A device for heating a liquid for a domestic appliance, comprising a main body (1) which is connected to a reservoir of liquid and associated with an additional element (3) covering a surface of the main body (1) in order to define a liquid circulation volume, characterized in that the main body exhibits a thermal inertia which is lower than that of aluminum and in that the additional element (3) has a serigraphed heating resistor on the surface opposite the surface facing the main body (1).