Carrier Air Conditioner specifications START-UP and Operation, Operating Limitations, Temperature

Page 66

START-UP AND OPERATION

NOTE: Refer to Start-Up Checklist on pages CL-1 to CL-8.

Actual Start-Up — Actual start-up should be done only under supervision of a qualified refrigeration mechanic.

1.Be sure all service valves are open. Units are shipped from factory with suction, discharge, and liquid line service valves closed.

2.Using the Marquee display, set leaving-fluid set point (CSP.1 is Set Point mode under sub-mode COOL). No cooling range adjustment is necessary.

3.If optional control functions or accessories are being used, the unit must be properly configured. Refer to Op- erating Data section for details.

4.Start chilled fluid pump.

5.Turn ENABLE/OFF/REMOTE CONTACT switch to ENABLE position.

6.Allow unit to operate and confirm that everything is func- tioning properly. Check to see that leaving fluid tempera- ture agrees with leaving set point (CSP.1 or CSP.2), or if reset is used, with the control point (CTPT) in the Run Status mode under the sub-mode VIEW.

Operating Limitations

TEMPERATURES (See Table 35) — If unit is to be used in an area with high solar radiation, mounted position should be such that control box is not exposed to direct solar radiation. Exposure to direct solar radiation could affect the temperature switch controlling cooler heaters.

Table 35 — Temperature Limits for Standard Units

Unbalanced 3-Phase Supply Voltage — Never operate a motor where a phase imbalance between phases is greater than 2%. To determine percent voltage imbalance:

 

max voltage deviation

% Voltage Imbalance = 100 x

from avg voltage

 

average voltage

The maximum voltage deviation is the largest difference between a voltage measurement across 2 legs and the average across all 3 legs.

Example: Supply voltage is 240-3-60. AB = 243 v

BC = 236 v AC = 238 v

1. Determine average voltage:

243 + 236 + 238

Average voltage =

3

=7173

=239

2.Determine maximum deviation from average voltage:

(AB) 243 – 239 = 4 v (BC) 239 – 236 = 3 v (AC) 239 – 238 = 1 v

Maximum deviation is 4 v.

3.Determine percent voltage imbalance:

TEMPERATURE

F

C

Maximum Ambient Temperature

125

52

% Voltage Imbalance = 100 x

4

Minimum Ambient Temperature

0

–18

Maximum Cooler EWT*

95

35

Maximum Cooler LWT

70

21

Minimum Cooler LWT†

38

3.3

LEGEND

EWT — Entering Fluid (Water) Temperature

LWT — Leaving Fluid (Water) Temperature

*For sustained operation, EWT should not exceed 85 F (29.4 C).

†Unit requires modification below this temperature.

Low-Ambient Operation — If operating temperatures below 0° F (–18 C) are expected, refer to separate installation instruc- tions for low-ambient operation using accessory Motor- master® III control. Contact your Carrier representative for details.

NOTE: Wind baffles and brackets must be field-fabricated for all units using accessory Motormaster III controls to ensure proper cooling cycle operation at low-ambient temperatures. See Installation Instructions shipped with the Motormaster III accessory for more details.

Brine duty application (below 38 F [3.3 C] LCWT) for chiller normally requires factory modification. Contact your Carrier representative for applicable LCWT range for standard water-cooled chiller in a specific application.

VOLTAGE

Main Power Supply — Minimum and maximum acceptable supply voltages are listed in the Installation Instructions.

239

= 1.7%

This voltage imbalance is satisfactory as it is below the maximum allowable of 2%.

IMPORTANT: If the supply voltage phase imbalance is more than 2%, contact your local electric utility com- pany immediately. Do not operate unit until imbalance condition is corrected.

Control Circuit Power — Electronic control includes logic to detect low control circuit voltage. Acceptable voltage ranges are shown in the Installation Instructions.

MINIMUM FLUID LOOP VOLUME — To obtain proper temperature control, loop fluid volume must be at least 3 gal- lons per ton (3.25 L per kW) of chiller nominal capacity for air conditioning and at least 6 gallons per ton (6.5 L per kW) for process applications or systems that must operate at low ambi- ent temperatures (below 32 F [0° C]). Refer to application information in Product Data literature for details.

FLOW RATE REQUIREMENTS — Standard chillers should be applied with nominal flow rates approximating those listed in Table 36. Higher or lower flow rates are permissible to obtain lower or higher temperature rises. Minimum flow rates must be exceeded to assure turbulent flow and proper heat transfer in the cooler.

Operation below minimum flow rate could subject tubes to frost pinching in tube sheet, resulting in failure of cooler.

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Contents Safety Considerations ContentsContents GeneralIntroduction Unit Sizes and Modular Combinations 30GUN,R Major System ComponentsUnit Sizes and Modular Combinations 30GTN,R Unit Nominal Section a Section B 30GTN,R Tons Unit 30GTN,RControl Module Communication Carrier Comfort Network CCN InterfaceThermistor Designations Status Switches Output RelayPage 24 V Control Schematic, Unit Sizes 24 V Control Schematic, Unit Sizes 080-110, 230B-315B CCN LEN Data Communication Port Main Base Board Operating Data 040-110 130-210Thermistor T3 and T4 Locations Compressor Thermistor Locations T7 and T8 Belden 8205 Regular Wiring Plenum Wiring Alpha 1895 AmericanManufacturer Columbia D6451 Manhattan M13402 M64430 Quabik 6130Compressor Protection Control System Module Sizes Stepper Motor 12 VDC CEPL130351 30GUN,R Part Load Data Percent Displacement, Standard UnitsDisplacement Compressors Approx110, 290B 255A 60 Hz390B 60 Hz 330A/B360B 50 Hz 390B 50 HzB1† A1,B1 A1†,A2,B1 A1*,B1†,B2 Unloaded compressor Two unloaders, both unloaded 170, 270A 190, 290A, 360A/BA1*,B1*,B2 Required Hardware for Additional Unloaders 150-210Head Pressure Control PumpoutPower FAN Arrangement FAN Relay Normal ControlService Test See Both main power Scrolling Marquee DisplayModes GEN.O TestStrt Run Status Mode and Sub-Mode DirectorySUB-MODE Keypad Range Item Expansion Comment Entry View VersService Test Mode and Sub-Mode Directory SUB-MODE Keypad Range Item Expansion Comment Entry TestOuts Temperature Mode and Sub-Mode Directory Pressure Mode and Sub-Mode DirectorySet Point Mode and Sub-Mode Directory SUB-MODE Keypad Range Item Expansion Comment Entry GEN.I Inputs Mode and Sub-Mode DirectoryReading and Changing Chilled Fluid Set Point CrctOutputs Mode and Sub-Mode Directory Configuration Mode and Sub-Mode DirectorySUB-MODE Keypad Range Item Expansion Comment Entry GEN.O CCN OPT1OPT2 EMM240 RsetExample of Temperature Reset Return Fluid Configuration SUB-MODE Keypad Display Item Expansion Comment Entry RsetExample of Configuring Dual Chiller Control Master Chiller Example of Configuring Dual Chiller Control Slave ChillerSUB-MODE Keypad Entry Display Item Expansion Comment Rset SUB-MODE Keypad Display Item Expansion Comment Entry OPT2 Example of Compressor Lead/Lag ConfigurationTime Clock Mode and Sub-Mode Directory SUB-MODE Keypad Entry Item Expansion Comment Range TimeSetting an Occupied Time Schedule Operating Mode and Sub-Mode DirectoryMode no Item Expansion Description Operating ModesAlarms Mode and Sub-Mode Directory Example of Reading and Clearing AlarmsConfiguration Configuring Temperature ResetMode Keypad SUB-MODE Entry ExpansionRED LED Entry Expansion Configuration Configuring Demand Limit DLS2Troubleshooting To 20 mA Demand LimitingPage Alarm and Alert Codes T051FSM By Control Method Cause Code Alert GENERATED?EWT LCWT170 T153T155 T173T205 T203T204 T206Oil Charge ServiceElectronic Components Compressor OIL RequiredCooler Thermistor Locations Plugs Components for Part Number PluggingCondenser Coils Cooler Head Bolt Tightening Sequence Typical Tube SheetCondenser Fan Adjustment Hz Low Noise Fan Option Units Dimension FAN TypePrinted Circuit Board Connector Refrigerant Feed Components Each circuit hasThermistors Temperature Sensors 5K Thermistor Temperature F vs Resistance/Voltage Drop BDrop a 5K Thermistor Temperature C vs Resistance/Voltage Temp Voltage Resistance Drop 200,510 30GTN,R Units Pressure Switch Settings Psig kPaSwitch Cutout CUT-IN 30GUN,R UnitsPRE-START-UP System CheckMaximum Ambient Temperature 125 Temperature Limits for Standard UnitsTemperature START-UP and OperationField Wiring Refrigerant CircuitNominal and Minimum Cooler Fluid Flow Rates ALM CWPHgbps Energy Management Module EMM Wiring Compressor Expansion Board CXB Accessory Wiring Description Status Default Units Point Unit Configuration SettingsOPTIONS1 Options Configuration Description Status Default PointOPTIONS2 Options Configuration Alarmdef Alarm Definition TableAppendix a CCN Tables Resetcon Temperature Reset and Demand Limit Brodefs Broadcast POC Definition TableCircadio Circuit a Discrete Parameters Aunit General Unit ParametersCircaan Circuit a Analog Parameters Description Status Units Point ForceableCircban Circuit B Analog Parameters Circbdio Circuit B Discrete ParametersOptions Unit Parameters Strthour Description Status Units PointDescription Status Units Point Defaults CurrmodsCSM/FSM Equipment Table Type 621H, Block Line Description PointDescription Status Point Appendix B Fluid Drop Pressure Curves Cooler Fluid Pressure Drop Curves 30GUN,GUR040-110Appendix B Fluid Drop Pressure Curves Cooler Fluid Pressure Drop Curves 30GUN,GUR130-210Cooler Pressure Drop KEY Appendix B Fluid Drop Pressure Curves Cooler Fluid Pressure Drop Curves 30GUN,GUR230B-315B Cooler Fluid Pressure Drop Curves 30GTN,GTR040-110 Cooler Fluid Pressure Drop Curves 30GTN,GTR130-210 Appendix B Fluid Drop Pressure Curves Module B 30GTN,GTR230,245 Module B 30GTN,GTR255,290,315 Service Training Call for Free CatalogSTART-UP Checklist for Comfortlink Chiller Systems Remove and use for job file Preliminary InformationEquipment Chiller Model no Preliminary Equipment Check Check box if complete System Fluid Volume in Loop Type System UnitStart-UpUnit Start-Up Ccnb Description Status Units Value CtrlCcna BaudSlct Heating Cooling Setpoint Select CND.P RMT.A All Units
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