this instruction

booklet.

JOHNSON CONTROLS 5

FORM 160.67-O2

ISSUE DATE: 10/9/2020

TABLE OF CONTENTS

SECTION 1 - DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION.................................. 11

General System Description........................................................................................................................... 11

Refrigeration System Operation .....................................................................................................................12

Capacity Controls ...........................................................................................................................................12

Steam and Condensate Flow .........................................................................................................................15

SECTION 2 - PRE-STARTUP AND SYSTEM OPERATING PROCEDURES ..................................................19

Overview ........................................................................................................................................................19

Pre-Startup Procedures – Initial And After Long Term Shutdown ..................................................................19

Check The Status Of The Main Steam Supply ..............................................................................................19

Blow-Down The Inlet Steam Line ...................................................................................................................19

Inspect And Clean Steam Strainers ...............................................................................................................20

Inspect And Clean Water Strainers ................................................................................................................20

Inspect And Clean The Turbine ......................................................................................................................20

Flush The Turbine Lube System (Pressure Lubrication Turbine Only)...........................................................20

Check The Oil Level In The Turbine Bearing Reservoirs (Ring Oil Lubrication) ............................................ 21

Check The Coupling And Alignment...............................................................................................................21

Check The Refrigerant Charge.......................................................................................................................21

Oil Heaters .....................................................................................................................................................21

Oil Heater Operation ......................................................................................................................................21

Check The Oil Level In The Compressor Oil Reservoir..................................................................................22

Check The Status Of All Utilities..................................................................................................................... 22

Verify The Compressor Oil Pump Operation .................................................................................................. 22

Verify The Turbine Governor Valve Operation................................................................................................22

Verify The Compressor Pre-Rotation Vane Operation....................................................................................23

Verify The Hot Gas Bypass And Subcooler Level Control Valve Operation ..................................................23

Prepare The Steam Condenser Hotwell And Pumps ..................................................................................... 23

Prepare The Steam Condenser Vacuum Pumps ........................................................................................... 24

Prepare The Steam Condenser Atmospheric Relief Valve.............................................................................25

Prepare The Chilled And Condenser Water Piping And Pumps..................................................................... 25

Prepare The Pressure Powered Pump...........................................................................................................25

Verify All User Defined Setpoints....................................................................................................................25

Pre-Startup Procedures – After Short Term Shutdown...................................................................................25

Sequence Of Operation..................................................................................................................................26

Slow Roll Time Calculation.............................................................................................................................27

Overview ........................................................................................................................................................28

Startup Sequence Of Operation ....................................................................................................................31

System Operating Procedure .........................................................................................................................35

General..................................................................................................................................................35

Hourly ....................................................................................................................................................35

Shut Down Sequence Of Operation ...............................................................................................................36

Normal (Controlled) Stop.......................................................................................................................36

Immediate Stop .....................................................................................................................................36

Post Trip Shutdown Sequence ..............................................................................................................36

Capacity Controls ..........................................................................................................................................38

Overview ...............................................................................................................................................38

Fixed Speed Chiller Capacity Controls Operation..........................................................................................38

Fixed Speed Chiller Loading Sequence .........................................................................................................38

JOHNSON CONTROLS

FORM 160.67-O2

ISSUE DATE: 10/9/2020

Fixed Speed Chiller Unloading Sequence...................................................................................................... 39

PRV Control ..........................................................................................................................................39

Hot Gas Ratio Control ...........................................................................................................................39

HGV Temperature Controller.................................................................................................................39

Fixed Speed Chiller Override Controllers.......................................................................................................39

High and Low Refrigerant Pressure ......................................................................................................39

Turbine Governor Position Power Limiting............................................................................................39

Turbine Horsepower Limiting.................................................................................................................40

Variable Speed Chiller Capacity Controls Operation......................................................................................40

Variable Speed Chiller Loading Sequence....................................................................................................41

Hot Gas Mode .......................................................................................................................................41

PRV Mode .............................................................................................................................................41

Speed Mode ..........................................................................................................................................41

Variable Speed Chiller Unloading Sequence .................................................................................................41

Speed Mode ..........................................................................................................................................41

PRV Mode .............................................................................................................................................42

Hot Gas Mode .......................................................................................................................................42

Variable Speed Chiller Override Controllers...................................................................................................42

High and Low Refrigerant Pressure ......................................................................................................42

Turbine Governor Position Power Limiting............................................................................................42

Turbine Horsepower Limiting.................................................................................................................43

Operating Log Sheet ......................................................................................................................................43

Operating Inspections ....................................................................................................................................44

Daily ......................................................................................................................................................44

Ring Oil Lubrication ...............................................................................................................................45

Pressure Lubrication .............................................................................................................................45

Weekly...................................................................................................................................................45

Monthly..................................................................................................................................................45

Quarterly................................................................................................................................................45

Semi-Annually (or more often as required) ...........................................................................................46

Annually (more often if necessary)........................................................................................................46

3 Year ....................................................................................................................................................46

Need For Maintenance Or Service.................................................................................................................46

System Shutdown ..........................................................................................................................................47

Prolonged Shutdown ......................................................................................................................................47

Turbine O󰀨-Season Storage..................................................................................................................47

Turbine Steam Path .............................................................................................................................47

Turbine Lubrication System...................................................................................................................48

Other Recommendations ......................................................................................................................48

Steam Condenser O󰀨-Season Storage ................................................................................................48

SECTION 3 - SYSTEM COMPONENTS DESCRIPTION...................................................................................49

General...........................................................................................................................................................50

Compressor Variable Geometry Diffuser (VGD).............................................................................................50

Compressor Lubrication System ....................................................................................................................50

Compressor Oil Pump ....................................................................................................................................52

Compressor OIL HEATER..............................................................................................................................52

Steam Turbine ............................................................................................................................................... 52

Steam Turbine Inlet Valves.............................................................................................................................53

Turbine Bearings ............................................................................................................................................53

TABLE OF CONTENTS (CONT'D)

JOHNSON CONTROLS 7

FORM 160.67-O2

ISSUE DATE: 10/9/2020

Turbine Lubrication Systems ..........................................................................................................................53

KG Steam Turbine with Ring Oil Lubrication .........................................................................................55

KD Steam Turbine with External Pressurized Lube System .................................................................55

KD Turbine Auxiliary Oil Pump ..............................................................................................................55

Turbine Gland Seal System...................................................................................................................55

Types of Gland Leak-O󰀨 Systems.........................................................................................................55

Gland Seal System: Standard YST Condensing Turbines .................................................................... 56

Gland Seal Wear ...................................................................................................................................56

Gland Seal Leak-O󰀨 Piping ..................................................................................................................56

Gland Leak-O󰀨 Condenser - Optional Supply by Special Quotation..................................................... 57

Vacuum Breaker Solenoid Valve ...........................................................................................................57

Steam Nozzle Valves ............................................................................................................................57

Sentinel Warning Valve .........................................................................................................................57

Steam Ring Drain ..................................................................................................................................57

Pressure Powered Condensate Drain Pump ........................................................................................58

A Factory supplied automatic pressure powered pump is provided for draining condensate from the

steam turbine casing, during operation. The pressure power pump is shipped loose and all piping and

installation is provided by others. ..........................................................................................................58

Condensate Drain Tank – Optional Supply by Special Quotation ......................................................... 58

Turbine Governor And Overspeed Controls ...................................................................................................59

Heat Exchangers............................................................................................................................................59

Refrigerant Flow Control ................................................................................................................................60

Optional Service Isolation Valves ...................................................................................................................60

Hot Gas Bypass .............................................................................................................................................60

Optiview™ Control Center.............................................................................................................................. 60

Power Panel ...................................................................................................................................................61

Steam Condenser Package ...........................................................................................................................61

Steam Condenser ...............................................................................................................................61

Atmospheric Relief Valve ......................................................................................................................61

Hotwell (Condensate) Pump .................................................................................................................62

Vacuum Pump .......................................................................................................................................62

Level Control .........................................................................................................................................62

SECTION 4 - OPERATIONAL MAINTENANCE .................................................................................................63

Compressor Oil Return System...................................................................................................................... 63

Changing The Dehydrator ..............................................................................................................................63

The Compressor Oil Charge ..........................................................................................................................64

Compressor Oil Charging Procedure .............................................................................................................64

Compressor Oil Filter .....................................................................................................................................65

Single Oil Filter Replacement................................................................................................................65

Dual Oil Filter Replacement .................................................................................................................66

Turbine Oil Maintenance ................................................................................................................................66

Ring Oil Lubrication ...............................................................................................................................66

Pressure Lubrication .............................................................................................................................67

Lube Oil Flushing ..................................................................................................................................68

Determining Correct Refrigerant Charge Level ..............................................................................................68

Refrigerant Charging .............................................................................................................................69

Refrigerant Leak Checking.............................................................................................................................69

Pressure Connections ....................................................................................................................................69

TABLE OF CONTENTS (CONT'D)

JOHNSON CONTROLS

FORM 160.67-O2

ISSUE DATE: 10/9/2020

SECTION 5 – TROUBLESHOOTING ..................................................................................................................71

SECTION 6 - MAINTENANCE .............................................................................................................................73

Renewal Parts ................................................................................................................................................73

Checking System For Leaks ..........................................................................................................................73

Leak Testing During Operation..............................................................................................................73

Evacuation And Dehydration Of Unit..............................................................................................................73

Conducting R-22 Pressure Test......................................................................................................................74

Vacuum Testing ..............................................................................................................................................74

Vacuum Dehydration ......................................................................................................................................74

Operation........................................................................................................................................................75

Refrigerant Charging ......................................................................................................................................75

Checking The Refrigerant Charge During Unit Shutdown..............................................................................76

Handling Refrigerant For Dismantling And Repairs........................................................................................76

Refrigerant Condensers And Evaporators...................................................................................................... 76

General..................................................................................................................................................76

Chemical Water Treatment.............................................................................................................................76

Cleaning Evaporator And Condenser Tubes ..................................................................................................76

Evaporator.............................................................................................................................................76

Condenser.............................................................................................................................................76

Tube Fouling...................................................................................................................................................76

Tube Cleaning Procedures.............................................................................................................................77

Brush Cleaning of Tubes .......................................................................................................................77

Acid Cleaning Of Tubes.........................................................................................................................77

Commercial Acid Cleaning .............................................................................................................................77

Testing For Evaporator And Condenser ........................................................................................................77

Tube Leaks............................................................................................................................................77

Compressor Maintenance ..............................................................................................................................78

Steam Condenser Condensate Pump Maintenance ......................................................................................78

Steam Condenser Vacuum Pump Maintenance.............................................................................................78

Turbine Internal Inspection .............................................................................................................................78

Check The Casing Interior For Foreign Material Before Closing....................................................................80

Electrical Controls ..........................................................................................................................................80

SECTION 7 - PREVENTIVE MAINTENANCE ....................................................................................................81

Compressor....................................................................................................................................................81

Leak Testing ...................................................................................................................................................81

Evaporator And Refrigerant Condenser ......................................................................................................... 81

Oil Return System ..........................................................................................................................................81

Electrical Controls ..........................................................................................................................................81

Steam Purity/Turbine Deposits.......................................................................................................................86

Overview ...............................................................................................................................................86

Steam Purity...................................................................................................................................................86

Effects Of Deposits And Harmful Ions On Turbine ......................................................................................... 86

Detection Of Deposits ....................................................................................................................................86

Detection Of Corrosion...................................................................................................................................86

Temperature ...................................................................................................................................................88

NOTES....................................................................................................................................................................89

TABLE OF CONTENTS (CONT'D)

JOHNSON CONTROLS 9

FORM 160.67-O2

ISSUE DATE: 10/9/2020

LIST OF FIGURES

FIGURE 1 - Model YST Chiller .............................................................................................................................. 11

FIGURE 2 - Compressor Prerotation Vanes...........................................................................................................12

FIGURE 3 - Refrigerant Flow - Thru .......................................................................................................................14

FIGURE 4 - Steam And Condensate Flow ............................................................................................................16

FIGURE 5 - Steam Condenser Hotwell Level Switches .........................................................................................17

FIGURE 6 - Slow Roll Time calculation ..................................................................................................................27

FIGURE 7 - Operation Sequence Timing Diagram (Manual Start) ........................................................................29

FIGURE 8 - Operation Sequence Timing Diagram (Automatic Start).....................................................................30

FIGURE 9 - Liquid Chiller Log Sheets ....................................................................................................................44

FIGURE 10 - System Components.........................................................................................................................49

FIGURE 11 - Schematic Drawing – (YST) Compressor Lubrication System..........................................................51

FIGURE 12 - KD & KG Turbine Drawing ................................................................................................................54

FIGURE 13 - Overspeed Protection Knob Assembly .............................................................................................60

FIGURE 14 - Oil Return System.............................................................................................................................63

FIGURE 15 - Charging Oil Reservoir With Oil........................................................................................................64

FIGURE 16 - Standard Single Oil Filter And Optional Dual Oil Filter......................................................................65

FIGURE 17 - Dual Oil Filter Isolation Valve ............................................................................................................66

FIGURE 18 - Evacuation Of Chiller ........................................................................................................................73

FIGURE 19 - Saturation Curve...............................................................................................................................75

LIST OF TABLES

TABLE 1 - Recommended Maximum Turbine Bearing, Oil Sump, And Metal Temperatures.................................66

TABLE 2 - Refrigerant Charge Level......................................................................................................................68

TABLE 3 - Operation Analysis Chart ......................................................................................................................71

TABLE 4 - System Pressures.................................................................................................................................73

TABLE 5 - Turbine Tightening Torques (Without Washers) ....................................................................................80

TABLE 6 - Turbine Tightening Torques (With Washers) .........................................................................................80

TABLE 7 - Recommended Limits For Boiler Water (Based On Drum Water Analyses). ........................................87

TABLE 8 - SI Metric Conversion.............................................................................................................................88