Trane PKG-PRC002-EN manual Supply Air Temperature Control Unit Sequence Operation

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Sequence of

Controls Operation

Supply Air Temperature

Control Unit Sequence Of

Operation

1

Occupied Supply Air Temperature Control

Cooling/Waterside Economizer

During occupied cooling mode, the waterside economizer option and mechanical cooling are used to control the supply air temperature. The supply air temperature setpoint and deadband are user defined at the human interface panel. Waterside economizing enables when the units entering water temperature is below the units 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 HI. Waterside economizing disables when the units entering water temperature is not below the units entering mixed air temperature by at least the water economizer approach temperature.

The economizer acts as the first stage of cooling. If the economizer is unable to maintain the supply air 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 satisfy cooling requirements.

Cooling/Airside Economizer During occupied cooling mode of operation, the airside economizer option and mechanical cooling are used to control the supply air temperature. The supply air temperature setpoint and deadband are user-defined at the human interface panel. If the temperature of the mixed air is appropriate to use “free cooling,” the economizer initiates to satisfy the supply air setpoint. Then if required, the mechanical cooling stages on to maintain supply air temperature setpoint. Minimum on/off timing of the mechanical cooling prevents 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 discharge temperature from setpoint, i.e., the further away from setpoint, the faster the fresh air damper will open. First stage of cooling initiates after the economizer reaches full open.

Note that the airside economizer is only allowed to function freely if ambient conditions are below the setpoint control settings or below the return air enthalpy, if unit has the comparative enthalpy option. 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 setpoint or comparative enthalpy control setting, only mechanical cooling is used and the fresh air dampers remain at minimum position.

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

Heating: Hot Water or Steam

On units with hot water or steam heating, the supply air temperature can be controlled to a heating setpoint during the occupied mode. The supply air temperature heating setpoint and deadband are user defined at the human interface panel.VAV occupied heating on hot water and steam heat units is initiated by closing a field-supplied switch or contacts connected to a changeover input on the unit’s RTM module board .

Supply Air Setpoint Reset

Supply air reset can be used to adjust the supply air temperature setpoint on the basis of a zone temperature or outdoor air temperature. Supply air reset adjustment is available from the human interface panel for supply air heating and supply air cooling control.

Reset based on outdoor air temperature Outdoor air cooling reset is sometimes used in applications where the outdoor temperature has a large effect on building load. When the outside air temperature is low and the building cooling load is low, the supply air setpoint can be raised, thereby preventing subcooling of critical zones. This reset can

lower usage of mechanical cooling, thus savings in compressor kW, but an increase in supply fan kW may occur.

Outdoor air heating reset is the inverse of cooling, with the same principles applied.

For both outdoor air cooling reset and heating reset, there are three user defined parameters that are adjustable through the human interface panel. •Beginning reset temperature •Ending reset temperature •Maximum amount of temperature reset

Reset based on zone temperature Zone reset is applied to the zone(s) in a building that tends to overcool or overheat. The supply air temperature setpoint is adjusted based on the temperature of the critical zone(s). This can have the effect of improving comfort and/or lowering energy usage. The user- defined parameters are the same as for outdoor air reset.

Supply Air Tempering (Hot Water and Steam Units Only)

When supply air temperature falls below the supply air temperature deadband low end, the heating valve modulates open to maintain the minimum supply air temperature setpoint.

2

Unoccupied Supply AirTemperature Control Zone Heating and Cooling During unoccupied mode, the unit operates to maintain zone temperature with fan cycling as needed for building load.VAV boxes drive full open. However, unit airflow modulation control operates to maintain duct static setpoint. The unit controls zone temperature within the unoccupied zone cooling and heating (heating units only) deadbands.

Daytime Warmup

During occupied mode, if the zone temperature falls to a preset, user- defined zone low limit temperature setpoint, the unit is put into daytime warmup. The system changes over to CV heating, theVAV boxes drive full open. However, unit airflow modulation control operates to maintain duct static setpoint, and full heating capacity is provided until the daytime warmup setpoint is reached. The unit is then returned to normal occupied mode.

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Contents December Commercial Self-ContainedSignature Series Self-Contained Units IntroductionContents Features and Benefits Optional Features Standard FeaturesIntegrated Comfort System ICS Integrated Self-Contained SystemsProven DesignThroughTesting and Research Trane 3-DScroll CompressorLow Torque Variation Equipment Room Location and Orientation Application Considerations Self-ContainedReturn Air Ductwork Supply Air DuctworkCondenser Water Piping Isolation RecommendationsUnit Operating Limits Condenser ApplicationAir Cooled ConsiderationsWaterside Economizer Capacity Procedure Self-ContainedSelection Unit CapacitiesUnit Selection Selection Example Design ConditionsSelf-Contained Model Number Description ProcedureModel Number DescriptionSelf-Contained Accessory Model Number Description Remote Air-Cooled Condenser Model Number Description Tons General DataTable GD-3. SCWF/SIWF Water-Cooled Self-Contained, 42-80Tons Table GD-4. SCRF/SIRF Air-Cooled Self-Contained SCRF/SIRFCCRC/CIRC General DataTable GD-7. Self-Contained Heating Coil Heating CoilDrops Drops Chart PD-5. Airside Pressure DropPerformance DataHeating Coils Airside Pressure20 to 38 Ton Unit 42 to 80 Ton Unit Discharge PlenumAirside Pressure Airside Economizer with Standard Damper Airside Economizer with Traq Damper Chart PD-21. Waterside Pressure Drop SCWF/SIWF 35 WatersidePressure Drop SCWF/SIWF Table PD-1. CFM Capacity Correction Table Performance Water-Cooled DataTable PD-3. SCWF/SIWF 20 Economizer Low Capacity 8,000 cfm Water-Cooled20 Ton Table PD-2. SCWF/SIWF 20 Economizer Full Capacity 8,000 cfmEntering WaterTemp Entering Air 75 F 85 F 95 F 22 Ton Table PD-5. SCWF/SIWF 22 Economizer Full Capacity 8,800 cfmTable PD-6. SCWF/SIWF 22 Economizer Low Capacity 8,800 cfm EnteringWaterTemp Entering Air 75 F 85 F 95 F Table PD-9. SCWF/SIWF 25 Economizer Low Capacity 10,000 cfm 25 TonEntering Water Temp Entering Air 75 F 85 F 95 F Table PD-12. SCWF/SIWF 29 Economizer Low Capacity 11,600 cfm 29 Ton84.2 Table PD-15. SCWF/SIWF 32 Economizer Low Capacity 12,800 cfm 32 Ton94.5 Table PD-18. SCWF/SIWF 35 Economizer Low Capacity 14,000 cfm 35 Ton401 320 Table PD-21. SCWF/SIWF 38 Economizer Low Capacity 15,200 cfm 38 Ton434 373 Table PD-24. SCWF/SIWF 42 Economizer Low Capacity 16,800 cfm 42 Ton403 84.1 Table PD-27. SCWF/SIWF 46 Economizer Low Capacity 18,400 cfm 46 Ton83.8 Table PD-30. SCWF/SIWF 52 Economizer Low Capacity 20,800 cfm 52 Ton596 471 Table PD-33. Scwfsiwf 58 Economizer Low Capacity 23,200 cfm 58 Ton663 571 Table PD-36. SCWF/SIWF 65 Economizer Low Capacity 26,000 cfm 65 TonEntering Water Temp Entering Air Table PD-39. SCWF/SIWF 72 Economizer Low Capacity 28,000 cfm 72 Ton83.7 Table PD-42. SCWF/SIWF 80 Economizer Low Capacity 29,800 cfm 80 Ton891 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 Table PD-47. SCRF/SIRF 30 Gross Cooling Capacity 14,000 cfm 30 TonTable PD-48. SCRF/SIRF 35 Gross Cooling Capacity 15,200 cfm Table PD-49. SCRF/SIRF 40 Gross Cooling Capacity 18,400 cfm 40 TonTable PD-50. SCRF/SIRF 50 Gross Cooling Capacity 23,200 cfm 50 TonPerformance Air-Cooled Data60-TonTable PD-51. SCRF/SIRF 60 Gross Cooling Capacity 29,800 cfm Table PD-53. Steam Heating Capacity Self-ContainedHeating Coils Table PD-52. HotWater Heating CapacityAvailable Input and Output Points ControlsMain menus of the human interface panels are Standard IntelliPak Unit Control FeaturesIntelliPak Unit Features Human Interface Panel HISequence Controls OperationControl Sequences Operation Demand Limiting Binary Input Generic Building Automation System Module Gbas OptionGbas Analog Inputs Gbas Binary OutputsInlet GuideVane Control Airside OptionsAir-Cooled Condensers Water PurgeHeating Hot Water or Steam Occupied ZoneTemperature ControlUnoccupied ZoneTemperature Control Cooling and Heating Heating ElectricSupply Air Temperature Control Unit Sequence Operation Supply Air Setpoint ResetSupply Air Tempering Hot Water and Steam Units Only Model Number Digit 6 = A, BAYSENS017 Zone SensorControls Options Standard On All UnitsThermometer to indicate temperature in the zone Setpoint thumbwheel for local setpoint adjustment Electrical Data Selection ProceduresElectrical Data SCWF/SCRF Table ED-6. Single Stage Electric Heat Electrical DataTable ED-7. CCRC/CIRC Condenser Electrical Data Ton Self-Contained Dimensions Self-Contained Weights TonsDimensions Self-Contained Weights 40-80 Ton Detail a Electrical Connections Detail B Discharge DimensionsDischarge Dimensions English inches Discharge Dimensions Metric mmCcrc Unit Dimensions Dimensions Air-Cooled Weights CondenserFront View Looking at Control Panel DimensionsWeights Refrigerant and Electrical ConnectionsSteam Coil Hot Water CoilFlexible Horizontal Discharge Plenum DimensionsPlenum Dimensions English inches Plenum Dimensions Metric mmAirside EconomizerAirside Economizer Airside Economizer Dimensions Metric mm Airside Economizer Dimensions English inchesDual Setpoint, Manual/Automatic Field-InstalledAdjustment Zone SensorsZone Temperature Sensor Only Function LightsProgrammable Night-Setback Sensor Self-Contained Models ServiceService/Code Clearance Requirements ClearancesTop View CCRC/CIRC 20 Top View CCRC/CIRC 35Top View CCRC/CIRC 50 Table W-3. Variable Frequency Drive Weights Dimensions WeightsTable W-1. Unit Weights SCWF/SCRF/SIWF/SIRF Table W-2. Unit Weights CCRC/CIRCSignature Series Self Contained Units Mechanical Specifications Self-ContainedMechanical Air-CooledSpecifications Condenser Self-Contained Options Mechanical Specifications OptionsAir Volume/Temperature Control Zone Temperature Control Supply Air Temperature Control with Inlet GuideVanesAirside Economizer Interface with Comparative Enthalpy Comparative Enthalpy ControlStandard Two-Position Damper Interface Airside Economizer InterfaceNon-fused Disconnect Switch Water Flow SwitchService Valves Low Entering Air Temperature Protection DeviceStainless Steel Drain Pan Protective Coating CabinetCoils Cupro-Nickel CondenserLiterature 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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