Profile of piping for a heat exchanger, heat exchanger for condensation boilers providing said profile, and condensation boiler providing said heat exchanger

1. A profile of piping, in particular piping for making a heat exchanger for a condensation boiler, wherein the profile has a substantially “P” shaped cross-section, the “P” shaped cross-section of the profile has

a trapezoidal portion, having two bases and two sides, and

a triangular portion, having a base and two sides,

wherein a first side of the trapezoidal portion coincides with the base of the triangular portion, wherein a second side and the bases of the trapezoidal portion and the sides of the triangular portion form the inner walls of the profile, wherein a first angle (α) between a first base of the trapezoidal portion and a first side of the triangular portion adjacent to it is between 45° and 135°, wherein a second angle (β) between a second base of the trapezoidal portion and a second side of the triangular portion adjacent is 225°.

2. The profile according to claim 1 , wherein a third angle (γ) between the first base and the second side of the trapezoidal portion is between 120° and 170°.

3. The profile according to claim 1 , wherein contact points for the angles (α,β, γ) between adjacent walls are rounded.

4. A coiled heat exchanger comprising the profile of claim 1 arranged in spiral so as to comprise a plurality of coils winded up one on the other in respect to a central axis (y), wherein the first base of the trapezoidal portion of the profile of each coil is tilted with respect to said central axis (y) of a fourth angle (δ) between 10° and 60°.

5. The coiled heat exchanger according to claim 4 , wherein said coils are arranged in such way as to have the second base of the trapezoidal portion of the cross-section of the profile of a first coil parallel to the first base of the trapezoidal portion of the cross-section of the profile of a coil adjacent and separated of a distance (d x ) between 0.5 mm and 2 mm.

6. A condensation boiler comprising a coiled heat exchanger according to claim 4 .

7. The condensation boiler according to claim 6 , comprising a combustion zone, a condensation zone, and a dividing wall between said two zones, wherein, in said condensation zone, said coils are distanced from said dividing wall of one distance (d z ) between 0.1 mm and 20 mm.

8. The condensation boiler according to claim 6 , comprising an external casing, and wherein each of said coils is distanced from said external casing of one distance (d y ) between 0.1 mm and 20 mm.

9. The condensation boiler according to claim 8 , comprising a slotted casing between said external casing and said coiled heat exchanger in correspondence of said combustion zone and/or of said condensation zone.

10. The condensation boiler according to claim 7 , wherein the height of said combustion zone is between 30% and 65% of the height of the boiler.

11. The condensation boiler according to claim 7 , being oriented in such way that the central axis (y) of the coiled heat exchanger is arranged vertically or tilted of an inclination between 4° and 90°.

12. The profile of piping according to claim 1 , wherein the first angle (α) is 90°.

13. The coiled heat exchanger according to claim 4 , wherein the fourth angle (δ) is 45°.