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Lennox M40 Smart Thermostat Support

The ultimate controller for precise comfort

Lennox M40 Smart Thermostat Support
Description

Welcome to your go-to resource for getting started, setting up your thermostat, and solving common issues. From step-by-step guides to troubleshooting tips, we’ll help you unlock the full potential of your thermostat and keep your home comfort running smoothly.

Your Home Comfort Command Center

Just a few quick steps to get your Lennox M40 Smart Thermostat set up online and to redefine comfort and efficiency for your entire home.

Set Up Wi-Fi

From your thermostat's home screen, go to Menu > Settings > Wi-Fi.

  1. Slide the option to the ON position to enable Wi-Fi.

  2. Press on "Not Connected" to display a list of available access points.

  3. Locate home network and select the network name.

  4. Enter the home Wi-Fi network password and press join to continue. If successful the Thermostat Connectivity Status indicator will show checkmarks across all connections

Create Account / Login

Create Your Account Login Credential on your Lennox Smart Thermostat

  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 reports.

  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.

Enable Advanced Diagnostics

From your thermostat's home screen, go to Menu > Settings > Dealer Support Services

  1. There are two screens under this section, Service Contact Info and Dealer Support Access. If you wish to allow your service provider direct access for troubleshooting your system, then select the following (highly recommended):

  2. Remote Sharing: “ON” - Allows your Lennox Dealer to remotely evaluate the status of your system to ensure optimal performance.

  3. Advanced Diagnostics & Troubleshooting: “ON/ALWAYS” - You will always give authorization to your Lennox Dealer to troubleshoot your system remotely. “OFF” - You will not give authorization to your Lennox Dealer to troubleshoot your system and address system performance remotely.

  4. Alerts and Notifications: “ON” - Allows your Lennox Dealer to receive updates when your system needs maintenance.

  5. Note: All three options must be toggled on for Advanced Diagnostics & Troubleshooting to function.

Download the Lennox Home App

  1. Search for the “Lennox Smart Thermostat App” in the Apple App Store or on Google Play, and download to your smartphone or tablet.

  2. From your home screen, go to Menu > User Account and enter your credentials.

  3. If you already have an account and are connecting multiple thermostats, select “Existing Account” and use your credentials to connect them.

Key Features and Tools

Knowing the details of a few key features will make both you and your home smarter.

Adjusting the 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. If Perfect Temp* is enabled, you’ll see one dial that allows you to set your desired temperature.

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.

One-Touch Away Mode

Overrides your regular programming schedule with a single touch and sets back your heating and cooling set points to save energy.

Smart Home Integration

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 now enabled by Matter.

smart-home-integration.png

Smart Away™ Mode

Smart Away™ 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.

1. First activate Smart Away on your thermostat.

2. Enable Smart Away on the mobile app. Go to Menu > Settings > Away and turn on "Smart Away".

3. The GPS distance at which Smart Away detects your smartphone is factory set at a 2-mile radius. To change this, press the "+" or "-" buttons under Smart Away Fence.

*For Smart Away to function properly, location services must be enabled on your mobile device.

Schedule IQ™

Combines with Smart Away™ Mode to learn your routine and create an energyoptimizing schedule of operation.*

To enable Schedule IQ, go to Menu > Schedule > Schedule IQ > Edit. You can set your preferred temperature for up to four time periods per day by sliding the blue and red circles along the line on the touchscreen. Add the Lennox Smart Thermostat App to your smart device and your system will automatically adjust the temperature when you’re away, saving energy and money.

*Smart Away must be turned on in order for Schedule IQ to function.

Comfort

A steady supply of hot water means showers stay warm, dishes get clean, and everyday routines run smoothly without giving it a second thought.

Efficiency

Designed to use energy wisely, Lennox water heaters help reduce energy use and keep utility bills in check while delivering dependable performance.

Smart Technology

Routine-learning technology and app control help make sure hot water is ready when you need it.

Craftsmanship

Build with durable materials and thoughtful engineering, Lennox water heaters are designed for long-lasting performance, including advanced PermaClad glass-lined tanks that help protect against corrosion.

Mode of Operation

With the " MODE " button you can modify the operating mode used by the water heater to reach the set temperature.

Vacation Mode

Use this mode when hot water will not be needed for an extended time (such as a vacation). After the chosen time period Vacation mode will deactivate and the product will operate at its previous setting. Vacation mode is set in the User Menu. In this mode, no heating is performed; antifreeze protection and antibacterial cycle are guaranteed.

Green Mode

Green mode maximizes energy savings by only using the heat pump.

Comfort Mode

Comfort mode maximizes comfort by efficiently using the heat pump and, when needed, the heating element.

Fast Mode

Fast mode allows the device to reach the desired temperature quickly by using heat pump and heating elements.

Boost

Boost mode is a quick activation for the device to reach desired temperature as fast as possible. Once boost is canceled, the device will resume the previous mode set.

* For access to additional features such as Demand Response or Scheduling, please proceed to download the Comfort Link app, which provides a broader experience.

*After download, be sure to utilize your water heater registration credentials to log into the app for a seamless experience. (No need to re-register.)

FAQs

Find answers to common questions about your thermostat from setup and Wi-Fi connection to troubleshooting and energy-saving tips.

How do I setup or create an account?

You can create a Lennox account from either your smart phone or directly on the thermostat. Launch the Lennox Home App and select the Sign up option.

How do I add a thermostat to my account?

To add a thermostat to your account you will need to be standing in front of your Lennox S40 Smart Thermostat and be logged into your Lennox Home App. From your thermostat...

How do I reset my password?

From the thermostat, if you go to  Menu > User Account > Email > Forgot Password > Enter Password  and hit  Accept , you will be able to reset your Lennox S40...

How do I create a Lennox Smart Thermostat account if I had moved into a home that had already registered?

If you have moved into a home with an S40 that is still registered to the previous owner's account, you may re-register this thermostat after unregistering it first. To unregister, go to ...

What information and adjustment settings are displayed on my thermostat screen?

Temperature Settings: Large display with your current indoor temperature (°F or °C). Heating and Cooling Setpoint Indicators (Ball) on the horseshoe dial. Heating and Cooling Setpoint numerical values displayed at the ends...

How do I enable Matter on my thermostat?

Make sure your Lennox Smart Thermostat has been successfully upgraded to version 4.38 and is online. Make sure your thermostat  and  smartphone/controller  are connected to the  same Wi-Fi network . Navigate to...