A external water circle device for water heater and combination with water heater thereof

The utility model provides an external water circle device for water heater and combination with water heater thereof, which comprises an outer shell, the inlet channel, outlet conduit, return water pipe, water pump and controller, the inlet channel, outlet conduit runs through the shell respectively, the inlet channel is used for connecting from the beginning the cold water entry of the mouth of a river and water heater, outlet conduit is used for connecting with the hot water export of water spot with the water heater, return water pipe one end is stretched out the shell and is entered the mouth as the return water, the other end is connected with the inlet channel, the water pump concatenates to be connected on return water pipe and with the controller electricity. Since through inlet channel, outlet conduit and return water pipe can make this device and water heater, with constituting a closed loop circuit between the water spot, the water pump is realized the hydrologic cycle and produces the rivers signal making the water heater start -up arrive the settlement temperature with the hot -water heating in the closed loop circuit in closed loop circuit to realize that user's start goes out hydrothermal function promptly.