Methods to detect low hot water reserve condition

Abstract

A method of operating a water heater in a load shed mode can include detecting that an upper water heater thermostat control module in a water heater is calling for heat to be provided via an upper heating element of the water heater while the water heater is in a load shed mode of operation wherein a first leg of power to the water heater is decoupled from an input to the upper water heater thermostat control module and responsive to the upper water heater thermostat control module calling for heat, transmitting a signal to end the load shed mode of operation at the water heater so that the first leg of power to the water heater is coupled to the input of the upper water heater thermostat control module so that the upper heating element of the water heater is enabled to heat water responsive to the upper water heater thermostat control module calling for heat.

Dependencies are inferred from the claim text.