Trane RT-PRC031-EN manual Controls Variable Air Volume VAV Only

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Controls

Variable Air Volume (VAV) Only

Figure 11. IntelliPak™ II Control Panel

Bypass control is offered to provide full nominal airflow in the event of drive failure.

Supply Air Static Pressure Limit

The opening of VAV terminals, and the amount of supply air provided by the inlet guide vanes, or variable frequency drive are coordinated during start up and transition to/from Occupied/Unoccupied modes to prevent over pressurization of the supply air ductwork.

However, if for any reason the supply air pressure exceeds the user- defined supply air static pressure limit that was set at the Human Interface Panel, the supply fan/VFD is shut down and the inlet guide vanes

VAV Units Only

Note: When noted in this sequence “Human Interface Panel,” the reference is to both the unit mounted and remote mounted Human Interface Panel. All setpoint adjustments can be accomplished at the unit or Remote Human Interface Panel.

When in any position other than full open, the vanes pre-spin intake air in the same direction as supply fan rotation. As the vanes approach the full-closed position, the amount of “spin” induced by the vanes increases at the same time that intake airflow and fan horsepower diminish. The inlet guide vanes will close when the supply fan is shut down, except during night setback.

(if included) are closed.

The unit is then allowed to restart three times. If the over pressurization condition occurs on the third time, the unit is shut down and a manual reset diagnostic is set and displayed at the Human Interface Panel and BAS/Network.

Supply Air Temperature Controls

Supply Air Pressure Control

Inlet Guide Vanes Control

Inlet guide vanes are driven by a modulating 0-10 vdc signal from the Rooftop Module (RTM). A pressure transducer measures duct static pressure, and the inlet guide vanes are modulated to maintain the supply air static pressure within an adjustable user-defined range.

The range is determined by the supply air pressure setpoint and supply air pressure deadband, which are set through the Human Interface Panel or BAS/Network.

Inlet guide vane assemblies installed on the supply fan inlets regulate fan capacity and limit horsepower at lower system air requirements.

Variable Frequency Drive (VFD) Control

Variable frequency drives are driven by a modulating 0-10 vdc signal from the Rooftop Module (RTM). A pressure transducer measures duct static pressure, and the VFD is modulated to maintain the supply air static pressure within an adjustable user-defined range.

The range is determined by the supply air pressure setpoint and supply air pressure deadband, which are set through the Human Interface Panel or BAS/Network.

Variable frequency drives provide supply fan motor speed modulation. The drive will accelerate or decelerate as required to maintain the supply static pressure setpoint. When subjected to high ambient return conditions the VFD will reduce its output frequency to maintain operation.

Cooling/Economizer

During Occupied cooling mode of operation, the economizer (if available) and cooling are used to control the supply air temperature. The supply air temperature setpoint and deadband are user-defined at the Human Interface Panel.

The supply air temperature setpoint may be user-defined from the BAS/ Network. If the conditions of the outside air is appropriate to use “free cooling,” the economizer will be used first to attempt to satisfy the supply air setpoint; then if required the hydronic valve will be modulated to maintain supply air temperature setpoint.

On units with economizer, a call for cooling will modulate the fresh air dampers open. The rate of economizer modulation is based on deviation of the supply air

RT-PRC031-EN

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Contents IntelliPak II Air Handlers Introduction Table of Contents Controls Cabinet Mechanical Features and BenefitsStandard Features Features and Benefits Optional Features Reliability Features and Benefits Field Installed AccessoriesFeatures Summary Installation and ServiceSimplifying the Comfort System Features and Benefits Application FlexibilityIntegrated Comfort with Trane Tracer LCI Optimum Building Comfort Control Features and BenefitsInteroperability Statitrac Statitrac Direct Space Building Pressurization ControlVariable Frequency Drives VFD Supply Fans with Inlet Guide VanesSupply Air Temperature Controls Supply Air Pressure Control Controls Variable Air Volume VAV OnlyHeating Controls Variable Air Volume VAV OnlySupply Air Setpoint Reset Zone Temperature Control Gas Heating Two-Stage Controls Constant Volume CV OnlyOccupied Zone Temperature Control HeatingHot Water or Steam Heating Controls Constant Volume CV Only Auto ChangeoverUnoccupied Zone Temperature Control Cooling and HeatingEmergency Override Controls VAV and CVSpace Pressure Control Statitrac Morning Warm-up OptionsVentilation Override Module VOM Controls VAV and CVHuman Interface Panel Main Menu Human Interface Panel HIGeneric Building Automation System Module Gbas 0-5 vdc Night Setback Sensors Generic Building Automation System Module Gbas 0-10 vdcChilled Water Coil Freeze Stat Steam and Hot Water Coil Freeze AvoidanceTimed Override Activation Dry Bulb Temperature Control of EconomizerOccupied/Unoccupied input on the RTM Trane Tracer or BAS SystemTwinning Humidification ControlLonTalk Building Automation System Return Fan ControlAdvantages Applications ConsiderationsExhaust/Return Fan Options Application RecommendationsApplications Considerations Supply and Return Airflow ConfigurationsCartridge Supply Airflow ConfigurationReturn Airflow Configuration With BagAcoustical Considerations Corrosive AtmospheresVentilation Override Sequences Natural Gas Heating ConsiderationsClearance Requirements Unit PlacementExternal Piping Enclosure Duct DesignProtecting Hydronic Coils From Freezing Selection Procedure Selection Procedure Altitude Corrections Exhaust Fan Motor SizingReturn Fan Motor Sizing Unit Electrical RequirementsDigit 7 Chilled Water Coil FIN Series Model Number DescriptionDigit 20 System Control Selection Model Number DescriptionDigit 38 Belt Guards Burglar BARS/MARINE Lights General Data General Data All dimensions in inchesGeneral Data Standard Damper Optional Low Leak Damper Gas Heat Inputs/Input RangesEconomizer Outdoor Air Damper Leakage at rated airflowi Inputs MBH Input MBH Range MBHGas Heating Capacity Altitude Correction Factors Performance Adjustment FactorsWet Bulb Temperature Btu per Pound Enthalpy of Saturated AirDB F WB F Performance Data-Chilled Water Coil CapacitiesChilled Water Coil Capacities-2 Row 5W Chilled Water Coil Capacities-4 Row W Performance Data-Chilled Water Coil CapacitiesChilled Water Coil Capacities-6 Row WD Chilled Water Coil Capacities-8 Row WD Total Static Pressure Std Air Supply Fan Performance Standard CFM Casing a1644 Supply Fan w/o IGV 931 Supply Fan Performance Standard CFM -Casing B1117 Supply Fan Performance Standard CFM-Casing B 749 Supply Fan Performance Standard CFM Casing C1019 Std Air Total Static PressurePerformance Data Supply Fan with Inlet Guide Vanes Performance Data Supply Fan with Inlet Guide Vanes Supply Fan Performance Standard CFM-Casing a Supply Fan Performance Standard CFM Casing B 1093 1600 RPM 1500 RPM 779 1021 1283 Negative Static Pressure Std Air Performance Data-Exhaust FanStatic PresureInWC Performance Data-Exhaust Fan237i Wocfm 415 Exhaust Fan Performance Standard CFM-Case C 32 Fan0 R P M Return Fan Performance Standard CFM-Case a 36.5 Fan Performance Data-Return FanReturn Fan Performance Performance Data-Return FanReturn Fan Performance Standard CFM-Case B and Case C 40 Fan Return Fan Performance Electric Heat kw Ranges Electric Heat Air Temperature RisePerformance Data-Heat Natural Gas Heating Capacities1Properties of Steam Performance Data-HeatHot Water Coil Heating Capacities Q/ITD Steam Coil Heating Capacities Q/ITDComponent Static Pressure Drops in. H2O Chilled Water Coil Airside Pressure Drop in H20Filters Prefilter High Low PD Cartridge Bag FiltersCartridge Filters Throw Temp Hi Temp Away Prefilter Casing Drive No Supply Air Fan Drive Selections15 HP 20 HP 25 HP 30 HP 40 HP Drive No Horse Power HP Low Casing StdExhaust Air Fan Drive Selections Return Air Fan Drive SelectionsSet 2. Cooling with Electric Heat Electrical Service SizingElectrical Data Set 1. Cooling with Gas Heat Air Handling UnitsElectrical Service Sizing Data-Motors Nominal Tons Voltage 460 575 FLA Add 90-150 Electrical DataVoltage Utilization Range Unit VoltageUnit Top/Front View Dimensional DataReturn Exhaust Unit Height Fan Casing Dimensional DataUnit Dimensions In.-One-Piece Unit Supply Opening Blank Casing Gas Heat Section Downflow/Horizontal Airflow Configuration DimensionsOpening Electrical Entry Details Piping Chilled Water Piping Locations Exh Box Minimum Required ClearanceUnit Option Selection Door Swing Ft. Standard Minimum Required Clearance Ft ControlCross Member Location Blank Casing Section Dimensions Blank Casing SectionBlank Casing Section Field Installed Sensors Variable Air Volume VAV Field Installed Sensors Constant Volume CV Field Installed Sensors VAV and CV Wireless Zone Sensor Wall or Duct Mount CO2 Zone Sensors Component Weights Lbs WeightsApproximate Operating Weights Lbs Weights Size Wt lbs Control Box Main 454 Convenience Outlet Roof Curb WeightsInstalled Shipping Casing Blank Weight Options Filters OptionsSystem Control Fresh AirMiscellaneous Options Agency ApprovalElectronic Zone Sensors Field Installed AccessoriesRoof Curb Electrical System Mechanical SpecificationsGeneral Air Handling System Mechanical Specifications Cooling System Chilled Water CoilWater Valve External Piping EnclosureMechanical Specifications Filters Percent Modulating Exhaust Fan Option Mechanical SpecificationsExhaust Air No Relief StandardFresh Air Mechanical Specifications Return AirHeating System CO2 Sensing Page RT-PRC031-EN
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