Q: What happens if I loose Internet connectivity for a couple hours? If the outside temperature goes under my compressor lockout temperature, how will the Ecobee know not to run the HP and just use the auxiliary heat?
A: In a scenario where internet weather is lost, the ecobee will engage the heat pump will still operate normally in an attempt to satisfy setpoint. During the 1st hour, the temperatures are recorded to determine if the indoor temperature is rising by at least 0.5F. During the 2nd hour of operation, the indoor temperatures are measured as well. If at the end of hour two the temperature has dropped 0.5F or greater, the heat pump will be locked out until 12pm (noon) the next day. This is based on the assumption that 12 noon is the warmest part of the day and re-engaging the heat pump with carry the least amount of risk. Once the heat pump re-engages, the same run time protocol will apply if internet weather is still not present.
Anytime during the heat pump lockout period, the user can turn the System Mode to "Off" then back to "Heat" to reset the heat pump lockout "flag". Please note, the thermostat will call the Auxiliary heat the entire time the heat pump is locked out, and setpoint not satisfied.