A thermostat comprising: a wireless communication circuit configured to receive temperature readings from a remote temperature sensor ; a processor configured to operate in a plurality of modes, wherein the plurality of modes comprises: a first mode ; and a second mode , wherein the processor uses more average power when operating in the second mode than when operating in the first mode ; a memory comprising instructions that, when executed by the processor , cause the processor to: repeatedly transition between operating in the first mode and operating in the second mode , wherein: transitions from operating in the first mode to operating in the second mode are caused at least in part by an expiration of a first time interval ; and the wireless communication circuit is configured to receive one or more of the temperature readings from the remote temperature sensor while the processor is operating in the second mode ; and adjust a length of the first time interval based at least in part on an estimate of how fast the temperature readings from the remote temperature sensor are approaching a threshold temperature , wherein the threshold temperature comprises an upper or lower boundary of a maintenance band around a setpoint temperature. a wireless communication circuit configured to receive temperature readings from a remote temperature sensor ; a processor configured to operate in a plurality of modes, wherein the plurality of modes comprises: a first mode ; and a second mode , wherein the processor uses more average power when operating in the second mode than when operating in the first mode ; a first mode ; and a second mode , wherein the processor uses more average power when operating in the second mode than when operating in the first mode ; a memory comprising instructions that, when executed by the processor , cause the processor to: repeatedly transition between operating in the first mode and operating in the second mode , wherein: transitions from operating in the first mode to operating in the second mode are caused at least in part by an expiration of a first time interval ; and the wireless communication circuit is configured to receive one or more of the temperature readings from the remote temperature sensor while the processor is operating in the second mode ; and adjust a length of the first time interval based at least in part on an estimate of how fast the temperature readings from the remote temperature sensor are approaching a threshold temperature , wherein the threshold temperature comprises an upper or lower boundary of a maintenance band around a setpoint temperature. repeatedly transition between operating in the first mode and operating in the second mode , wherein: transitions from operating in the first mode to operating in the second mode are caused at least in part by an expiration of a first time interval ; and the wireless communication circuit is configured to receive one or more of the temperature readings from the remote temperature sensor while the processor is operating in the second mode ; and transitions from operating in the first mode to operating in the second mode are caused at least in part by an expiration of a first time interval ; and the wireless communication circuit is configured to receive one or more of the temperature readings from the remote temperature sensor while the processor is operating in the second mode ; and adjust a length of the first time interval based at least in part on an estimate of how fast the temperature readings from the remote temperature sensor are approaching a threshold temperature , wherein the threshold temperature comprises an upper or lower boundary of a maintenance band around a setpoint temperature. <EOS>