How do i connect a sensor to my s40 thermostat?
FAQ , Thermostats , Troubleshooting Modified: March 19, 2026
Based on the information provided, to connect a sensor to your s40 thermostat, you need to follow these steps: open the lennox s40 smart thermostat app: go to menu. under system select settings. under smart devices select add. please note that the first device must be added by your dealer in order to create the ble network. once the first sensor is added by the contractor, you will be able to add as many sensors as you like on your own. for more detailed information, please refer to the document titled 'request2.pdf' in the lennox tech pubs faqs. if you continue to have trouble connecting the sensor to your s40 thermostat, please contact lennox technical support for further assistance.
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