A method for performing a hot water pasteurization procedure in a water distribution system being a water recirculating system comprising: a water supply, a heating source, at least one temperature sensor, a flow path for water with a user outflow, and a control unit for operation of the water distribution system, said temperature sensor being connected to the control unit, wherein the control unit also is connected to at least one presence sensor arranged for the detection of presence of a human or animal body in physical proximity to the user outflow and/or in an outflow direction area from the user outflow and wherein the control unit is arranged to drive a hot water pasteurization procedure of at least a portion of the flow path and out from the user outflow based on a response or an indication of no presence of a human or animal body in physical proximity to the user outflow and/or in an outflow direction area from the user outflow; and wherein said method comprising: - controlling that no human or animal body is positioned in a risk zone by using said at least one presence sensor which is connected to the control unit driving the pasteurization procedure; and - flowing hot water in the at least part of the flow path for water and out from the user outflow when there is a response or an indication from the presence sensor that no human or animal body is positioned in said risk zone; - setting an intended time for flowing hot water based on the temperature measured in said temperature sensor, by use of a timer unit connected to the control unit. a water supply, a heating source, at least one temperature sensor, a flow path for water with a user outflow, and a control unit for operation of the water distribution system, said temperature sensor being connected to the control unit, wherein the control unit also is connected to at least one presence sensor arranged for the detection of presence of a human or animal body in physical proximity to the user outflow and/or in an outflow direction area from the user outflow and wherein the control unit is arranged to drive a hot water pasteurization procedure of at least a portion of the flow path and out from the user outflow based on a response or an indication of no presence of a human or animal body in physical proximity to the user outflow and/or in an outflow direction area from the user outflow; and wherein said method comprising: - controlling that no human or animal body is positioned in a risk zone by using said at least one presence sensor which is connected to the control unit driving the pasteurization procedure; and - flowing hot water in the at least part of the flow path for water and out from the user outflow when there is a response or an indication from the presence sensor that no human or animal body is positioned in said risk zone; - setting an intended time for flowing hot water based on the temperature measured in said temperature sensor, by use of a timer unit connected to the control unit. - controlling that no human or animal body is positioned in a risk zone by using said at least one presence sensor which is connected to the control unit driving the pasteurization procedure; and - flowing hot water in the at least part of the flow path for water and out from the user outflow when there is a response or an indication from the presence sensor that no human or animal body is positioned in said risk zone; - setting an intended time for flowing hot water based on the temperature measured in said temperature sensor, by use of a timer unit connected to the control unit.