Trane RT-PRC010-EN Heating HotWater or Steam, Heating Modulating Gas, Supply Air Setpoint Reset

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Controls

(VAV Units)

 

 

 

 

Heating: HotWater or Steam

On units with hot water or steam heating, the supply air temperature can be controlled to a heating set point during the Occupied mode.The supply air temperature heating set point and deadband are user-defined at the Human Interface Panel.VAV Occupied heating on hot water and steam heat units is enabled by closing a field-supplied switch or contacts connected to an changeover input on the RTM.

Heating: Modulating Gas

Upon a call for heating, the UCM closes the heating contacts, beginning the firing sequence. First, the heat exchanger combustion blower begins operation. Upon positive proving of combustion airflow, a pre-purge cycle is executed. Then the ignition sequence takes place.

If ignition is not proven, the ignition transformer is de-energized. After a time delay, another pre-purge cycle takes place, followed by another attempt to ignite. If ignition fails a second time, the heating section will be shut down and locked out until manually reset at the unit mounted Human Interface Panel.

As additional heat is required, the air damper opens, increasing the firing rate.

During heating operation, an electronic flame safety control provides continuous flame supervision. If combustion should become unstable for any reason, heating will automatically shut down. After one minute, another 60 second pre-purge and ignition cycle begins.

As the heating requirement is satisfied, the UCM will reduce the combustion air and the firing rate will lower to maintain the desired outlet temperature. When the requirement is fully satisfied, the heating contacts are opened, de- energizing the heat.The specific sequence of operation of the gas heat will depend on the size of the heat exchanger.

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 on outdoor air temperature. Supply air reset adjustment is available from the Human Interface Panel for supply air heating and supply air cooling control.

A

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 a 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

B

reset based on zone temperature

Zone reset is applied to the zone(s) in a building that tend 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 AirTempering

Hot water, steam, and modulating gas units only — When supply air temperature falls below the supply air

temperature deadband low end, the heating valve is modulated open to maintain the set minimum supply air temperature.

3

ZoneTemperature Control

Unoccupied Zone Heating and Cooling

During Unoccupied mode, the unit is operated as a CV unit. Inlet guide vanes and VAV boxes are driven full open.The unit controls zone temperature within the Unoccupied zone cooling and heating (heating units only) deadbands.

Daytime warm-up

This feature is available on all types of heating units. During Occupied mode, if the zone temperature falls to a preset, user-defined zone low limit temperature setpoint the unit is put into Unoccupied mode and Daytime Warm-up is initiated. The system changes over to CV heating (full unit airflow), the VAV boxes are fully opened and full heating capacity is provided until the Daytime Warm-up setpoint is reached.The unit is then returned to normal Occupied mode.

4

Outdoor Air CFM Compensation

The purpose of this feature is to modulate the minimum position of the economizer to compensate for varying unit airflows in VAV units, thereby minimizing the large variation of outdoor air CFM that can occur.The feature allows the user to set (calibrate) the economizer minimum position with inlet guide vanes (or VFD) at 0 percent and at 100 percent. On units with inlet guide vanes (or VFD) and economizer, the minimum position of the economizer is modulated based on inlet guide vane position (or VFD speed).

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RT-PRC010-EN

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Contents 20 75Tons 90 130Tons Introduction American Standard IncContents Features and Benefits Standard FeaturesOptional Features Field Installed AccessoriesFeatures Summary Installation EaseEasy to Service ReliabilitySimplifyingThe Comfort System Integrated Comfort System ICSTracer control points for IntelliPak Rooftops FansWith Inlet GuideVanes Features and Benefits Optimum Building Comfort ControlVariable Frequency Drives VFD Proven DesignThroughTesting and Research Trane 3-DScroll CompressorSimple Design with 70% Fewer Parts LowTorqueVariationApplication Considerations Percent Exhaust System Barometric Relief DampersPanel C Dimensions Horizontal Discharge20 75 tons SXHF, SFHF, SLHF, SSHF, SXHF, SFHF, SLHF, Sshf UnitsTable AC-5 SXHG, SLHG, Sshg Z Dimensions Table AC-4 SXHG, SLHG, Sshg Panel a and B Dimensions2508 17.4 High Capacity Evaporator Coil Corrosive AtmospheresVentilation Override Sequences Natural Gas Heating ConsiderationsAcoustical Considerations Clearance RequirementsFigure AC-4 Unit Placement Duct DesignSelection Procedure DetermineTotalWinter Heating Load Electric Heating SystemGas Heating System Natural Gas HotWater HeatingExhaust Fan Motor Sizing Supply Fan Motor SizingAltitude Corrections Selection Procedure Model Number Description H F C1 1 567 General Data Table GD-1- General Data 20-40Tons20Ton 25Ton 30Ton 40Ton RPMFilters Table GD-2 General Data 50-75Tons 50Ton 55Ton 60Ton 70Ton 75Ton Low Ambient Option Min. Outside AirTemp90Ton 105Ton 115Ton 130Ton Table GD-3 General Data 90-130Tons50% 100% Number/Size/Type 22/FC Table GD-5 ARI Correction Multipliers Table GD-4 ARI Performance DataEER Iplv Performance Adjustment Factors Table PAF-1 Enthalpy of Saturated AIRPerformance 20Ton Data Performance 25Ton Data Performance 30Ton Data Performance 40Ton Data 345 452 265 496 183561 207 451 399 493 302 537 199 429 389 468 292 431 551Performance 50Ton Data Performance 55Ton Data Performance 60Ton Data Performance 70Ton Data AmbientTemperature FFlow Performance 75Ton Data Performance 90Ton Data Performance 105Ton Data Performance 115, 130TonsPerformance Data Table PD-24 Natural Gas Heating CapacitiesTable PD-25- Natural Gas Heating Capacities Table PD-26 Steam Heating Capacities Q/ITD1Table PD-29- 90To 130-Ton Electric Heat AirTemperature Rise Table PD-28 20 to 75-Tons Electric Heat AirTemperature RiseTable PD-30- Electric Heat KW Ranges Table PD-31- HotWater Heating Capacities Q/ITD1 20, 25Tons RPM BHPPressure 4000 1037 1225 12711364 140910 HP 1200 RPM 80% 1100 RPM 6000 883 927 968 1007 1043 1078 22.221400 RPM Wocfm 40% 1300 RPM 25 HP Inches 1200 RPM 50% 20 HP 6000 890 933 974 1012 1049 Table PD-35 Supply Fan PerformanceWITH Inletvanes 30Ton1357 20.45 Dual 18 X 18 Fans Wocfm Entrance Losses Ithout Exhaust15 HP 1200 RPM Fan Curve Limits 1000 RPM 10 HP30.47 40, 50, 55Tons32.36 40, 50, 55Tons 800 14.86 820 1161 32.63 Cfm Total Static Pressure Std 250 500 750 000Inches w.c 60, 70, 75Tons 43.8560, 70, 75Tons 14000 729 800 RPM 20 HP 70% 15 HP 27000 646 690 732 773 808 840 10.71 872 904 13.34 28000 667 710 750 791 826 10.15 85730000 708 749 787 826 10.13 861 897 12.88 928 14.40 957 15.80 98527000 1363 39.85 1388 41.68 1414 43.54 1437 45.26 1461 29000 1375 42.04 1398 43.93 1423 45.91 14451469 49.80 1491 1515 53.66 30000 1382 43.16 1406 45.18 142827000 695 734 770 805 840 904 13.44 935 14.77 28000 718 756 791 825 10.28 858891 12.90 922 14.26 952 15.65 29000 741 778 812 845 897 13.19 928 14.59 958 16.05 9871579 32000 1442 49.55 14641496 55.23 1518 57.33 1541 59.53 1565 37000 1494Performance 105,115,130Tons 1623 76.74 1640 78.95 00 R 15001100 100 900 RP25.35 26.9532.56 1233 34.40 1255 36.26 1277 38.17 46000 1138 26.67 30.40 1216 32.05 1240 33.79 1086 23.371625 76.92 1643 79.30 46000 1624 1641 79.40Table PD-44 Component Static Pressure Drops in.W.G Performance 20 -75Tons DataSFHF/G SEHF/G SLHF/G SSHF/G Performance 90-130Tons Data Table PD-45 Component Static Pressure Drops in.W.GSFHF/G SLHF/G SSHF/GTable PD-46 20-75 -Tons Supply Air Fan Drive Selections Table PD-47 90-130 -Tons Supply Air Fan Drive Selections835 39.71 859 BHP RPM885 44.08 910 46.33 934 48.32 Table PD-50 20-75Tons 100% Exhaust Fan Drive Selections Table PD-51 90-130Tons -100% Exhaust Fan Drive SelectionsTable PD-53 90-130 Tons 50% Exhaust Fan Performance Table PD-52 20-75Tons 50% Exhaust Fan Performance18.97 835 19.86 859 20.87 885 22.05 910 23.18 934 24.17 Table PD-54- 50% Exhaust Fan Drive Selections VAV Units ControlsVAV Units Only Supply Air Setpoint Reset Reset based on outdoor air temperatureReset based on zone temperature ZoneTemperature Control Unoccupied Zone Heating and CoolingCV Units Only CV UnitsHeating Gas Heating -Two-Stage Unoccupied ZoneTemperature Control Cooling and Heating Gas Heating Modulating GasElectric Heating HotWater or Steam HeatingVAV/CV Units Exhaust sequence C Purge sequence DPurge with duct pressure control E Human Interface Panel H.IGeneric Building Automation System odule Gbas Human Interface Panel Main MenuEvaporator Coil Frost Protection Occupied/Unoccupied Switching Dry BulbTemperature Control of EconomizerNight Setback Sensors Occupied/Unoccupied input on the RTMElectrical Service Sizing Dual Source Power units 200VElectrical Data Set 2. Rooftop units with Electric HeatRLA1 LRA 178 21.8 143Table ED-6 -Voltage Utilization Range 48.5 39.0 Motor Hp48.5 39.0 FLADimensional 20 75Tons Figure DD-1 20-75Ton Cooling Only Unit Dimensions Sahf Detail B Covers 40, 60, 70 and 75 TON Units20 & 25 5-8 15/ 16 24-1 3 5/ 8 1-7 9 Sahf 10’-1 7 ’-10 15/ 16 2’-0 ’-6Dimensional 90 130Tons Figure DD-5 90 130Tons Service ClearanceFigure DD-6 90 130Ton Roof Curb Dimensions Section B-B RT-PRC010-ENDimensional Field Installed SensorsConstant CV and VAV Integrated Comfort System SensorsWeights TableW-1 -Approximate OperatingWeights Lbs./KgSL/SS 14740 15380 15930 16080Options OptionsAgency Approval Ambient ControlMiscellaneous Options Electronic Zone Sensors Roof CurbMechanical Specifications GeneralSupply Fan 20 75Ton Units 90 130Ton UnitsControls Unit ControllerPermanent cleanable wire mesh option High efficiency throwaway optionPercent bag filter option Percent cartridge filter optionOutside Air General Manual outside air optionPercent modulating economizer option Ultra low-leak economizer dampers optionAccessories Heating SystemFile Number PL-RT-S*HF/S*HG-20-130TONS-PRC0010-EN-10-2001 Literature Order NumberSupersedes RT-DS-8 05/98 Stocking Location Inland-LaCrosse

RT-PRC010-EN specifications

The Trane RT-PRC010-EN is a prominent model in the line of Trane's packaged rooftop units, designed to offer efficient heating, cooling, and ventilation for commercial applications. Renowned for its robust performance, this unit integrates advanced technologies and superior engineering to meet diverse environmental needs while ensuring energy efficiency and reliability.

One of the key features of the RT-PRC010-EN is its energy-efficient operation. The unit is equipped with variable-speed fans and scroll compressors, which allow for precise control over temperature and airflow. This adaptability not only enhances comfort but also contributes to significant energy savings. The inclusion of high-efficiency cooling coils further optimizes performance, making it an excellent choice for businesses looking to lower their operational costs.

The RT-PRC010-EN model integrates smart controls that allow for seamless integration into building management systems. These controls facilitate real-time monitoring and diagnostics, enabling facility managers to maintain optimum operational efficiency and promptly address any maintenance needs. This technology minimizes downtime and extends the lifecycle of the unit.

Moreover, the unit’s construction is targeted toward resilience and durability. Built with a corrosion-resistant cabinet and extensive insulation, the RT-PRC010-EN can withstand the rigors of various climates, making it suitable for installation across different geographical locations. Its compact design allows for easy installation on rooftops, maximizing space utilization in commercial buildings.

Another standout characteristic is the unit's versatility in application. The RT-PRC010-EN can be tailored to suit a wide range of commercial settings, including retail establishments, educational institutions, and healthcare facilities. Options for various indoor and outdoor configurations enhance its adaptability to specific operational requirements.

In conclusion, the Trane RT-PRC010-EN stands out as an energy-efficient, reliable, and versatile solution for commercial heating and cooling needs. Its advanced features, smart controls, and robust design make it an ideal choice for businesses looking to enhance comfort while minimizing energy expenditures and ensuring operational reliability. Whether dealing with extreme weather conditions or managing indoor air quality concerns, this rooftop unit provides a comprehensive solution tailored to modern commercial requirements.