Welcome to the Rooftop Revolution

2021 AHR EXPO Innovation Awards Finalist

Introducing our most powerful, most advanced rooftop unit in the industry. An ultra-efficient design delivers complete comfort at the lowest total cost of ownership, while also reducing maintenance and service time.

Model L A, B, and C Box Units

The RTU
Has Been
Reimagined

The new Model L™ rooftops feature the revolutionary Lennox® CORE Unit Controller and advanced variable-speed technology to maximize energy savings. But that’s just the beginning. Premium diagnostic features reduce installation, service and maintenance to provide the lowest total cost of ownership in the industry.

Model L Rooftop Unit

Model L Unit Diagram
Model L Unit Diagram
  1. CORE Control System

    CORE unit controller is designed to accelerate equipment install and service. Standard with all Model L rooftop units, CORE integrates key technologies that lower install costs, drive system efficiency, and enable smarter asset management.

  2. Open integration with Standard BACnet IP and MS/TP

    Open integration and control with standard BACnet IP & MS/TP, LONtalk, thermostats, and all-new wireless sensors empowers customers to choose their own building controls, allowing simple or tailored operation.

  3. Lead Inverter-Driven, Variable Speed Compressor

    Variable-speed compressor matches the load in the space to reduce compressor cycling while delivering superior comfort and efficiency.

  4. DirectPlus™ Blower System (available 3-12.5 tons)

    DirectPlus™ blower system is a fully variable, high-efficiency motor with a direct-mounted, backwards-curved impeller that provides exceptional performance and lower service and operating costs.

  5. Advanced Dehumidification Technologies

    Humiditrol™+ is a modulating hot-gas reheat dehumidification system that can vary the sensible and latent capacity of the Model L unit to dehumidify the space without overcooling it.

  6. Diagnostics and Sensor System

    Diagnostics and sensor package monitors component performance, tracks capacity and efficiency, and alerts when necessary, enabling smart asset management.

  7. Intertwined Tube and Fin Condenser Coil with Independent Refrigeration Circuits

    The copper tube construction, enhanced ripple-edge aluminum fins, flared shoulder tubing connections and silver soldered construction provide exceptional efficiency.

  8. Variable-Speed ECM Outdoor Fans

    Variable-speed outdoor fan modulates to allow for quiet, efficient year-round operation and mechanical cooling operation down to 0°F.

Want more
Model L?

Explore our 3D Product Viewer

Explore in 3D
Core Control System Close-up View

Introducing the Lennox Core Control System

Providing exceptional performance and efficiency, the Lennox Model L™ rooftop units and the CORE Control System utilize optional wireless sensors, a mobile service app and a built-in wireless gateway to deliver the lowest cost of ownership.

The Lennox® CORE Service App replaces a traditional built-in user interface on the CORE Unit Controller and provides guided setup menus for install, test and balance, and network integration. Reports that detail runtimes and service history can be exported from the app. The app also facilitates seamless commissioning of wireless sensors and sensor networks compatible with the CORE Control System.

Connected Services Icon

Connected Service

The CORE Control System reinvents the service process with a wireless mobile service app, making setup and service faster than ever before.

Open Integration

Open Integration

The CORE Unit Controller empowers customers to choose their building controls, allowing simple or tailored operation.

Reliable Performance

Reliable Performance

The CORE Control System uses built-in algorithms to deliver key performance indicators and drive unit components simply and reliably.

Efficiency Optimization Icon

Efficiency Optimization

The CORE Unit Controller optimizes unit operation in real-time by processing advanced sensor inputs, maximizing energy efficiency and space comfort.

The CORE Service App Makes Servicing Simple

Using a built-in wireless gateway on the CORE Unit Controller, The CORE Service App replaces a traditional built-in user interface. Simple guided setup, real-time data readouts and enhanced test functionalities make servicing Lennox rooftop units easier than ever before.

Real-Time Data Readouts

Enhanced test functionality provides real-time sensor readings, trending and reports that enable easy troubleshooting.

Guided Setup

Guided setup with progress indicators, detailed help and exportable summaries drives simple and trouble-free setup, reducing commissioning times over similar systems.

Lennox CORE Service App Lennox CORE Service App

Total Cost of Ownership Calculator

Calculate how much you can save with the Model L compared to similar rooftop units.

Step {{ currentStep }} of {{ totalSteps }}

Describe your organization.

*When compared to the Lennox [Energence RTU] model. The Total Cost of Ownership Calculator (the “Calculator”) was built using third party building simulation software. Although a considerable amount of research has been conducted to create the Calculator, the information provided herein is merely an estimate of potential savings, intended to be informational only, and is subject to change without notice. Actual savings will depend on many factors, including space occupant load, building size, hours of operation, specific geographic location, weather, and other external factors. To receive accurate information, a full building study and simulation may be required. LENNOX INTERNATIONAL INC. (“LII”) MAKES NO WARRANTY OR GUARANTEE OF ANY KIND, EXPRESS OR IMPLIED, REGARDING THE INFORMATION SET FORTH HEREIN OR OTHERWISE PROVIDED THROUGH THE CALCULATOR, INCLUDING WITHOUT LIMITAITON ANY WARRANTY REGARDING ITS ACCURACY, COMPLETENESS, RELIABILITY, OR SUITABILITY, OR ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. SUCH ESTIMATES OF SAVINGS ARE NOT A GUARANTEE OF SAVINGS, AND IN NO EVENT WILL ANY REFUND BE GIVEN IN CONNECTION WITH AN ESTIMATE OR THIS CALCULATOR.

IN NO EVENT WILL LII BE LIABLE FOR ANY DAMAGES, INCLUDING CONSEQUENTIAL, INCIDENTAL, DIRECT, INDIRECT, SPECIAL, PUNITIVE, OR EXEMPLARY DAMAGES, ARISING OUT OF OR IN ANY WAY RELATED TO THE USE OF OR INABILITY TO USE THE CALCULATOR (WHETHER BASED ON CONTRACT, TORT, NEGLIGENCE, STRICT LIABILITY OR OTHERWISE). ANY RELIANCE ON THE CALCULATOR IS STRICTLY AT THE RISK OF THE USER.

What are your building hours?

5
7

Where is your organization located?

How much do you typically spend on electricity?

{{ formatCents(selections.electricitySpend) }} ¢/kWh*

3

35

*Cents per Kilowatt hour

You could save {{ formatDollars(results.savings.total) }} over {{ savingsTimeSpan }} years with the Model L

{{ formatDollars(results.savings.energy * -1) }} More for {{ formatDollars(results.savings.energy * 1) }} Energy + {{ formatDollars(results.savings.service) }} Service Savings*

Contact your Lennox Rep

*When compared to the Lennox [Energence RTU] model. The Total Cost of Ownership Calculator (the “Calculator”) was built using third party building simulation software. Although a considerable amount of research has been conducted to create the Calculator, the information provided herein is merely an estimate of potential savings, intended to be informational only, and is subject to change without notice. Actual savings will depend on many factors, including space occupant load, building size, hours of operation, specific geographic location, weather, and other external factors. To receive accurate information, a full building study and simulation may be required. LENNOX INTERNATIONAL INC. (“LII”) MAKES NO WARRANTY OR GUARANTEE OF ANY KIND, EXPRESS OR IMPLIED, REGARDING THE INFORMATION SET FORTH HEREIN OR OTHERWISE PROVIDED THROUGH THE CALCULATOR, INCLUDING WITHOUT LIMITAITON ANY WARRANTY REGARDING ITS ACCURACY, COMPLETENESS, RELIABILITY, OR SUITABILITY, OR ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. SUCH ESTIMATES OF SAVINGS ARE NOT A GUARANTEE OF SAVINGS, AND IN NO EVENT WILL ANY REFUND BE GIVEN IN CONNECTION WITH AN ESTIMATE OR THIS CALCULATOR.

IN NO EVENT WILL LII BE LIABLE FOR ANY DAMAGES, INCLUDING CONSEQUENTIAL, INCIDENTAL, DIRECT, INDIRECT, SPECIAL, PUNITIVE, OR EXEMPLARY DAMAGES, ARISING OUT OF OR IN ANY WAY RELATED TO THE USE OF OR INABILITY TO USE THE CALCULATOR (WHETHER BASED ON CONTRACT, TORT, NEGLIGENCE, STRICT LIABILITY OR OTHERWISE). ANY RELIANCE ON THE CALCULATOR IS STRICTLY AT THE RISK OF THE USER.

Contact your Lennox Rep to convert to the Model L