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📘 Chapter Title: Commercial Rooftop Unit (RTU)

📄 Rooftop Unit (RTU)Description:

Overview

tc-lcu-rooftop-precedent-clr.png

This

chapter covers the key functions, components, and applications of ACommercial Rooftop UnitUnits (RTU)RTUs) is a —self-contained HVAC system typicallysystems installed on the roof of commercial and industrial buildings. It provides heating, ventilation, and air conditioning (HVAC) by drawing outdoor air, conditioning it (heating or cooling), and then delivering the treated air into the building viarooftops. ductwork.

RTUs are packagedwidely units,used meaningin allcommercial majorsettings components—compressor,like condenser,retail evaporator,stores, blower, filters,offices, and controlschools systems—aredue housedto intheir acompact single cabinet. This makes installationfootprint and maintenanceall-in-one moreheating, convenientcooling, comparedand toventilation split systems.design.

Readers

Keywill Components

learn:

  • Compressor:How CompressesRTUs refrigerantoperate toand facilitatedistribute heatconditioned transfer.air

  • CondenserKey Coilcomponents: & Fan: Releasescompressors, heat fromexchangers, thesupply/exhaust refrigerantfans, to the outside air.economizers

  • EvaporatorTypical Coil:capacities, Absorbsvoltages, heatand fromairflow return air to cool the building.configurations

  • Blower/Fan:Curb Circulatesinstallation conditioned air into the buildingrequirements and drawscrane in return air.considerations

  • Burner or Electric Heat Elements: Provides heating in gas/electric or electric-only models.

  • Filters: Clean the air before it is circulated indoors.

  • Dampers: Regulate outdoor air intake for ventilation or economizer function.

  • Control System: Manages temperature setpoints, fan speeds,Maintenance and economizerservice logic.access best practices

Types

 


Packaged-Rooftop-Unit-RTU-Explained-696x393.png
Figure: Diagram of RTUs

RTU
    with
  • airflow

    Cooling-Only RTUs: Provide only air conditioning; common in warm climates.

  • Gas/Electric RTUs: Use natural gas for heatingpath and electricitykey forinternal cooling.components

     

Heat Pump RTUs: Use refrigerant to both heat and cool via reversing valve.

  • Multizone RTUs: Serve multiple areas of a building with individual temperature control.

    • Applications

    RTUs are commonly used in:

    • Office buildings

    • Retail stores

    • Warehouses

    • Schools

    • Restaurants

    They are preferredDesigned for theirtechnicians, compactAPMs, footprint,and easefacility teams, this chapter includes visuals, example models, and links to video walkthroughs of access, and cost-effective installation, particularly where rooftop space is available and noise concerns are minimal.

    Advantages

    • All-in-one design simplifiesRTU installation and servicing.

      service
      • procedures.
    • It’s

      Saves interior space by mounting equipment on the roof.

    • Economizers can reduce energy consumption by using outdoor airideal for cooling.

      field

    • Modular capacity makes them scalable for larger buildings.

    Limitations

    • Limited to buildings with flat or low-slope roofs.

    • More exposed to weather, requiring proper sealingreference and maintenance.onboarding new team members.

    • Noise and vibration can transfer into the building if not properly isolated.

    Maintenance Considerations

    Regular inspections are critical to RTU performance:

    • Filter changes (monthly or quarterly)

    • Coil cleaning to maintain heat transfer efficiency

    • Belt and motor inspections

    • Controls and sensors calibration

    • Drain pan and condensate line cleaning

    • Split HVAC Systems

    • Air Handling Units (AHUs)

    • Variable Air Volume (VAV) Systems

    • Packaged Terminal Air Conditioners (PTACs)

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