How can I troubleshoot or diagnose what is wrong with my system?
FAQ , Thermostats , Troubleshooting Modified: March 19, 2026
The most basic step towards troubleshooting your system is to check for alerts or warnings that are currently active. Tap the Menu button, and then select the Notifications button to view them.
Notifications are color coded to indicate their importance, with red being service urgent, followed by yellow being service maintenance. After selecting the notification, write down the alert or warning code. You can check what it means here:
What does this alert or notification mean?
If needed, you can contact your dealer (Menu > Lennox Dealer Support Services) or Lennox (at 1-800-9-LENNOX) to get any issue resolved as soon as possible.
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