How do I create a Lennox Smart Thermostat account if I have moved into a home that has already registered the thermostat?
FAQ , Thermostats , Troubleshooting Modified: March 19, 2026
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 Menu > Settings > (Advanced Settings) Unregister System > Unregister and select Yes. Now you will be able to re-register the device to your account.
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