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Lennox S40 Smart Thermostat

The ultimate controller for precise comfort

Lennox S40 Smart Thermostat Lennox S40 Smart Thermostat Lennox S40 Smart Thermostat Lennox S40 Smart Thermostat
Lennox S40 Smart Thermostat

Welcome to your Home Comfort Command Center. Unlike most smart thermostats, the Lennox S40 Smart Thermostat is more than a temperature regulator. It's the command center for your entire system, with the incredible ability to monitor sensors throughout your home and in all your equipment. From detecting air pollutants and customizing comfort by room to providing maintenance and service reminders, it will even automatically alert you if your system goes out of tune and allow you to remotely share diagnostics with your local Lennox dealer. The Lennox S40 Smart Thermostat not only provides the most precise and perfect air, it also gives peace of mind.

This truly digital product is part of a fully communicating home comfort system. Sensors in the equipment allow the thermostat to diagnose issues and automatically make system adjustments to more precisely and efficiently maintain temperature, humidity and air quality. Complement your system with our suite of technologically advanced accessories to more precisely and efficiently maintain the temperature and air quality in your home. The Lennox Smart Air Quality Monitor is the only monitor of its kind that can detect air pollutants and trigger air cleaning on demand. Add on Lennox Smart Room Sensors to more evenly balance temperatures across rooms, plus the Lennox Wireless Extender to nearly double the connection coverage area and ensure you get the most from your communicating equipment. Altogether, it's the most advanced accessories package available that delivers next-level perfect air.

Complete control at home or away. Remote control of your home environment is just one touch or voice command away with the Lennox S40 Smart Thermostat.

Getting Started

S40 Quick start guide
S40 User Guide

Getting Started

Setup Wi-Fi

  • 1. From the thermostat's home screen, go to Menu > Settings > Wi-Fi.
  • 2. Slide the option to the ON position to enable Wi-Fi.
  • 3. Press on "Not Connected" to display a list of available access points.
  • 4. Locate home network and select the network name.
  • 5. Enter the home Wi-Fi network password and press join to continue. If successful the Thermostat Connectivity Status indicator as illustrated below will show checkmarks across all connections.
S40 Quick start guide

S40 User Guide

Step 1 of 4

Step 2

Create Your Account Login Credential on your Lennox Smart Thermostat

Once your Lennox Smart Thermostat is connected to Wi-Fi, you're ready to create an account and take control. If you already have an account, simply sign in using your email and password. From your thermostat's home screen, go to Menu > User Account.
  • 1: Select “Create New Account.”
  • 2: Enter account details such as your first and last name, phone, email address, and password.
  • 3: Select whether you want to receive e-mail updates, reminders and performance report.
  • 4. Select allow your dealer to receive notifications (highly recommended).
  • 5. Select agree to EULA.
  • 6. Enter your information and select Next. Enter your country/region, address, city, state, and zip code.
  • 7. Select Create Account.

Step 2 of 4

Step 3

Adjusting Temperature

Tap your thermostat's home screen to go to the horseshoe-shaped dial where you can adjust the temperature in either of two ways:
  • 1. Using the Horseshoe Dial - Touch the red circle to adjust the temperature in heating mode and the blue circle to adjust it in cooling mode.
  • 2. Tap “Heat To” or “Cool To” Icons - Tap either of the “Heat To” or “Cool To” icons where a detailed horseshoe dial will allow you to select the perfect heating or cooling temperature setpoint.
If Perfect Temp is enabled, you'll see one dial that allows you to set your desired temperature.

Step 3 of 4

Step 4

Download the Lennox Smart Thermostat App

Complete control at home or away. Remote control of your home environment is just one touch or voice command away with the Lennox S40 Smart Thermostat. Monitor temperatures and schedules from anywhere in the world using the Lennox Smart Thermostat app on your smartphone or tablet. Available on the App Store and Google Play
Google Play Google Play
Apple Play Apple App Store

Step 4 of 4

SPECIFICATIONS

  • Take your home comfort system to the next level

    Complement your home comfort system with our suite of technologically advanced accessories to more precisely and efficiently maintain the temperature and air quality in your home (Smart Room Sensor and Smart Air Quality Monitor – sold separately)

  • Complete control at home or away

    Remote control of your home environment is just one touch or voice command away with the Lennox S40 Smart Thermostat. Monitor temperatures and schedules from anywhere in the world using the Lennox Smart Thermostat app on your smartphone or tablet.

  • Smart Home Integration

    The Lennox S40 Smart Thermostat effortlessly integrates with a range of smart home devices—from premium smart home systems like Control4 to popular virtual assistants like Amazon Alexa and Google Assistant.

  • Precise Comfort® Plus

    Works with Lennox digital variable-capacity equipment to offer the highest level of comfort and overall system performance

  • PureAir™ S compatible

    The PureAir™ S Purification System is equipped with smart and sensing features that make maintaining your system a breeze. Built-in sensors monitor the life of both the filter and the purifier UVA light so you don't have to. When it's time to change the filter or the purifier, the PureAir™ S lets you know through your Lennox S40 Smart Thermostat.

  • Weather Screen Savers

    Themed screen savers on the 7" HD color touchscreen are designed with graphics that tell you what weather conditions are like outside

  • Weather-On-Demand

    Provides current outdoor temperature and a five- or seven-day forecast

  • Basic Alerts

    Automatically emails alerts to you and your preferred Lennox dealer if the system needs service or maintenance

  • Advanced Alerts

    Monitors all of the system components and uses advanced diagnostics to identify the issue

  • Climate IQ® Technology

    Monitors humidity levels indoors and outdoors and automatically adjusts compressor speed to maximize dehumidification performance. DLSC or Elite Series digital variable-speed air conditioner or heat pump required.

  • Digitally intelligent for precision and efficiency

    This truly digital product is part of a fully communicating home comfort system. Sensors in the equipment allow the thermostat to diagnose issues and automatically make system adjustments to more precisely and efficiently maintain temperature, humidity and air quality

  • Energy Savings

    Programmable schedules save energy when no one is home

  • Filter Reminder

    Reminds homeowner when it is time to change the filter

  • Automatic Changeover

    Automatically changes between heating and cooling systems to keep the house comfortable in spring and fall

  • Color Touchscreen

    Large, easy-to-use display with adjustable brightness

  • Run-Time Report

    Shows how long the heating or cooling system has run

  • Smart AwayTM Mode

    Smart AwayTM Mode uses the GPS in your smartphone to detect when you're leaving, and automatically adjusts the temperature to a more energy-efficient setting. If you or a family member returns home, Smart Away then returns your system to a normal schedule and comfortable temperature.

  • Schedule IQTM Technology

    Uses homeowner inputs and Smart AwayTM geo-fencing capabilities to learn your routine and create a schedule that maintains comfort when the home is occupied and help save energy when it's not

  • Feels LikeTM Setting

    Set it like you want it. Feels LikeTM considers the humidity levels to deliver the temperature you want to feel, rather than the temperature you set

  • Auto (Perfect Temp)

    Like Auto Changeover, the system automatically decides between heating and cooling, but requires just one setpoint

  • Video Screen Savers

    HD Video Screen Savers automatically change to reflect current outdoor weather conditions

  • Custom Backdrops feel like home

    Upload your own photo backdrop to the S40 screen using your smartphone and the Lennox Smart Thermostat App

  • Humidity Control

    Works with whole-house humidity-control systems to adjust the home's humidity level

  • Allergen Defender

    Monitors the air quality and pollen levels of local ZIP code and automatically turns the fan on to clean the home's air when outdoor levels are high

  • Performance Reports

    Performance reports give you historical data on your system's operation and performance. It tracks temperature ranges, how long the system runs each day and more. Opt-in to have reports emailed directly to you each month.

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