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JOHNSON CONTROLS

FORM 160.67-O2

ISSUE DATE: 10/9/2020

SECTION 6 - MAINTENANCE

CHECKING THE REFRIGERANT CHARGE

DURING UNIT SHUTDOWN

The refrigerant charge is specified for each chiller

model on the unit data plate. Charge the correct amount

of refrigerant and record the level in the evaporator

sight glass.
The refrigerant charge should always be checked and

trimmed when the system is shut down.
The refrigerant charge level must be checked after the

pressure and temperature have equalized between the

condenser and evaporator. This would be expected

to be 4 hours or more after the compressor and water

pumps are stopped. The level should visible in the sight

glass.
Charge the refrigerant in accordance with the method

shown under the “Refrigerant Charging”, above. The

refrigerant level should be observed and the level re-

corded after initial charging.

HANDLING REFRIGERANT FOR

DISMANTLING AND REPAIRS

If it becomes necessary to open any part of the refriger-

ant system for repairs, it will be necessary to remove

the charge before opening any part of the unit. If the

chiller is equipped with optional valves, the refrigerant

can be isolated in either the condenser or evaporator /

compressor while making any necessary repairs.

REFRIGERANT CONDENSERS AND

EVAPORATORS
General

Maintenance of the refrigerant condenser, steam con-

denser, and evaporator shells is important to provide

trouble free operation of the chiller. The water side of

the tubes in the shell must be kept clean and free from

scale. Proper maintenance such as tube cleaning, and

testing for leaks, is covered on the following pages.

CHEMICAL WATER TREATMENT

Since the mineral content of the water circulated

through evaporators and condensers varies with almost

every source of supply, it is possible that the water be-

ing used may corrode the tubes or deposit heat resistant

scale in them. Reliable water treatment companies are

available in most larger cities to supply a water treat-

ing process which will greatly reduce the corrosive and

scale forming properties of almost any type of water.

As a preventive measure against scale and corrosion

and to prolong the life of evaporator and condenser

tubes, a chemical analysis of the water should be made

preferably before the system is installed. A reliable wa-

ter treatment company can be consulted to determine

whether water treatment is necessary, and if so, to fur-

nish the proper treatment for the particular water con-

dition.

CLEANING EVAPORATOR AND CONDENSER

TUBES
Evaporator

It is difficult to determine by any particular test wheth-

er possible lack of performance of the water evaporator

is due to fouled tubes alone or due to a combination

of troubles. Trouble which may be due to fouled tubes

is indicated when, over a period of time, the cooling

capacity decreases and the split (temperature differ-

ence between water leaving the evaporator and the

refrigerant temperature in the evaporator) increases. A

gradual drop-off in cooling capacity can also be caused

by a gradual leak of refrigerant from the system or by a

combination of fouled tubes and shortage of refrigerant

charge. An excessive quantity of oil in the evaporator

can also contribute to erratic performance.

Condenser

In a condenser, trouble due to fouled tubes is usually

indicated by a steady rise in head pressure, over a pe-

riod of time, accompanied by a steady rise in condens-

ing temperature, and noisy operation. These symptoms

may also be due to foul gas buildup. Purging will re-

move the foul gas revealing the effect of fouling.

TUBE FOULING

Fouling of the tubes can be due to deposits of two types

as follows:

1. Rust or sludge

– which finds its way into the

tubes and accumulates there. This material usu-

ally does not build up on the inner tube surfaces

as scale, but does interfere with the heat transfer.

Rust or sludge can generally be removed from the

tubes by a thorough brushing process.

2. Scale

– due to mineral deposits. These deposits,

even though very thin and scarcely detectable

upon physical inspection, are highly resistant to

heat transfer. They can be removed most effec

tively by circulating an acid solution through the

tubes.

Summary of Contents for YST

Page 1: ...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 ...

Page 2: ...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...

Page 3: ...ice 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 oth...

Page 4: ...erent starting configurations 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 S...

Page 5: ...eck 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 ...

Page 6: ...igerant 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 T...

Page 7: ...mp 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 ...

Page 8: ...ndenser 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 8...

Page 9: ...stem 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 Bea...

Page 10: ...JOHNSON CONTROLS 10 FORM 160 67 O2 ISSUE DATE 10 9 2020 THIS PAGE INTENTIONALLY LEFT BLANK ...

Page 11: ...of project specific details GENERAL SYSTEM DESCRIPTION The YORK Model YST Chiller is a factory assembled steam turbine driven centrifugal compressor chiller It is commonly applied to large air conditioning sys tems 700 through 2165 Tons but may be used on other chiller applications The YST chiller operates on Refrigerant R 134a and is designed only for NEMA 1 indoor installation or a weather prote...

Page 12: ...tor is pumped to the point of use which may be air conditioning terminal units and or central sta tion air handling units and or other equipment requir ing cooling The warmed liquid is then returned to the chiller to complete the chilled liquid circuit The con denser water is supplied from a cooling tower system or sometimes other sources of water suitable for con densing service The chiller is co...

Page 13: ...pplications If the tower water temperatures must be held above 75ºF for other chillers on the same tower circuit the capacity control logic can be programmed to automati cally limit the amount of speed reduction and PRV clo sure to maintain stable operation The hot gas bypass valve is then modulated to admit condenser gas into the evaporator and reduce the cooling effect as required This will main...

Page 14: ...GERANT FLOW THRU REFRIGERANT FLOW DIAGRAM LEGEND HIGH PRESSURE VAPOR HIGH PRESSURE LIQUID REFIGERANT LOW PRESSURE LIQUID REFIGERANT LOW PRESSURE VAPOR EVAPORATOR REFRIGERANT DRAIN AND CHARGING CONNECTION ELIMINATOR SUB COOLER CONDENSER DISCHARGE COMPRESSOR SUCTION HOT GAS BYPASS VALVE LEVEL CONTROL VALVE LIQUID LEVEL SENSOR LD09466 ...

Page 15: ...uired mechanical energy for a given load The turbine exhaust steam enters the steam con denser through the steam inlet connection on the top of the condenser and is distributed longitudinally over the tubes When the steam contacts the relatively cool tubes it condenses This condensing effect is a rapid change in state from a gas to a liquid which results in a great reduction in specific volume It ...

Page 16: ...OHNSON CONTROLS 16 FORM 160 67 O2 ISSUE DATE 10 9 2020 SECTION 1 DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION Figure 4 STEAM AND CONDENSATE FLOW STEAM AND CONDENSATE FLOW DIAGRAM GOVERNOR LD12547 ...

Page 17: ...DAMENTALS OF OPERATION FORM 160 67 O2 ISSUE DATE 10 9 2020 1 Figure 5 STEAM CONDENSER HOTWELL LEVEL SWITCHES LD09905 Level Transmitter High Level Switch Magnetic Level Indicator Oper Level 7 5 7 5 5 5 5 5 Low Level Switch STEAM CONDENSER HOTWELL LEVEL SWITCHES ...

Page 18: ...JOHNSON CONTROLS 18 FORM 160 67 O2 ISSUE DATE 10 9 2020 SECTION 1 DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION THIS PAGE INTENTIONALLY LEFT BLANK ...

Page 19: ...ition of the chiller components oil heat er on oil pump running etc If displays are not cor rect perform diagnostic checks per Form 160 67 M3 and correct the problem prior to operating the chiller Removal of foreign material from the inlet steam piping is the responsibility of the party installing the piping Be sure to blow out and clean all steam lines before connecting to the turbine Failure to ...

Page 20: ...the steam condenser vacuum pump sealing water should be inspected and cleaned periodically and checked for possible damage INSPECT AND CLEAN THE TURBINE Before a turbine is operated certain parts must be cleaned to remove the effects of transit and storage Protective mylar sheets installed between the journal bearing and the shaft journal must be removed prior to rotating the shaft See FLUSH THE T...

Page 21: ... up per half of the bearing and remove all pieces of my lar protection above and below from the shaft This must be done at both the steam and exhaust end bear ings Housings must be cleaned and resealed with Tite Seal to prevent oil leaks at the case split line Ring Oil Lubrication The oil level gauge on the side of the bearing housing indicates the oil level A mark inscribed on the lower half bear...

Page 22: ...nd replace the fuses FU10 FU11 and FU12 Close the main three phase disconnect switch and use the MANUAL key to verify that the oil pump operates properly VERIFY THE TURBINE GOVERNOR VALVE OPERATION Ensure that the main steam inlet block valve steam inlet slow roll bypass valve bypass valve turbine pneumatic trip valve and turbine governor valve are fully closed While viewing the ANALOG I O EXPANSI...

Page 23: ...point Ensure that the Hotwell Pump Motor Protector Over load Switches are both in the OFF position BUMP test the condensate pump and standby pump if supplied motors for proper rotation The easiest way to do this is to first put the selected pump in the Man ual mode using the Pump Mode key on the CONDEN SATE SCREEN and immediately place the selected hotwell pump motor protector overload switch in t...

Page 24: ...ad switches are in the OFF position BUMP test the vacuum pump and standby pump if supplied motors for proper rotation The easiest way to do this is to first put the selected pump in the manual mode While viewing the VACUUM SCREEN on the OptiView Control Center use the vacuum pump Pump Mode key to put the selected pump in the Manu al mode In the Manual Mode if the pump motor does not start within 5...

Page 25: ...he proper level in the valve PREPARE THE CHILLED AND CONDENSER WATER PIPING AND PUMPS Ensure that the pump motor starters and any automatic isolation valves located in the inlet outlet piping are operable Before the initial operation of the pumps both water circuits should be thoroughly vented of all air at the high points Failure to do so will result in pass baffle damage PREPARE THE PRESSURE POW...

Page 26: ...lve enough to obtain a trickle flow out the overflow line This will ensure that atmospheric relief valve sealing water is present to the proper level in the valve 7 Ensure that sealing water is available for the vac uum pump s 8 If the OptiView Control Center is used to initi ate the chilled and condenser liquid flow to the chiller ensure that any manual isolation valves in the chilled and condens...

Page 27: ...ontrol panel on systems furnished with Manual Startup and is accomplished automati cally on systems furnished with Auto matic Startup If the steam turbine has remained warm for some time after a shutdown because of a leaking throttle valve or if it displays ab normal vibration during slow roll startup or at design speed it is possible the shaft has taken a bow because of heat distor tion The shaft...

Page 28: ...aphs variable speed control is described To simplify the start up procedure and provide enhanced speed control during slow roll and low load operation chillers manufactured after December 2006 are supplied with enhanced governor con trols The original turbine governor valve and actuator were replaced with a ball valve which is field installed in the main steam inlet line upstream of the turbine tr...

Page 29: ...MP ON ENERGIZE TURBINE STEAM RING DRAIN SOLENOID ENERGIZE OIL RETURN LIQUID LINE SOLENOIDS ENERGIZE TURBINE TRIP VACUUM BREAKER SOLENOIDS TURBINE AUX OIL PUMP ON AUTO ZEROING DIFFERENTIAL OIL PRESSURE TRANSDUCERS CHILLED LIQUID FLOW SWITCH BYPASS RUN TIME SEE NOTE 4 START UP TIME SLOW ROLL WARM UP SOFT SHUTDOWN TIME SEE NOTE 5 SYSTEM COASTDOWN OIL PRESSURE CHECK COMPRESSOR OIL PUMP ON HOTWELL PUMP...

Page 30: ...LIARY OIL PUMP ON ENERGIZE TURBINE STEAM RING DRAIN SOLENOID ENERGIZE OIL RETURN LIQUID LINE SOLENOIDS ENERGIZE TURBINE TRIP VACUUM BREAKER MAIN STEAM INLET BLOCK VALVE AIR DUMP SOLENOIDS TURBINE AUX OIL PUMP ON AUTO ZEROING DIFFERENTIAL OIL PRESSURE TRANSDUCERS CHILLED LIQUID FLOW SWITCH BYPASS RUN TIME SEE NOTE 4 START UP TIME SLOW ROLL WARM UP SOFT SHUTDOWN TIME SEE NOTE 5 SYSTEM COASTDOWN OIL ...

Page 31: ...t is initiated the main start relay K18 on the I O board is energized The turbine trip and vacuum breaker solenoid valves are energized the pneumatic turbine trip valve is opened the hotwell pump is started and the message SYSTEM STARTING is displayed at this time Automatic Start The main steam inlet block valve and slow roll bypass valve air dump solenoids are energized to apply supply air pressu...

Page 32: ...heck valve and solenoid valve in the turbine steam ring drain line the solenoid valve remains energized open dur ing the initial startup The check valve in the steam ring drain line prevents air from being drawn into the turbine when the turbine steam ring drops be low atmospheric pressure during the initial evacu ation and while the turbine is slow rolling When the inlet steam valves open to begi...

Page 33: ...ICIENT VACUUM is displayed if the turbine exhaust pressure is not less than the PSP6 Ready To Run Turbine Exhaust Pressure setpoint 12 PSIA and the vacuum pump is restarted This energizes the sealing water solenoid valve If flow is not established within 10 seconds after the pump start is initiated an alarm is sounded If the chiller is equipped with a standby vacuum pump it will be started to cont...

Page 34: ...iary oil pump will be stopped The oil return and liquid line solenoid valves are opened If the chiller is supplied with a solenoid valve in the turbine steam ring drain line it is de energized at this time Whenever the turbine bearing supply oil pressure falls below the auxiliary oil pump control setting the auxiliary pump motor will be restarted d At 3200 RPM the under speed safety log ic is enab...

Page 35: ...nt for 10 minutes the turbine will be tripped SYSTEM OPERATING PROCEDURE General Refer to the OPERATING INSPECTIONS in this manual for complete details on the routine operation of the equipment For turbines with pressure feed lubrica tion the oil pressure should be observed frequently until the turbine has been operated for several days as failure of oil pressure can result in extensive damage The...

Page 36: ...En abled or the Soft Shutdown logic has been un loading the chiller longer than the TDSP9 Soft Shutdown Rampdown Timeout minutes entered on the Time Setpoints Screen if HGV is Dis abled Automatic Start When the Soft Shutdown is initi ated the Main Steam Inlet Valve control output is first decreased ramped down at 5 second until it is equal to or less than the current output to the Governor Valve F...

Page 37: ...ed liquid pump unless the cycling shutdown message LEAVING CHILLED LIQ UID LOW TEMPERATURE is displayed in which case the contacts will remain closed If the Chilled Liquid Pump Operation is set for Enhanced on the Setup Screen the contacts will also remain closed if the cycling shutdown message SYSTEM CYCLING CONTACTS OPEN is displayed If the chilled liquid pump contacts are not used the plant con...

Page 38: ...f the high condenser pressure low evaporator pressure and torque limiting override PID controllers override the output of the primary Leav ing Chilled Liquid Temperature Controller to maintain stable operation and prevent the chiller from shutting down The tuning of the primary Leaving Chilled Liq uid Temperature Evaporator Pressure and Condenser Pressure PID controllers is automatically adjusted ...

Page 39: ...ed by modulating the hot gas bypass valve HGV Temperature Controller In some cases it may be desirable to allow the vanes to go completely closed which would leave no signal for the Hot Gas Ratio calculation to control the hot gas valve Aseparate PID controller is provided which con trols at a leaving chilled liquid temperature set point that is slightly below the main Leaving Chilled Liquid Tempe...

Page 40: ...apts to fluctuations in the quality of the steam sup plied to the turbine inlet If the calculated horsepower increases above the set point the output of the Turbine Horsepower Limit Controller will decrease LSR2 and LSR1 will select the lower signal to override the Leaving Chilled Liquid Temperature Controller output and unload the chiller as described above With the load reduced the turbine will ...

Page 41: ...or PRV control are loaded into the Leaving Chilled Liquid Temperature Controller and its output is set to the current PRV control signal which will be equal to the higher of the minimum start up value PRVM or the Minimum Vane Position Cal culation output The PRV will begin ramping open As the system pressure differential increases the output of the Minimum Speed Calculation will increase and the s...

Page 42: ...he load continues to decrease the Leaving Chilled Liquid Temperature Controller output will begin de creasing from 100 This signal is subtracted from 100 to provide the increasing signal required to open the HGV As the HGV is opened the system pressure differential will decrease resulting in lower outputs from the Minimum Speed Calculation and Minimum Vane Position Calculation The Capacity Ratchet...

Page 43: ... bearings are rated for or 115 of the turbine design horsepower whichever is lower The logic will calculate the actual horsepower based on the steam inlet temperature and pressure so that the override controller automatically adapts to fluctuations in the quality of the steam supplied to the turbine inlet If the calculated horsepower increases above the set point the output of the Turbine Horsepow...

Page 44: ...C 8 Complete a visual inspection of the Turbine for external damage or leaks 9 Inspect the Turbine for unusual vibration or noise 10 The turbine oil temperatures should be checked several times a day On KG turbine design oil temperature in the bearing oil should be between 130 and 180 F 54 C 82 C Cooling water flow should be adjusted to maintain this range On KD turbines the oil supply from the oi...

Page 45: ...running If there is any reason to suspect water in the oil open the reservoir drain slightly If water is present it will be the first thing to come out of the drain Refer to SECTION 4 OPERATIONAL MAINTENANCE to determine the possible cause and proce dure to follow 13 Observe if steam is venting from gland leak off line If the amount of steam is excessive and con denssate is draining from the exhau...

Page 46: ... as required c Inspect end sheets 3 Inspect and service electrical components as neces sary 4 Perform refrigerant analysis 5 Remove and clean the Steam Strainer on the Tur bine refer to the product specific Service manual for instructions 6 Inspect turbine shaft seals 7 Check thrust bearing end play 8 Remove and check the operation of the turbine Sentinel Warning Valve refer to the product spe cif...

Page 47: ...ed into the turbine casing to help keep the turbine dry If this type of corrosion in hibitor is used the main steam inlet and exhaust connection must be sealed off with blank flanges wood or metal to prevent the loss of the vapor inhibitor SYSTEM SHUTDOWN The following are methods for stopping the YST sys tem Normal Controlled Stop The chiller is un loaded prior to the actual de energizing of the ...

Page 48: ...a tion system prior to storage Cooling water to oil coolers should be positively shut off or disconnected Drain water from cooler if freezing temperatures are expected Other Recommendations If the turbine is to be idle for a period longer than eight months Johnson Controls Service office should be consulted as to the proper storage procedures Any other questions or concerns regarding off season st...

Page 49: ... VACUUM BREAKER SOLENOID VALVE TURBINE OIL COOLING WATER INLET VALVE COMPRESSOR OIL COOLING WATER INLET VALVE POWER PANEL CONDENSATE OVER BOARD VALVE CONDENSATE RECIRCULATION VALVE HOTWELL CONDENSATE PUMP 2 OPTIONAL HOTWELL CONDENSATE PUMP 1 HOTWELL CONDENSATE LEVEL INDICATOR TRANSMITTER VACUUM PUMP 1 VACUUM PUMP 2 VACUUM PUMP 2 SEALING WATER SOLENOID VALVE VACUUM PUMP 2 SEALING WATER FLOW SWITCH ...

Page 50: ...y through the compressor A stall pressure transducer mounted in the discharge scroll of the compressor detects the pressure pulsa tions created by the stall noise in the compressor dis charge and outputs DC voltage pulsations to the stall detector board in the OptiView Control Center This board converts the voltage pulsations into an analog voltage that represents the magnitude of the stall noise ...

Page 51: ... BEARING DOUBLE BELLOWS SHAFT SEAL LOW SPEED GEAR REAR BEARING LOW SPEED GEAR OIL RETURN LINE FROM EDUCTOR BLOCK SUMP PRESSURE TRANSDUCER low pressure OIL TEMPERATURE THERMISTOR LIQUID LEVEL GAUGE ANGLE DRAIN VALVE SUBMERSIBLE OIL PUMP WITH 3 PHASE MOTOR LIQUID COOLED OIL COOLER OIL TEMPERATURE CONTROL VALVE COOLING LIQUID 3 PHASE OIL HEATER OIL FILTER VENT LINE THRUST COLLAR BEARING PRV INLET VAN...

Page 52: ... the oil pump suction the bearing oil pressure will fluctuate with possible temporary loss of lubrication causing the oil pressure safety cutout to actuate and stop the system The oil heater is automatically controlled by the control panel at all times during shutdown slow roll and ramp up to rated speed to maintain the oil temperature in the oil reservoir at a target value which is 50 F above the...

Page 53: ... the control panel The other valve is the fast acting butterfly trip valve which is operated by the chiller control center the me chanical overspeed device or the manual trip device that can by actuated by the operator Refer to the fol lowing TURBINE GOVERNOR AND OVERSPEED CONTROLS section in this manual for additional de tails TURBINE BEARINGS The turbine bearings perform two functions The jour n...

Page 54: ... PUMP MOTOR KG TURBINE SMALL KD TURBINE LARGE LD09427a VACUUM BREAKER SOLENOID VACUUM BREAKER SOLENOID TURBINE TRIP VALVE LIMIT SWITCH TURBINE TRIP SOLENOID VALVE TURBINE NOZZLE VALVE AIR DUMP SOLENOID VALVE HAND TRIP KNOB GLAND LEAK OFF CONNECTION LEVEL GAUGE CONSTANT LEVEL OILER BREATHER FILTER ASSEMBLY SENTINEL WARNING VALVE SENTINEL WARNING VALVE OIL COOLER OUTLET THERMOMETER OIL COOLER INLET ...

Page 55: ...team turbines have a shaft mounted main oil pump The external lubrication system includes an remote lube oil reservoir with level gauge an open motor driven auxiliary oil pump not submersible as on the compressor oil pump water cooled shell and tube oil cooler with copper tubes 25 micron full flow oil fil ter dual oil filters available as a price addition Oil temperature control is by a three way ...

Page 56: ...rbines are equipped with a gland seal system similar to that of non condensing machines although the func tion is different The purpose of the sealing system is to keep outside air from leaking into the casing since it would reduce the vacuum and cause a loss of power The system is not as effective when the machine is standing idle as when it is operating The exhaust pressure in the casing is alwa...

Page 57: ...ndenser to help slow the turbine more quickly by increasing the exhaust pres sure on the turbine The entrance of air into the sys tem necessitates the operation of the vacuum pump to evacuate the air before the next startup may occur Steam Nozzle Valves Steam nozzle valves are furnished to provide added efficiency as load conditions change on the turbine The nozzle valves regulate the amount of st...

Page 58: ...d 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 An automatic pressure powered pump is supplied by Johnson Controls when the Auto Start option is ordered Liquid enters the pump body through the inlet check valve causing the float to rise As the chamber fills the valve changeover l...

Page 59: ...supply air pressure is relieved There is an overspeed trip that can be used by the operator in an emergency This manual trip is activated by an emergency trip knob at the base of the turbine that is connected to the same linkage as the mechanical overspeed trip See Figure 13 on page 60 HEAT EXCHANGERS Evaporator and refrigerant condenser shells are fabri cated from rolled carbon steel plates with ...

Page 60: ...quire readjustment of the anti surge setpoints to ensure proper operation of the Hot Gas Bypass Valve OPTIVIEW CONTROL CENTER The OptiView Control Center is factory mounted wired and tested The electronic panel automatically controls the operation of the unit in meeting system cooling requirements while minimizing energy usage For detailed information on how the Control Center controls the start u...

Page 61: ...re inte grated with the chiller control panel In addition auxil iary pressure gauges are located at the condenser steam inlet and hotwell pump discharge piping Temperature gauges are located at the steam inlet cooling water in let and outlet and the hotwell Piping is fitted with unions at suitable break points Steam Condenser A steam condenser is provided to condense the steam exhausted from the s...

Page 62: ...axis The impeller transmits the driving power to the water liquid ring which forms concentrically to the casing when the pump is started As the liquid moves outwards non condensible gas air is drawn into the pump compressed and expelled through the discharge port into a discharge separator that separates the water from the air Water is drained and not recirculated to the pump Approximately 3 5 GPM...

Page 63: ...drator use the following procedure 1 Shut the stop valves on the condenser gas line oil return line to the oil sump and inlet end of the de hydrator 2 Remove the dehydrator 3 Assemble the new filter drier 4 Open condenser stop valve and check dehydrator connections for refrigerant leaks 5 Open all the dehydrator stop valves to allow the liquid refrigerant to flow through the dehydrator and condens...

Page 64: ...mp discharge connection to the oil charg ing valve A located on the remote oil reservoir cover plate Do not tighten the connection at the charging valve until after the air is forced out by pumping a few strokes of the oil pump This fills the lines with oil and prevents air from being pumped into the system 3 Open the oil charging valve and pump oil into the system until oil level in the compresso...

Page 65: ...to the OFF position to pre vent the chiller from being accidentally started 1 Close the hand isolation valves on the inlet and outlet oil lines going to and from the oil filter 2 Relieve the refrigerant pressure and oil in the oil filter and the oil lines through the pressure access port fitting located on the top of the filter housing Connect a refrigeration pressure hose to the pres sure access ...

Page 66: ...t drains in the bearing housing should be checked weekly for water The presence of oil in the constant level oilers does not necessarily mean that oil in the bearing housings is at the proper level CLEANLINESS is ESSENTIAL for long and trouble free service from the BEARINGS Caremustbetakentoensure that no foreign material enters bearing housings or constant level oilers when performing maintenance...

Page 67: ...nd investigate any change gradual or sudden The most frequently encountered difficulty is pressure drop and the most common causes are clogged oil filter worn pump faulty relief valves in sufficient oil in the reservoir clogged piping entrained air and temperature elevation The most common sources of oil contamination are im purities picked up during storage shipping or adding of the lubricant dir...

Page 68: ... turbine bearings and replace them in the bearing housing Housings must be cleaned and resealed with Tite Seal to prevent oil leaks at the case split line 5 Check the condition and cleanliness of the oil fil ters furnished on the set and replace them with new filters if needed before continuing with the start up DETERMINING CORRECT REFRIGERANT CHARGE LEVEL The refrigerant charge level is correct w...

Page 69: ...t are found us ing the electronic leak detector Check refrigerant relief valve piping and tube rolled joints as part of the comprehensive refrigerant leak checking program Repair leaks before adding refrigerant PRESSURE CONNECTIONS All threaded pressure connections used on the YORK YST Chillers are SAE straight thread O ring face seal type fittings or Primore Rotalock fittings The O ring straight ...

Page 70: ...JOHNSON CONTROLS 70 FORM 160 67 O2 ISSUE DATE 10 9 2020 SECTION 4 OPERATIONAL MAINTENANCE THIS PAGE INTENTIONALLY LEFT BLANK ...

Page 71: ...em Subcooler level valve problem Remove obstruction Temperature difference between leaving chilled liquid and refrigerant in the evaporator greater than normal discharge temperature Evaporator tubes dirty or restricted Clean evaporator tubes Temperature of chilled liquid too low at minimum rated speed Insufficient load for system capacity Check prerotation vane and Hot gas valve operation and sett...

Page 72: ... hz to maintain target oil pressure Turbine supply pressure gradually drops as noted by log sheets Oil filter is dirty Change oil filter 9 Symptom Compressor Oil Pressure System Ceases to Return Oil Refrigerant Sample Oil refrigerant return not functioning Filter drier in oil return system dirty Replace old filter drier with new Jet or orifice of oil return jet clogged Remove jet inspect for dirt ...

Page 73: ...n EVACUATION AND DEHYDRATION OF UNIT Figure 18 EVACUATION OF CHILLER LD09698 CONNECT TO GAUGE CONNECTION ON THE CONDENSER OR EVAPORATOR VACUUM PUMP COMPRESSOR OIL COOLER THERMISTOR VACUUM GAUGE NOTES PSIG Lbs per sq in gauge pressure Pressure above atmosphere PSIA Lbs per sq in absolute pressure Sum of gauge plus atmospheric pressure Table 4 SYSTEM PRESSURES Gauge Absolute Boiling Temperatures of ...

Page 74: ...um Dehydration 2 Open wide all system valves Be sure all valves to the atmosphere are closed 3 Operate the vacuum pump in accordance with VACUUM DEHYDRATION until a wet bulb temperature of 32 F or a pressure of 5 mm Hg is reached See Table 4 for corresponding values of pressure 4 To improve evacuation circulate hot water not to exceed 125 F 51 7ºC through the evaporator and condenser tubes to thor...

Page 75: ... been evacuated from the system but there is still a small amount of moisture left In order to provide a me dium for carrying this residual moisture to the vacuum pump nitrogen should be introduced into the system to bring it to atmospheric pressure and the indicator tem perature will return to approximately ambient tempera ture Close off the system again and start the second evacuation The relati...

Page 76: ... which will greatly reduce the corrosive and scale forming properties of almost any type of water As a preventive measure against scale and corrosion and to prolong the life of evaporator and condenser tubes a chemical analysis of the water should be made preferably before the system is installed A reliable wa ter treatment company can be consulted to determine whether water treatment is necessary...

Page 77: ...ING FOR EVAPORATOR AND CONDENSER Tube Leaks Evaporator and condenser tube leaks in R 134a sys tems may result in refrigerant leaking into the water circuit or water leaking into the shell depending on the pressure levels If refrigerant is leaking into the water it can be detected at the liquid head vents after a period of shutdown If water is leaking into the refrigerant system capacity and effici...

Page 78: ...ue to accumulate and the same conditions continue to stop the unit operation after a new filter is installed notify the nearest Johnson Controls office to request the presence of a Johnson Controls Service Technician STEAM CONDENSER CONDENSATE PUMP MAINTENANCE While the pump is running re grease the pump bear ing with 2 lithium base petroleum grease This should be done after every 2500 hours of op...

Page 79: ... must be exercised to free them Tapping and rocking as described above should be continued pos sibly tapping directly on the circumference of the dia phragm or retainer plate by inserting a flat bar between the casing flanges against the diaphragm or plate and tapping on the exposed end After the parts are free a chain hoist can be used to remove cover and rotor The lower diaphragm portion cannot ...

Page 80: ...ambient tem peratures and operating conditions The following torques are to be applied to socket head and hex head capscrews bolts and nuts of SAE grade 8 alloy steel and 17 4 Ph stainless steel Table 5 TURBINE TIGHTENING TORQUES WITHOUT WASHERS SIZE FINAL TORQUE 1 4 130 in lbs 5 16 275 in lbs 3 8 490 in lbs 7 16 70 ft lbs 1 2 100 ft lbs 9 16 145 ft lbs 5 8 200 ft lbs 3 4 350 ft lbs 7 8 570 ft lbs...

Page 81: ...ater in cooling towers closed water systems etc frequently results in one or more of the following 1 Scale Formation 2 Corrosion or Rusting 3 Slime and Algae Formation It is therefore to the benefit of the user to provide for proper water treatment to provide for a longer and more economical life of the equipment The following recommendation should be followed in determining the condition of the w...

Page 82: ...ubes X Perform Oil Analysis On Compressor Lube Oil 1 X Perform Refrigeration Analysis 1 X Perform Vibration Analysis X Clean Heat Exchanger Tubes X 2 Perform Eddy Current Testing And Inspect Tubes 2 5 Years Check Operation of all Shutdowns History Print X Conduct Panel Overspeed Test X Check Operation of Motor Contactors in Power Panel X STEAM CONDENSER Visually Inspect For Leaks Abnormal Noise X ...

Page 83: ... Valve X Drain Clean Oil Reservoir X Drain Clean Governor If Applicable X Change Filter with Oil Change X Check Recalibrate Gauges X Open Inspect Turbine Replace as Required 3 Years Rotor 3 Years Labyrinth Seals 3 Years Bearings 3 Years Gland Seals 3 Years For operating and maintenance requirements listed above refer to appropriate service literature or contact your local Johnson Controls Service ...

Page 84: ...perature Difference Liquid Supply Temperature Supply Pressure Return Temperature Return Pressure Flow Rate GPM If equipped Condenser Refrigerant Condenser Pressure Corresponding Temperature Subcooler Liquid Temperature Small Temperature Difference Refrigerant Level Refrigerant Level Setpoint Liquid Supply Temperature Supply Pressure Return Temperature Return Pressure Flow Rate GPM If equipped 160 ...

Page 85: ...1 514 Issue Date June 20 2014 DATE TIME Hour Meter Reading O A Temperature Dry Bulb Wet Bulb Turbine Oil Level Oil Pressure KD Only Oil Temperature Bearing Temp DE NDE Inlet Steam Pressure Inlet Steam Temperature First Stage Pressure Exhaust Pressure Vibration Level DE NDE Gov Trip Valve Supply Air Press Steam Condenser Hotwell Level Hotwell Level Setpoint Leaving Water Temperature Remarks ...

Page 86: ...face finish because of the high velocities and sharp turning that are required by the design While corrosion and stress corrosion problems are unusual in steam plants such problems can result from boiler carry over due to inadequate de aeration and boiler feed water treat ment The chloride ion that is present in most industrial wa ter can cause stress corrosion problems but most typi cally it is a...

Page 87: ... FOR BOILER WATER BASED ON DRUM WATER ANALYSES PRESSURE AT OUTLET OF STEAM GENERATING UNIT PSIG TOTAL SOLIDS PPM OH ALKALINITY PPM SILICA PPM PHOSPHATE PPM SULFITE PPM HARDNESS PPM CHLORIDES PPM 0 150 151 450 451 750 751 900 2 000 1 500 1 000 750 200 100 60 55 50 35 25 10 50 50 25 25 30 30 25 20 0 0 0 0 250 200 150 50 ...

Page 88: ...m Fahrenheit to Celsius multiply by 5 9 or 0 5556 Example 10 0 F range x 0 5556 5 6 C range Table 8 SI METRIC CONVERSION MEASUREMENT MULTIPLY ENGLISH UNIT BY FACTOR TO OBTAIN METRIC UNIT Capacity Tons Refrigerant Effect ton 3 516 Kilowatts kW Power Horsepower 0 7457 Kilowatts kW Flow Rate Gallons Minute gpm 0 0631 Liters Second l s Length Feet ft 0 3048 Meters m Inches in 25 4 Millimeters mm Weigh...

Page 89: ...JOHNSON CONTROLS 89 Notes FORM 160 67 O2 ISSUE DATE 10 9 2020 NOTES ...

Page 90: ... Pennsylvania USA 17349 1 800 524 1330 Subject to change without notice Printed in USA Copyright by Johnson Controls 2020 www johnsoncontrols com ALL RIGHTS RESERVED Form 160 67 O2 1020 Issue Date October 9 2020 Supersedes 160 67 O2 415 ...

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