Patent ID: 7881831

Claim:
A water heating system comprising: a tank to store water; a temperature sensor positioned to detect a temperature of the water; a temperature control element configured to alter the temperature of the water, the temperature control element having an activated state and a deactivated state; and a controller including a processor and a memory that stores computer instructions that, when executed by the processor, cause the controller to control the temperature of the water based on a first temperature threshold during a first time period by controlling the temperature control element, the first temperature threshold being one of a first plurality of temperature thresholds and the first time period being one of a first plurality of time periods, each time period of the first plurality of time periods including a respective temperature threshold of the first plurality of temperature thresholds, monitor the amount of time that the temperature control element is in at least one of the activated state and the deactivated state during the first time period, determine a second temperature threshold for a subsequent time period, the second temperature threshold being one of a second plurality of temperature thresholds and the subsequent time period being one of a subsequent plurality of time periods, each time period of the subsequent plurality of time periods including a respective temperature threshold of the second plurality of temperature thresholds, each time period of the subsequent plurality of time periods corresponding to a respective time period of the first plurality of time periods, including the first time period corresponding to the subsequent time period, the second temperature threshold being determined based on the monitored amount of time, and control the temperature of the water based on the second temperature threshold during the subsequent time period.