Hot water exchanger

The utility model belongs to the technical field of heat exchangers, and discloses a hot water exchanger. The hot water exchanger is mainly characterized in that a box body which is provided with a hot water liner and a heat exchange water liner up and down is comprised, wherein the hot water liner and the heat exchange water liner are in circulation connection through left and right connection pipelines; a heat exchange pipe group which is composed of a number of heat exchange pipes is arranged in the heat exchange water liner, wherein the diameter of each heat exchange pipe is above 1cm and the heat exchange pipes are connected in parallel; a water inlet and a water outlet of the heat exchange group pass through the heat exchange water liner and the box body through a pipeline section to be connected with a heat source; a cold water inlet which can extend out of the box body through a connection pipe section to be connected with tap water is arranged at the lower part or the side part of the heat exchange w