Heat exchanger and water heater

Abstract

To provide an upper exhaust-type heat exchanger which can favorably secure seal performance.SOLUTION: An upper exhaust-type heat exchanger comprises; a bottomed box-shaped housing 22 in which a heat transmission pipe 21 is arranged, and whose upper end is opened; a housing main body part 23 having a gas inlet 28 at a rear wall part, and a fixed part 27 having a flange part 27A at an upper-end peripheral edge part and a caulking part 27B extending to an outer edge part of the flange part; a lid body 24 which has a gas outlet 41 upwardly opened at a ceiling face, and blocks the housing main body part by being caulked by the caulking part with the external peripheral edge part overlapping an upper side of the flange part; and a partitioning part 25 fixed to the lid body and partitioning an internal space S1 formed of the lid body and the housing main body part into an arrangement region S2 in which the heat transmission pipe is arranged and an upper-side region S3 communicating with the gas outlet at a side closer to the lid body than the arrangement region. The partitioning part comprises: a bottom plate 43 arranged at a lower side of the lid body with an interval; and an extension part 44 extending to the lid body side from left-and-right both edge parts of the bottom plate and a rear edge part. Front edge parts of the lid body and the partitioning part constitute an opening 46 which connects the arrangement region and the upper-side region, and at least a part of the extension part is fixed in a form in contact with a lower face of the lid body.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a heat exchanger and a water heater.

Background Art

[0002] Conventionally, as a water heater that discharges combustion exhaust gas upward after heat exchange in a secondary heat exchanger, a water heating device described in Japanese Patent Application Laid-Open No. 2018-31496 (Patent Document 1 below) is known. The secondary heat exchanger described in Patent Document 1 includes a plurality of heat transfer tubes and a case in which the plurality of heat transfer tubes are disposed inside. An inclined wall portion that slopes downward toward the front is provided on the upper wall portion of the case, and an opening portion is provided in a region between the front portion of the upper wall portion and the front end portion of the inclined wall portion. A flat box-shaped exhaust top that covers the inclined wall portion and the opening portion from above is fixed to the upper wall portion of the secondary heat exchanger, and an exhaust port that protrudes upward is provided in the exhaust top. The combustion exhaust gas introduced into the case flows forward in the region below the inclined wall portion, and after the amount of heat of the combustion exhaust gas is recovered by the heat transfer tubes, it rises along the front wall portion of the case and flows into the space between the inclined wall portion of the case and the exhaust top through the opening portion. Thereafter, the combustion exhaust gas flows backward along the inclined wall portion and is discharged to the outside through the exhaust port.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Regarding the fixing of the exhaust top to the above secondary heat exchanger, fixing methods such as spot welding and screwing are adopted, but such fixing methods do not have very good productivity. Further, according to such a fixing method, the sealing property is likely to be poor at the portion where the upper wall portion of the secondary heat exchanger and the exhaust top are fixed.

[0005] The present disclosure has been completed based on the above circumstances, and an object thereof is to provide an upward exhaust type heat exchanger that is excellent in productivity and can ensure good sealing performance.

Means for Solving the Problems

[0006] The heat exchanger of the present disclosure is a heat exchanger that discharges combustion exhaust gas from above, and includes a plurality of heat transfer tubes and a housing in which the plurality of heat transfer tubes are disposed. The housing has a bottomed box shape with an open upper portion, a gas inlet is formed in the rear wall portion, and a fixed portion having a flange portion that extends in a flange shape from the peripheral edge portion of the upper end portion and a caulking portion that extends to the outer edge portion of the flange portion. A lid body having a gas outlet that opens upward on the top surface, and the outer peripheral edge portion is caulked by the caulking portion of the fixed portion in a state of overlapping the upper side of the flange portion of the fixed portion to close the housing body portion, and is fixed to the lid body, and the plurality of heat transfer tubes are arranged in an internal space formed by the lid body and the housing body portion. A partition portion that partitions the upper region that is disposed on the lid body side relative to the arrangement region and communicates with the gas outlet, the partition portion includes a bottom plate that is disposed at a distance below the lid body, and an extension portion that extends from the left and right edge portions and the rear edge portion of the bottom plate toward the lid body side, and the front edge portion of the lid body and the partition portion form an opening that connects the arrangement region and the upper region, and at least a part of the extension portion is fixed in a manner of contacting the lower surface of the lid body.

[0007] Alternatively, the heat exchanger of the present disclosure is a heat exchanger that discharges combustion exhaust gas from above, and includes a plurality of heat transfer tubes and a housing in which the plurality of heat transfer tubes are disposed. The housing has a bottomed box shape with an open upper portion, a gas inlet is formed in the rear wall portion, and a fixed portion having a flange portion that extends in a flange shape from the peripheral edge portion of the upper end portion and a caulking portion that extends to the outer edge portion of the flange portion. A housing main body portion, a gas outlet that opens upward is provided on the top surface, and a lid body that closes the housing main body portion by being caulked by the caulking portion of the fixed portion with the outer peripheral edge portion overlapping the upper side of the flange portion of the fixed portion. A partition portion that partitions the internal space formed by the lid body and the housing main body portion into a disposition region where the plurality of heat transfer tubes are disposed and an upper region that is disposed on the lid body side with respect to the disposition region and communicates with the gas outlet. The partition portion includes a bottom plate that is disposed at a distance below the lid body, and extending portions that extend from the left and right edge portions and the rear edge portion of the bottom plate toward the lid body side. The front edge portion of the lid body and the partition portion constitute an opening that connects the disposition region and the upper region, and at least a part of the extending portion is sandwiched between the flange portion and the outer peripheral edge portion of the lid body. The outer peripheral edge portion of the lid body is sandwiched between the flange portion and the outer peripheral edge portion of the lid body by being caulked by the caulking portion.

[0008] The water heater of the present disclosure includes a burner device that generates combustion exhaust gas and any one of the above heat exchangers.

Advantages of the Invention

[0009] According to the present disclosure, it is possible to provide an upward exhaust type heat exchanger that is excellent in productivity and can ensure good sealing performance.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Mode for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present disclosure will be listed and exemplified. (1) The heat exchanger of the present disclosure is a heat exchanger that discharges combustion exhaust gas from above, and includes a plurality of heat transfer tubes and a housing in which the plurality of heat transfer tubes are disposed. The housing has a bottomed box shape with an open upper portion, a gas inlet is formed in the rear wall portion, and a fixed portion having a flange portion that extends in a flange shape from the peripheral edge portion of the upper end portion and a caulking portion that extends to the outer edge portion of the flange portion. A housing main body portion, a gas outlet that opens upward is provided on the top surface, and a lid body that closes the housing main body portion by being caulked by the caulking portion of the fixed portion with the outer peripheral edge portion overlapping the upper side of the flange portion of the fixed portion. A partition portion that is fixed to the lid body and partitions the internal space formed by the lid body and the housing main body portion into a disposition region where the plurality of heat transfer tubes are disposed and an upper region that is disposed on the lid body side with respect to the disposition region and communicates with the gas outlet. The partition portion includes a bottom plate that is disposed at a distance below the lid body, and extending portions that extend from the left and right edge portions and the rear edge portion of the bottom plate toward the lid body side. The front edge portion of the lid body and the partition portion constitute an opening that connects the disposition region and the upper region, and at least a part of the extending portion is fixed in a manner that contacts the lower surface of the lid body. The heat exchanger is as described above.

[0012] According to such a configuration, the portion for fixing the partition portion and the lid body is disposed on the internal space side, and the housing main body portion and the lid body are caulked with each other. Therefore, spot welding or the like does not need to be strictly performed when fixing the partition portion and the lid body, and the productivity of the heat exchanger is improved. Further, since the partition portion is fixed on the internal space side of the housing main body portion and the lid body, it is possible to prevent the combustion exhaust gas from leaking from the portion where the partition portion and the lid body are fixed. By caulking the outer peripheral edge portion of the lid body to which the partition portion is fixed with the caulking portion, the housing main body portion and the lid body can be assembled, and leakage of the combustion exhaust gas from inside the housing can be suppressed.

[0013] Furthermore, since the housing main body of the heat exchanger is in the shape of a bottomed box with an open top, it can be used not only for the production of an upward exhaust type heat exchanger but also for the production of a front exhaust type heat exchanger. Specifically, a gas outlet is provided in the front wall portion of the housing main body to form a box portion, and the box portion can be closed from above by a closing plate having no through holes, thereby constituting the housing of the front exhaust type heat exchanger. Therefore, parts can be shared between the upward exhaust type heat exchanger and the front exhaust type heat exchanger.

[0014] (2) Alternatively, the heat exchanger of the present disclosure is a heat exchanger that discharges combustion exhaust gas from above, and includes a plurality of heat transfer tubes and a housing in which the plurality of heat transfer tubes are disposed inside. The housing has a bottomed box shape with an open top, a gas inlet is formed in the rear wall portion, and a fixed portion having a flange portion that extends in a flange shape from the peripheral edge portion of the upper end portion and a caulking portion that extends to the outer edge portion of the flange portion. A housing main body portion, a gas outlet that opens upward is provided on the top surface, and an outer peripheral edge portion overlaps with the upper side of the flange portion of the fixed portion and is caulked by the caulking portion of the fixed portion to close the housing main body portion. A lid body, a partition portion that partitions the internal space formed by the lid body and the housing main body portion into a disposition region where the plurality of heat transfer tubes are disposed and an upper region that is disposed closer to the lid body side than the disposition region and communicates with the gas outlet. The partition portion includes a bottom plate that is disposed at a distance below the lid body, and extending portions that extend from the left and right edge portions and the rear edge portion of the bottom plate toward the lid body side. The front edge portion of the lid body and the partition portion constitutes an opening that connects the disposition region and the upper region, and at least a part of the extending portion is sandwiched between the flange portion and the outer peripheral edge portion of the lid body, and the outer peripheral edge portion of the lid body is caulked by the caulking portion to be sandwiched between the flange portion and the outer peripheral edge portion of the lid body. It is a heat exchanger.

[0015] According to such a configuration, since the lid body and the partition portion are caulked and fixed to the housing main body portion, screw fastening and spot welding are not required in the manufacturing process of the heat exchanger, and the productivity of the heat exchanger is improved. In addition, the sealing performance of the heat exchanger can be ensured well. Furthermore, since the housing main body of the heat exchanger is in the shape of a bottomed box with an open top, it can be used not only for the upward exhaust type heat exchanger but also for the production of the front exhaust type heat exchanger. Specifically, a gas outlet is provided in the front wall portion of the housing main body to form a box portion, and the box portion can be closed from above by a closing plate having no through holes, thereby constituting the housing of the front exhaust type heat exchanger. Therefore, parts can be made common between the upward exhaust type heat exchanger and the front exhaust type heat exchanger.

[0016] (3) It is preferable that the partition portion extends from the front edge portion of the bottom plate toward the lid body and includes a fixing piece fixed to the lower surface of the lid body.

[0017] According to such a configuration, the partition portion can be stably fixed to the lid body.

[0018] (4) The water heater of the present disclosure is a water heater including a burner device that generates combustion exhaust gas and any one of the above heat exchangers.

[0019] According to such a configuration, it is possible to provide a water heater including a heat exchanger that is excellent in productivity and can ensure good sealing performance.

[0020] <Embodiment 1> Hereinafter, Embodiment 1 will be described with reference to FIGS. 1 to 15. Note that, for a plurality of identical members, only some members may be given reference numerals, and the reference numerals of other members may be omitted.

[0021] [Overall Structure of the Water Heater] FIG. 1 is a front view of the water heater 1 as seen from the front, showing the state with the front cover removed. FIGS. 2 and 3 are views showing the inner cylinder 3 which is a main component arranged inside the outer casing 2 of the water heater 1. As shown in FIGS. 1 to 3, the water heater 1 includes a burner device 4, a primary heat exchanger 10, a secondary heat exchanger 20 (an example of a heat exchanger), a path member 50, a water inlet pipe 13, a hot water outlet pipe 14, a relay pipe 15, etc., and has a function of heating the tap water supplied from the outside and discharging hot water. The burner device 4 burns combustion gas to generate combustion exhaust gas. The combustion exhaust gas generated by the burner device 4 passes through the primary heat exchanger 10, then through the path member 50, and is sent to the secondary heat exchanger 20 and discharged to the outside of the water heater 1. In the primary heat exchanger 10, the sensible heat of the combustion exhaust gas is recovered, and in the secondary heat exchanger 20, the latent heat of the combustion exhaust gas is recovered.

[0022] The water inlet pipe 13 is configured as a path through which water is supplied, and as shown in FIG. 3, it is connected to the first header 37 of the secondary heat exchanger 20. As shown in FIGS. 8 and 9, the first header 37 is connected to a plurality of heat transfer pipes 21 housed in the housing 22. The ends of the plurality of heat transfer pipes 21 on the side opposite to the first header 37 are connected to the second header 38. As shown in FIG. 3, the second header 38 is connected to the primary heat transfer pipe 12 arranged inside the primary heat exchanger 10 via the relay pipe 15. As shown in FIGS. 1 and 2, the end of the primary heat transfer pipe 12 of the primary heat exchanger 10 on the side opposite to the relay pipe 15 is connected to the hot water outlet pipe 14. The hot water outlet pipe 14 is configured as a path for sending out hot water. That is, in the water heater 1, the water flowing in from the water inlet pipe 13 flows through the plurality of heat transfer pipes 21 of the secondary heat exchanger 20, the relay pipe 15, and the primary heat transfer pipe 12 of the primary heat exchanger 10 in this order. Then, the water flowing through the inside of the plurality of heat transfer pipes 21 of the secondary heat exchanger 20 and the primary heat transfer pipe 12 of the primary heat exchanger 10 receives the heat quantity of the combustion exhaust gas and is heated, and flows out as hot water from the hot water outlet pipe 14.

[0023] As shown in Fig. 1, the water heater 1 is provided with a drain hose 5. The upstream side of the drain hose 5 is connected to a drain outlet 26 (see Fig. 2) of the secondary heat exchanger 20 described later, and the downstream side is connected to a neutralizer. The drain generated by recovering the latent heat of the combustion exhaust gas in the secondary heat exchanger 20 is discharged to the outside of the secondary heat exchanger 20 through the drain outlet 26 and sent to the neutralizer through the drain hose 5.

[0024] As shown in Fig. 1, the water heater 1 includes a controller 6 as a control device. The controller 6 is configured as, for example, a known microcomputer or the like, and is configured to be able to acquire signals from various sensors provided in the water heater 1 and control various actuators provided in the water heater 1. For example, when the water heater 1 detects the flow of water in the water inlet pipe 13 by a water flow sensor (not shown), it operates the burner device 4 to generate hot water.

[0025] As shown in Figs. 2 and 3, the primary heat exchanger 10 includes a can body 11 and primary heat transfer pipes 12. The can body 11 has a substantially rectangular shape in plan view that is long in the left-right direction and is formed in a cylindrical shape that penetrates vertically. The primary heat transfer pipes 12 of the primary heat exchanger 10 are arranged inside the can body 11 and include a plurality of straight pipes extending in the front-rear direction and connection pipes that connect the front ends or rear ends of two straight pipes adjacent to each other in the left-right direction outside the can body 11. The plurality of straight pipes are connected in series through the connection pipes. That is, the primary heat transfer pipes 12 of the primary heat exchanger 10 are formed in a meandering shape as a whole. The can body 11 and the primary heat transfer pipes 12 can be made of copper with excellent thermal conductivity.

[0026] The primary heat exchanger 10 is fixed to the upper end portion of the burner device 4 and is arranged such that the combustion exhaust gas generated by the burner device 4 passes through the inside of the can body 11 of the primary heat exchanger 10 from below to above. Further, a path member 50 described later is fixed to the upper end portion of the primary heat exchanger 10, and the combustion exhaust gas whose sensible heat has been recovered by the primary heat exchanger 10 is sent to the path member 50.

[0027] As shown in FIG. 3, a relay pipe 15 is connected to the opening at the rear and right end of the primary heat transfer pipe 12 so that water from the secondary heat exchanger 20 flows in. As shown in FIG. 2, a hot water outlet pipe 14 is connected to the opening at the front and left side of the primary heat transfer pipe 12 so that the heated water flows out. That is, in the primary heat exchanger 10, the water flowing in from the rear surface side on the right side of the can body 11 through the relay pipe 15 meanders inside the primary heat transfer pipe 12 and exchanges heat with the combustion exhaust gas passing through the can body 11 and is heated. Then, the heated hot water flows into the hot water outlet pipe 14 from the front surface side on the left side of the can body 11.

[0028] [Secondary heat exchanger] Next, the configuration of the secondary heat exchanger 20 will be described in detail. As shown in FIGS. 1 to 3, the secondary heat exchanger 20 is disposed above the primary heat exchanger 10. The secondary heat exchanger 20 and the primary heat exchanger 10 are connected by a path member 50 for introducing the combustion exhaust gas that has passed through the primary heat exchanger 10 into the secondary heat exchanger 20.

[0029] As shown in FIG. 5, the secondary heat exchanger 20 includes a plurality (seven in this embodiment) of heat transfer pipes 21 and a housing 22 in which the plurality of heat transfer pipes 21 are arranged inside. The plurality of heat transfer pipes 21 and the housing 22 can be made of stainless steel with excellent corrosion resistance.

[0030] [Housing, housing main body part] As shown in FIG. 11, the housing 22 includes a bottomed box-shaped housing main body part 23 with an open top, a lid body 24 that closes the housing main body part 23 from above, and a partition part 25 arranged inside the housing 22. As shown in Fig. 14, the housing main body 23 includes a bottom wall portion 23A, a front wall portion 23B rising from the front edge of the bottom wall portion 23A, a rear wall portion 23C rising from the rear edge of the bottom wall portion 23A, a right wall portion 23D rising from the right edge of the bottom wall portion 23A, and a left wall portion 23E rising from the left edge of the bottom wall portion 23A. The front wall portion 23B, the right wall portion 23D, the rear wall portion 23C, and the left wall portion 23E constitute the peripheral wall portion of the housing main body 23. A drain outlet 26 penetrating the bottom wall portion 23A in the vertical direction is provided in the front side portion of the bottom wall portion 23A. As shown in Fig. 5, in the water heater 1, the bottom wall portion 23A is arranged to incline downward as it goes forward, facilitating the discharge of the drain generated along with the latent heat recovery in the secondary heat exchanger 20 to the drain outlet 26.

[0031] [Fixing portion, flange portion, clamping portion] As shown in Fig. 11, a fixing portion 27 for clamping and fixing the lid body 24 to the housing main body 23 is provided at the upper end portion of the peripheral wall portion of the housing main body 23. As shown in Fig. 14, the fixing portion 27 has a flange portion 27A that extends outward in a flange shape from the upper end peripheral edge portion of the peripheral wall portion, and a clamping portion 27B that extends upward from the outer edge portion of the flange portion 27A. As shown in Fig. 6, the clamping portion 27B is a portion that deforms when the lid body 24 is clamped to the housing main body 23. In the state where the lid body 24 is clamped to the housing main body 23, the clamping portion 27B deforms so as to sandwich the fixed portion 24A provided at the outer peripheral edge portion of the lid body 24 together with the flange portion 27A in the vertical direction. Further, an annular packing 27C is interposed between the fixed portion 24A and the clamping portion 27B, preventing the passage of gas between the lid body 24 and the housing main body 23.

[0032] [Gas inlet] As shown in FIG. 14, a gas inlet 28 penetrating in the front-rear direction is formed in the rear wall portion 23C of the housing main body portion 23. The gas inlet 28 is an opening for introducing combustion exhaust gas into the interior of the housing 22. A plurality of connected portions 29 are formed at the peripheral edge of the gas inlet 28 in the rear wall portion 23C. The connected portion 29 has a female screw shape and is configured to attach the path member 50 as shown in FIGS. 6 and 7. That is, combustion exhaust gas is introduced into the interior of the housing 22 from the path member 50 through the gas inlet 28.

[0033] As shown in FIG. 8, a right-side opening 33 penetrating in the left-right direction is formed in the right wall portion 23D of the housing main body portion 23. The right-side opening 33 is an opening for accommodating a plurality of heat transfer tubes 21 assembled to an assembly 35 described later. A plurality of connected portions 34 are formed around the right-side opening 33 in the right wall portion 23D. The connected portion 34 has a female screw shape and is used for attaching the assembly 35.

[0034] [a plurality of heat transfer tubes] As shown in FIG. 8, the assembly 35 includes a plurality of heat transfer tubes 21, a plate-shaped closing member 36, a first header 37, and a second header 38. As shown in FIG. 10, the heat transfer tube 21 extends in a meandering manner along a predetermined planar direction. Each of the heat transfer tubes 21 has a common shape. The heat transfer tube 21 has a plurality (six in this embodiment) of straight tube portions 21A, at least one (five in this embodiment) of U-shaped tube portions 21B, a first connection portion 21C, and a second connection portion 21D.

[0035] Each of the plurality of straight pipe portions 21A is arranged in parallel in a direction (front-rear direction) orthogonal to the direction (left-right direction) in which the plurality of straight pipe portions 21A extend. The end portions of two adjacent straight pipe portions 21A in the front-rear direction are connected by a U-shaped pipe portion 21B that bends in a U shape. However, the right end portions of the straight pipe portion 21A arranged in the frontmost row and the straight pipe portion 21A arranged in the rearmost row are not connected to the U-shaped pipe portion 21B and are open to the right. The right end portion of the straight pipe portion 21A in the frontmost row is a first connection portion 21C, and the right end portion of the straight pipe portion 21A in the rearmost row is a second connection portion 21D. The plurality of straight pipe portions 21A and the U-shaped pipe portions 21B are alternately connected from the first connection portion 21C to the second connection portion 21D, so that the heat transfer pipes 21 are connected in series.

[0036] As shown in FIG. 8, the plurality of heat transfer pipes 21 are fixed to the closing member 36 in a state of being stacked in the vertical direction and housed in the housing 22. As shown in FIG. 5, in a state where the plurality of heat transfer pipes 21 are arranged inside the housing 22, the plurality of straight pipe portions 21A extend in the left-right direction and are arranged at intervals in the vertical direction and the front-rear direction. More specifically, two heat transfer pipes 21 adjacent in the vertical direction are arranged offset from each other in the front-rear direction, and the plurality of straight pipe portions 21A are arranged in a staggered pattern as a whole in a side sectional view. Among the plurality of heat transfer pipes 21, since the straight pipe portions 21A are arranged orthogonal to the direction in which the combustion exhaust gas flows (mainly in the front-rear direction and the vertical direction), the heat exchange between the water flowing through the plurality of heat transfer pipes 21 and the combustion exhaust gas is mainly performed in the straight pipe portions 21A.

[0037] As shown in Fig. 8, the closing member 36 is a plate-shaped member for closing the right opening 33 from the right in a state where a plurality of heat transfer tubes 21 are housed in the housing 22. As shown in Fig. 9, the closing member 36 has a first through hole through which the first connection portions 21C of the plurality of heat transfer tubes 21 are inserted, a second through hole through which the second connection portions 21D of the plurality of heat transfer tubes 21 are inserted, and an insertion hole through which the connecting member 36A is inserted, which are formed to penetrate in the left-right direction. A burring portion is provided in the first through hole, and the first connection portion 21C is fixed to the closing member 36 by brazing or the like in a state of being inserted into the first through hole. Similarly, the second connection portion 21D is also fixed to the closing member 36 by brazing or the like in a state of being inserted into the second through hole. As shown in Fig. 8, the insertion hole is provided at a position corresponding to the connected portion 34, and the closing member 36 is fixed to the right wall portion 23D by connecting the connecting member 36A inserted into the insertion hole to the connected portion 34. An annular packing 36B is provided between the right wall portion 23D and the closing member 36. Thereby, the passage of gas between the right wall portion 23D and the closing member 36 is prevented.

[0038] As shown in Fig. 3, the first header 37 is a portion connecting the inlet of the secondary heat exchanger 20 (specifically, the opening of the first connection portion 21C of the plurality of heat transfer tubes 21) and the downstream side of the water inlet pipe 13. As shown in Fig. 9, the first header 37 includes a first header main body 37A fixed to the closing member 36, a first header lid 37B covering the opening of the first header main body 37A, and a joint cylinder 37C. The first header main body 37A has a first bottom hole 37D through which the first connection portion 21C inserted into the closing member 36 is inserted. The first header lid 37B has a first lid hole 37E to which the joint cylinder 37C is attached. The joint cylinder 37C is a portion connected to the downstream side of the water inlet pipe 13.

[0039] As shown in FIG. 3, the second header 38 is a portion that connects the outlet of the secondary heat exchanger 20 (specifically, the opening of the second connection portion 21D of the plurality of heat transfer tubes 21) and the pipe on the inlet side of the primary heat exchanger 10 (specifically, the upstream end of the relay pipe 15). As shown in FIG. 9, the second header 38 includes a second header main body 38A fixed to the closing member 36, a second header lid 38B that covers the opening of the second header main body 38A, and a joint cylinder 38C. The second header main body 38A has a second bottom hole 38D through which the second connection portion 21D inserted through the closing member 36 is inserted. The second header lid 38B has a second lid hole 38E to which the joint cylinder 38C is attached. The joint cylinder 38C is a portion connected to the upstream side of the relay pipe 15. As a method for assembling the headers 37 and 38 and fixing the headers 37 and 38 to the closing member 36 and the like, brazing, welding, or the like can be used.

[0040] In the secondary heat exchanger 20, the water supplied from the water inlet pipe 13 is passed in parallel from the first connection portion 21C of each heat transfer tube 21 through the first header 37. The water flow exchanges heat with the combustion exhaust gas flowing in the housing 22 while flowing in a meandering shape through each heat transfer tube 21. The water heated by the heat exchange flows from the second connection portion 21D through the second header 38 into the relay pipe 15.

[0041] [Cover, Gas Outlet] As shown in FIG. 11, the cover 24 is a plate-like member and includes a bulging portion 39 that bulges upward at the central portion and a fixed portion 24A disposed at the outer edge of the bulging portion 39. A gas outlet 41 penetrating in the vertical direction is formed on the top surface of the bulging portion 39. As shown in FIG. 4, the gas outlet 41 is located at the central position in the left-right direction and closer to the front in the housing 22. As shown in FIG. 5, a cylindrical exhaust pipe 42 protruding upward is provided at the peripheral edge of the gas outlet 41. The combustion exhaust gas from which the latent heat has been recovered in the secondary heat exchanger 20 is discharged to the outside through the gas outlet 41. Specifically, the combustion exhaust gas is discharged to the outside through an exhaust pipe portion (not shown) connected to the exhaust pipe 42.

[0042] As shown in FIG. 11, when the lid 24 is clamped and fixed to the housing main body 23, the portion to be fixed 24A is disposed above the flange portion 27A of the housing main body 23 and is clamped by the clamping portion 27B. As shown in FIG. 6, the portion to be fixed 24A is configured to be clamped in the vertical direction by the flange portion 27A and the clamping portion 27B. By clamping and fixing the lid 24 to the housing main body 23, the housing main body 23 is closed.

[0043] [Partition portion] As shown in FIG. 5, the partition portion 25 is a plate-like member fixed to the lower surface of the lid 24, and vertically partitions the internal space S1 formed by the housing main body 23 and the lid 24. Specifically, the partition portion 25 partitions the internal space S1 into a layout region S2 in which a plurality of heat transfer tubes 21 are arranged, and an upper region S3 disposed on the lid 24 side (upper side) of the layout region S2. The upper region S3 communicates with the gas outlet 41 above. The layout region S2 and the upper region S3 communicate with each other through an opening 46 and a plurality of through holes 43A described later.

[0044] [Bottom plate] As shown in FIG. 13, the partition portion 25 includes a bottom plate 43, extending portions 44 extending upward from the left and right edge portions and the rear edge portion of the bottom plate 43, and a fixing piece 45 extending upward from the front edge portion of the bottom plate 43. The bottom plate 43 has a rectangular plate shape. A plurality (22 in this embodiment) of through holes 43A penetrating in the vertical direction are formed in the bottom plate 43. The plurality of through holes 43A are arranged in two rows in the front-rear direction in a substantially one-third region on the front side of the bottom plate 43 and are arranged near the center in the left-right direction. As shown in FIG. 4, in the housing 22, a part of the plurality of through holes 43A is disposed directly below the gas outlet 41. As shown in FIG. 5, the plurality of through holes 43A communicate the layout region S2 and the upper region S3. The bottom plate 43 is disposed at a distance below the lid 24.

[0045] [Extending portion] As shown in Fig. 13, the extending portion 44 includes a lateral extending portion 44A extending from both left and right end portions of the bottom plate 43, and a rear extending portion 44B extending from the rear edge portion of the bottom plate 43. The lateral extending portion 44A rises upward substantially perpendicularly from the bottom plate 43. The rear extending portion 44B includes a portion that rises upward substantially perpendicularly from the bottom plate 43, and a first fixing portion 44C that further extends rearward from the upper end portion of the rising portion.

[0046] [Fixing piece] In the present embodiment, the fixing piece 45 includes a second fixing portion 45A having a long shape in the left - right direction, and three extending portions 45B that extend obliquely downward rearward from the second fixing portion 45A and are connected to the bottom plate 43. The extending portions 45B are arranged at intervals from each other at the left - right central position, the left - end side, and the right - end side of the second fixing portion 45A. Note that, different from the present embodiment, a plurality of fixing pieces may be provided at intervals in the left - right direction on the front edge portion of the bottom plate, and each fixing piece may be configured to include one second fixing portion and one extending portion.

[0047] As shown in Fig. 5, the first fixing portion 44C of the extending portion 44 and the second fixing portion 45A of the fixing piece 45 are fixed so as to be in contact with the lower surface of the lid body 24. Specifically, the first fixing portion 44C and the second fixing portion 45A are fixed to the lower surface of the lid body 24 by welding or the like without forming holes in the lid body 24. Thereby, it is possible to prevent the combustion exhaust gas from leaking to the outside of the housing 22 at the portion where the partition portion 25 and the lid body 24 are fixed.

[0048] As described above, the housing 22 of the secondary heat exchanger 20 of the present embodiment can be manufactured by a process of manufacturing the housing main body portion 23, the lid body 24, and the partition portion 25, a process of fixing the first fixing portion 44C and the second fixing portion 45A of the partition portion 25 to the lid body 24, and a process of closing the housing main body portion 23 with the lid body 24 to which the partition portion 25 is fixed and caulking and fixing the fixed portion 24A of the lid body 24 by the caulking portion 27B of the housing main body portion 23. Therefore, in the manufacturing process of the secondary heat exchanger 20, complicated processes such as screwing and spot welding can be minimized, so that the productivity of the secondary heat exchanger 20 can be improved.

[0049] In addition, the housing main body 23 can be shared not only for the housing 22 of the upward exhaust type secondary heat exchanger 20 according to the present embodiment but also for the housing of the front exhaust type secondary heat exchanger. Specifically, a gas outlet is provided in the front wall portion 23B of the housing main body 23 to manufacture a box portion, and the upper opening of this box portion is closed by a closing plate provided without a through hole, whereby it is possible to configure the housing of the front exhaust type secondary heat exchanger. Therefore, the manufacturing cost of the upward exhaust type secondary heat exchanger 20 and the housing 22 according to the present embodiment may be reduced.

[0050] In a state where the partition portion 25 is fixed to the lid body 24, as shown in FIG. 12, the lid body 24 and the front edge portion of the partition portion 25 constitute an opening 46 that is open in the front-rear direction. The space (upper region S3) between the lid body 24 and the partition portion 25 is open forward by the opening 46. As shown in FIG. 5, the opening 46 connects the upper region S3 and the arrangement region S2. Further, the upper region S3 is closed by a rearward extension portion 44B at the rear. As shown in FIG. 12, the upper region S3 is defined by sideward extension portions 44A on both sides. Therefore, as shown in FIG. 5, the arrangement region S2 and the upper region S3 are connected via a plurality of through holes 43A and the opening 46.

[0051] As shown in FIG. 5, the opening 46 is arranged in front of the plurality of heat transfer tubes 22 in the housing 22. Therefore, the opening 46 allows the combustion exhaust gas that has reached the vicinity of the straight tube portion 21A in the forefront row among the plurality of heat transfer tubes 21 to pass from the arrangement region S2 to the upper region S3. For this reason, heat recovery can also be achieved in the straight tube portion 21A in the forefront row, and the efficiency of heat transfer from the combustion exhaust gas to the water flowing through the plurality of heat transfer tubes 21 can be improved.

[0052] On the one hand, as shown in FIG. 5, a plurality of through holes 43A in the partition portion 25 are arranged behind the opening 46 and above the front portions of the plurality of heat transfer tubes 21 within the housing 22. For this reason, a part of the combustion exhaust gas that has reached the front side of the arrangement region S2 from the gas inlet 28 has its heat quantity recovered by the water flowing through the plurality of heat transfer tubes 21 in the vicinity, and then flows from the arrangement region S2 to the upper region S3 through the plurality of through holes 43A behind the foremost straight tube portion 21A. That is, the exhaust path that flows from the arrangement region S2 to the upper region S3 via the plurality of through holes 43A is shorter in distance than the exhaust path that flows from the arrangement region S2 to the upper region S3 via the opening 46 provided at the front side within the housing 22, and is a so-called shortcut exhaust path. The combustion exhaust gas passing through the shortcut exhaust path is only a very small part of the whole, and most of the combustion exhaust gas passes through the space in front of the arrangement region S2 and flows to the upper region S3 through the opening 46. Still, by providing the plurality of through holes 43A in the partition portion 25, an increase in the exhaust resistance of the combustion exhaust gas can be suppressed, and the combustion performance of the water heater 1 can be ensured.

[0053] As shown in FIG. 5, the path member 50 is arranged between the primary heat exchanger 10 and the secondary heat exchanger 20. The path member 50 communicates the upper end opening of the can body 11 of the primary heat exchanger 10 and the gas inlet 28 of the rear wall portion 23C of the housing 22 of the secondary heat exchanger 20, and constitutes a flow space S4 through which the combustion exhaust gas flows.

[0054] As shown in FIG. 15, the path member 50 is configured to have a path member main body 51 and a path member rear portion 52. The path member main body 51 is formed in a shape that gradually becomes higher from the front end portion toward the rear in the front-rear direction and bulges upward. The rear end of the path member main body 51 is open to the rear, and a plurality of connected portions are provided at the periphery of this opening. The plurality of connected portions are in the form of female threads and are configured to be connected to the connecting member 52A. The rear part 52 of the path member is formed in a square dish shape that bulges rearward. The rear part 52 of the path member has an insertion hole at a position corresponding to the connected part of the path member main body 51, and a connecting member 52A inserted through this insertion hole is connected to the connected part of the path member main body 51. As a result, as shown in FIG. 7, the rear part 52 of the path member is fixed to the path member main body 51 so as to close the rear opening of the path member main body 51. A packing (not shown) is provided between the path member main body 51 and the rear part 52 of the path member to prevent the passage of gas between the path member main body 51 and the rear part 52 of the path member.

[0055] As shown in FIG. 7, the rear part 52 of the path member has an insertion hole at a position corresponding to the connected part 29 of the rear wall part 23C. By connecting a connecting member 52B inserted through this insertion hole to the connected part 29, the rear part 52 of the path member is fixed to the rear wall part 23C. An annular packing 52C is provided between the rear wall part 23C and the rear part 52 of the path member. The packing 52C prevents the leakage of gas between the rear wall part 23C and the rear part 52 of the path member.

[0056] As shown in FIG. 15, an opening 53 that opens forward is provided in the upper part of the rear part 52 of the path member. As shown in FIG. 5, the opening 53 is the terminal end of the flow space S4 of the path member 50, and the flow space S4 extends obliquely upward in front as it approaches the opening 53, that is, as it approaches the terminal end side. When the path member 50 is attached to the housing 22, the opening 53 communicates with the gas inlet 28.

[0057] [Operation and Effect of Embodiment 1] As described above, the secondary heat exchanger 20 of Embodiment 1 is a secondary heat exchanger 20 that discharges combustion exhaust gas from above, and includes a plurality of heat transfer tubes 21 and a housing 22 in which the plurality of heat transfer tubes 21 are disposed. The housing 22 has a bottomed box shape with an open upper portion, a gas inlet 28 is formed in the rear wall portion 23C, and a housing main body portion 23 includes a flange portion 27A that extends in a flange shape from the peripheral edge portion of the upper end portion and a caulking portion 27B that extends to the outer edge portion of the flange portion 27A. A lid body 24 has a gas outlet 41 that opens upward on the top surface, and the outer peripheral edge portion is caulked by the caulking portion 27B of the fixing portion 27 in a state of overlapping the upper side of the flange portion 27A of the fixing portion 27 to close the housing main body portion 23. A partition portion 25 is fixed to the lid body 24 and divides the internal space S1 formed by the lid body 24 and the housing main body portion 23 into a disposition region S2 in which the plurality of heat transfer tubes 21 are disposed and an upper region S3 that is disposed closer to the lid body 24 side than the disposition region S2 and communicates with the gas outlet 41. The partition portion 25 includes a bottom plate 43 that is disposed at a distance below the lid body 24 and an extension portion 44 that extends from the left and right edge portions and the rear edge portion of the bottom plate 43 toward the lid body 24 side. The front edge portion of the lid body 24 and the partition portion 25 constitutes an opening 46 that connects the disposition region S2 and the upper region S3, and at least a part of the extension portion 44 is fixed in a manner of contacting the lower surface of the lid body 24.

[0058] According to such a configuration, the portion for fixing the partition portion 25 and the lid body 24 is disposed on the internal space S1 side, and since the housing main body portion 23 and the lid body 24 are caulked to each other, it is not necessary to strictly perform spot welding or the like when fixing the partition portion 25 and the lid body 24, and the productivity of the secondary heat exchanger 20 is improved. Further, since the partition portion 25 is fixed to the internal space S1 side of the housing main body portion 23 and the lid body 24, it is possible to prevent combustion exhaust gas from leaking from the portion for fixing the partition portion 25 and the lid body 24. By caulking the outer peripheral edge portion of the lid body 24 to which the partition portion 25 is fixed with the caulking portion 27B, the housing main body portion 23 and the lid body 24 can be assembled, and leakage of combustion exhaust gas from inside the housing 22 can be suppressed.

[0059] Furthermore, since the housing main body 23 of the secondary heat exchanger 20 has a bottomed box shape with an open top, it can be used not only for the upward exhaust type secondary heat exchanger 20 but also for manufacturing a front exhaust type secondary heat exchanger. Specifically, a gas outlet is provided in the front wall portion 23B of the housing main body 23 to form a box portion, and the box portion can be closed from above by a closing plate having no through hole, thereby constituting the housing of the front exhaust type secondary heat exchanger. Therefore, parts can be shared between the upward exhaust type secondary heat exchanger 20 and the front exhaust type secondary heat exchanger.

[0060] Also, in Embodiment 1, the partition portion 25 extends from the front edge portion of the bottom plate 43 toward the lid body 24 and includes a fixing piece 45 fixed to the lower surface of the lid body 24.

[0061] According to such a configuration, the partition portion 25 can be stably fixed to the lid body 24.

[0062] The water heater 1 of Embodiment 1 includes a burner device 4 that generates combustion exhaust gas and a secondary heat exchanger 20.

[0063] According to such a configuration, it is possible to provide a water heater 1 including a secondary heat exchanger 20 that is excellent in productivity and can ensure good sealing performance.

[0064] <Embodiment 2> Hereinafter, Embodiment 2 will be described with reference to FIG. 16. FIG. 16 is a partially enlarged side sectional view of the housing 122 of the secondary heat exchanger 120 of the water heater 101 according to Embodiment 2, and corresponds to FIG. 5 of Embodiment 1. For a plurality of identical members, only some members may be labeled, and the labels of other members may be omitted. Also, members similar to those in Embodiment 1 may be labeled with the same labels as in Embodiment 1 and the description may be omitted.

[0065] The housing 122 of the secondary heat exchanger 120 according to Embodiment 2 includes a housing main body portion 23, a lid body 24, and a partition portion 125. Among the extending portions 144 of the partition portion 125, the rear extending portion 144B includes a portion that rises substantially vertically upward from the bottom plate 43 and a first fixing portion 144C that further extends rearward from the upper end portion of the rising portion. The first fixing portion 144C extends further rearward than the first fixing portion 44C of Embodiment 1.

[0066] The first fixing portion 144C of the extending portion 144 is configured to be clamped together when the fixed portion 24A of the lid body 24 is clamped by the clamping portion 27B of the housing main body portion 23. Specifically, the first fixing portion 144C of the partition portion 125 is disposed above the flange portion 27A of the housing main body portion 23, and in a state where the fixed portion 24A of the lid body 24 is disposed above the first fixing portion 144C, the clamping portion 27B is clamped. Therefore, the first fixing portion 144C is fixed in the housing 122 in a state of being sandwiched vertically by the flange portion 27A and the fixed portion 24A. A packing 27C is interposed between the first fixing portion 144C and the flange portion 27A to prevent combustion exhaust gas from leaking from the housing 122 to the outside.

[0067] As described above, in a configuration in which at least a part of the extending portion 144 is clamped by the clamping portion 27B together with the fixed portion 24A, the first fixing portion 144C may or may not be welded to the lower surface of the lid body 24 in advance. That is, a step of fixing the partition portion 125 to the lid body 24 in advance in the manufacturing process of the housing 122 may be partially omitted. Even when the partition portion 125 is not fixed to the lid body 24, the partition portion 125 can be fixed in the housing 122 by co-clamping the separate lid body 24, partition portion 125, and housing main body portion 23.

[0068] [Operation and Effect of Embodiment 2] Thus, the secondary heat exchanger 120 of Embodiment 2 is a secondary heat exchanger 120 that discharges combustion exhaust gas from above, and includes a plurality of heat transfer tubes 21 and a housing 122 in which the plurality of heat transfer tubes 21 are disposed. The housing 122 has a bottomed box shape with an open upper portion, a gas inlet 28 is formed in the rear wall portion 23C, and a housing main body portion 23 includes a flange portion 27A that extends in a flange shape from the peripheral edge portion of the upper end portion, and a caulking portion 27B that extends to the outer edge portion of the flange portion 27A. A lid body 24 has a gas outlet 41 that opens upward on the top surface, and the outer peripheral edge portion is caulked by the caulking portion 27B of the fixing portion 27 in a state of overlapping the upper side of the flange portion 27A of the fixing portion 27 to close the housing main body portion 23. A partition portion 125 that partitions the internal space S1 formed by the lid body 24 and the housing main body portion 23 into a disposition region S2 where the plurality of heat transfer tubes 21 are disposed and an upper region S3 that is disposed on the lid body 24 side with respect to the disposition region S2 and communicates with the gas outlet 41 is provided. The partition portion 125 includes a bottom plate 43 that is disposed at a distance below the lid body 24, and extending portions 144 that extend from the left and right edge portions and the rear edge portion of the bottom plate 43 toward the lid body 24 side. The front edge portion of the lid body 24 and the partition portion 125 constitutes an opening 46 that connects the disposition region S2 and the upper region S3. At least a part of the extending portion 144 is sandwiched between the flange portion 27A and the outer peripheral edge portion of the lid body 24, and the outer peripheral edge portion of the lid body 24 is sandwiched by the flange portion 27A and the outer peripheral edge portion of the lid body 24 when the outer peripheral edge portion of the lid body 24 is caulked by the caulking portion 27B.

[0069] According to such a configuration, since the lid body 24 and the partition portion 125 are caulked and fixed to the housing main body portion 23, screw fastening and spot welding are not required in the manufacturing process of the secondary heat exchanger 120, and the productivity of the secondary heat exchanger 120 is improved. Further, the sealing performance of the secondary heat exchanger 120 can be ensured satisfactorily. Furthermore, since the housing main body 23 of the above-described secondary heat exchanger 120 has a bottomed box shape with an open top, it can be used not only for the upward exhaust type secondary heat exchanger 120 but also for the manufacture of the front exhaust type secondary heat exchanger. Specifically, a gas outlet is provided in the front wall portion 23B of the housing main body 23 to form a box portion, and the box portion can be closed from above by a closing plate having no through hole, thereby constituting the housing of the front exhaust type secondary heat exchanger. Therefore, parts can be made common between the upward exhaust type secondary heat exchanger 120 and the front exhaust type secondary heat exchanger.

[0070] <Other Embodiments> The present disclosure is not limited to the embodiments described above with reference to the description and drawings. For example, the features of the above-described or below-described embodiments can be combined in any combination without contradiction. Also, any feature of the above-described or below-described embodiments can be omitted unless explicitly specified as essential. Furthermore, the above-described embodiments may be modified as follows.

[0071] In the above embodiment, the secondary heat exchangers 20 and 120 are exemplified as an example of the heat exchanger, but the heat exchanger may be a primary heat exchanger.

[0072] In Embodiment 1, the partition portion 25 includes three fixing pieces 45, but the number of fixing pieces is not limited to three, and a configuration without fixing pieces may also be used.

[0073] In Embodiment 1, the first fixing portion 44C of the rearward extending portion 44B of the extending portion 44 is fixed to the lower surface of the lid body 24, and the left and right side extending portions 44A of the extending portion 44 are not fixed to the lower surface of the lid body 24. Also, in Embodiment 2, the first fixing portion 144C of the rearward extending portion 144B of the extending portion 144 is caulked and fixed to the caulking portion 27B of the housing main body 23 together with the lid body 24. Not limited to these examples, the scope of the present disclosure includes configurations in which at least a part of the left and right side extending portions and the rearward extending portion are fixed to the lid body or caulked and fixed to the caulking portion of the housing main body.

[0074] In the above-described embodiment, the water heaters 1 and 101 having a hot water supply circuit for heating tap water and discharging hot water have been exemplified. However, water heaters for other uses, such as those for circulation in a bathtub or central heating, may also be used.

[0075] Note that the scope of the present disclosure is not limited to the above-described embodiments, and it is intended that all modifications within the scope shown by the claims or within the scope equivalent to the claims are included.

Explanation of Reference Numerals

[0076] 1, 101... water heater, 2... outer casing, 3... inner cylinder, 4... burner device, 5... drain hose, 6... controller, 10... primary heat exchanger, 11... can body, 12... primary heat transfer pipe, 13... water inlet pipe, 14... hot water outlet pipe, 15... relay pipe 20, 120... secondary heat exchanger (heat exchanger) 21... heat transfer pipe, 21A... straight pipe portion, 21B... U-shaped pipe portion, 21C... first connection portion, 21D... second connection portion, 22, 122... housing, 23... housing main body portion, 23A... bottom wall portion, 23B... front wall portion, 23C... rear wall portion, 23D... right wall portion, 23E... left wall portion, 24... lid body, 24A... fixed portion, 25, 125... partition portion, 26... drain outlet, 27... fixing portion, 27A... flange portion, 27B... caulking portion, 27C... packing, 28... gas inlet, 29... connected portion, 33... right opening, 34... connected portion, 35... assembled body, 36... closing member, 36A... connecting member, 36B... packing, 37... first header, 37A... first header main body, 37B... first header lid body, 37C... joint cylinder, 37D... first bottom hole, 37E... first lid hole, 38... second header, 38A... second header main body, 38B... second header lid body, 38C... joint cylinder, 38D... second bottom hole, 38E... second lid hole, 39... bulging portion, 41... gas outlet, 42... exhaust pipe, 43... bottom plate, 43A... through hole, 44, 144... extending portion, 44A... side extending portion, 44B, 144B... rear extending portion, 44C, 144C... first fixing portion, 45... fixing piece, 45A... second fixing portion, 45B... extending portion, 46... opening, S1... internal space, S2... arrangement region, S3... upper region 50... path member 51…Path member body, 52…Rear part of the path member, 52A…Connecting member, 52B…Connecting member, 52C…Packing, 53…Opening, S4…Flow space

Claims

1. A heat exchanger that discharges combustion exhaust gas from above, comprising: a plurality of heat transfer tubes, and a housing in which the plurality of heat transfer tubes are disposed inside; the housing has a bottomed box shape with an open upper part, a gas inlet is formed in the rear wall part, and a fixed part having a flange part that extends in a flange shape from the peripheral edge part of the upper end part and a caulking part that extends to the outer edge part of the flange part. A housing main body part; a lid body having a gas outlet that opens upward on the top surface, and the outer peripheral edge part is caulked by the caulking part of the fixed part in a state of overlapping the upper side of the flange part of the fixed part to close the housing main body part; a partition part that is fixed to the lid body and partitions the internal space formed by the lid body and the housing main body part into a disposition area where the plurality of heat transfer tubes are disposed and an upper area that is disposed closer to the lid body than the disposition area and communicates with the gas outlet; the partition part includes a bottom plate disposed at a distance below the lid body, and extension parts extending from the left and right edge parts and the rear edge part of the bottom plate toward the lid body side; the front edge part of the lid body and the partition part constitutes an opening connecting the disposition area and the upper area; A heat exchanger, wherein at least a part of the extension part is fixed in a manner of contacting the lower surface of the lid body.

2. A heat exchanger that discharges combustion exhaust gas from above, comprising: a plurality of heat transfer tubes, and a housing in which the plurality of heat transfer tubes are disposed inside; the housing has a bottomed box shape with an open upper part, a gas inlet is formed in the rear wall part, and a fixed part having a flange part that extends in a flange shape from the peripheral edge part of the upper end part and a caulking part that extends to the outer edge part of the flange part. A housing main body part; a lid body having a gas outlet that opens upward on the top surface, and the outer peripheral edge part is caulked by the caulking part of the fixed part in a state of overlapping the upper side of the flange part of the fixed part to close the housing main body part; a partition part that is fixed to the lid body and partitions the internal space formed by the lid body and the housing main body part into a disposition area where the plurality of heat transfer tubes are disposed and an upper area that is disposed closer to the lid body than the disposition area and communicates with the gas outlet; the partition part includes a bottom plate disposed at a distance below the lid body, and extension parts extending from the left and right edge parts and the rear edge part of the bottom plate toward the lid body side; the front edge part of the lid body and the partition part constitutes an opening connecting the disposition area and the upper area; At least a part of the extended portion is sandwiched between the flange portion and the outer peripheral edge portion of the lid body, and the outer peripheral edge portion of the lid body is clamped by the clamping portion so as to be clamped by the flange portion and the outer peripheral edge portion of the lid body, a heat exchanger.

3. The partition portion extends from the front edge portion of the bottom plate toward the lid body and includes a fixing piece fixed to the lower surface of the lid body, the heat exchanger according to claim 1 or claim 2.

4. A burner device that generates combustion exhaust gas, and a heat exchanger according to any one of claims 1 to 3, a water heater.

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