1. A method for controlling an HVAC system, the method comprising: controlling the HVAC system to change an ambient temperature from a first temperature to a second, target temperature during a current time interval; during at least a portion of the time interval, computing an aggregate estimated time that represents a time remaining for the ambient temperature to reach the target temperature by computing a first estimated time from a first model, computing a second estimated time from a second model, and computing the aggregate estimated time from the first estimated time and the second estimated time; and displaying the aggregate estimated time on a display device.