Safety device against leaks of liquid for liquid-conducting household appliances

A safety device against leaks of liquid for a liquid-conducting household appliance comprises a valve arrangement that can be electrically switched between a closing position and an opening position, to prevent or enable, respectively, a flow of liquid from a liquid-supply source to the household appliance. The device further comprises: - a first pipe (13) impermeable to liquid, for the flow of liquid, - at least one hydraulic unit (12), having a duct for the liquid (30), - a flow sensor in the at least one hydraulic unit (12). The first pipe (13) is connected in fluid communication with the duct (30) and extends longitudinally at least in part within a second pipe (14) that is impermeable to liquid, in such a way that defined between at least part of the first pipe (13) and of the second pipe (14) is a gap (G) having a proximal end and a distal end. The at least one hydraulic unit (12) has a respective hydraulic body (16) that defines the duct (30). The flow sensor is a non-mechanical flow sensor that includes at least two electrical detection elements (42) within the duct (30).