supply lines respectively far from the faucet instead of connecting the apparatus to the faucet directly in one embodiment the described apparatus of fig1 a to 1 c is hidden from the sight of the customer and may be operated using a chain or lever connected to activator 70 or instead of activator 70 for the user to operate in one of the embodiments the mechanism 30 described in fig1 b and 1 c is a timer pellet when the activator 70 is pressed as shown in fig1 b and water starts flowing from hot water supply line port 20 to cold water supply line port 10 the mechanism 30 is closed for a preset time such as 1 minute after the preset time expires mechanism 30 extracts pin 60 as shown in fig1 c and shifts valve 40 to its closed position which acts again as a barrier blocking the flow of water from port 20 to port 10 in another embodiment the described mechanism 30 is a rotary piston measuring the flow of water once a preset amount of water has flowed in channel 80 mechanism 30 extracts pin 60 effectively shifting piston 40 to its closed position as described above in one of the embodiments the described apparatus is used with a thermal tap where the apparatus may be fixed between the water supply lines and the thermal tap or may be implemented in the thermal.