York YK M3 M3 G4 operation manual Chiller Starting Sequence & Shutdown Sequence

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SYSTEM STARTING & SHUTDOWN SEQUENCE

OPERATOR INITIATED

(NOTE 2)

LD00952

NOTES: 1. REF. MICROBOARD PROGRAM JUMPER JP6

2. REF. MICROBOARD PROGRAM JUMPER JP4

FIG. 15 – CHILLER STARTING SEQUENCE & SHUTDOWN SEQUENCE

However, the current draw (amperes) by the compres- sor motor cannot exceed the setting of the % CUR- RENT LIMIT at any time during the unit operation, since the MicroComputer Control Center 40 to 100% three- phase peak current limit software function, plus the 3- phase 100% solid state overload current limiter (CM-

2)on Electro-Mechanical Starter applications or the Solid State Starter current Limit function will override the temperature control function and prevent the Pre- rotation Vanes from opening beyond the % CURRENT LIMIT setting.

If the load continues to decrease, after the Prerotation Vanes are entirely closed, the chiller will be shut down by the Low Water Temperature control (LWT) function which is displayed on the Control Center as:

MON 10:30 AM – LOW WATER TEMPERATURE – AUTOSTART

This occurs when the leaving water temperature falls to 4°F below setpoint or 36°F, whichever is higher. The LWT is part of the Micro Board.

NOTE: If the temperature setpoint has been repro- grammed within the last 10 minutes, the LWT cutout is 36°F for 10 minutes.

Condenser Water Temperature Control

The YORK Millennium chiller is designed to use less power by taking advantage of lower than design tem- peratures that are naturally produced by cooling tow- ers throughout the operating year. Exact control of con- denser water such as a cooling tower bypass, is not necessary for most installations. The chiller requires only that the minimum condenser water temperature

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YORK INTERNATIONAL

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Contents Centrifugal Liquid Chillers With Microcomputer Control CenterTable of Contents Nomenclature System Operation Description See Fig SectionDescription of System and Fundamentals of Operation Detail a Compressor Prerotation Vanes Capacity ControlSection Microcomputer Control Center Microcomputer Control Center and KeypadIntroduction Condenser Refrigerant LevelDisplaying System Parameters Control CenterOperation Psid = HOP LP Offset Pressure To Display Chilled Liquid TemperaturesTo Display OIL Pressure System Setpoints To Display Motor CurrentTo Display Operating Hours and Starts Counter See Programming System Setpoints, Displaying System Setpoints To Display Undervoltage setpoints Press Access Code key ProgrammingMicrocomputer Control Center Programming System SetpointsElectro-Mechanical Starter, refer to Fig Solid State Starter, refer to FigKeypad Programming Pull Down Demand Setpoint SetpointKeypad Programming Daily Schedule Setpoint Keypad Programming Holiday Service Keys PRE-ROTATION Vanes KeysOther Service Keys Pulldn Level = XXX% Setp = XXX% Actual = XXX%Operating Modes Compressor Switch Display MessagesSystem RUN Auto Vanes System Shutdown Messages When Control Center is in Remote mode MON Xxxx AM Evap Trans or Probe Error Therefore Function Jumper PositionThen MON Xxxx AM High Line Voltage MON Xxxx AM High Speed Drain Temp System Operating Procedures START-UP ProcedureOIL Heaters Checking the OIL Level in the OIL ReservoirSTART-UP Chiller OperationCondenser Water Temperature Control Chiller Starting Sequence & Shutdown SequenceEcwt LchwtChecking Operation Operating LOG SheetOperating Inspections See Section DailyWeekly QuarterlyNeed for Maintenance or Service Normal and Safety System ShutdownsSafety Shutdowns Cycling ShutdownsProlonged Shutdown START-UP After Prolonged ShutdownSystem Components Description System ComponentsGeneral CompressorCompressor Lubrication System See Fig Speed Increasing GearsSchematic Drawing YK Compressor Lubrication System OIL Heater Motor DrivelineHeat Exchangers Refrigerant Flow ControlVariable Speed Drive Optional Microcomputer Control Center See SectionSolid State Starter Optional Changing the Dehydrator Operational MaintenanceOIL Return System OIL Charging Procedure OIL ChargeTroubleshooting RiseLEP Operating Setpoints System After Service Operating Analysis Chart Symptom Abnormally LOW Suction PressureSymptom High Cooler Pressure Symptom no OIL Pressure When System Start Button PushedSymptom OIL Pump Vibrates or is Noisy Symptom OIL Pump Fails to Deliver OIL PressureSymptom Reduced OIL Pump Capacity OIL Pressure display keyConducting R-22 Pressure Test MaintenanceLeak Testing During Operation Vacuum Testing System PressuresVacuum Dehydration OperationRefrigerant Charge Refrigerant ChargingChecking the Refrigerant Charge During Unit Shutdown Handling Refrigerant for Dismantling and Repairs Megging the MotorMotor Stator Temperature and Insulation Resistances Condensers and Coolers Testing for Cooler and Condenser Tube Leaks Compressor Electrical ControlsPreventive Maintenance Pressure TestingCompressor Motor Cooler and CondenserElectrical Controls ALL Rights Reserved

YK M3 M3 G4 THRU YK S6 S4 J2, YK LB LB G4 THRU YK SE SC J4, YK M3 M3 G4 specifications

The York YK M3 M3 G4, YK M3 M3 G4 THRU YK S6 S4 J2, and YK LB LB G4 THRU YK SE SC J4 represent a sophisticated line of HVAC systems engineered for modern commercial applications. These models are celebrated for their innovative designs, energy efficiency, and advanced features, making them a preferred choice among facility managers and building owners.

One of the standout characteristics of the York YK series is its modular construction, which provides unparalleled flexibility in system configuration. This design allows for easy upgrades and expansions as building demands evolve. The YK M3 series, in particular, is equipped with advanced controls that enhance system performance while minimizing energy consumption. With features like variable speed drives and sophisticated control algorithms, these units optimize airflow and refrigerant use, significantly reducing operational costs.

Another notable aspect of the YK M3 M3 G4 is its robust refrigeration technology. Utilizing high-efficiency scroll compressors, these chillers deliver impressive cooling capacities while maintaining high energy efficiency ratings. Integrated with low GWP (Global Warming Potential) refrigerants, they meet modern environmental standards, ensuring compliance with regulations while promoting sustainability.

The YK LB LB G4 and YK SE SC J4 models further enhance York’s portfolio with their compact designs and lower installation footprints. These chillers are ideal for applications where space is at a premium. Additional features include advanced noise reduction technology, allowing for quieter operation compared to traditional HVAC systems, making them suitable for urban environments or buildings where noise control is a priority.

Furthermore, York's commitment to continuous innovation is evident in the incorporation of smart technology across its chiller series. Features such as connectivity options for monitoring and diagnostics through mobile apps or web interfaces empower users to maintain optimal system performance proactively. This connectivity aids in predictive maintenance, enabling timely interventions that extend equipment life and reliability.

Finally, all these high-efficiency chillers are backed by York's renowned service support network, ensuring that customers have access to expert assistance and maintenance services whenever needed. With their exceptional features, modern technologies, and commitment to sustainability, the York YK M3 M3 G4, YK M3 M3 G4 THRU YK S6 S4 J2, and YK LB LB G4 THRU YK SE SC J4 models stand out as leaders in the commercial HVAC market, setting new standards for performance and efficiency.