Carrier 19XL specifications Troubleshooting Guide

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TROUBLESHOOTING GUIDE

Overview Ð The PIC has many features to aid the operator and the technician in troubleshooting a 19XL chiller.

·By using the LID display, the chiller actual operating con- ditions can be viewed while the unit is running.

·When an alarm occurs, the default LID screen will freeze at the time of alarm. The freeze enables the operator to view the chiller conditions at the time of alarm. The Status tables will still show the current information. Once all alarms have been cleared, the default LID screens will return to normal operation.

·The Control Algorithm Status tables will display various screens of information in order to diagnose problems with chilled water temperature control, chilled water temper- ature control overrides, hot gas bypass, surge algorithm status, and time schedule operation.

·The Control Test feature allows proper operation and test- ing of temperature sensors, pressure transducers, the guide vane actuator, oil pump, water pumps, tower control, and other on/off outputs while the compressor is stopped. It also has the ability to lock off the compressor and turn on water pumps for pumpout operation. The display will show the required temperatures and pressures during these operations.

·Other Service menu tables can access con®gured items, such as chilled water resets, override set points, etc.

·If an operating fault is detected, an alarm message is gen- erated and displayed on the LID default screen. A more detailed message Ð along with a diagnostic message Ð also is stored into the Alarm History table.

Checking the Display Messages Ð The ®rst area to check when troubleshooting the 19XL is the LID display. If the alarm light is ¯ashing, check the primary and second- ary message lines on the LID default screen (Fig. 13). These messages will indicate where the fault is occurring. The Alarm History table on the LID Service menu will also carry an alarm message to further expand on this alarm. For a com- plete listing of messages, see Table 9. If the alarm light starts to ¯ash while accessing a menu screen, depress

EXIT to return to the Default screen to read the failure

message. The compressor will not run with an alarm con- dition existing, unless the alarm type is an unauthorized start or a failure to shut down.

Checking Temperature Sensors Ð All tempera- ture sensors are of the thermistor type. This means that the resistance of the sensor varies with temperature. All sensors have the same resistance characteristics. Determine sensor temperature by measuring voltage drop if the controls are powered, or resistance if the controls are powered off. Com- pare the readings to the values listed in Tables 10A or 10B.

RESISTANCE CHECK Ð Turn off the control power and disconnect the terminal plug of the sensor in question from the module. Measure sensor resistance between recep- tacles designated by the wiring diagram with a digital ohm- meter. The resistance and corresponding temperature is listed in Tables 10A or 10B. Check the resistance of both wires to ground. This resistance should be in®nite.

VOLTAGE DROP Ð Using a digital voltmeter, the voltage drop across any energized sensor can be measured while the control is energized. Tables 10A or 10B lists the relation- ship between temperature and sensor voltage drop (volts dc measured across the energized sensor). Exercise care when measuring voltage to prevent damage to the sensor leads, connector plugs, and modules. Sensors should also be checked

at the sensor plugs. Check the sensor wire at the sensor for 5 vdc if the control is powered.

Relieve all refrigerant pressure or drain the water prior to replacing the temperature sensors.

CHECK SENSOR ACCURACY Ð Place the sensor in a medium of a known temperature and compare that temper- ature to the measured reading. The thermometer used to determine the temperature of the medium should be of lab- oratory quality with 0.5° F (.25° C) graduations. The sensor in question should be accurate to within 2° F (1.2° C).

See Fig. 8 for sensor locations. The sensors are immersed directly in the refrigerant or water circuits. The wiring at each sensor is easily disconnected by unlatching the connector. These connectors allow only one-way connection to the sensor. When installing a new sensor, apply a pipe sealant or thread sealant to the sensor threads.

DUAL TEMPERATURE SENSORS Ð There are 2 sensors each on the bearing and motor temperature sensors for servicing convenience. In case one of the dual sensors is damaged, the other one can be used by moving a wire.

The number 2 terminal in the sensor terminal box is the common line. To use the second sensor, move the wire from the number 1 position to the number 3 position.

Checking Pressure Transducers Ð There are 3 pressure transducers on the 19XL. These determine cooler, condenser, and oil pressure. The cooler and condenser trans- ducers also are used by the PIC to determine the refrigerant temperatures. All 3 can be calibrated if necessary. It is not usually necessary to calibrate at initial start-up. However, at high altitude locations, calibration of the transducer will be necessary to ensure the proper refrigerant temperature/ pressure relationship. Each transducer is supplied with 5 vdc power from a power supply. If the power supply fails, a transducer voltage reference alarm will occur. If the trans- ducer reading is suspected of being faulty, check the supply voltage. It should be 5 vdc ± .5 v. If the supply voltage is correct, the transducer should be recalibrated or replaced.

IMPORTANT: Whenever the oil pressure or the cooler pressure transducer is calibrated, the other sensor should be calibrated to prevent problems with oil differential pressure readings.

Calibration can be checked by comparing the pressure readings from the transducer against an accurate refrig- eration gage. These readings are all viewed or calibrated from the Status01 table on the LID. The transducer can be checked and calibrated at 2 pressure points. These calibration points are 0 psig (0 kPa) and between 240 and 260 psig (1655 to

1793 kPa). To calibrate these transducers:

1.Shut down the compressor.

2.Disconnect the transducer in question from its Schrader ®tting.

NOTE: If the cooler or condenser vessels are at 0 psig (0 kPa) or are open to atmospheric pressure, the trans- ducers can be calibrated for zero without removing the transducer from the vessel.

3.Access the Status01 table, and view the particular trans- ducer reading; it should read 0 psi (0 kPa). If the reading is not 0 psi (0 kPa), but within ± 5 psi (35 kPa), the value

may be zeroed by pressing the SELECT softkey while the highlight bar is located on the transducer, and then by pressing the ENTER . The value will now go to zero.

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Contents Start-Up, Operation, and Maintenance Instructions Safety ConsiderationsContents Contents Introduction Abbreviations and ExplanationsChiller Familiarization Refrigeration CycleMOTOR/OIL Refrigeration Cooling Cycle 19XL Rear View Condenser In/Out Temperature Sensors Take-Apart Rabbet Fit ConnectorCooler In/Out Temperature Sensors Cooler Pressure Schrader FittingLubrication Cycle Refrigerant Motor Cooling and Oil Cooling CyclesLubrication System Starting Equipment Unit-Mounted Solid-State Starter OptionalMajor PIC Components Panel Locations DenitionsControls PIC Component Panel19XL Controls and Sensor Locations Pressure Transducer, TypicalPower Panel with Options Control and OIL Heater Voltage Selector S1LID Operation and Menus Fig GeneralSelect − Example of Point Status Screen Status01 Override OperationsExample of Time Schedule Operation Screen 19XL Menu Structure 19XL Service Menu Structure 19XL Service Menu Structure Setpoint Example of Set Point ScreenExample 1 Ð STATUS01 Display Screen Description Range Units Reference Point Name Alarm HistoryLID Screens Menu Status SelectExample 4 Ð Setpoint Display Screen Example 2 Ð STATUS02 Display ScreenExample 3 Ð STATUS03 Display Screen MenuECW Control Option Example 5 Ð Configuration Config Display ScreenExample 6 Ð LEAD/LAG Configuration Display Screen ICE Build TerminationExample 7 Ð SERVICE1 Display Screen Example 9 Ð SERVICE3 Display Screen Example 8 Ð SERVICE2 Display ScreenSpare Alert Enable Menu ServiceDischarge Temperature Example 10 Ð Maintenance MAINT01 Display ScreenExample 11 Ð Maintenance MAINT02 Display Screen Bearing TemperatureExample 12 Ð Maintenance MAINT03 Display Screen Example 13 Ð Maintenance MAINT04 Display ScreenDescription RANGE/STATUS Units Reference Point Name PIC System Functions Page Protective Safety Limits and Control Settings Capacity Overrides Page Page Hgbp Lead/Lag ControlECW Hot Gas BypassPage Ice Build Control Cent CapacityPage Example of Attach to Network Device Screen To LOG onSTART-UP/SHUTDOWN/RECYCLE Sequence FigRecycle Restart Delta T Job Data Required Using the Optional Storage Tank and PumpoutBefore Initial START-UP Equipment Required19XL Leak Test Procedures Page Ð HCFC-22 Pressure Ð Temperature F Ð HCFC-22 Pressure Ð Temperature CÐ HFC-134a Pressure Ð Temperature F Ð HFC-134a Pressure Ð Temperature CTemperature Pressure Page Inspect Wiring Check Optional Pumpout Compressor Water PipCheck Starter MECHANICAL-TYPE StartersBenshaw, Inc. Solid-State Starter Power Stack BENSHAW, INC. SOLID-STATE StarterPower Up the Controls and Check the Oil Heater Set Up Chiller Control CongurationLoad Surge Prevention Occurs TOO Soon Occurs TOO Late Amps Correction Factors For 19XL Motors Volt Motor CodeControl Test Menu Functions Charge Refrigerant into Chiller19XL Chiller Equalization Without PUMP- OUT Unit Tests to be Devices Tested PerformedCooler Refrigerant Charges19XL Total Refrigerant Charge SizeInitial START-UP Dry Run to Test Start-Up SequenceCheck Rotation Operating Instructions Check Oil Pressure and Compressor StopCalibrate Motor Current Operator DutiesTo Stop the Chiller Plant Transfer Refrigerant from Storage Tank to Chiller Pumpout and Refrigerant Transfer ProceduresOperating the Optional Pumpout Compressor TstatChillers with Isolation Valves Transfer the Refrigerant from Chiller to Storage TankGeneral Maintenance Test After Service, Repair, or Major Leak Ð IfReturn Refrigerant to Normal Operating Conditions Weekly Maintenance Guide Vane Actuator LinkageScheduled Maintenance Check Safety and Operating Controls MonthlyTo Change the OIL Compressor Bearing and Gear Mainten Inspect the Heat Exchanger TubesOptional Pumpout System Controls Troubleshooting Guide MAINT03 MAINT01MAINT02 MAINT04Shutdown with ON/OFF/RESET-OFF Timing OUT or Timed OUTRecycle Shutdown Normal or AUTO.-RESTARTAutorestart in Progress LOW Chilled Water Normal RUN with RESET, TEMPERATURE, or Demand Compressor Jumpstart and Refrigerant ProtectionNormal RUN Overrides Active Alerts OUT-OF-RANGE Sensor FailuresLimited Chiller Protect Limit Faults Protective LimitChiller Alerts Spare Sensor Alert MessagesOther PROBLEMS/MALFUNCTIONS DESCRIPTION/MALFUNCTION Probable CAUSE/REMEDYÐ Thermistor Temperature F vs Resistance/Voltage Drop Temperature Voltage Resistance DropÐ Thermistor Temperature C vs Resistance/Voltage Drop Control Modules Module AddressInput Options Module Starter Management Module SMM Fig Processor Module Psio FigOptions Module Installation Switch Options Setting ModuleTypical Benshaw, Inc. Solid-State Starter internal View Page Page RV1 Benshaw, Inc. Solid-State Starter Troubleshooting GuideProblem Probable Causes Area of Correction SCRCooler Heat Exchanger DataAdditional Data for Marine Waterboxes CondenserCondensers Waterbox Cover WeightsCoolers 1034 kPaCompressor/Motor Weights Compressor WeightsOptional Pumpout System Electrical Data Compressor Fits and Clearances Ft-lb Compressor Assembly TorquesDescription Torque ``ZComm CLRCOM EXTPage CLR Page Chiller Power Panel, Starter Assembly Motor Wiring Schematic Chiller Power Panel, Starter Assembly Motor Wiring Schematic GFR PMRPOT HPSTypical Wye-Delta Unit Mounted Starter Wiring Schematic Index Index Copyright 1996 Carrier Corporation

19XL specifications

The Carrier 19XL is a highly regarded commercial heating and cooling solution, designed to provide optimum performance and energy efficiency in various applications. This rooftop unit is engineered to meet the diverse needs of businesses, making it an ideal choice for those requiring reliable climate control in their facilities.

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The Carrier 19XL features a user-friendly control system, allowing for easy monitoring and management of the unit's performance. This control system is designed to maximize energy savings, offering features such as demand control ventilation and integrated economizers that facilitate the use of outdoor air for cooling, reducing reliance on mechanical systems when conditions allow.

Construction-wise, the Carrier 19XL is built to withstand tough environmental conditions. Its robust cabinet is made from galvanized steel, providing durability and protection against the elements. The design also includes insulation to minimize noise levels, creating a more comfortable indoor environment.

Maintenance is a key consideration in the design of the 19XL. The unit features accessible service ports and a simplified access panel, allowing technicians to perform routine maintenance with ease. This proactive design helps ensure the longevity of the system and minimizes downtime, keeping operations running smoothly.

In summary, the Carrier 19XL is an exceptional choice for commercial heating and cooling needs. With its energy-efficient features, advanced technology, and durable construction, it stands out as a reliable solution for businesses looking for sustainable climate control options.
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