FR2554565A1 - CONDENSING BOILER - Google Patents

Abstract

CONDENSATION BOILER OF THE TYPE INCLUDING A MAIN EXCHANGER AND AN AUXILIARY EXCHANGER, CALLED CONDENSATION EXCHANGER, ENSURING THE RECOVERY OF THE CALORIES CONTAINED IN THE FUMES, CHARACTERIZED IN THAT THE AUXILIARY EXCHANGER 28 IS PLACED VERTICALLY SHIELDED 26 IN A STAINLESS STEEL 26, PREFERENCE, ARRANGED IN THE REAR PART 22 OF THE BOILER, BETWEEN THE FUMES EXIT 18 FROM THE BOILER AND THE EXHAUST OF THESE FUMES TOWARDS THE ATMOSPHERE.

Description

1, The present invention relates to a so-called condensation boiler,

  that is to say a boiler comprising a condenser allowing the recovery

  tion of the calories contained in the fumes, at the outlet of the boiler, and which

  are generally discharged into the exhaust gas exhaust system.

  It is known that a conventional boiler, in particular a gas-heated boiler, evacuates combustion products at relatively high temperature, which contain a large amount of water vapor. We therefore thought of cooling these combustion products to condense the water vapor they contain, and recover the latent heat of vaporization. For this purpose, we have been led to use an auxiliary exchanger which is placed on the smoke path, to recover most of the calories and transfer them to the heating circuit. Various types of condensing boilers are known which include a main exchanger and an auxiliary exchanger mounted on the flue gas path, after their passage through the main exchanger. In these known boilers, the auxiliary exchanger is generally placed above the main exchanger, preferably in the fume boot of the boiler, and it is inclined horizontally, in order to facilitate evacuation and collection. of

condensation water.

  These boilers are generally satisfactory, but they have

  however the disadvantage of being expensive to build and of laying

  difficult problems to solve, especially with regard to their maintenance,

  due to the position of the auxiliary exchanger.

  The present invention proposes to overcome the drawbacks of heating

  known condensation ders, while making it possible to easily and economically produce a condensation boiler from a conventional type boiler. To this end, the invention relates to a condensing boiler of the type

  comprising a main exchanger and an auxiliary exchanger ensuring recovery

  ration of calories contained in the fumes, characterized in that said

  auxiliary exchanger is placed vertically in a sealed channel, preferably

  U-shaped stainless steel pipe arranged in the rear part of the boiler, between the outlet of the fumes from the boiler and the evacuation of these fumes to the atmosphere, this channel comprising, at its lower part, a

  conduit for condensate drainage.

  According to the invention, the auxiliary exchanger is a finned block, these latter

  nières being arranged vertically and traversed by the heating starting water tube, going towards the main exchanger. Preferably, the end

  bottom of each fin is in the shape of a point, in order to promote the flow

  condensation water and clear the passage between the fins to

combustion products.

  According to the invention, the sealed channel comprises a hermetic cover

  removable, ensuring access from above to the auxiliary exchanger.

  The invention can be applied either to a vacuum boiler or to

  a boiler with classic evacuation by chimney.

  Other characteristics and advantages of the present invention resur-

  will derive from the description given below with reference to the appended drawings, which

  illustrate two exemplary embodiments thereof, devoid of any limiting character

  tif. In the drawings: - Figure 1 is a schematic profile view, in vertical section, of a first embodiment of a boiler according to the invention, of the forced extraction type;

  - Figure 2 is a schematic view, similar to Figure 1, illus-

  trant a second embodiment of a boiler according to the invention, of the chimney evacuation type; and,

  - Figure 3 is a front view of the auxiliary heat exchanger of the boiler

according to the invention.

  Referring to the drawings, it can be seen that a boiler 10 according to the invention

  tion comprises, as known, a burner 12, an exchanger 14, placed immediately

  diat above the burner, on the combustion gas path, an ex-

  tractor 16, and a smoke evacuation duct 18. In the embodiment illustrated in FIG. 1, the invention applies to a boiler with

  suction cup 20, while the second exemplary embodiment, illustrated by Fig.

  gure 2, applies to a chimney exhaust boiler.

  In both cases, a second exchanger is provided to ensure the re-

  recovery of the calories contained in the fumes (this exchanger is generally-

  ment called "condensation generator"), which is positioned in the rear part 22 of the boiler containing the expansion vessel 24. This exchanger

  condensing aid 28 is positioned in a sealed channel 26, pre-

  U-shaped ference and stainless steel, which is placed between the exhaust fumes to the outside, 20 or 20 ', and the outlet 18 of the extractor 16. This exchanger 28, arranged vertically in the sealed channel 26 , is a block with vertica] s fins and it is crossed by the water tube 30 for heating return, going towards the main exchanger 14. At the inlet 32 of the fin block of this auxiliary exchanger 28, this tube 32 is connected to the return of the heating installation (central heating radiators), the forced circulation of this water being carried out by means of an accelerator 34. At its lower part, the sealed channel 26 is provided with a discharge tube condensate 36, closed by a float (not shown in the drawing). According to a characteristic of the invention, the lower end of each fin preferably has the shape of a point, in order to promote the flow of the condensation water and to release the

  passage between the fins for combustion products.

  In the embodiment illustrated in FIG. 1, it can be seen that fresh air is admitted into the boiler via the conduit 38, the burnt gases passing through the main exchanger 14 and being pushed back by the extractor 16 to the through line 18, to pass through the auxiliary exchanger 28, before being evacuated to the outside by the suction cup 20. The burnt gases first transmit their calories to the exchanger 14, by heating the water admitted into this exchanger via line 33, the burnt gases then arrive on exchanger 28, at a temperature which is still fairly high, and they transmit their last

  calories, by condensation, to the water circulating in this auxiliary exchanger 28.

  The water arrives in this auxiliary exchanger 28 from the heating return.

  fage, and it goes to the main exchanger 14 via the

  lines 30, 33, and the heated water is directed to the heaters

  central fage by line 31. This gives maximum efficiency, the

  fumes discharged to the outside being at very low temperature.

  The condensed water produced in the auxiliary exchanger 28 is re-

  collected at the bottom of the watertight channel 26, then it is discharged through the tube 36.

  As stated above, a float is provided to prevent any outflow.

  tie of the combustion gases through the pipe 36, when there is no

  condensation, this float acting as a non-return valve.

  According to the invention, the sealed channel 26 is provided with an opening at its upper part which is hermetically sealed by a cover 39 (FIG. 3). It is thus very easy to disassemble the exchanger

  auxiliary 28, if necessary.

  In the variant illustrated in Figure 2, the invention is applied to a chimney exhaust boiler 20 '. In this boiler, the fresh air intake takes place directly in the room where the boiler is placed, this

  the latter being also identical to the boiler described above with reference to

  Refer to Figure 1. It is understood that the main advantage of the invention is to allow to easily produce a condensing boiler starting from a conventional boiler. It remains to be understood that the present invention is not limited to the various embodiments described and shown here, but that it

includes all variants.

Claims (7)

  1 - Condensing boiler of the type comprising a main exchanger   and an auxiliary exchanger, called condensation exchanger, ensuring the recovery   ration of calories contained in the fumes, characterized in that said auxiliary exchanger (28) is placed vertically in a sealed channel (26), preferably of stainless steel, disposed in the rear part (22) of the boiler, between the outlet of the fumes (18) from the boiler and the evacuation of these fumes to the atmosphere.   2 - Condensing boiler according to claim 1, characterized in that said sealed channel (26) is U-shaped.   3 - Condensing boiler according to one of claims 1 or Z,   characterized in that said sealed channel (26) is provided with an evacuation duct   cuation of condensates (36), placed at its lower part.   4 - Condensing boiler according to claim 3, characterized in   that the condensate drain pipe is provided with a float for   ter any exit of combustion gases through this conduit, when there is no condensation.   - Condensing boiler according to any one of the claims   above, characterized in that said auxiliary exchanger (28) is of the type   fin block, the fins of which are arranged vertically.   6 - Condensing boiler according to claim 5, characterized in that the lower end of each fin of the auxiliary exchanger is in the shape of a point, in order to promote the flow of the condensation water and   clear the passage between the fins for combustion products.   7 - Condensing boiler according to any one of claims   previous, characterized in that the auxiliary exchanger (28) is traversed by   the heating return water, the water heated in this auxiliary exchanger   then the main exchanger before being directed into the heating installation.   8 - Condensing boiler according to any one of claims   above, characterized in that said sealed channel (26) comprises a neck   hermetic ring (39) to facilitate access to said auxiliary exchanger (28).