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 (UO), 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 (PS) arranged for the detection of presence of a human or animal body in physical proximity to the user outflow (UO) and/or in an outflow direction area from the user outflow (UO) 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 (UO) based on a response or an indication of no presence of a human or animal body in physical proximity to the user outflow (UO) and/or in an outflow direction area from the user outflow (UO); 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 (PS) 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 (UO) when there is a response or an indication from the presence sensor (PS) 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 (UO), 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 (PS) arranged for the detection of presence of a human or animal body in physical proximity to the user outflow (UO) and/or in an outflow direction area from the user outflow (UO) 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 (UO) based on a response or an indication of no presence of a human or animal body in physical proximity to the user outflow (UO) and/or in an outflow direction area from the user outflow (UO); 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 (PS) 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 (UO) when there is a response or an indication from the presence sensor (PS) 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 (PS) 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 (UO) when there is a response or an indication from the presence sensor (PS) 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. <EOS>