York YK M3 M3 G4 THRU YK S6 S4 J2, YK LB LB G4 THRU YK SE SC J4 Condensers and Coolers

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FORM 160.49-O2

CONDENSERS AND COOLERS

GENERAL

Maintenance of condenser and cooler shells is impor- tant 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 fol- lowing pages.

CHEMICAL WATER TREATMENT

Since the mineral content of the water circulated through coolers and condensers varies with almost every source of supply, it is possible that the water being used may corrode the tubes or deposit heat re- sistant scale in them. Reliable water treatment compa- nies are available in most larger cities to supply a wa- ter treating process which will greatly reduce the cor- rosive and scale forming properties of almost any type of water.

As a preventive measure against scale and corrosion and to prolong the life of cooler and condenser tubes, a chemical analysis of the water should be made prefer- ably before the system is installed. A reliable water treatment company can be consulted to determine whether water treatment is necessary, and if so, to furnish the proper treatment for the particular water condition.

CLEANING COOLER AND CONDENSER TUBES

COOLER

It is difficult to determine by any particular test whether possible lack of performance of the water cooler 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 ca- pacity decreases and the split (temperature difference between water leaving the cooler and the refrigerant temperature in the cooler) increases. A gradual drop- off in cooling capacity can also be caused by a gradual leak of refrigerant from the system or by a combina- tion of fouled tubes and shortage of refrigerant charge. An excessive quantity of oil in the cooler can also con- tribute to erratic performance.

CONDENSER

In a condenser, trouble due to fouled tubes is usually indicated by a steady rise in head pressure, over a period of time, accompanied by a steady rise in con- densing temperature, and noisy operation.These symp- toms may also be due to foul gas buildup. Purging will remove 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 usually 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 effectively by circulating an acid solution through the tubes.

TUBE CLEANING PROCEDURES

BRUSH CLEANING OF TUBES

If the tube consists of dirt and sludge, it can usually be removed by means of the brushing process. Drain the water sides of the circuit to be cleaned (cooling water or chilled water) remove the heads and thoroughly clean each tube with a soft bristle bronze brush. DO NOT USE A STEEL BRISTLE BRUSH. A steel brush may damage the tubes.

Improved results can be obtained by admitting water into the tube during the cleaning process. This can be done by mounting the brush on a suitable length of 1/8" pipe with a few small holes at the brush end and con- necting the other end by means of a hose to the water supply.

The tubes should always be brush cleaned before acid cleaning.

ACID CLEANING OF TUBES

If the tubes are fouled with a hard scale deposit, they must be acid cleaned. It is important that before acid cleaning, the tubes be cleaned by the brushing pro- cess described above. If the relatively loose foreign material is removed before the acid cleaning, the acid solution will have less material to dissolve and flush from the tubes with the result that a more satisfactory cleaning job will be accomplished with a probable sav- ing of time.

COMMERCIAL ACID CLEANING

In many major cities, commercial organizations now offer a specialized service of acid cleaning coolers and condensers. If acid cleaning is required, YORK

YORK INTERNATIONAL

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Contents With Microcomputer Control Center Centrifugal Liquid ChillersTable of Contents Nomenclature Description of System and Fundamentals of Operation SectionSystem Operation Description See Fig Capacity Control Detail a Compressor Prerotation VanesMicrocomputer Control Center and Keypad Section Microcomputer Control CenterCondenser Refrigerant Level IntroductionOperation 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 Programming System Setpoints Press Access Code keyProgramming Microcomputer Control CenterSolid State Starter, refer to Fig Electro-Mechanical Starter, refer to FigSetpoint Keypad Programming Pull Down Demand SetpointKeypad Programming Daily Schedule Setpoint Keypad Programming Holiday PRE-ROTATION Vanes Keys Service KeysPulldn Level = XXX% Setp = XXX% Actual = XXX% Other Service KeysOperating Modes Display Messages Compressor SwitchSystem 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 Reservoir System Operating ProceduresSTART-UP Procedure OIL Heaters Checking the OIL Level in the OILChiller Operation START-UPChiller Starting Sequence & Shutdown Sequence Condenser Water Temperature ControlOperating LOG Sheet EcwtLchwt Checking OperationQuarterly Operating Inspections See SectionDaily WeeklyCycling Shutdowns Need for Maintenance or ServiceNormal and Safety System Shutdowns Safety ShutdownsSTART-UP After Prolonged Shutdown Prolonged ShutdownSystem Components System Components DescriptionSpeed Increasing Gears GeneralCompressor Compressor Lubrication System See FigSchematic Drawing YK Compressor Lubrication System Refrigerant Flow Control OIL HeaterMotor Driveline Heat ExchangersSolid State Starter Optional Microcomputer Control Center See SectionVariable Speed Drive Optional OIL Return System Operational MaintenanceChanging the Dehydrator OIL Charge OIL Charging ProcedureRise TroubleshootingLEP Operating Setpoints System After Service Symptom no OIL Pressure When System Start Button Pushed Operating Analysis ChartSymptom Abnormally LOW Suction Pressure Symptom High Cooler PressureOIL Pressure display key Symptom OIL Pump Vibrates or is NoisySymptom OIL Pump Fails to Deliver OIL Pressure Symptom Reduced OIL Pump CapacityLeak Testing During Operation MaintenanceConducting R-22 Pressure Test System Pressures Vacuum TestingOperation Vacuum DehydrationChecking the Refrigerant Charge During Unit Shutdown Refrigerant ChargingRefrigerant Charge Megging the Motor Handling Refrigerant for Dismantling and RepairsMotor Stator Temperature and Insulation Resistances Condensers and Coolers Testing for Cooler and Condenser Tube Leaks Electrical Controls CompressorCooler and Condenser Preventive MaintenancePressure Testing Compressor MotorElectrical 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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