York YK M3 M3 G4 OIL Heater, Motor Driveline, Heat Exchangers, Refrigerant Flow Control

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oil pump sooner, depress the MANUAL OIL PUMP key again.

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.

OIL HEATER

During long idle periods, the oil in the compressor oil reservoir tends to absorb as much refrigerant as it can hold, depending upon the temperature of the oil and the pressure in the reservoir. As the oil temperature is lowered, the amount of refrigerant absorbed will be in- creased. If the quantity of refrigerant in the oil becomes excessive, violent oil foaming will result as the pres- sure within the system is lowered on starting.This foam- ing is caused by refrigerant boiling out of the oil as the pressure is lowered. If this foam reaches the oil pump suction, the bearing oil pressure will fluctuate with pos- sible temporary loss of lubrication, causing the oil pres- sure safety cutout to actuate and stop the system. See “Control Center, Section 2”.

To maintain the lowest possible concentration of re- frigerant in the oil, the compressor oil reservoir is equipped with a 115 volt electric reservoir oil heater. The oil heater is thermostatically controlled at all times during compressor shutdown to maintain the sump oil at 145°F to 155°F. If the oil temperature falls below 55°F, the display will read

SYSTEM SHUTDOWN – PRESS STATUS .

Pressing the STATUS key causes the message to read DAY 10:00 AM – LOW OIL TEMP – AUTO START . The system will be allowed to automatically restart when oil tem- perature rises to 30°F above condenser temperature.

MOTOR DRIVELINE

The compressor motor is an open-drip-proof, squirrel cage, induction type constructed to YORK design speci- fications. 60 hertz motors operate at 3570 rpm. 50 hertz motors operate at 2975 rpm.

(For 60 hertz motors 1750 HP and smaller; and 50 hertz motors 1400 HP and smaller) . . . the open motor is provided with a D-flange, factory mounted to a cast iron adapter mounted on the compressor.

(For 2000 HP 60 hertz motors; and 50 hertz motors above 1400 HP) . . . a separate structural steel base is furnished to provide rigid mounting of the compressor and motor, independent of the evaporator shell, to en- sure controlled alignment of the assembly. Motor is mounted with final alignment at start-up.

Motor drive shaft is directly connected to the com- pressor shaft with a flexible disc coupling. Coupling has all metal construction with no wearing parts to assure long life, and no lubrication requirements to pro- vide low maintenance.

For units utilizing remote electro-mechanical starters, a terminal box is provided for field connected conduit. Motor terminals are brought through the motor casing into the terminal box. Jumpers are furnished for three- lead type of starting. Motor terminal lugs are not fur- nished. Overload/overcurrent transformers are fur- nished with all units. For units furnished with factory packaged Solid State Starters, (optional) see right.

HEAT EXCHANGERS

Evaporator and condenser shells are fabricated from rolled carbon steel plates with fusion welded seams.

Heat exchanger tubes are internally enhanced type.

The evaporator is a shell and tube, flooded type heat exchanger. A distributor trough provides uniform distri- bution of refrigerant over the entire shell length. Alumi- num mesh eliminators are located above the tube bundle to prevent liquid refrigerant carryover into the com- pressor. Two 1-1/2" liquid level sight glasses are lo- cated on the side of the shell to aid in determining proper refrigerant charge. The evaporator shell con- tains a dual refrigerant relief valve.

The condenser is a shell and tube type, with a dis- charge gas baffle to prevent direct high velocity im- pingement on the tubes. A separate subcooler is lo- cated in the condenser.

The removable compact water boxes are fabricated of steel. The design working pressure is 150 psig and the boxes are tested at 225 psig. Integral steel water baffles provide the required pass arrangements. Stub-out wa- ter nozzle connections with Victaulic grooves are welded to the water boxes. These nozzle connections are suitable for Victaulic couplings, welding or flanges, and are capped for shipment. Plugged 3/4" drain and vent connections are provided in each water box.

REFRIGERANT FLOW CONTROL

Refrigerant flow to the evaporator is controlled by a single fixed-orifice (or variable orifice).

Chillers can be provided with a REFRIGERANT LEVEL CONTROL (EPROM version C.02.F(T).13 or later sup- ports this feature). A level sensor senses the refriger- ant level in the condenser and outputs an analog volt-

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YORK INTERNATIONAL

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Contents Centrifugal Liquid Chillers With Microcomputer Control CenterTable of Contents Nomenclature Description of System and Fundamentals of Operation SectionSystem Operation Description See Fig Detail a Compressor Prerotation Vanes Capacity ControlSection Microcomputer Control Center Microcomputer Control Center and KeypadIntroduction Condenser Refrigerant LevelOperation Control CenterDisplaying System Parameters To Display OIL Pressure To Display Chilled Liquid TemperaturesPsid = HOP LP Offset Pressure To Display Operating Hours and Starts Counter To Display Motor CurrentSystem Setpoints 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 Then Function Jumper PositionTherefore 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 ControlSolid State Starter Optional Microcomputer Control Center See SectionVariable Speed Drive Optional OIL Return System Operational MaintenanceChanging the Dehydrator 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 keyLeak Testing During Operation MaintenanceConducting R-22 Pressure Test Vacuum Testing System PressuresVacuum Dehydration OperationChecking the Refrigerant Charge During Unit Shutdown Refrigerant ChargingRefrigerant Charge 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.
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