How can i restart an s40 if the thermostat is black?
FAQ , Thermostats , Troubleshooting Modified: March 19, 2026
Based on previous interactions with similar issues, you can restart your lennox s40 smart thermostat by following these steps: go to the thermostat and press the three lines. tap on 'settings'. tap on 'system settings'. tap on 'advanced settings'. tap on 'restart', and press the restart button. press the yes button.
For more information or a visual representation of steps please reference our user guide here
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