JP2010127512A - Heat exchanger and water heating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger capable of properly suppressing the reduction of a heat collecting amount from a heating medium caused by the existence of clearances formed at adjacent regions of a plurality of coil tube units. <P>SOLUTION: In the heat exchanger, the plurality of coil tube units U are arranged in the axial direction, each coil tube unit U has a coil tubular body 3 constituted by connecting a plurality of loops 30 in series, and first and second extended tubular bodies 4A, 4B connected to both ends of the coil tubular body 3, and fluid circulated in the coil tubular body 3 can be heated by allowing the heating medium to pass between and among the plurality of loops 30 from one of an inner region and an outer region of the coil tubular body 3 toward the other. In the heat exchanger, at least a part of clearances 6 formed between the first and second extended tubular bodies 4A, 4B positioned in adjacent regions of the plurality of coil tube units U is closed by an auxiliary tubular body 8 constituted to circulate the fluid therein. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat exchanger that recovers heat from a heating medium such as combustion gas using a plurality of coil tube units, and a hot water device such as a hot water supply device including the heat exchanger.

  An example of a conventional heat exchanger is described in Patent Document 1. In the heat exchanger described in this document, the heat transfer tubes are configured using a plurality of coil tube units, and the plurality of coil tube units are arranged in the axial direction of the coils and arranged in the casing. ing. Each coil tube unit has a coil tube portion in which a plurality of spiral loop portions are connected in series, and a pair of extended tube portions connected to both ends of the coil tube unit. It is possible to allow water to flow from the extended tube portion into the coil tube portion. On the other hand, when the combustion gas is supplied to the inner regions of the plurality of coil tube units, the combustion gas acts on the coil tube portion while passing between the plurality of loop portions of the coil tube portion. Therefore, it is possible to recover the heat from the combustion gas by the coil tube part and to heat the water flowing through the coil tube part. If a heat transfer tube is configured using a plurality of coil tube units, the amount of heat recovered from the combustion gas can be changed as appropriate by increasing or decreasing the number of coil tube units, and the desired hot water heating capacity is exhibited. This makes it easier to design and manufacture the heat exchanger.

  However, the prior art has a problem to be solved as described below.

  That is, in the prior art, a coiled tube unit 9 as shown in FIGS. 9A and 9B is used. In the coil tube unit 9, first and second extending tube portions 91a and 91b extend in a tangential direction from both ends of a coil tube portion 90 as a circular spiral tube. A dimension L10 between the pair of extending tube portions 91a and 91b is as large as the inner diameter of the coil tube portion 90. In addition, a step h is generated between each of the extending tube portions 91a and 91b and the surface portion of the coil tube portion 90 located in the vicinity thereof. For this reason, as shown in FIG. 10, when the plurality of coil tube units 9 are arranged in the axial length direction, a gap 92 having a width L10 is formed in a region where they are adjacent to each other. In this case, when the combustion gas is supplied to the inside of each coil tube portion 90, most of the combustion gas passes through the gap 92, and the combustion gas effectively acts on each coil tube portion 90. The amount of heat recovery is reduced. In the example shown in FIGS. 9 and 10, the thickness of each part of the coiled tube body 90 is shown to be uniform, but in Patent Document 1, the thickness of each part of the coiled tube body is shown. A configuration is shown in which the gaps 92 are not generated as described above. However, in such a configuration, compared with the case where the thickness of each part of the coiled tube body part is formed uniformly, the manufacturing operation of the coiled tube body part becomes considerably troublesome and the manufacturing cost becomes high.

JP-T-2006-503260

  The present invention has been conceived under the circumstances described above, and the amount of heat recovered from the heating medium due to the presence of gaps formed in adjacent regions between the plurality of coil tube units. It is an object of the present invention to provide a heat exchanger capable of appropriately suppressing the decrease in the temperature and a hot water apparatus including the heat exchanger.

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

  The heat exchanger provided by the first aspect of the present invention includes a plurality of coil tube units arranged in the axial length direction, and each of the coil tube units has a plurality of loop portions connected in series. A coil tube section, and first and second extending tube sections connected to both ends of the coil tube section and extending outward from the coil tube section; When the heating medium passes between the plurality of loop portions from one of the inner region and the outer region to the other, the fluid flowing through the coiled tube portion can be heated. A heat exchanger in which a gap is formed between the first and second extending tube portions located in adjacent regions between the plurality of coil tube units, wherein the heating medium is the In order to suppress passing through the gap, Both are characterized by closing a portion, and to be capable of performing heat recovery from the heating medium that has progressed the auxiliary tube body portion fluid therein flows comprises further.

According to such a configuration, the following effects can be obtained.
First, since a gap formed between the first and second extending tube portions in the adjacent region between the coil tube units is closed by the auxiliary tube portion, the coil tube portion When the heating medium is passed from one of the inner region and the outer region toward the other, it is prevented that many heating media pass through the gap. Accordingly, it is possible to effectively apply a large amount of the heating medium to the coil tube body part, and the amount of heat recovered from the heating medium can be increased. In the present invention, when the heating medium that has advanced toward the gap comes into contact with the auxiliary tube body, heat is recovered from the heating medium by the auxiliary tube body. For this reason, the amount of heat recovered from the heating medium can be increased, and high heat exchange efficiency can be obtained.
Secondly, since fluid flows through the auxiliary tube body portion, it is prevented that the auxiliary tube body portion is overheated when heated by the heating medium. Therefore, the trouble that the auxiliary tube part is thermally damaged can be suitably avoided.
3rdly, compared with the heat exchanger described in patent document 1, the heat exchanger which concerns on this invention has increased the number of parts by the part which the auxiliary | assistant pipe | tube part was additionally provided. However, the auxiliary tube part can be manufactured in a very simple configuration by using, for example, a single tubular member. On the other hand, according to the present invention, unlike the above-mentioned Patent Document 1, the thickness of each part of the coil tube unit is formed unevenly, and the gap formed in the adjacent region between the coil tube units is reduced. There is no need to adopt means. Therefore, according to the present invention, even when the means described in Patent Document 1 is adopted, the manufacturing cost of the entire heat exchanger can be reduced.

  In a preferred embodiment of the present invention, the first and second extending tube portions located in adjacent regions between the plurality of coil tube units are formed so as to extend in a substantially normal direction of the loop portions. Being close to each other.

  According to such a structure, the clearance gap formed between the 1st and 2nd extending tubular-body parts in the adjacent area | region between coil tube units becomes small. Therefore, it is more preferable to suppress the heating medium from passing through the gap. In addition, the size of the auxiliary tube part for closing the gap can be reduced.

  In a preferred embodiment of the present invention, there is provided a header portion that has a water inlet and a hot water outlet, and causes the hot water supplied to the water inlet to flow through the plurality of coiled pipe units to be discharged from the hot water outlet. The auxiliary pipe part is connected to the header part so that a part of the hot water supplied to the water inlet circulates in the auxiliary pipe part and then reaches the hot water outlet. .

  According to such a configuration, since the hot water flow to the auxiliary pipe part is performed by effectively using the header part used for the hot water flow to the plurality of coil pipe units, the header dedicated to the auxiliary pipe part is used. There is no need to provide a separate section, which is reasonable. Moreover, according to the said structure, since the hot water heated by distribute | circulating through the inside of an auxiliary | assistant pipe | tube part will be mixed with the hot water heated by distribute | circulating the several coil pipe unit, it is used for a hot water supply use etc. It can be used effectively.

  In a preferred embodiment of the present invention, the auxiliary tube body portion includes a portion whose inner diameter is smaller than or smaller than the plurality of coil tube units, and the plurality of coil tubes. It is configured so that the hot water flow rate per unit time is smaller than that of the unit.

  According to such a configuration, it is appropriately prevented that the hot water flow rate in the auxiliary pipe body portion is larger than the hot water flow rate in the coil tube unit. Therefore, it is possible to prevent a problem that a large amount of hot water that has just been circulated through the auxiliary tube body and heated without passing through the coil tube unit is discharged from the outlet.

  In a preferred embodiment of the present invention, the auxiliary tube portion is configured as a finned tube including a heat transfer fin that closes the gap.

  According to such a configuration, it is possible to efficiently close the wide range of the gap by using the heat transfer fins, and it is more suitable for reducing the amount of the heating medium passing through the gap. .

  A hot water apparatus provided by the second aspect of the present invention includes a burner and a heat exchanger for performing heat recovery from the combustion gas generated by the burner to perform hot water heating. However, the heat exchanger provided by the first aspect of the present invention is used 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.

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

  1 to 6 show an example of a heat exchanger to which the present invention is applied, a hot water apparatus including the heat exchanger, and a configuration related thereto. As clearly shown in FIG. 1, the hot water device WH of the present embodiment includes a burner 1 and a heat exchanger HE. The burner 1 is, for example, a gas burner. A gas mixture of combustion air and fuel gas is supplied to the burner 1 using a fan (not shown), and this gas mixture is ignited by an ignition plug (not shown). Combustion is performed by operation. The burner 1 is disposed in a first space portion 7A described later of the heat exchanger HE.

  The heat exchanger HE includes a casing 2, a plurality of coil tube units U (U 1 to U 3) as heat transfer tubes accommodated in the casing 2, and an auxiliary tube body portion 8.

  The casing 2 has a peripheral wall portion 20 surrounding the periphery of the plurality of coiled tube units U, and at both ends in the horizontal direction, an insertion opening 21 for the burner 1 and a combustion gas discharge port 22 for which heat recovery has been completed. Is formed. The peripheral wall portion 20 is provided with a header portion 5 for allowing water to flow through the plurality of coil tube units U. A specific configuration of the header unit 5 will be described later.

  As shown in FIGS. 5 and 6, each coil tube unit U has two coil tube portions 3 (3 </ b> A and 3 </ b> B) having different winding diameters and having the same length in the axial length direction. Has a concentric lap winding configuration. Each coil tube portion 3 has a configuration in which a plurality of circular spiral loop portions 30 are connected in series, and a gap for allowing combustion gas to pass between the plurality of loop portions 30 is formed. Yes. First and second extending tube portions 4A and 4B are connected to both ends of each coil tube portion 3. In the present embodiment, each coil tube portion 3 and the first and second extending tube portions 4A and 4B connected to the coil tube portion 3 are formed by bending one metal tube, Each coil tube portion 3 and the first and second extending tube portions 4A and 4B are integrally connected. However, unlike this, the first and second extending tube portions 4A and 4B may be formed by using a separate tube from each coil tube portion 3 and connected to each other. it can.

  As clearly shown in FIG. 6, the first and second extending tube portions 4A and 4B extend in substantially the same direction as the normal line NL of the loop portion 30 so that they are substantially parallel to each other. It is bent and the first extending tube portion 4A and the second extending tube portion 4B are close to each other. In addition, the first and second extending tube portions 4A and 4B connected to the inner peripheral side coil tube portion 3A are provided between the first and second extended tube portions 3B. It is provided so that the interval L1 in the tangential direction of the loop portion 30 can be reduced without interposing the extending tube portions 4A and 4B. The distance L1 is small enough not to cause any trouble in connecting the first and second extending tube portions 4A and 4B to the header portion 5 to be described later. Since the portion 8 is arranged, the size is slightly larger than the outer diameter of the auxiliary tube portion 8.

  As shown in FIGS. 3 and 4, the plurality of coil tube units U <b> 1 to U <b> 3 are arranged so as to approach each other in the axial length direction thereof. In the hot water device WH of FIG. 1, a plurality of coil tube units U1 to U3 are arranged in a substantially horizontal direction, but for convenience, in FIGS. 3 and 4, they are shown in a vertically arranged posture. Among the plurality of coil tube units U1 to U3, a gap 6 is formed between the first and second extending tube portions 4A and 4B located in the adjacent region between the coil tube units U1 and U2. Yes. Similarly, a gap 6 is also formed between the first and second extending tube portions 4A and 4B located in the adjacent region between the coil tube units U2 and U3. The width of these two gaps 6 is the width L1 shown in FIG.

  The auxiliary tube portion 8 is a member for closing the two gaps 6 described above, and is configured using, for example, a metal tube made of the same material as each coil tube unit U. The intermediate portion in the longitudinal direction of the auxiliary tube portion 8 is interposed between the first and second extending tube portions 4A and 4B and contacts or approaches the outer surface of the plurality of coil tube portions 3B. Thus, it extends in the axial length direction of the plurality of coil tube units U, and thereby covers substantially the entire area of the two gaps 6. Both end portions 8a and 8b in the longitudinal direction of the auxiliary tube portion 8 extend in substantially the same direction as the first and second extending tube portions 4A and 4B, and the first and second extending tube bodies. It is connected to the header part 5 together with the parts 4A and 4B.

  The header portion 5 includes a front plate portion 55 having a water inlet 50 and a hot water outlet 51, and a base portion 56 that is joined to the front plate portion 55. Inside the header portion 5, A plurality of hot water inflow chambers 57a to 57d communicating with the first and second extending tube portions 4A and 4B are defined. When water enters the water inlet 50 from a water supply pipe (not shown), the water passes through the coil pipe units U1 to U3 in the order shown in FIG. The desired hot water supply destination is supplied through an appropriate pipe (not shown). Of course, the order of water flow to the plurality of coil tube units U is not limited to the order shown in FIG. The ends 8 a and 8 b of the auxiliary pipe body 8 are connected to a hot water inflow chamber 57 a that communicates with the water inlet 50 and a hot water inflow chamber 57 d that communicates with the hot water outlet 51, respectively. For this reason, a part of the water that has flowed into the hot water inflow chamber 57 a from the water inlet 50 flows into the hot water inflow chamber 57 d after passing through the auxiliary pipe part 8 and reaches the hot water outlet 51. . The auxiliary tube body portion 8 includes a portion (orifice) whose inner diameter is smaller than each coil tube unit U or whose inner diameter is partially reduced. As a result, hot water flows in the auxiliary tube portion 8 with a flow rate per unit time smaller than that of each coil tube unit U.

  As shown in FIG. 1, the plurality of coil tube units U are arranged in the casing 2 in a state where they are arranged side by side so that their axial length directions are substantially horizontal directions. As positioning means for the plurality of coil tube units U, a set of spacers 29a, 29b and other members (not shown) that sandwich them in the horizontal direction are appropriately used. A partition member 28 is provided between the coil tube units U2 and U3, and an inner region of the coil tube units U1 to U3 includes a first space portion 7A in which the burner 1 is disposed, and combustion gas. The second space portion 7 </ b> B communicating with the discharge port 22 is partitioned. As a result, the two coil tube units U1, U2 serve as a first heat exchanging portion H1 surrounding the first space portion 7A, and the remaining coil tube units U3 define the second space portion 7B. It becomes the surrounding 2nd heat exchange part H2.

  Next, the operation of the hot water device WH provided with the heat exchanger HE will be described.

  First, when the burner 1 is driven to generate combustion gas in the first space portion 7A, the combustion gas passes between the loop portions 30 of the first heat exchange portion H1 and performs first heat exchange. After proceeding to the outer peripheral region of the portion H1, the air passes through the loop portions 30 of the second heat exchange portion H2 and flows into the second space portion 7B, and then is discharged from the discharge port 22 to the outside of the casing 2. Is done. In such a process, sensible heat and latent heat are sequentially recovered from the combustion gas by the first and second heat exchanging units H1 and H2. Each of the first and second heat exchange parts H1, H2 is configured using coil tube parts 3A, 3B having a double winding structure, and each loop part 30 of the coil tube parts 3A, 3B includes: Since the coil tube portions 3A and 3B are formed using circular tubes (tubes having a circular cross-sectional shape) because they are aligned in the flow direction of the combustion gas, the amount of heat recovered from the combustion gas It is possible to increase. When latent heat is recovered from the combustion gas, the water vapor in the combustion gas is condensed, and the drain (condensed water) flows down from the second heat exchanging portion H2. Therefore, preferably, the peripheral wall portion 20 of the casing 2 has a drain outlet (not shown) for discharging the drain that has flowed down from the second heat exchange portion H2 onto the peripheral wall portion 20 to the outside of the casing 20. Is provided.

  In order to increase the amount of heat recovered by the plurality of coil tube portions 3, it is desired that most of the combustion gas generated in the first space portion 7A does not pass through the two gaps 6. On the other hand, in the heat exchanger HE of the present embodiment, the auxiliary tube portion 8 blocks the gaps 6, and a large amount of combustion gas is preferably prevented from passing through the gaps 6. Therefore, most of the combustion gas generated by the burner 1 in the first space portion 7A normally passes between the plurality of loop portions 30, and the amount of heat recovered by the plurality of coil tube portions 3 is increased. It becomes possible. In addition, a part of the combustion gas acts on the auxiliary pipe part 8, and then, heat recovery from the combustion gas is performed by the auxiliary pipe part 8, and the hot water flowing in the auxiliary pipe part 8 is heated. The Therefore, the amount of heat recovered from the combustion gas can be increased, and high heat exchange efficiency can be achieved. Further, if hot water is circulated in the auxiliary tube portion 8, the auxiliary tube portion 8 is prevented from being overheated due to the heat of the combustion gas, and the auxiliary tube portion 8 is thermally damaged. You can also avoid it.

  In the present embodiment, the first and second extending tube portions 4A and 4B located in the adjacent region between the coil tube units U1 and U2 and the first located in the adjacent region between the coil tube units U2 and U3. The second extending tube portions 4A and 4B extend in substantially the same direction as the normal direction of each loop portion 30 and are close to each other, and an opening of the gap 6 formed between them. The width L1 is originally reduced (see also FIGS. 3 and 6). Therefore, it is not necessary to use, for example, a large diameter tube as the auxiliary tube portion 8 for closing the gap 6, and the cost of parts can be reduced. Further, even if the entire gap 6 is not completely closed by the auxiliary tube portion 8, it is possible to reduce the amount of combustion gas passing through the gap 6. It is more preferable for the gas to act effectively.

  Since the water flow to the auxiliary pipe body portion 8 is performed using the header portion 5 used for water flow to the plurality of coil tube units U, the overall size of the heat exchanger HE is increased. It is preferably suppressed. In addition, since hot water flows in the auxiliary pipe body 8 with a flow rate per unit time smaller than that of each coil tube unit U, the hot water flow rate in each coil tube unit U becomes insufficient. Is also preferably avoided.

  7 and 8 show another embodiment of the present invention. 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 embodiment shown in FIG. 7, the auxiliary tube portion 8 </ b> A is configured as a finned tube provided with heat transfer fins 81. The fin 81 has, for example, a rectangular shape extending in substantially the same direction as the intermediate portion in the longitudinal direction of the main body portion (main body tube) 80 of the auxiliary tube portion 8A, and has a shape and size capable of closing the substantially entire gap 6. Is formed. According to the present embodiment, it is possible to easily and accurately close the gap 6 as compared with the case where an auxiliary tube body using only a tube material having no fins is used. Of course, two fins 81 may be provided corresponding to each of the two gaps 6. In the present invention, when the auxiliary tube portion is configured as a finned tube as in this embodiment, the fin closes the gap 6 and the main body portion (main body tube) of the auxiliary tube portion has the gap 6. An unblocked configuration is also possible, and such a configuration is also included in the technical scope of the present invention.

  In the embodiment shown in FIG. 8, the gap 6 is closed by using a plurality of (two in the drawing) auxiliary tube portions 8. As will be understood from the present embodiment, in the present invention, the number of auxiliary tube portions 8 for closing the gap 6 may be either one or a plurality. In FIG. 8, the two auxiliary tube portions 8 are arranged in parallel, but instead of this, a configuration in which they are arranged in series (for example, as shown in FIG. 4, two gaps 6 are arranged in the vertical direction. When formed, the upper gap 6 may be closed by one auxiliary tube portion 8 and the lower gap 6 may be closed by another auxiliary tube portion 8).

  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.

  The auxiliary tube part referred to in the present invention can also be configured using, for example, a flexible tube. According to such a configuration, it is possible to provide flexibility when the operation of connecting the auxiliary tube body portion to the header portion is performed at a predetermined position, thereby facilitating the work of assembling the auxiliary tube body portion. It becomes suitable for.

  The auxiliary tube portion needs to be provided so as to close a gap formed between the first and second extending tube portions located in the adjacent region between the plurality of coil tube units. As used herein, the term “blocking the gap” means that at least a part of the gap is blocked so that the heating medium is prevented from passing through the gap. It does not matter if the whole is not blocked. Moreover, the auxiliary tube part does not necessarily have to be disposed inside the gap. For example, even when the auxiliary tube portion is disposed so as to face the front of the gap, it corresponds to “block the gap” as long as passage of the heating medium through the gap is suppressed. Therefore, in the present invention, instead of the configuration in which the auxiliary tube portion is disposed in the outer region of the coil tube portion, the auxiliary tube portion is disposed in the inner region of the coil tube portion so as to face the gap. It is also possible to adopt a configuration.

  The tubular body constituting the coil tube unit is not limited to a tubular body having a circular cross section, and for example, a tubular body having an elliptical cross section or a flat tubular body similar to Patent Document 1 can be used. A specific cross-sectional shape and the like are not limited. In addition, as the coil tube unit, any one of a plurality of coil tube bodies having a substantially concentric lap winding shape and a single layer structure in which such lap winding is not performed can be used. . In the case of the former lap winding structure, it is possible to have a lap winding structure of triple winding or more. When recovering latent heat from combustion gas, an acidic drain is generated. Therefore, it is preferable to make the coil tube unit a material having excellent acid resistance, such as stainless steel, but the specific material of the coil tube unit is also used. It is not limited to this.

  As shown in FIG. 1, when a plurality of coil tube units are provided side by side, each loop portion of the coil tube body portion is in an upright posture, which is generated along with latent heat recovery. Although an advantage that the drain can easily flow down from each loop portion is obtained, the present invention is not limited to this. In this invention, it can also be set as the structure which put in order in the attitude | position which laminated | stacked the several coil tube unit in the up-down direction (substantially perpendicular direction), or in the inclined attitude | position. The total number of coil tube units should just be plural, and the concrete number is not ask | required.

  As the heating medium in the present invention, for example, high-temperature waste gas other than the combustion gas can be used. Further, the fluid to be heated (fluid supplied to the coil tube unit and the auxiliary tube body) can also be a fluid other than water. 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.

It is sectional drawing which shows an example of the heat exchanger which concerns on this invention, and a warm water apparatus provided with the same. It is II-II sectional drawing of FIG. It is a principal part disassembled perspective view of the heat exchanger shown in FIG. It is a principal part disassembled perspective view of the heat exchanger shown in FIG. It is a perspective view which shows the coiled tube unit used with the heat exchanger shown in FIG. FIG. 6 is a plan view of FIG. 5. (A) is a principal part plane sectional view showing other examples of the present invention, and (b) is an exploded perspective view of (a). It is principal part plane sectional drawing which shows the other example of this invention. (A) is a top view which shows an example of the conventional coiled tube unit, (b) is the perspective view. FIG. 10 is a front view showing a state in which a plurality of coil tube units shown in FIG. 9 are arranged.

Explanation of symbols

WH Hot water apparatus HE Heat exchanger U Coil tube unit NL Normal line 1 Burner 2 Casing 3 Coil tube portions 4A and 4B First and second extending tube portions 5 Header portion 6 Clearance (first and second extension) (Between tube parts)
8,8A Auxiliary tube part 30 Loop part 50 Water inlet 51 Hot water outlet

Claims (6)

It has a plurality of coil tube units arranged in the axial direction,
Each of the coil tube units includes a coil tube portion in which a plurality of loop portions are connected in series, and first and second portions that are connected to both ends of the coil tube portion and extend outward of the coil tube portion. And an extended tube part,
The heating medium passes between the plurality of loop portions from one of the inner region and the outer region of the coil tube portion toward the other, so that the fluid flowing through the coil tube portion can be heated. And
A heat exchanger in which a gap is formed between the first and second extending tube portions located in adjacent regions between the plurality of coil tube units,
Auxiliary tube part that closes at least a part of the gap so as to prevent the heating medium from passing through the gap and allows heat recovery from the heating medium that has progressed. And a heat exchanger. The heat exchanger according to claim 1,
The first and second extending tube portions located in adjacent regions between the plurality of coil tube units are formed so as to extend in a substantially normal direction of the loop portions, and are close to each other. vessel. The heat exchanger according to claim 1 or 2,
A header part for having a water inlet and a water outlet, and for circulating hot water supplied to the water inlet to the plurality of coiled tube units to discharge the hot water from the outlet;
The auxiliary pipe part is connected to the header part so that a part of hot water supplied to the water inlet circulates in the auxiliary pipe part and then reaches the outlet. . The heat exchanger according to claim 3,
The auxiliary tube body has a portion whose inner diameter is smaller than the plurality of coil tube units, or a portion whose inner diameter is partially smaller, and the hot water flow rate per unit time than the plurality of coil tube units. The heat exchanger is configured to reduce the amount of heat. The heat exchanger according to any one of claims 1 to 4,
The auxiliary tube portion is a heat exchanger configured as a finned tube including a heat transfer fin that closes the gap. A hot water apparatus comprising a burner and a heat exchanger for performing heat recovery from combustion gas generated by the burner to perform hot water heating,
A hot water apparatus, wherein the heat exchanger according to any one of claims 1 to 5 is used as the heat exchanger.

Images