Patent attributes
The invention relates to a condensation heat exchanger. The inventive heat exchanger consists of two co-axial helicoidal tube bundles which are positioned end-to-end, one of said bundles (2a) serving as a primary exchanger and the other (2b) serving as a secondary exchanger. Each of the aforementioned bundles comprises a tube and/or a group of flat tubes which are mounted inside a gas-impermeable casing (1). Moreover, means are provided to circulate at least one fluid to he heated inside the tubes, the casing (1) being equipped with a gas exhaust sleeve (122). In this way, a first hot gas, known as the main gas, which is, for example, generated by a burner (6), passes radially through the voids in the bundles. A deflector system (7) ensures that said main hot gas first passes through the primary exchanger (2a) from inside outwards and, subsequently, the secondary exchanger (2b) from outside inwards, after which it is discharged from the exchanger through the above-mentioned sleeve (122). The deflector (7) comprises two adjoining parallel plates (7a, 7b) which are made from a thermally-insulating material. In this way, a second (additional) hot gas can be introduced between the aforementioned plates in order to heat the fluid circulating in the secondary exchanger or to contribute to the heating thereof. The inventive condensation exchanger is suitable, for example, for domestic use.
