The invention relates to an article for daily use, in particular to a multifunctional heat exchanger, comprising a box body, a tap water pipe, an air-conditioning condensed water pipe and a heating pipe. The multifunctional heat exchanger is characterized in that a heating coil pipe and an air-conditioning condensed water coil pipe are arranged in the box body, and inlet and outlet interfaces for the tap water pipe, inlet and outlet interfaces for the heating pipe and inlet and outlet interfaces for air-conditioning condensed water are respectively arranged on the box body. The invention can greatly reduce the consumption and waste of energy in daily life, can save the electrical energy of an electric water heater in winter instead of utilizing the heat energy of heating, and not only can save the electrical energy but also can utilize heat energy released by an air conditioner in summer; besides, water generated by the heat exchange of the heat exchanger can be used as domestic water for families in winter and summer.