This disclosure is related to devices, systems, and techniques for controlling a temperature of water contained by a water tank. A controller includes a user interface configured to receive one or more user inputs indicative of a request to set a control parameter of the controller and communication circuitry configured to receive, from a user device, an electronic signal. Additionally, the controller includes processing circuitry configured to identify, from the electronic signal, one or more first data packets that include a request to disable an ability to change, based on the one or more user inputs received by the user interface, the control parameter of the controller and in response to receiving the one or more first data packets, disable the ability to change the control parameter of the controller.