Carrier 48TCA04---A12 appendix Cooling, Condenser Coil

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To change fan speed:

1.Shut off unit power supply.

2.Loosen belt by loosening fan motor mounting nuts. (See Fig. 5.)

3.Loosen movable pulley flange setscrew. (See Fig. 6.)

4.Screw movable flange toward fixed flange to increase speed and away from fixed flange to decrease speed. Increasing fan speed increases load on motor. Do not exceed maximum speed specified.

5.Set movable flange at nearest keyway of pulley hub and tighten setscrew to torque specifications.

To align fan and motor pulleys:

1.Loosen fan pulley setscrews.

2.Slide fan pulley along fan shaft. Make angular align- ment by loosening motor from mounting.

3.Tighten fan pulley setscrews and motor mounting bolts to torque specifications.

4.Recheck belt tension.

C07075

Fig. 6 - Supply-Fan Pulley Adjustment

Bearings

This fan system uses bearings featuring concentric split locking collars. The collars are tightened through a cap screw bridging the split portion of the collar. The cap screw has a Torx T25 socket head. To tighten the locking collar: Hold the locking collar tightly against the inner race of the bearing and torque the cap screw to 65-70 in-lb (7.4-7.9 Nm). See Fig. 7.

C08121

Fig. 7 - Tightening Locking Collar

Motor

When replacing the motor, also replace the external-tooth lock washer (star washer) under the motor mounting base; this is part of the motor grounding system. Ensure the teeth on the lock washer are in contact with the motor’s painted base. Tighten motor mounting bolts to 120 +/- 12 in-lbs.

Changing fan wheel speed by changing pulleys: The horsepower rating of the belt is primarily dictated by the pitch diameter of the smaller pulley in the drive system (typically the motor pulley in these units). Do not install a replacement motor pulley with a smaller pitch diameter than provided on the original factory pulley. Change fan wheel speed by changing the fan pulley (larger pitch diameter to reduce wheel speed, smaller pitch diameter to increase wheel speed) or select a new system (both pulleys and matching belt(s)).

Before changing pulleys to increase fan wheel speed, check the fan performance at the target speed and airflow rate to determine new motor loading (bhp). Use the fan performance tables or use the Packaged Rooftop Builder software program. Confirm that the motor in this unit is capable of operating at the new operating condition. Fan shaft loading increases dramatically as wheel speed is increased.

To reduce vibration, replace the motor’s adjustable pitch pulley with a fixed pitch pulley (after the final airflow balance adjustment). This will reduce the amount of vibration generated by the motor/belt-drive system.

COOLING

!WARNING

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this warning could cause personal injury, death and/or equipment damage.

This system uses PuronR refrigerant which has higher pressures than R-22 and other refrigerants. No other refrigerant may be used in this system. Gauge set, hoses, and recovery system must be designed to handle Puron refrigerant. If unsure about equipment, consult the equipment manufacturer.

Condenser Coil

The condenser coil is fabricated with round tube copper hairpins and plate fins of various materials and/or coatings (see Model Number Format in the Appendix to identify the materials provided in this unit). The coil may be one-row or composite-type two-row. Composite two-row coils are two single-row coils fabricated with a single return bend end tubesheet.

Condenser Coil Maintenance and Cleaning Recommendation

Routine cleaning of coil surfaces is essential to maintain proper operation of the unit. Elimination of contamination and removal of harmful residues will greatly increase the

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 SectionCondenser Coil Condenser Coil Maintenance and Cleaning RecommendationCooling 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 Indication Error Code Description Orifice ReplacementLED Error Code Description Red LED-Status Orifice Sizes IGC ConnectionsLP Orifice Altitude Compensation* A04-A07Cont. Altitude Compensation* A08-A12 Altitude Compensation* A04-A06 Low NOx Units Troubleshooting Heating SystemMinimum heating entering air temperature 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 Color Code Recommendations RTU-MP Control SystemRecommended Cables 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 Communication Wiring Protocols Connecting Discrete InputsPower Exhaust output 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$er IV Control Modes Outdoor Dry Bulb ChangeoverOutdoor Enthalpy Changeover Return Air Temperature or Enthalpy Sensor Mounting LocationMinimum Position Control Exhaust Setpoint AdjustmentIndoor Air Quality IAQ Sensor Input Thermostats Damper MovementOccupancy Control Demand Control Ventilation DCVEconoMi$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/OffIndoor Air Quality Power ExhaustEconomizer Torque Values Fastener Torque ValuesDemand Limit 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 PerformanceCFM RPM BHP Ton Horizontal SupplyTon Vertical Supply 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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