Patent ID: 9086703
Filing Date: 2015-07-21
Classification: F24D,F24F,G05D

Abstract:
1. A thermostat, comprising: at least one Heating, Ventilation, and Air Conditioning (HVAC) wire connector configured to receive at least one HVAC wire including at least one call relay wire; a powering circuit, including a rechargeable battery, that is coupled to said at least one call relay wire and configured to provide electrical power to the thermostat by power stealing therefrom, said power stealing including an active power stealing mode in which power is taken from said at least one call relay wire while the thermostat is in a first operating mode in which the thermostat is actively calling for an HVAC function and an inactive power stealing mode in which power is taken from the at least one call relay wire while the thermostat is in a second operating mode in which the thermostat is not actively calling for the HVAC function; wherein said powering circuit is configured to substantially suspend said power stealing for at least a first time interval immediately following a transition from the second operating mode to the first operating mode, said first time interval being sufficiently long to ensure an absence of transient signals that could lead to undesired call relay tripping or untripping; and wherein said powering circuit provides said electrical power to the thermostat during said times of substantially suspended power stealing at least in part by drawing power from said rechargeable battery.