Carrier 48TCA04---A12 appendix

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When Y2 is energized, the economizer will be modulated to control to a lower supply air setpoint SASP= SATLO2

+3_F If the SAT > SASP + 5_F it will close the economizer to minimum position for 3 minutes, reset the integrator for the economizer, then start modulating the economizer to maintain the SASP after the stage two has been on for 90 seconds. This provides protection for the compressor against flooded starts and allow refrigerant flow to stabilize before modulating the economizer again. By using return air across the evaporator coil just after the compressor has started allows for increased refrigerant flow rates providing better oil return of any oil washed out during compressor start-up.

Routine No. 3: If the OAT > 68_F and the enthalpy is low and the OAT < SPT then the economizer will open to 100% and compressors 1 and 2 will be cycled based on Y1 and Y2 inputs respectively. If any of these conditions are not met the economizer will go to minimum position.

If there is no call for heating or cooling, the economizer, if available, will maintain the SASP at 70_F.

Heating — For gas or electric heat, HS1 and HS2 outputs will follow W1 and W2 inputs respectively. The fan will also be turned on if it is configured for electric heat.

Heating may also be energized when an IAQ sensor installed and has overridden the minimum economizer damper position. If the OAT < 55_F and an IAQ sensor is installed and the IAQ minimum position > minimum damper position causing the SAT to decrease below the SPT - 10_F, then the heat stages will be cycled to temper the SAT to maintain a temperature between the SPT and the SPT + 10_F.

Auxiliary Relay configured for Exhaust Fan — If the Auxiliary Relay is configured for exhaust fan (AUXOUT

=1) in the CONFIG configuration table and Continuous Power Exhaust (MODPE) is enable in the SERVICE configuration table then the output (HS3) will be energized whenever the G input is on. If the MODPE is disabled then output will be energized based on the Power Exhaust Setpoint (PES) in the SETPOINT table.

Indoor Air Quality — If the optional indoor air quality (IAQI) sensor is installed, the PremierLink controller will maintain indoor air quality within the space at the user-configured differential setpoint (IAQD) in the CONFIG configuration table. The setpoint is the difference between the IAQI and an optional outdoor air quality sensor (OAQ). If the OAQ is not present then a fixed value of 400 ppm is used. The actual space IAQ setpoint (IAQS) is calculated as follows:

IAQS = IAQD + OAQ (OAQ = 400 ppm if not present)

As air quality within the space changes, the minimum position of the economizer damper will be changed also thus allowing more or less outdoor air into the space depending on the relationship of the IAQI to the IAQS. The IAQ algorithm runs every 30 seconds and calculates IAQ minimum position value using a PID loop on the IAQI deviation from the IAQS. The IAQ minimum position is then compared against the user configured

minimum position (MDP) and the greatest value becomes the final minimum damper position (IQMP). If the calculated IAQ Minimum Position is greater than the IAQ maximum damper position (IAQMAXP) decision in the SERVICE configuration table, then it will be clamped to IAQMAXP value.

If IAQ is configured for low priority, the positioning of the economizer damper can be overridden by comfort requirements. If the SAT < SASP -8_F and both stages of heat are on for more then 4 minutes or the SAT > SASP + 5_F and both stages of cooling on for more then 4 minutes then the IAQ minimum damper position will become 0 and the IQMP = MDP. IAQ mode will resume when the SAT > SASP -8_F in heating or the SAT < SASP + 5_F in cooling.

If the PremierLink controller is configured for 1 stage of heat and cool or is only using a single stage thermostat input, this function will not work as it requires the both Y1 and Y2 or W1 and W2 inputs to be active. In this application, it is recommended that the user configure IAQ priority for high.

If IAQ is configured for high priority and the OAT < 55_F and the SAT < (SPT -10_F), the algorithm will enable the heat stages to maintain the SAT between the SPT and the SPT + 10_F.

CCN SENSOR MODE — When the PremierLink controller is configured for CCN control, it will control the compressor, economizer and heating outputs based its own space temperature input and setpoints or those received from Linkage. An optional CO2 IAQ sensor mounted in the space or received through communications can also influence the economizer and heating outputs. The PremierLink controller does not have a hardware clock so it must have another device on the CCN communication bus broadcasting time. The controller will maintain its own time once it has received time as long as it has power and will send a request for time once a minute until it receives time when it has lost power and power is restored. The controller will control to unoccupied setpoints until it has received a valid time. The controller must have valid time in order to perform any broadcast function, follow an occupancy schedule, perform IAQ pre-occupancy purge and many other functions as well. The following sections describe the operation for the functions of the PremierLink controller.

Indoor Fan — The indoor fan will be turned on whenever any one of the following conditions are met:

SIf the PremierLink controller is in the occupied mode and ASHRAE 90.1 Supply Fan is configured for Yes in the CONFIG table. This will be determined by its own internal occupancy schedule if it is programmed to follow its local schedule or broadcast its local schedule as a global schedule, or following a global schedule broadcast by another device.

S If PremierLink controller is in the occupied mode and ASHRAE 90.1 Supply Fan is configured for No and there is a heat or cool demand (fan auto mode)

48TC

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Contents Safety Considerations Table of ContentsRoutine Maintenance Unit Arrangement and AccessGeneral What to do if you smell gasSeasonal Maintenance Supply Fan Belt-Drive Supply FAN Blower SectionCooling Condenser Coil Maintenance and Cleaning RecommendationCondenser Coil Routine Cleaning of Coil Surfaces Periodic Clean Water RinseRemove Surface Loaded Fibers One-Row CoilCleaning the Evaporator Coil Refrigerant System Pressure Access PortsEvaporator Coil Evaporator Coil Metering DevicesPuronr R-410A Refrigerant To Use Cooling Charging ChartsRefrigerant Charge No ChargeSize Designation Nominal Tons Reference Cooling Charging ChartsCooling Charging Charts C08229 C08437 C08438 C08439 Problem Cause Remedy Cooling Service AnalysisTroubleshooting Cooling System Condenser-Fan AdjustmentConvenience Outlets CompressorSystem Smoke DetectorsController Unit Connect Primary TransformerSmoke Detector Locations SensorFiop Smoke Detector Wiring and Response Completing Installation of Return Air Smoke SensorSensor Alarm Test Procedure Sensor Alarm TestController Alarm Test Sensor and Controller TestsDirty Controller Test Procedure Controller Alarm Test ProcedureDirty Sensor Test Procedure To Configure the Dirty Sensor Test OperationDetector Cleaning Troubleshooting GAS Heating System Protective DevicesCompressor Protection Relief DeviceNatural Gas Supply Line Pressure Ranges Fuel Types and PressuresNatural Gas Manifold Pressure Ranges Liquid Propane Supply Line Pressure RangesCombustion-Air Blower Flue Gas PassagewaysCheck Unit Operation and Make Necessary Adjust- ments Cleaning and AdjustmentBurners and Igniters Main BurnersBurner Ignition Limit SwitchLED Error Code Description Orifice ReplacementLED Indication Error Code Description Red LED-Status Orifice Sizes IGC ConnectionsCont. Altitude Compensation* A08-A12 Altitude Compensation* A04-A07LP Orifice Minimum heating entering air temperature Troubleshooting Heating SystemAltitude Compensation* A04-A06 Low NOx Units Problem Cause Remedy Heating Service AnalysisIGC IGC Board LED Alarm CodesPremierLink Controller Premierlinkt ControlPremierLink Wiring Schematic 55 Space Temperature Sensor Wiring PremierLink Sensor Usage Space Sensor Mode56 Internal Connections Thermostat ModeLctb Indoor CO2 Sensor 33ZCSENCO2 Connections PremierLink Filter Switch Connection Recommended Cables RTU-MP Control SystemColor Code Recommendations RTU-MP Multi-Protocol Control Board RTU-MP System Control Wiring Diagram Outputs RTU-MP Controller Inputs and OutputsRTU-MP T-55 Sensor Connections Space Temperature SPT SensorsIAQ Sensor SEN J4-2 COM J4-3 24 VAC Power Exhaust output Connecting Discrete InputsCommunication Wiring Protocols RTU-MP Troubleshooting LEDs on the RTU-MP show the status of certain functions LEDsTroubleshooting Alarms BACnet MS/TP AlarmsRTU-MP Driver Modbus Basic Protocol TroubleshootingManufacture Date Code Name MeaningEconoMi$er IV Component Locations Economizer SystemsEconoMi$er IV Wiring EconoMi$er IV Input/Output Logic EconoMi$erOutdoor Air Lockout Sensor Supply Air Temperature SAT SensorEconoMi$er IV Control Modes Outdoor Dry Bulb ChangeoverOutdoor Enthalpy Changeover Return Air Temperature or Enthalpy Sensor Mounting LocationIndoor Air Quality IAQ Sensor Input Exhaust Setpoint AdjustmentMinimum Position Control Thermostats Damper MovementOccupancy Control Demand Control Ventilation DCVEconoMi$er IV Sensor Usage CO2 Sensor ConfigurationEconoMi$er IV Preparation Differential EnthalpyWiring Diagrams 48TC Typical Unit Wiring Diagram Power A06, 208/230-3-60 48TC Unit Wiring Diagram Control A06 START-UP, General PRE-START-UPMain Burners CoolingHeating Ventilation Continuous FanSTART-UP, Premierlink Controls Field Service TestSTART-UP, RTU-MP Control Perform System Check-OutConfiguration Input InputsSpace Sensor Type Input 1 FunctionBase Unit Controls Cooling, Units Without Economizer Operating SequencesHeating, Units Without Economizer Cooling, Unit With EconoMi$erPremierLink Control Heating With EconoMi$er48TC Available Cooling Stages OAT ≤ SPT 48TC 48TC RTU-MP Sequence of Operation Loadshed Command Gas and Electric Heat UnitsLinkage Modes SchedulingLocal Schedule Always Occupied Default OccupancyBACnet Schedule BAS On/OffEconomizer Power ExhaustIndoor Air Quality Demand Limit Fastener Torque ValuesTorque Values Model Number Nomenclature Appendix I. Model Number SignificanceSerial Number Format Position NumberPhysical Data Cooling Tons Appendix II. Physical Data48TC*A08 48TC*A09 48TC*A12 Physical Data CoolingPhysical Data Heating LOW General Fan Performance Notes Appendix III. FAN PerformanceTon Vertical Supply Ton Horizontal SupplyCFM RPM BHP Medium Static Option High Static Option 48TC**05 48TC**05 Phase Ton Horizontal Supply1493 48TC**05 Phase Ton Vertical Supply1506 14861482 48TC**0648TC**06 Phase Ton Vertical Supply 48TC**06 Phase Ton Horizontal Supply48TC**07 Phase Ton Horizontal Supply1124 11071103 1143 1122 11621099 4971116 1093 11331263 5791247 1273Unit MOTOR/DRIVE Motor Pulley Turns Open Combo Pulley AdjustmentIFM Appendix IV. Electrical DataRange RLA LRA TypeFLA Appendix IV. Electrical DataEFF at IFM RangeRLA LRA FullNOM IFM No P.E Combustion PowerFAN Motor Exhaust Type DISC. SizeNOM Unbalanced 3-Phase Supply VoltageWiring Diagrams Appendix V. Wiring Diagram List48TC*A04 Outdoor Circuiting Appendix VI. Motormaster Sensor LocationsCatalog No 48TC---2SM 48TC*A09/12 Outdoor CircuitingPreliminary Information Unit START-UP Checklist

48TCA04---A12 specifications

The Carrier 48TCA04---A12 is a high-efficiency rooftop air conditioning unit designed for commercial and industrial applications. Known for its reliability and performance, this model features advanced technologies that cater to diverse climate control needs.

One of the standout features of the Carrier 48TCA04---A12 is its excellent energy efficiency, which adheres to the stringent standards set by the U.S. Environmental Protection Agency. The unit utilizes a highly efficient scroll compressor combined with state-of-the-art heat exchanger technology, allowing it to operate with minimal energy consumption while providing powerful cooling capabilities.

The unit comes equipped with a robust and durable design, built to withstand various environmental conditions. Its weather-resistant cabinet is constructed from high-quality materials, ensuring long-lasting performance even in harsh climates. Additionally, the unit features a galvanized steel structure with a powder-coated finish, further enhancing its resistance to corrosion and wear.

In terms of technologies, the Carrier 48TCA04---A12 incorporates advanced controls that promote optimal performance. The unit supports Carrier's smart connectivity options, facilitating remote monitoring and adjustments via smart devices. This feature ensures convenient energy management and allows maintenance teams to access performance data, leading to proactive service interventions.

Another important characteristic of this unit is its quiet operation. The design includes sound-reducing insulation and a well-engineered airflow system, minimizing noise levels to create a more comfortable indoor environment. This is particularly important for commercial spaces such as offices and retail environments, where a tranquil atmosphere is critical for customer satisfaction and productivity.

The Carrier 48TCA04---A12 also offers diverse application flexibility, making it suitable for various locations, from small retail stores to large warehouses. With several tonnage options available, users can select a model that perfectly aligns with their specific cooling needs. Additionally, the unit can be easily integrated with existing HVAC systems, providing a seamless solution for upgrading or retrofitting older installations.

To sum up, the Carrier 48TCA04---A12 rooftop air conditioning unit stands out due to its exceptional energy efficiency, durable construction, advanced technology, and quiet operation, making it a reliable choice for commercial and industrial cooling solutions. Its flexibility and smart technology integrations ensure that it meets a wide range of climate control requirements effectively.
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