Systems and methods for low voltage detection for a heat pump water heater are disclosed. A current sensor can be used to monitor current supplied to a inductive load, such as a compressor or evaporator fan, of the heat pump water heater. The current sensor can be coupled to a controller which receives and processes information from the current sensor to determine whether a low voltage condition of the heat pump water heater has occurred. An alert can be provided to an installer/user of the heat pump water heater that a low voltage condition has occurred. The controller can also disconnect the heat pump water heater from the power source to prevent damage to the heat pump water heater.