A heat exchanger has a fluid flow passage having an inlet and an outlet, and with a first plate and a second plate in opposed facing relation to one another. The fluid flow passage is defined by a space between the inner surfaces of the first and second plates. An electrical heating element is outside the fluid flow passage and adjacent to the outer surface of the first plate, such that heat produced by the electrical heating element is transferred through the first plate to the fluid in the fluid flow passage during use of the heat exchanger. In an embodiment, the first plate has an opening to receive a heater plate component including a first plate portion having an inner surface bonded to a turbulence-enhancing insert and an outer surface bonded to the electrical heating element.