Heat exchanger transfers heat from a fluid transfer device to the environment, to another object, or to another heat transfer device, and includes one or more insulating segments disposed along the fluid path. The insulated segments thermally interrupt adjacent sections of the fluid transfer device for preventing heat transfer along the length of the fluid transfer device; rather, heat is transferred outwardly away from each thermally interrupted or isolated section of the fluid transfer device. In the case where the thermally isolated section fluid transfer pipe is used for waste heat recovery, a further fluid transfer device may be provided adjacent the fluid transfer device. Each fluid transfer device may have respective thermally isolated sections for maximizing the temperature gradient and, hence, the heat transfer between adjacent fluid transfer devices, and devices for enhancing such maximization.