Carrier 19XL specifications Recycle Restart Delta T

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and go into a RECYCLE mode. If the water/brine tempera- ture is high enough, the start-up sequence continues on to check the guide vane position. If the guide vanes are more than 6% open, the start-up waits until the PIC closes the vanes. If the vanes are closed, and the oil pump pressure is less than 3 psid (21 kPad), the oil pump relay will then be en- ergized. The PIC then waits until the OIL PRESS (Pressure) VERIFY TIME (operator con®gured, default 15 seconds) for oil pressure to reach 18 psid (124 kPad). After oil pressure is veri®ed, the PIC waits 15 seconds, and then the compres- sor start relay (1CR) is energized to start the compressor. Compressor ontime and service ontime timers start and the compressor starts counter and the number of starts over a 12-hour period counter are advanced by one.

Failure to verify any of the requirements up to this point will result in the PIC aborting the start and displaying the applicable pre-start mode of failure on the LID default screen. A pre-start failure does not advance the starts in 12 hours counter. Any failure, after the 1CR relay has energized, re- sults in a safety shutdown, energizes the alarm light, and dis- plays the applicable shutdown status on the LID display.

Shutdown Sequence Ð Shutdown of the chiller can occur if any of the following events happen:

·the STOP button is pressed for at least one second (the alarm light will blink once to con®rm stop command)

·recycle condition is present (see Chilled Water Recycle Mode section)

·time schedule has gone into UNOCCUPIED mode (chiller protective limit has been reached and chiller is in alarm)

·the start/stop status is overridden to stop from the CCN network or the LID

When a stop signal occurs, the shutdown sequence ®rst stops the compressor by deactivating the start relay. A status message of ``SHUTDOWN IN PROGRESS, COMPRES- SOR DEENERGIZED'' is displayed. Compressor ontime and service ontime stop. The guide vanes are then brought to the closed position. The oil pump relay and the chilled water/ brine pump relay are shut down 60 seconds after the com- pressor stops. The condenser water pump will be shut down when the CONDENSER REFRIGERANT TEMP is less than the CONDENSER PRESSURE OVERRIDE minus 5 psi (34 kPa) or is less than or equal to the ENTERING CONDENSER WATER TEMP plus 3° F (2° C). The stop- to-start timer will now begin to count down. If the start-to- start timer is still greater than the value of the start-to-stop timer, then this time is now displayed on the LID.

Certain conditions during shutdown will change this sequence:

·if the COMPRESSOR MOTOR LOAD is greater than 10% after shutdown, or the starter contacts remain energized, the oil pump and chilled water pump remain energized and the alarm is displayed

·if the ENTERING CONDENSER WATER temperature is greater than 115 F (46 C) at shutdown, the condenser pump will be deenergized after the 1CR compressor start relay

·if the chiller shuts down due to low refrigerant tempera- ture, the chilled water pump will stay running until the LEAVING CHILLED WATER is greater than CONTROL POINT, plus 5° F (3° C)

Automatic Soft Stop Amps Threshold (PSIO Soft- ware Version 09 and Higher) Ð The SOFT STOP AMPS THRESHOLD closes the guide vanes of the com- pressor automatically when a non-recycle, non-alarm stop signal occurs before the compressor motor is deenergized.

If the STOP button is pressed, the guide vanes close to a preset amperage percent or until the guide vane is less than 2% open. The compressor will then shut off.

If the chiller enters an alarm state or if the compressor enters a RECYCLE mode, the compressor will be de- energized immediately.

To activate SOFT STOP AMPS THRESHOLD, view the bottom of Service1 table. Set the SOFT STOP AMPS THRESHOLD value to the percentage amps at which the motor will shut down. The default setting is 100% amps (no Soft Stop).

When the SOFT STOP AMPS THRESHOLD is being applied, a status message ``SHUTDOWN IN PROGRESS, COMPRESSOR UNLOADING'' is shown.

Chilled Water Recycle Mode Ð The chiller may cycle off and wait until the load increases to restart again when the compressor is running in a lightly loaded condition. This cycling of the chiller is normal and is known as recycle. A recycle shutdown is initiated when any of the following con- ditions are true:

·when in LCW control, the difference between the LEAV- ING CHILLED WATER temperature and ENTERING CHILLED WATER temperature is less than the RECYCLE SHUTDOWN DELTA T (found in the Service1 table) and the LEAVING CHILLED WATER TEMP is below the CONTROL POINT, and the CONTROL POINT has not increased in the last 5 minutes.

·when ECW CONTROL OPTION is enabled, the difference between the ENTERING CHILLED WATER temperature and the LEAVING CHILLED WATER temperature is less than the RECYCLE SHUTDOWN DELTA T (found in the Service1 table) and the ENTERING CHILLED WATER TEMPERATURE is below the CONTROL POINT, and the CONTROL POINT has not increased in the last 5 minutes.

·when the LEAVING CHILLED WATER temperature is within 3° F (2° C) of the BRINE REFRIG TRIPPOINT

When the chiller is in RECYCLE mode, the chilled water pump relay remains energized so that the chilled water tem- perature can be monitored for increasing load. The recycle control uses RECYCLE RESTART DELTA T to check when the compressor should be restarted. This is an operator- con®gured function which defaults to 5° F (3° C). This value is viewed/modi®ed on the Service1 table. The compressor will restart when:

·in LCW CONTROL the LEAVING CHILLED WATER tem- perature is greater than the CONTROL POINT plus the RECYCLE RESTART DELTA T; or

·in ECW CONTROL, the ENTERING CHILLED WATER temperature is greater than the CONTROL POINT plus the

RECYCLE RESTART DELTA T

Once these conditions are met, the compressor will ini- tiate a start-up, with a normal start-up sequence.

An alert condition may be generated if 5 or more RECYCLE STARTUPs occur in less than 4 hours. This excessive recycling can reduce chiller life. Compressor re- cycling due to extremely low loads should be reduced. To reduce compressor recycling, use the time schedule to shut the chiller down during low load operation or increase the chiller load by running the fan systems. If the hot gas bypass is installed, adjust the values to ensure that hot gas is ener- gized during light load conditions. Increase the RECYCLE RESTART DELTA T on the Service1 table to lengthen the time between restarts.

The chiller should not be operated below design mini- mum load without a hot gas bypass installed on the chiller.

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Contents Start-Up, Operation, and Maintenance Instructions Safety ConsiderationsContents Contents Introduction Abbreviations and ExplanationsRefrigeration Cycle Chiller FamiliarizationMOTOR/OIL Refrigeration Cooling Cycle 19XL Rear View Take-Apart Rabbet Fit Connector Cooler In/Out Temperature SensorsCondenser In/Out Temperature Sensors Cooler Pressure Schrader FittingLubrication Cycle Refrigerant Motor Cooling and Oil Cooling CyclesLubrication System Starting Equipment Unit-Mounted Solid-State Starter OptionalDenitions ControlsMajor PIC Components Panel Locations PIC Component Panel19XL Controls and Sensor Locations Pressure Transducer, TypicalPower Panel with Options Control and OIL Heater Voltage Selector S1General LID Operation and Menus FigSelect − 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 ScreenDescription Range Units Reference Point Name Alarm History LID ScreensExample 1 Ð STATUS01 Display Screen Menu Status SelectExample 2 Ð STATUS02 Display Screen Example 3 Ð STATUS03 Display ScreenExample 4 Ð Setpoint Display Screen MenuExample 5 Ð Configuration Config Display Screen Example 6 Ð LEAD/LAG Configuration Display ScreenECW Control Option ICE Build TerminationExample 7 Ð SERVICE1 Display Screen Example 8 Ð SERVICE2 Display Screen Spare Alert EnableExample 9 Ð SERVICE3 Display Screen Menu ServiceExample 10 Ð Maintenance MAINT01 Display Screen Example 11 Ð Maintenance MAINT02 Display ScreenDischarge Temperature Bearing TemperatureExample 13 Ð Maintenance MAINT04 Display Screen Example 12 Ð Maintenance MAINT03 Display ScreenDescription RANGE/STATUS Units Reference Point Name PIC System Functions Page Protective Safety Limits and Control Settings Capacity Overrides Page Page Lead/Lag Control ECWHgbp 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 Using the Optional Storage Tank and Pumpout Before Initial START-UPJob Data Required 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 C Ð HFC-134a Pressure Ð Temperature FTemperature 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 CodeCharge Refrigerant into Chiller 19XL Chiller Equalization Without PUMP- OUT UnitControl Test Menu Functions Tests to be Devices Tested PerformedRefrigerant Charges 19XL Total Refrigerant ChargeCooler SizeDry Run to Test Start-Up Sequence Initial START-UPCheck Rotation Check Oil Pressure and Compressor Stop Calibrate Motor CurrentOperating Instructions Operator DutiesTo Stop the Chiller Plant Pumpout and Refrigerant Transfer Procedures Operating the Optional Pumpout CompressorTransfer Refrigerant from Storage Tank to Chiller TstatChillers with Isolation Valves Transfer the Refrigerant from Chiller to Storage TankTest After Service, Repair, or Major Leak Ð If General MaintenanceReturn Refrigerant to Normal Operating Conditions Weekly Maintenance Guide Vane Actuator LinkageCheck Safety and Operating Controls Monthly Scheduled MaintenanceTo Change the OIL Compressor Bearing and Gear Mainten Inspect the Heat Exchanger TubesOptional Pumpout System Controls Troubleshooting Guide MAINT01 MAINT02MAINT03 MAINT04Shutdown with ON/OFF/RESET-OFF Timing OUT or Timed OUTNormal or AUTO.-RESTART Recycle ShutdownAutorestart in Progress LOW Chilled Water Normal RUN with RESET, TEMPERATURE, or Demand Compressor Jumpstart and Refrigerant ProtectionOUT-OF-RANGE Sensor Failures Normal RUN Overrides Active AlertsLimited 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 Module Address Control ModulesInput Options Module Processor Module Psio Fig Starter Management Module SMM FigOptions Module Installation Switch Options Setting ModuleTypical Benshaw, Inc. Solid-State Starter internal View Page Page Benshaw, Inc. Solid-State Starter Troubleshooting Guide Problem Probable Causes Area of CorrectionRV1 SCRHeat Exchanger Data Additional Data for Marine WaterboxesCooler CondenserWaterbox Cover Weights CoolersCondensers 1034 kPaCompressor Weights Compressor/Motor WeightsOptional Pumpout System Electrical Data Compressor Fits and Clearances Compressor Assembly Torques Description TorqueFt-lb ``ZCLR COMComm EXTPage CLR Page Chiller Power Panel, Starter Assembly Motor Wiring Schematic Chiller Power Panel, Starter Assembly Motor Wiring Schematic PMR POTGFR 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.

One of the standout features of the Carrier 19XL is its advanced cooling and heating capabilities. The unit utilizes a high-efficiency scroll compressor that ensures a quieter operation and improved reliability. The system can operate across a wide range of temperatures, making it versatile for various climates. Additionally, it offers both cooling and heating options, allowing for year-round comfort.

Energy efficiency is a focal point of the 19XL design. With an impressive Seasonal Energy Efficiency Ratio (SEER) and Heating Seasonal Performance Factor (HSPF), this unit not only helps reduce energy costs but also supports environmental sustainability initiatives. The unit is equipped with environmentally friendly refrigerants, further contributing to lower greenhouse gas emissions.

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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