Methods of configuring and controlling hot water supply installations

A hot-water supply installation having a plurality of controllable hot water outlets, the hot-water supply installation including:

• a source of hot water with an outlet having a controllable outflow temperature, the source including an energy storage arrangement containing a mass of energy storage medium to store thermal energy and a heat exchanger coupled to a heat pump or a solar-powered water heater, and a system controller configured to:
• provide to an operator a signal indicative of a future disinfection event;
• receive a response from the operator confirming that the future disinfection event is to be performed;
• and
• in response to receiving the response from the operator:
• increase a hot water supply temperature from a pre-event temperature of less than 60 Celsius to a disinfection temperature;
• provide a signal to the operator to cause the operator to open a first controllable hot water outlet of the plurality of controllable hot water outlets;
• provide a signal to the operator to close the first controllable hot water outlet after a first disinfection period;
• provide a signal to the operator to open a second controllable hot water outlet of the plurality of controllable hot water outlets;
• provide a signal to the operator to close the second controllable hot water outlet after a second disinfection period;
• repeat the providing of each of the signals to the operator to open and then, after a third disinfection period, to close all of the plurality of controllable hot water outlets other than the first and second controllable hot water outlets;
• reduce the hot water supply temperature to the pre-event temperature of less than 60 Celsius from the disinfection temperature;
• and
• indicate to the operator the completion of the future disinfection event.

A method of supplying heated water by a hot water supply system to a water outlet from an appliance including a thermal energy storage, a renewable heat source and a supplementary heat source, the method comprising:

• determining a demand for heated water at the water outlet;
• in response to determining the demand for heated water at the water outlet, heating water to a first target temperature in a range of 40-50 degrees Celsius to provide heated water to a user;
• detecting an elapsed period of time without substantial water usage;
• and
• in response to detecting the elapsed period of time without substantial water usage, performing at least one of the following:
• heating the water in a heat exchanger to a disinfection temperature of at least 60C;
• and/or
• in response to the demand for heated water, initially heating the water leaving the appliance to a disinfection temperature for a period of time sufficient for a pulse of heated water to travel to the water outlet and thereafter reducing the temperature to the first target temperature.