Abstract: An elongated heat exchanger of generally tubular shape in which at least one heat exchanger is mounted in the interior thereof. The heat exchanger is composed of an outer tube which may be of a plastic material which forms a sealed chamber and has a pair of ends from which spigots extend. A heat exchanger is mounted within the outer tube and is connected to the spigots at each end so that it extends the length of the outer tube and is sealedly connected to each spigot. The heat exchanger consists of a number of stainless steel tubes (greater than two) each having the same diameter and gently twisted together to form a single heat exchanger. The spigots located at each end of the outer tube thus form manifolds for the tubes of the heat exchanger. A heat exchanger fluid is introduced in the space between the outer tube and the heat exchanger to provide the necessary exchange of heat in the device.