Water heater appliance and methods for anticipating recharge

A method of operating a water heater appliance, the method comprising:

• determining a future standby event for the water heater appliance, the future standby event being a standby event that is anticipated to occur at a future time;
• determining a contemporary depletion state from a plurality of set depletion states, the plurality of set depletion states comprising a steady state and one or more depleted states;
• calculating a recharge period according to a set formula corresponding to the determined contemporary depletion state;
• and
• directing, prior to the future time at which the future standby event is anticipated to occur, the water heater appliance to the steady state based on the recharge period.

A water heater appliance comprising:

• a casing;
• a tank disposed within the casing, the tank defining an inlet and an outlet;
• a first temperature sensor attached to the casing in thermal communication with the tank to detect a lower temperature thereof;
• a second temperature sensor attached to the casing above the first temperature sensor in thermal communication with the tank to detect an upper temperature thereof,
• a heating system in thermal communication with the tank to heat water within the tank;
• and
• a controller in operative communication with the heating system, the controller being configured to initiate a heating cycle, the heating cycle comprising
• determining a future standby event, the future standby event being a standby event that is anticipated to occur at a future time,
• determining a contemporary depletion state from a plurality of set depletion states, the plurality of set depletion states comprising a steady state and one or more depleted states, determining the contemporary depletion state comprising
• detecting a contemporary temperature from the temperature sensor,
• referencing a previous depletion state determination, and
• determining the contemporary depletion state based on the contemporary temperature and the determined previous depletion state,
• calculating a recharge period according to a set formula corresponding to the determined contemporary depletion state, the set formula being a function of the lower temperature and the upper temperature and based on a heating rate of the determined contemporary depletion state, and
• directing, prior to the future time at which the future standby event is anticipated to occur, the water heater appliance to the steady state based on the recharge period.