Pro T705 thermostat: heat kicks on when it drops below 64.5 despite it being set to kick on at 60
It's probably &quot;adaptive intelligent recovery&quot;.  That is, the thermostat learns about the building's heat loss and capacity of the heating system.   So if you want the wake up temp at 73  by 8:00 AM, the tstat &quot;learns&quot; that it takes 2 hours (just an example) to get there, so it turns the heating system on at 6:00.  From your graph (impressive, BTW), it doesn't seem like it's turning the system on during the night, only in the early morning to get to temp by the time you set as &quot;wake up&quot; temp. What you might be seeing is the space just hadn't cooled down to 60 before it was &quot;time to turn on the system&quot; to get you to your 73 degree set point by when you wanted it.