Carrier 19XL specifications PIC System Functions

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PIC System Functions

NOTE: Throughout this manual, words printed in capital let- ters and italics represent values that may be viewed on the LID. See Table 2 for examples of LID screens. Point names are listed in the Description column. An overview of LID operation and menus is given in Fig. 13-19.

CAPACITY CONTROL Ð The PIC controls the chiller capacity by modulating the inlet guide vanes in response to chilled water temperature changes away from the CON- TROL POINT. The CONTROL POINT may be changed by a CCN network device, or is determined by the PIC adding any active chilled water reset to the ECW (Entering Chilled Water) SET POINT or LCW SET POINT. The PIC uses the PROPORTIONAL INC (Increase) BAND, PROPORTIONAL DEC (Decrease) BAND, and the PROPORTIONAL ECW GAIN to determine how fast or slow to respond. CONTROL POINT may be viewed/overridden on the Status table, Status01 selection.

ENTERING CHILLED WATER CONTROL Ð If this op- tion is enabled, the PIC uses ENTERING CHILLED WATER temperature to modulate the vanes instead of LEAV- ING CHILLED WATER temperature. ENTERING CHILLED WATER control option may be viewed/modi®ed on the Equip- ment Con®guration table, Con®g table.

DEADBAND Ð This is the tolerance on the chilled water/ brine temperature CONTROL POINT. If the water temper- ature goes outside of the DEADBAND, the PIC opens or closes the guide vanes in response until it is within tolerance. The PIC may be con®gured with a 0.5 to 2 F (0.3 to 1.1 C) dead- band. DEADBAND may be viewed or modi®ed on the Equip- ment Service1 table.

For example, a 1° F (0.6° C) deadband setting controls the water temperature within ±0.5° F (0.3° C) of the con- trol point. This may cause frequent guide vane movement if the chilled water load ¯uctuates frequently. A value of 1° F (0.6° C) is the default setting.

PROPORTIONAL BANDS AND GAIN Ð Proportional band is the rate at which the guide vane position is corrected in proportion to how far the chilled water/brine temperature is from the control point. Proportional gain determines how quickly the guide vanes react to how quickly the tempera- ture is moving from CONTROL POINT.

The proportional band can be viewed/modi®ed on the LID. There are two response modes, one for temperature re- sponse above the control point, the other for response below the control point.

The ®rst type is called PROPORTIONAL INC BAND, and it can slow or quicken vane response to chilled water/ brine temperature above DEADBAND. It can be adjusted from a setting of 2 to 10; the default setting is 6.5. PRO- PORTIONAL DEC BAND can slow or quicken vane re- sponse to chilled water temperature below deadband plus control point. It can be adjusted on the LID from a setting of 2 to 10, and the default setting is 6.0. Increasing either of these set- tings will cause the vanes to respond slower than at a lower setting.

The PROPORTIONAL ECW GAIN can be adjusted at the LID display from a setting of 1.0 to 3.0, with a default setting of

2.0.Increase this setting to increase guide vane response to a change in entering chilled water temperature. The propor- tional bands and gain may be viewed/modi®ed on the Equip- ment Service3 table.

DEMAND LIMITING Ð The PIC will respond to the ACTIVE DEMAND LIMIT set point by limiting the open- ing of the guide vanes. It will compare the set point to either COMPRESSOR MOTOR LOAD or COMPRES- SOR MOTOR CURRENT (percentage), depending on how the control is con®gured for the DEMAND LIMIT SOURCE which is accessed on the SERVICE1 table. The default set- ting is current limiting.

CHILLER TIMERS Ð The PIC maintains 2 runtime clocks, known as COMPRESSOR ONTIME and SERVICE ON- TIME. COMPRESSOR ONTIME indicates the total life- time compressor run hours. This timer can register up to 500,000 hours before the clock turns back to zero. The SERVICE ONTIME is a resettable timer that can be used to indicate the hours since the last service visit or any other reason. The time can be changed through the LID to whatever value is desired. This timer can register up to 32,767 hours before it rolls over to zero.

The chiller also maintains a start-to-start timer and a stop- to-start timer. These timers limit how soon the chiller can be started. See the Start-Up/Shutdown/Recycle Sequence sec- tion, page 39, for operational information.

OCCUPANCY SCHEDULE Ð This schedule determines when the chiller is either occupied or unoccupied.

Each schedule consists of from one to 8 occupied/unoccupied time periods, set by the operator. These time periods can be enabled to be in effect, or not in effect, on each day of the week and for holidays. The day begins with 0000 hours and ends with 2400 hours. The chiller is in OCCUPIED mode unless an unoccupied time period is in effect.

The chiller will shut down when the schedule goes to UN- OCCUPIED. These schedules can be set up to follow the building schedule or to be 100% OCCUPIED if the operator wishes. The schedules also can be bypassed by forcing the Start/Stop command on the PIC Status screen to start. The schedules also can be overridden to keep the unit in an OC- CUPIED mode for up to 4 hours, on a one-time basis.

Figure 18 shows a schedule for a typical office building time schedule, with a 3-hour, off-peak cool down period from midnight to 3 a.m., following a weekend shutdown. Example: Holiday periods are unoccupied 24 hours per day. The building operates Monday through Friday, 7:00 a.m. to 6:00 p.m., with a Saturday schedule of 6:00 a.m. to 1:00 p.m., and includes the Monday midnight to 3:00 a.m. weekend cool-down schedule.

NOTE: This schedule is for illustration only, and is not in- tended to be a recommended schedule for chiller operation.

PSIO Software Version 08 and Lower Ð Whenever the chiller is in the LOCAL mode, the chiller will start when the Occupancy Schedule 01 indicates OCCUPIED. When in the CCN mode, Occupancy Schedule 02 is used.

PSIO Software Version 09 and Higher Ð The Local Time Schedule is still the Occupancy Schedule 01. The Ice Build Time Schedule is Schedule 02 and the CCN Default Time Schedule is Schedule 03. The CCN schedule number is de- ®ned on the Con®g table in the Equipment Con®guration table on page 23. The schedule number can change to any value from 03 to 99. If this schedule number is changed on the Con®g table, the operator must use the Attach to Net- work Device table to upload the new number into the Sched- ule screen. See Fig. 17.

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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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