Abstract: A register assembly for augmenting the flow of conditioned air from a central air-conditioning unit to a room includes a fan, a temperature sensor, and a processing means. The fan is operably positioned for increasing air flow through the register assembly. The temperature sensor is for measuring a temperature of air in the register assembly and for outputting a measured temperature signal. The processing means is for: receiving the measured temperature signal; using the measured temperature signal in determining whether the central air-conditioning unit is providing conditioned air to the room; and activating the fan to augment the conditioned air flow if the central air-conditioning unit is providing conditioned air to the room. The processing means also provides drift compensation to prevent unwanted operation of the fan due to temperature drifts.