JP5742073B2 - Heat exchanger and hot water device provided with the same - Google Patents

Description

  The present invention relates to a heat exchanger of a type that recovers heat from a heating gas such as combustion gas using a heat transfer tube, and a hot water device such as a hot water supply device equipped with the heat exchanger.

  The present applicant has previously proposed the one described in Patent Document 1 as an example of a heat exchanger. The heat exchanger described in this document has a configuration in which a plurality of heat transfer tubes are accommodated in a casing in which a combustion gas supply port and an exhaust port are formed. Each heat transfer tube is a spiral heat transfer tube, and has a form in which a plurality of loop portions having an oval shape in plan view are stacked with a gap in the vertical direction. This heat transfer tube is manufactured by bending a metal pipe. The combustion gas that has flowed into the casing passes through gaps formed between the plurality of loop portions, and contacts the heat transfer tubes at that time. By this action, heat is recovered from the combustion gas, and hot water flowing through the heat transfer tube is heated. According to the heat exchanger having such a configuration, it is possible to increase the heat transfer area while reducing the size of the entire heat transfer tube as compared with the heat exchanger using the heat transfer tube of the straight tube type. Is possible. Therefore, high heat exchange efficiency can be obtained while suppressing an increase in the size of the entire heat exchanger.

  However, the prior art still has room for improvement as described below.

  That is, in the technical field of heat exchangers, it is desired to further increase the heat exchange efficiency while suppressing the increase in size and cost of the heat exchanger. In the conventional heat exchanger, it is possible to further increase the heat exchange efficiency by increasing the length of the plurality of heat transfer tubes, but the heat exchange efficiency is increased only by increasing the length of the heat transfer tubes. If it is going to do, a heat exchanger will enlarge and manufacturing cost will also become high. Therefore, there is room for improvement in this respect. In addition, as another means for responding to the above-described demand, for example, it may be possible to increase the heat transfer area by providing a large number of fins on the outer surface of the heat transfer tube. However, when such a means is adopted, the operation of providing a large number of fins on the heat transfer tube is not easy and is considerably complicated, resulting in an increase in cost. In particular, since it is not easy to provide a large number of fins in a spiral heat transfer tube, the above-described problems become more prominent.

JP 2007-333343 A

  The present invention has been conceived under the circumstances as described above, and is capable of improving heat exchange efficiency as compared with conventional heat exchange while appropriately suppressing increase in size and production cost. An object of the present invention is to provide a hot water apparatus including a heat exchanger and a heat exchanger.

  In order to solve the above problems, the present invention takes the following technical means.

A heat exchanger provided by the first aspect of the present invention includes a casing provided with a supply port and an exhaust port for heating gas, and is bent in the casing and bends a metal pipe. A plurality of heat transfer tubes in which a plurality of bent tube portions are formed, and the plurality of heat transfer tubes have a plurality of substantially rectangular loop portions in plan view with gaps in the vertical height direction. A plurality of laminated spiral heat transfer tubes, and each loop portion includes a pair of straight tube portions extending in the front-rear direction of the casing, and another pair of straight tube portions extending in the left-right width direction of the casing. Are connected to each other, and the plurality of spiral heat transfer tubes are arranged in a substantially concentric overlapping shape, and each of the plurality of spiral heat transfer tubes is configured as described above. The heating gas is passed through the gap. Is, a heat exchanger, the plurality of radii of curvature of the curved pipe section, identical to and aligned, wherein the plurality of inner surfaces of the curved pipe section, surface corrugated bending member On the other hand, the corrugated portion is not provided on the outer surface of the plurality of bent pipe portions, and the plurality of the curved pipe portions are provided along the line. The spiral heat transfer tube has a region in which the plurality of bent tube portions are arranged in the overlapping winding direction, and in this region, the bent tube portions adjacent to each other in the overlapping winding direction are bent tube portions located inside. The outer surface and the corrugated portion on the inner surface of the bent tube portion located outside are configured to face each other .

  According to such a configuration, in addition to the effect of increasing the surface area of the heat transfer tube due to the presence of the corrugated portion, turbulence of the heating gas is promoted when the heating gas proceeds toward the corrugated portion. The residence time of the heating gas in the vicinity of the corrugated portion becomes longer, and the effect of increasing the chance that the heating gas contacts the heat transfer tube is obtained. As a result, the amount of heat recovered by the heat transfer tube can be increased. On the other hand, the corrugated portion is formed on the inner surface of the bent portion of the heat transfer tube, and is unlikely to cause an increase in the size of the entire heat transfer tube. In addition, the corrugated portion is formed at the same time when a metal pipe is bent to manufacture a heat transfer tube, and an extra work step for forming the corrugated portion is unnecessary. The forming operation is also easy. For this reason, according to the present invention, it is possible to obtain a higher heat exchange efficiency than that of the conventional technique while suppressing an increase in the size of the heat transfer tube, an increase in the size of the heat exchanger and an increase in manufacturing cost.

According to the configuration described above, it is possible to promote the turbulence of the heating gas due to the presence of the corrugated portion in the vicinity of the curved tube portion connected to both ends of the straight tube portion of the heat transfer tube. For this reason, not only the straight tube portion of the heat transfer tube but also the heat recovery that efficiently utilizes the bent tube portions connected to both ends thereof is possible.

  The hot water apparatus provided by the second aspect of the present invention includes a heating gas supply means, a heat exchanger for performing hot water heating using the heating gas supplied from the heating gas supply means, It is characterized by using the heat exchanger provided by the 1st side surface of the present invention as the heat exchanger.

  According to such a configuration, the same effect as described for the heat exchanger provided by the first aspect of the present invention can be obtained.

  Other features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention with reference to the accompanying drawings.

It is a schematic front sectional view showing an example of a hot water device. It is a plane sectional view of the heat exchanger used for the hot water device shown in FIG. It is III-III principal part sectional drawing of FIG. (A), (b) is explanatory drawing which shows the process of manufacturing the heat exchanger tube of the heat exchanger shown in FIG. It is a plane sectional view showing an example of a heat exchanger concerning the present invention. Other examples of heat exchangers is a plan sectional view showing a. It is VII-VII sectional drawing of FIG. It is a side sectional view showing another example of heat exchangers. Other examples of heat exchangers is a plan sectional view showing a. It is a plan view showing another example of the heat transfer tubes used in heat exchangers. Other examples of heat exchangers is a plan sectional view showing a. Other examples of heat exchangers is a plan sectional view showing a. It is a plan view showing another example of the heat transfer tubes used in heat exchangers.

  Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

1 to 4 show an example of a water heater, and this related configuration with heat exchangers.
The hot water device WH of the present embodiment is configured as a hot water supply device, and the overall basic configuration is the same as that of the hot water supply device described in Patent Document 1. As shown in FIG. 1, the hot water device WH includes a combustor 3, a primary heat exchanger 1, and a secondary heat exchanger A1 .

  The combustor 3 is, for example, a gas burner, and burns fuel gas that is disposed in the can body 30 and that is supplied into the can body 30 from the outside via a pipe (not shown). The combustor 3 corresponds to an example of a heating gas supply means in the present invention. Combustion air is blown upward from the fan 31 into the can 30. The primary heat exchanger 1 is for recovering sensible heat from the combustion gas generated by the combustor 3, and includes a plurality of heat transfer tubes 11 having a plurality of fins 12, for example. Each heat transfer tube 11 is a straight tube and is different from the heat transfer tube 4 described later of the secondary heat exchanger A1, and therefore, the operation of providing the fins 12 is relatively easy, and the manufacturing cost thereof is not so expensive. .

  The secondary heat exchanger A <b> 1 is for further recovering latent heat from the combustion gas from which sensible heat has been recovered by the primary heat exchanger 1, and is disposed on the can body 30. The secondary heat exchanger A1 includes a plurality of heat transfer tubes 4, a casing 2 that accommodates the plurality of heat transfer tubes 4, and a pair of headers 48 and 49 for incoming and outgoing hot water.

  As shown in FIG. 2, each of the plurality of heat transfer tubes 4 has a spiral shape having a plurality of loop portions 40 having an oval shape in plan view. The basic configuration of each heat transfer tube 4 is the same as that of the heat transfer tube described in Patent Document 1, and each loop portion 40 extends in the width direction intermediate region Sa in the left-right lateral width direction of the casing 2 and is substantially parallel. A pair of straight pipe portions 40a and 40b arranged in a simple manner, and semicircular arc shaped bent pipe portions 40c and 40d connected to both ends of the straight pipe portions 40a and 40b in the region Sb near the end in the width direction. It is the structure where is located. The plurality of loop portions 40 are connected in series and stacked in a vertical height direction via a plurality of gaps 46 (see FIG. 1). However, a corrugated portion 45 to be described later is provided on the inner side surfaces of the curved pipe portions 40c and 40d.

  The plurality of heat transfer tubes 4 are formed such that the sizes of the respective loop portions 40 are different from each other, and these are arranged in a substantially concentric wrapping shape. Extending tube portions 41 and 42 penetrating either one of the pair of side wall portions 20e and 20f of the casing 2 are connected to the lower end and the upper end of each heat transfer tube 4, and these extended tube portions 41 and 42 are connected. Headers 48 and 49 are attached to the outer ends of the. As clearly shown in FIG. 1, the outlet of the header 49 is connected to the inlet 11 a of the heat transfer tube 11 through an appropriate pipe 99. A water supply pipe 98 is connected to the water inlet of the header 48. The water supplied from the water supply pipe 98 to the header 48 is sequentially passed through the plurality of heat transfer pipes 4 and 11 and heated, and then supplied from the hot water outlet 11b to a desired hot water supply destination.

Each heat transfer tube 4 is formed by bending a metal pipe. When latent heat is recovered from the combustion gas, strongly acidic condensed water is generated. Therefore, each heat transfer tube 4 is preferably made of a material such as stainless steel having excellent acid resistance. When manufacturing the heat transfer tube 4, as shown in FIG. 4 (a), a straight metal pipe 4 'is used as a raw material of the heat transfer tube 4, and the surface is wave-shaped as a bending tool. The formed bending member 8 is used. From the viewpoint of reducing the raw material cost, the metal pipe 4 ′ is preferably a simple cylindrical pipe whose surface and inner surface are not specially processed. As shown in FIG. 4B, the bent pipe portion 40c or 40d is formed by bending the metal pipe 4 ′ along the surface of the bending member 8 (in the figure, the bent pipe is shown. The intermediate stage in which the part 40c or 40d is formed is shown). A plurality of members having different curvature radii on the outer surface are used as the bending member 8 and the above-described bending process is repeated to form the elliptical heat transfer tube 4 in plan view. Is possible. In the heat transfer tube 4 of the present embodiment, a corrugated portion 45 corresponding to the surface shape of the bending member 8 is formed on the inner surface of the bent tube portions 40c and 40d. The corrugated portion 45 is a concavo-convex shape in which a plurality of streaky portions protruding in a fin shape are arranged at substantially constant intervals.

  The casing 2 has a hollow, substantially rectangular parallelepiped shape, and is made of, for example, stainless steel like the heat transfer tube 4. As shown in FIG. 3, an air supply port 21 is provided in the rear wall portion 20 c of the casing 2, and the combustion gas that has passed through the primary heat exchanger 1 is guided to the air supply port 21 by the auxiliary member 19. It is like that. The air supply port 21 is disposed so as to face the straight tube portion 40 a of the heat transfer tube 4, and the combustion gas flowing into the casing 2 from the air supply port 21 proceeds toward the front portion in the casing 2 as it is. This acts on each part of the heat transfer tube 4 to recover heat. An exhaust port 22 is provided in the front wall portion 20d of the casing 2, and the combustion gas whose heat has been recovered is discharged from the exhaust port 22 to the outside as exhaust gas.

  A partition plate 38 is provided between the exhaust port 22 and the heat transfer tube 4. The partition plate 38 has a function of suppressing combustion gas that has progressed from the air supply port 21 into the casing 2 to linearly travel toward the exhaust port 22 and is discharged outside the casing 2. By providing the partition plate 38, most of the combustion gas that has flowed into the casing 2 from the air supply port 21 can be advanced toward the end region Sb of the heat transfer tube 4. Further, the partition plate 38 is useful for preventing the condensed water adhering to the heat transfer tube 4 from being blown off toward the exhaust port 22 by the combustion gas. Of course, in this invention, it can also be set as the structure by which such a partition plate 38 is not provided.

  Next, the operation of the hot water device WH will be described.

  First, when the combustor 3 is driven to generate combustion gas, the combustion gas is recovered from the sensible heat by the primary heat exchanger 1 and then into the casing 2 from the air inlet 21 of the secondary heat exchanger A1. Inflow. Then, the combustion gas passes through the gaps 46 of the plurality of heat transfer tubes 4 and reaches the exhaust port 22 before being discharged to the outside. In such a process, latent heat is recovered from the combustion gas by the heat transfer tubes 4, and hot water is heated.

  Since each heat transfer tube 4 has a configuration in which the corrugated portion 45 is provided on the inner surface of the bent tube portions 40c and 40d, the surface area (heat transfer area) of each heat transfer tube 4 increases. The following effects can also be obtained. That is, when the combustion gas travels toward the corrugated portion 45, turbulence of the combustion gas is promoted, and the combustion gas stays in the vicinity of the region Sb near the width direction end of each heat transfer tube 4 for a long time. The effect of increasing the contact frequency between the combustion gas and the bent tube portions 40c and 40d is obtained. Therefore, the amount of heat recovered by the bent tube portions 40c, 40 heat transfer tubes can be increased. In addition, since the air supply port 21 faces the straight tube portion 40a in the center region Sa in the width direction of each heat transfer tube 4, each straight tube portion 40a originally has a large amount of heat recovery. For this reason, in the present embodiment, the entire area of the heat transfer tube 4 is effectively used for heat recovery, and high heat exchange efficiency can be obtained.

  On the other hand, the corrugated portion 45 is not large and bulky on the inner side surfaces of the bent tube portions 40c, 40d of the heat transfer tube 4, and does not cause an increase in the size of the entire heat transfer tube 4. Further, as described with reference to FIG. 4, the corrugated portion 45 is formed at the same time when the bent pipe portions 40 c and 40 d are manufactured by bending the metal pipe 4 ′. It is possible to easily manufacture the heat transfer tube 4 with the same number of steps as the manufacturing operation process of the heat transfer tube. From such a thing, the enlargement of secondary heat exchanger A1 and the raise of manufacturing cost can also be suppressed appropriately.

5 to 13 show other embodiments. In these drawings, elements that are the same as or similar to those in the above embodiment are given the same reference numerals as in the above embodiment.

  In the heat exchanger A2 shown in FIG. 5, each heat transfer tube 4A is formed in a spiral shape having a loop portion 40A having a substantially rectangular shape in plan view. More specifically, both end regions in the width direction of the heat transfer tubes 4 have relatively short straight tube portions 40e and 40f extending in the front-rear direction of the casing 2, and these straight tube portions 40e and 40f. And the straight pipe portions 40a and 40b extending in the width direction of the casing 2 are integrally connected via the curved pipe portion 40g. The curved pipe portion 40g in the present embodiment has a ¼ arc shape. Preferably, the curvature radius of each of the plurality of curved pipe portions 40g is equal to each other at the same size. If the curvature radii are the same, it is possible to sequentially form all of the plurality of bent pipe portions 40g in the same work process using one kind of bending apparatus. A corrugated portion 45 similar to that shown in the previous embodiment is provided on the inner surface of each curved pipe portion 40g. In addition, in FIG. 5, the waveform process part 45 is simplified and shown typically. This also applies to FIG. 9 described later.

  Also in the present embodiment, since the corrugated portions 45 are provided at a plurality of locations near the end in the width direction of each heat transfer tube 4A, the turbulence of the combustion gas is promoted in the vicinity thereof, and the residence time of the combustion gas Can be lengthened. Therefore, it is possible to recover heat by effectively using the region near the end of each heat transfer tube 4A, and high heat exchange efficiency can be obtained. If the heat transfer tubes 4 are formed in a substantially rectangular shape in plan view, the heat transfer tubes 4 can be arranged at the four corners of the casing 2 or in the vicinity thereof, so the dead space in the casing 2 is reduced. The overall length of the heat transfer tube 4 can be increased.

  In the heat exchanger A3 shown in FIGS. 6 and 7, an air supply port 21 is provided in the bottom wall portion 20 a of the casing 2. Further, a combustion gas guide member 5 is provided in an inner region 25 of the innermost heat transfer tube 4 (region surrounded by the innermost heat transfer tube 4). In this heat exchanger A3, the combustion gas flows into the region 25 from the air supply port 21, and thereafter proceeds along a route as indicated by arrows N1 to N4. That is, the combustion gas that has flowed into the region 25 travels toward the rear portion in the casing 2 as indicated by the arrow N1 by the guide action of the guide member 5, and reaches the rear wall portion 20c of the casing 2 as indicated by the arrow N2. collide. Then, the combustion gas subsequently travels forward in the casing 2 and passes through both sides of the guide member 5 as indicated by an arrow N3 in FIG. A part of the combustion gas also passes through a gap 25b between the upper portion 5a of the guide member 5 and the upper wall portion 20b of the casing 2 as indicated by an arrow N3 'in FIG. Thus, the combustion gas that has advanced to the front side in the casing 2 is discharged from the exhaust port 22 to the outside of the casing 2 as indicated by an arrow N4.

  According to the present embodiment, since the combustion gas travels as indicated by the arrow N3, a large amount of combustion gas is efficiently and reliably supplied to the curved pipe portions 20c and 20d in the region near the end of the heat transfer tube 4. It is possible to proceed. On the other hand, since the curved pipe portions 20c and 20d located in the region near the end of the heat transfer tube 4 have the corrugated portion 45, they are recovered from the combustion gas by the region near the end of the heat transfer tube 4. It becomes more preferable to increase the amount of heat.

In the heat exchanger A4 shown in FIG. 8, an air supply port 21 is provided at a position closer to the rear than the heat transfer tube 4 in the bottom wall portion 20a of the casing 2. The combustion gas that has flowed into the casing 2 from the air supply port 21 then travels forward and acts on each heat transfer tube 4. As a means for causing the combustion gas to advance in a substantially horizontal direction and acting on the heat transfer tube, for example, a structure as in this embodiment can be adopted instead of the means shown in FIGS.

  In the heat exchanger A5 shown in FIG. 9, the heat transfer tube 4B has a meandering shape. More specifically, the heat transfer tube 4B has a plurality of straight tube portions 40h and a plurality of curved tube portions 40i, which are connected in series so as to meander in a plan view. A corrugated portion 45 is provided on the inner side surface of each curved pipe portion 40i. Also in the present embodiment, when the combustion gas flowing into the casing 2 from the air supply port 21 proceeds to the position of each curved pipe portion 40i, the turbulent flow of the combustion gas is promoted, and each curved pipe portion 40i and It is possible to increase the amount of heat recovered by the vicinity thereof, and the same effect as in the previous embodiment using a spiral heat transfer tube can be obtained. In the present embodiment, a combustion gas supply method in which the air supply port 21 and the guide member 5 are combined is adopted as in the embodiment shown in FIGS. 6 and 7, but a meandering heat transfer tube is used. Of course, the combustion gas supply system is not limited to this.

A heat transfer tube 4C shown in FIG. 10 is a spiral heat transfer tube having a circular shape in plan view. In this heat transfer tube 4C, the entire loop portion 40C corresponds to a curved tube portion. For this reason, the waveform processing part 45 is provided in the whole inner peripheral surface of the loop part 40C .

  The embodiment shown in FIGS. 11 to 13 shows a specific example in the case where the corrugated portion is not provided in all the curved portions of the heat transfer tube, but the corrugated portion is provided only in a specific curved portion. ing.

  That is, in the heat exchanger A1 ′ shown in FIG. 11, the corrugated portion 45 is provided in the region Sc near the combustion gas supply port 21 in the region Sb near the end of the heat transfer tube 4. The waveform processing part 45 is not provided in the region Sd close to the exhaust port 22. The other configuration is the same as that of the heat exchanger A1 described above. As in FIG. 11, in the heat exchanger A2 ′ shown in FIG. 12, the corrugated portion 45g in the region near the exhaust port 22 is not provided in the curved portion 40g near the end of the heat transfer tube 4A. . The other configuration is the same as that of the heat exchanger A2 described above. In addition, contrary to the configuration shown in FIGS. 11 and 12, a configuration in which the corrugated portion 45 is provided in the region near the exhaust port 22 and the corrugated portion 45 is not provided in the region near the air supply port 21. It is also possible to do. In the heat transfer tube 4 </ b> C ′ shown in FIG. 13, the corrugated portion 45 is provided only in the central region Se, and the corrugated portion 45 is not provided in other regions. The other configuration is the same as that of the heat transfer tube 4C described above.

  According to the embodiments shown in FIGS. 11 to 13, the residence time of the combustion gas in the casing 2 of the heat exchanger can be slightly shortened, and the residence time of the combustion gas is increased to increase the heat exchange efficiency. Therefore, the present invention can be effectively applied as a means for setting an optimum condition or a condition close to this condition. In addition, when providing the curved pipe part in which the waveform processing part is provided in one heat exchanger tube, and the curved pipe part in which the waveform processing part is not provided, the surface is a wave shape as a bending process member. Needless to say, it is only necessary to use two types of members, i.e., those formed in the above and those not formed.

  The present invention is not limited to the contents of the above-described embodiment. The specific configuration of each part of the heat exchanger and the hot water apparatus according to the present invention can be varied in design in various ways.

From the viewpoint of improving the heat exchange efficiency, the corrugated portion referred to in the present invention is preferable as the corrugation (concave / convex) has a large height difference and the greater the number thereof, but the specific contents thereof are not limited. The corrugated portion is, in essence, a metal pipe that is a raw material of the heat transfer tube, which is attached by bending the surface along a wave-shaped bending member, and the effect intended by the present invention, That is, it may be a wave shape (uneven shape) to the extent that it can exhibit the function of promoting turbulence of the heating gas. When a plurality of bent tube portions are provided in the heat transfer tube, a corrugated portion is provided in a part of the plurality of bent tube portions as understood from the embodiments shown in FIGS. Even when a bent pipe portion is included, it is included in the technical scope of the present invention.

  The casing only needs to accommodate the helical tube portion of the heat transfer tube, and a heating gas such as combustion gas may flow into the casing, and the specific shape and size thereof are not limited. In the above-described embodiment, the present invention is not applied to the primary heat exchanger for sensible heat recovery, but the heat exchanger according to the present invention may be of any type for sensible heat recovery and latent heat recovery. . The heat exchanger according to the present invention can also be used for sensible heat recovery. The hot water device as used in the present invention means a device having a function of generating hot water, and is used for various types of hot water supply devices for general hot water supply, bath hot water supply, heating, snow melting, and the like, and hot water supply. It is a concept that includes a wide range of equipment for producing hot water. As the heating gas, other than the combustion gas, for example, a gas engine for cogeneration or exhaust gas from a fuel cell can be used.

WH Hot water devices A1 to A5, A1 ', A2' Heat exchanger 2 Casing 3 Combustor (heating gas supply means)
4, 4A to 4C, 4C 'Heat transfer tube 8 Bending member 21 Air supply port 22 Exhaust port 40, 40A to 40C Loop portion (of heat transfer tube)
40c, 40d Curved tube portion 40g, 40i Curved tube portion 45 Waveform processing portion

Claims (2)

A casing provided with an inlet and an outlet for a heating gas;
A plurality of heat transfer tubes arranged in the casing and formed with a plurality of bent tube portions by bending the metal pipe; and
Equipped with a,
The plurality of heat transfer tubes are a plurality of spiral heat transfer tubes in which a plurality of loop portions having a substantially rectangular shape in plan view are stacked via a gap in the vertical direction, and each loop portion is a front-rear direction of the casing The four corner portions connecting the pair of straight tube portions extending to the other pair of straight tube portions extending in the left-right width direction of the casing are the plurality of curved tube portions,
The plurality of spiral heat transfer tubes are arranged in a substantially concentric wrapping shape, and are configured such that the heating gas passes through the gaps in each of the plurality of spiral heat transfer tubes . Because
The radii of curvature of the plurality of curved pipe portions are the same,
The plurality of inner surfaces of the curved pipe section, while the corrugated portion attached by bending the metallic pipe surface along a wave-shaped bending members are arranged, the plurality of songs There is no corrugated part on the outer surface of the pipe part,
The plurality of spiral heat transfer tubes have a region in which the plurality of curved tube portions are arranged in the overlapping winding direction, and in this region, the curved tube portions adjacent to each other in the overlapping winding direction are located inside. A heat exchanger characterized in that an outer side surface of a curved pipe part and a corrugated part on the inner side surface of the curved pipe part located on the outside are configured to face each other . A hot water apparatus comprising: a heating gas supply means; and a heat exchanger for performing hot water heating using the heating gas supplied from the heating gas supply means,
The hot water apparatus according to claim 1, wherein the heat exchanger according to claim 1 is used as the heat exchanger.

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