Trane PKG-PRC002-EN Occupied ZoneTemperature Control, Heating Electric, Supply Air Tempering

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Sequence of

Controls Operation

Zone Temperature Control Unit Sequence Of Operation

1

Occupied ZoneTemperature Control

Cooling/Waterside Economizer During occupied cooling mode, the waterside economizer option and mechanical cooling function to control zone temperature. If the entering condenser water temperature is appropriate to use “free cooling,” the economizer initiates to attempt to satisfy the cooling zone temperature setpoint with the compressors staging on as necessary. Minimum on/off timing of compressors prevents rapid cycling.

Waterside economizing enables when the unit’s entering water temperature is below the unit’s entering mixed air temperature by 4 F plus the user adjustable economizer approach temperature. The approach temperature default is 4 F and is adjustable from 0-9 F at the human interface (HI) panel. Waterside economizing disables when the unit’s entering water temperature is not below the unit’s entering mixed air temperature by at least the water economizer approach temperature. The approach temperature defaults to 4 F and is adjustable from 0-9 F at the HI. The economizer acts as the first stage of cooling. If the economizer is unable to maintain the zone temperature setpoint, the compressor module will bring on compressors as required to meet the setpoint.

If the unit does not include an economizer, only mechanical cooling will operate to satisfy cooling requirements.

Cooling/Airside Economizer During occupied cooling mode, the economizer option and mechanical cooling operate to control zone temperature. If the outside air enthalpy is appropriate for airside economizing or “free cooling,” the economizer initiates to satisfy the cooling zone temperature setpoint with the compressors staging on as necessary. Minimum on/off timing of compressors will prevent rapid cycling.

On units with an airside economizer, a call for cooling will modulate the fresh air

dampers open. The rate of economizer modulation is based on deviation of the zone temperature from setpoint; i.e., the further away from setpoint, the faster the fresh air damper will open. First stage of cooling will start after the economizer reaches full open.

Note that the airside economizer will only function freely if ambient conditions are below the enthalpy control settings or below the return air enthalpy if unit has comparative enthalpy installed. If outside air is not suitable for “economizing,” the fresh air dampers drive to the minimum open position. A field adjustable, factory default setting in the human interface panel orTracer® can provide the input to establish the minimum damper position.

At outdoor air conditions above the enthalpy control setting, only mechanical cooling is used and the fresh air dampers remain at minimum position.

If the unit does not include an airside economizer, only mechanical cooling will operate to satisfy cooling requirements.

Heating: Electric

On units with electric heating, the zone temperature can be controlled to a heating setpoint during the occupied mode by cycling a single stage electric heater. Interface is provided for field supplied single stage electric heat. The zone temperature heating setpoint and deadband are user defined at the human interface panel.

Heating: Hot Water or Steam

On units with hot water or steam heating, the zone temperature can be controlled to a heating setpoint during the occupied mode. The zone temperature heating setpoint and deadband are user defined at the human interface panel.

Supply Air Tempering

For hot water, steam, or electric heat units in the heat mode but not actively heating, if the supply air temperature drops to 10 F (5.5 C) below the occupied zone heating temperature setpoint, one stage of heat will be brought on to maintain a minimum supply air temperature. The unit transitions out of heat mode if the supply air temperature rises to 10 F above the occupied zone heating temperature setpoint.

Auto Changeover

When the system mode is auto, the mode will change to cooling or heating as necessary to satisfy the zone cooling and heating setpoints. The zone cooling and heating setpoints can be as close as 2 F (1.1 C) apart.

2

Unoccupied ZoneTemperature Control

Cooling and Heating

Both cooling and heating modes can be selected to maintain unoccupied zone temperature deadbands. For unoccupied periods, heating, economizer operation, or compressor operation can be selectively locked out at the human interface panel.

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PKG-PRC002-EN

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Contents Commercial Self-Contained DecemberIntroduction Signature Series Self-Contained UnitsContents Features and Benefits Standard Features Optional FeaturesIntegrated Self-Contained Systems Integrated Comfort System ICSLow Torque Variation Proven DesignThroughTesting and ResearchTrane 3-DScroll Compressor Supply Air Ductwork Application Considerations Self-ContainedReturn Air Ductwork Equipment Room Location and OrientationIsolation Recommendations Condenser Water PipingUnit Operating Limits Considerations ApplicationAir Cooled CondenserUnit Capacities Procedure Self-ContainedSelection Waterside Economizer CapacitySelection Example Design Conditions Unit SelectionDescription ProcedureModel Number Self-Contained Model Number DescriptionSelf-Contained Accessory Model Number Description Remote Air-Cooled Condenser Model Number Description General Data TonsTable GD-3. SCWF/SIWF Water-Cooled Self-Contained, 42-80Tons SCRF/SIRF Table GD-4. SCRF/SIRF Air-Cooled Self-ContainedGeneral Data CCRC/CIRCHeating Coil Table GD-7. Self-Contained Heating CoilDrops Data Chart PD-5. Airside Pressure DropPerformance DropsAirside Pressure Heating CoilsDischarge Plenum 20 to 38 Ton Unit 42 to 80 Ton UnitAirside Pressure Airside Economizer with Standard Damper Airside Economizer with Traq Damper Pressure Drop Chart PD-21. Waterside Pressure Drop SCWF/SIWF 35Waterside SCWF/SIWF Performance Water-Cooled Data Table PD-1. CFM Capacity Correction TableTable PD-2. SCWF/SIWF 20 Economizer Full Capacity 8,000 cfm Water-Cooled20 Ton Table PD-3. SCWF/SIWF 20 Economizer Low Capacity 8,000 cfmEntering WaterTemp Entering Air 75 F 85 F 95 F Table PD-6. SCWF/SIWF 22 Economizer Low Capacity 8,800 cfm 22 TonTable PD-5. SCWF/SIWF 22 Economizer Full Capacity 8,800 cfm EnteringWaterTemp Entering Air 75 F 85 F 95 F 25 Ton Table PD-9. SCWF/SIWF 25 Economizer Low Capacity 10,000 cfmEntering Water Temp Entering Air 75 F 85 F 95 F 29 Ton Table PD-12. SCWF/SIWF 29 Economizer Low Capacity 11,600 cfm84.2 32 Ton Table PD-15. SCWF/SIWF 32 Economizer Low Capacity 12,800 cfm94.5 35 Ton Table PD-18. SCWF/SIWF 35 Economizer Low Capacity 14,000 cfm401 320 38 Ton Table PD-21. SCWF/SIWF 38 Economizer Low Capacity 15,200 cfm434 373 42 Ton Table PD-24. SCWF/SIWF 42 Economizer Low Capacity 16,800 cfm403 84.1 46 Ton Table PD-27. SCWF/SIWF 46 Economizer Low Capacity 18,400 cfm83.8 52 Ton Table PD-30. SCWF/SIWF 52 Economizer Low Capacity 20,800 cfm596 471 58 Ton Table PD-33. Scwfsiwf 58 Economizer Low Capacity 23,200 cfm663 571 65 Ton Table PD-36. SCWF/SIWF 65 Economizer Low Capacity 26,000 cfmEntering Water Temp Entering Air 72 Ton Table PD-39. SCWF/SIWF 72 Economizer Low Capacity 28,000 cfm83.7 80 Ton Table PD-42. SCWF/SIWF 80 Economizer Low Capacity 29,800 cfm891 761 Air-Cooled Table PD-45. SCRF/SIRF 25 Gross Cooling Capacity 11,600 cfm Table PD-46. SCRF/SIRF 29 Gross Cooling Capacity 12,800 cfm 30 Ton Table PD-47. SCRF/SIRF 30 Gross Cooling Capacity 14,000 cfmTable PD-48. SCRF/SIRF 35 Gross Cooling Capacity 15,200 cfm 40 Ton Table PD-49. SCRF/SIRF 40 Gross Cooling Capacity 18,400 cfm50 Ton Table PD-50. SCRF/SIRF 50 Gross Cooling Capacity 23,200 cfmTable PD-51. SCRF/SIRF 60 Gross Cooling Capacity 29,800 cfm Performance Air-CooledData60-Ton Table PD-52. HotWater Heating Capacity Self-ContainedHeating Coils Table PD-53. Steam Heating CapacityControls Available Input and Output PointsHuman Interface Panel HI Standard IntelliPak Unit Control FeaturesIntelliPak Unit Features Main menus of the human interface panels areControl Sequences Operation SequenceControls Operation Gbas Binary Outputs Generic Building Automation System Module Gbas OptionGbas Analog Inputs Demand Limiting Binary InputWater Purge Airside OptionsAir-Cooled Condensers Inlet GuideVane ControlHeating Electric Occupied ZoneTemperature ControlUnoccupied ZoneTemperature Control Cooling and Heating Heating Hot Water or SteamSupply Air Tempering Hot Water and Steam Units Only Supply Air Temperature Control Unit Sequence OperationSupply Air Setpoint Reset Standard On All Units Zone SensorControls Options Model Number Digit 6 = A, BAYSENS017Thermometer to indicate temperature in the zone Setpoint thumbwheel for local setpoint adjustment Selection Procedures Electrical DataTable ED-7. CCRC/CIRC Condenser Electrical Data Electrical Data SCWF/SCRFTable ED-6. Single Stage Electric Heat Electrical Data Dimensions Self-Contained Weights Tons Ton Self-ContainedDimensions Self-Contained Weights 40-80 Ton Discharge Dimensions Metric mm Detail B Discharge DimensionsDischarge Dimensions English inches Detail a Electrical ConnectionsDimensions Air-Cooled Weights Condenser Ccrc Unit DimensionsRefrigerant and Electrical Connections DimensionsWeights Front View Looking at Control PanelHot Water Coil Steam CoilPlenum Dimensions Metric mm DimensionsPlenum Dimensions English inches Flexible Horizontal Discharge PlenumAirside Economizer AirsideEconomizer Airside Economizer Dimensions English inches Airside Economizer Dimensions Metric mmZone Sensors Field-InstalledAdjustment Dual Setpoint, Manual/AutomaticProgrammable Night-Setback Sensor Zone Temperature Sensor OnlyFunction Lights Clearances ServiceService/Code Clearance Requirements Self-Contained ModelsTop View CCRC/CIRC 50 Top View CCRC/CIRC 20Top View CCRC/CIRC 35 Table W-2. Unit Weights CCRC/CIRC Dimensions WeightsTable W-1. Unit Weights SCWF/SCRF/SIWF/SIRF Table W-3. Variable Frequency Drive WeightsMechanical Specifications Self-Contained Signature Series Self Contained UnitsMechanical Air-CooledSpecifications Condenser Supply Air Temperature Control with Inlet GuideVanes Mechanical Specifications OptionsAir Volume/Temperature Control Zone Temperature Control Self-Contained OptionsAirside Economizer Interface Comparative Enthalpy ControlStandard Two-Position Damper Interface Airside Economizer Interface with Comparative EnthalpyLow Entering Air Temperature Protection Device Water Flow SwitchService Valves Non-fused Disconnect SwitchCupro-Nickel Condenser Protective Coating CabinetCoils Stainless Steel Drain PanLiterature Order Number

PKG-PRC002-EN specifications

The Trane PKG-PRC002-EN is a groundbreaking packaged rooftop unit designed to meet the diverse needs of commercial and industrial spaces. This model showcases Trane’s commitment to innovation, energy efficiency, and reliability, making it a preferred choice for HVAC professionals and building owners alike.

One of the main features of the PKG-PRC002-EN is its high-efficiency design. This unit leverages advanced technologies to minimize energy consumption while ensuring optimal cooling and heating performance. Its efficient compressor, coupled with enhanced heat exchangers, significantly reduces operating costs and energy bills, aligning with today’s sustainability goals.

The PKG-PRC002-EN features a robust and durable construction, which translates to enhanced longevity and reduced maintenance requirements. Designed for ease of installation, the unit is compact and lightweight, facilitating seamless retrofitting and integration into existing systems. Furthermore, its accessible service panels allow for straightforward maintenance and repairs, thus minimizing downtime and service disruptions.

Equipped with Trane's advanced control technology, the PKG-PRC002-EN offers precise temperature management, ensuring consistent comfort across different zones within a building. The intuitive controls enable users to program schedules and adjust settings based on their specific needs, enhancing comfort while maximizing efficiency.

The model also incorporates advanced filtration options, improving indoor air quality by effectively reducing pollutants and allergens. This focus on health and safety is essential, especially in commercial settings where air quality can significantly impact occupant well-being and productivity.

Another notable characteristic of the PKG-PRC002-EN is its low noise levels during operation, which is essential for maintaining a conducive indoor environment in workplaces, retail spaces, or educational institutions. The unit's design minimizes sound transmission, creating a more pleasant atmosphere for occupants.

In summary, the Trane PKG-PRC002-EN is a highly efficient, reliable, and user-friendly rooftop unit that combines advanced technology with robust construction. Its energy-saving features, superior air quality options, and focus on quiet performance make it an excellent choice for modern commercial HVAC applications, ultimately contributing to sustainable building practices and enhanced occupant comfort.
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