What happens when the Smart Thermostat is affected by a power outage?

Alarm.com checks the Smart Thermostat (ADC-T2000) power level once per day. If there is a power outage at that time, a notification will be sent to the customer.

A power restoral notification will thus be sent a minimum of 24 hours after the initial power outage occurs. If there is not a power outage during the polling period, no outage will be reported. 

The thermostat will not be able to operate the HVAC system during a power outage.