JP2011231945A - Hot water supply apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water supply apparatus capable of effectively preventing dew condensation on a bypass line.SOLUTION: While exhaust gas after passing through a heat exchanger 2 passes through an exhaust gas collection section 14 and an exhaust gas guide tube 15, combustion air in an inlet air introducing tube 16 and a supply air collection section 17 is heated by heat exchange. A bypass line 19 which connects a water supply line 3 to a hot water supply line 5 is disposed so as to pass through a clearance 20 defined between a supply air duct 18 which supplies heated combustion air to an air fan 6 and a burner case 10 whereby the bypass line 19 is heated by the heat of combustion air in the supply air duct 18. Alternatively, the bypass line 19 may be disposed so as to pass through the inside of the supply air duct 18.

Description

  The present invention relates to a hot water supply apparatus provided with a bypass pipe that connects between a water inlet pipe and a hot water outlet pipe, and particularly relates to a technique for preventing condensation on the bypass pipe.

  Conventionally, as a hot water supply apparatus, a water inlet pipe connected to the inlet side of the heat exchanger and a hot water outlet pipe connected to the outlet side are connected to each other by a bypass pipe, and the amount of water supplied to the heat exchanger is reduced by a bypass pipe. It has been proposed to reduce the amount of water to be bypassed to increase the temperature of the hot water from the heat exchanger and to prevent condensation of the heat exchanger by increasing the temperature of the hot water (see, for example, Patent Document 1). ).

  In addition, it has also been proposed to prevent condensation on the outer surface of the water inlet pipe by planting a large number of hairs such as resin fibers on the outer surface of the water inlet pipe that enters the heat exchanger (for example, patents). Reference 2).

JP 2005-265365 A Japanese Utility Model Publication No. 63-168760

  By the way, since cold water flows into the bypass pipe from the water inlet pipe and flows toward the hot water outlet pipe, there is a possibility that condensation occurs on the outer surface of the bypass pipe. In particular, when the water intake pipe and the hot water discharge pipe are arranged at positions separated from each other with the heat exchanger interposed, the extension of the bypass pipe is inevitably long in order to connect the two, and there is a possibility that condensation will occur. In addition to the increase, the region where condensation occurs is also expanded.

  For example, when the heat exchanger is configured as a fin-and-tube type consisting of a large number of fins and a plurality of tubes passing through them, the number of tubes communicated so as to fold through the fins. If the number is not an even number but an odd number, the starting point of the tube to which the inlet pipe is connected and the end point of the tube to which the outlet pipe is connected are located on opposite sides of the heat exchanger, As a result, the bypass pipe connecting the water inlet pipe and the hot water outlet pipe must be arranged so as to cross the can body such as a heat exchanger, and the extension distance of the bypass pipe becomes relatively long.

  This invention is made | formed in view of such a situation, The place made into the objective is to provide the hot-water supply apparatus which can prevent especially the dew condensation generation | occurrence | production of a bypass pipe effectively.

  In order to achieve the above object, in the present invention, the heat exchanger is heated by passing through the heat exchanger heated by the combustion heat of the combustion burner, and the water intake pipe and the heat exchanger that allow water to flow through the heat exchanger. A hot water discharge pipe, a bypass pipe that connects the water intake pipe and the hot water discharge pipe so as to bypass the heat exchanger, a blower fan that supplies combustion air to the combustion burner, and the combustion burner The following specific matters are provided for a hot water supply device including an air supply passage portion that introduces combustion air heated by heat exchange with exhaust gas in an exhaust passage portion that discharges exhaust gas from the blower fan. It was decided. That is, at least a part of the bypass pipe is disposed so as to pass through a position in the vicinity of the air supply duct constituting the air supply passage portion.

  In the case of this invention, the outer surface of the bypass pipe receives heat radiation from the heated air inside through the wall of the air supply duct, and the outer surface of the bypass pipe is heated. For this reason, even if the cold water from the water intake pipe is caused to flow inside the bypass pipe, the occurrence of condensation on the outer surface thereof is prevented. In addition, the heat of the combustion air heated by heat exchange with the exhaust gas can be further used to prevent dew condensation on the bypass pipe, so that a large number of hairs can be planted on the outer surface of the bypass pipe. It is possible to prevent condensation without adding special processing such as.

  In the case of the present invention, the bypass pipe can be disposed so as to pass through a gap sandwiched between the air supply duct and the case of the combustion burner (claim 2). In this way, the gap between the supply air duct and the case of the combustion burner is both the preheated air in the supply air duct and the combustion gas in the case of the combustion burner during hot water supply operation (combustion operation). Since it is maintained at a relatively high temperature under the influence of heat from the heat generation, prevention of dew condensation is more effectively realized.

  As another invention, the heat exchanger heated by the combustion heat of the combustion burner, and the hot water heated by passing through the inlet pipe and the heat exchanger for passing water through the heat exchanger are discharged. A hot water outlet pipe, a bypass pipe that connects the water inlet pipe and the hot water outlet pipe so as to bypass the heat exchanger, a blower fan that supplies combustion air to the combustion burner, and exhaust gas from the combustion burner is discharged. The following specific matters are provided for a hot water supply apparatus including an air supply passage portion that supplies combustion air heated by heat exchange with exhaust gas in an exhaust passage portion to be supplied to the blower fan. Can do. That is, at least a part of the bypass pipe is disposed so as to pass through the wall of the air supply duct constituting the air supply passage and pass through the air supply duct.

  In the case of the present invention, the same effect as in the case of the first aspect of the invention can be obtained, and the bypass pipe is disposed so as to pass through the internal space through which the combustion air in the air supply duct flows. In the air supply duct, the bypass pipe is more directly subjected to heat radiation and heat conduction from the combustion air, thereby preventing condensation more reliably.

  Furthermore, in the above invention, the bypass pipe can be disposed at a position lower than the flange constituting the upper end opening edge of the case of the combustion burner. By doing in this way, even if dew condensation water generation | occurrence | production and the fall have arisen, the possibility that the unexpected trouble resulting from dew condensation water may occur can be avoided. That is, if condensed water falls on the flange of the above-mentioned combustion burner case, the condensed water drops in a diffused state where it is not known where the condensed water will spread around the flange and fall. It is possible to reliably avoid the occurrence of the occurrence of the occurrence of a situation where various electronic devices get wet with the dew condensation water.

  Further, a part of the exhaust passage part and a part of the air supply passage part can be configured as a double pipe type composed of an inner cylinder and an outer cylinder so that heat exchange with the exhaust gas can be performed. (Claim 5). By doing so, the combustion air is reliably heated by heat exchange with the exhaust gas in the exhaust passage, and as a result, the bypass pipe is heated by the combustion air in the air supply duct of the present invention to prevent condensation. The action can also be realized more reliably.

  As described above, according to the hot water supply apparatus of the present invention, the outer surface of the bypass pipe can be heated by the heat of the combustion air radiated through the wall of the air supply duct, Even when cold water from the water intake pipe flows, it is possible to reliably prevent the occurrence of condensation on the outer surface. In addition, the heat of the combustion air heated by heat exchange with the exhaust gas can be further used to prevent dew condensation on the bypass pipe, and thereby, a large number of hairs can be planted on the outer surface of the bypass pipe. It is possible to prevent condensation without adding special processing.

  In particular, according to the second aspect of the present invention, the bypass pipe is disposed so as to pass through a gap sandwiched between the air supply duct and the case of the combustion burner, whereby the combustion air in the air supply duct, the combustion burner, In the above gap, which is maintained at a relatively high temperature under the influence of both the combustion gas and the combustion gas in the case, prevention of condensation can be more effectively realized.

  According to the third aspect of the present invention, at least a part of the bypass pipe is disposed so as to pass through the wall of the air supply duct constituting the air supply passage and pass through the air supply duct. The bypass pipe receives heat radiation and heat conduction from the combustion air in the air duct more directly, thereby preventing condensation more reliably.

  According to claim 4, even if the dew condensation water is generated and dropped by arranging the bypass pipe at a position lower than the flange constituting the upper end opening edge of the case of the combustion burner. Thus, it is possible to reliably avoid the unexpected situation that the condensed water falls in the diffusion state, and to prevent the occurrence of the situation where various electronic devices get wet with the condensed water.

  Further, according to claim 5, a part of the exhaust passage part and a part of the air supply passage part are configured in a double pipe type composed of an inner cylinder and an outer cylinder, and heat exchange with the exhaust gas is performed. As a result, it is possible to more reliably realize that the combustion air is heated by exchanging heat with the exhaust gas in the exhaust passage portion, and thus the dew condensation is prevented by heating the bypass pipe with the combustion air of the present invention. The effect of achieving the above can be realized more reliably.

It is a schematic diagram which shows embodiment of the hot water supply apparatus of this invention. It is explanatory drawing which shows the hot water supply apparatus of a more concrete structure as what belongs to the said embodiment, the state which abbreviate | omitted the housing and was seen from the back side. FIG. 3 is a cross-sectional explanatory view taken along line AA in FIG. 2. FIG. 4A is a partially enlarged view of FIG. 3 showing a specific positional relationship between the bypass pipe and the air supply duct, FIG. 4A is an example of the proximity arrangement illustrated in FIG. 3, and FIG. 4B is an example of contact. FIG. 4C shows an example of internal penetration.

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

  FIG. 1 shows a basic hot water supply apparatus according to an embodiment of the present invention. In this hot water supply apparatus, the water entered from the water intake pipe 3 into the heat exchanger 2 is heat-exchanged and heated by the combustion heat of the combustion burner 4 while passing through the heat exchanger 2, and thereby heated to a predetermined temperature. Hot water is discharged through the tap pipe 5. The heat exchanger 2 shown in the figure is of a fin-and-tube type, and the water from the water intake pipe 3 is heated by heat exchange using a combustion gas, which will be described later, until a plurality of tubes are folded back to reach the hot water outlet pipe. It has become so. The combustion burner 4 is mixed and burned with combustion air from the blower fan 6 and gas as fuel supplied from the gas supply unit 7, and after the combustion gas has passed through the heat exchanger 2, The exhaust gas is discharged to the outside through the exhaust passage portion 8. Air is introduced into the blower fan 6 from the outside through an air supply passage portion 9, and a portion of the air supply passage portion 9 is adjacent to the exhaust passage portion 8. The air in the air supply passage 9 is heated by heat exchange with the exhaust gas in the portion 8.

  The combustion burner 4 is built in a burner case 10 whose upper end is open, the heat exchanger 2 is built in a heat exchanger case 11 that opens up and down, and the heat exchanger case 11 covers the upper end opening edge of the burner case 10. They are placed on the burner case flange 12 to be formed and coupled to each other. Further, an air supply / exhaust structure 13 is placed on the upper side of the heat exchanger case 11 and coupled to each other.

  The supply / exhaust structure unit 13 covers the upper side of the heat exchanger 2 and collects the exhaust gas after passing through the heat exchanger 2, and the exhaust gas collected in the exhaust gas collection unit 14 for a predetermined amount. The exhaust lead-out cylinder 15 is led out to the discharge place, the air supply introduction cylinder 16 constituting the outer cylinder surrounding the outer periphery with the exhaust lead-out cylinder 15 as an inner cylinder, and the exhaust collecting portion 14 are partitioned and formed. An air supply collecting portion 17 that collects air introduced from the air supply introducing cylinder 16 is provided. The exhaust lead-out cylinder 15 and the supply air introduction cylinder 16 are arranged in an inner / outer double pipe type, and the air in the supply air introduction cylinder 16 is heated to a predetermined temperature (by a heat of the exhaust gas in the inner exhaust lead-out cylinder 15). For example, heat exchange heating is performed up to 80 ° C. An air supply duct 18 is disposed so as to extend along the side portions of the heat exchanger case 11 and the burner case 10 from the air supply collecting portion 17 to the air blowing fan 6. Combustion air in a heated state is introduced from the portion 17. The exhaust passage portion 8 is constituted by the exhaust collecting portion 14 and the exhaust lead-out tube 15, and the air supply passage portion 9 is constituted by the air supply introducing tube 16, the air supply collecting portion 17 and the air supply duct 18.

  On the other hand, a water supply pipe (not shown) is connected to the upstream end of the water intake pipe 3, and water supplied at a predetermined water supply pressure from the water supply pipe is introduced into the heat exchanger 2. Further, the hot water outlet pipe 5 is connected to a hot water supply pipe (not shown) at the downstream end so that hot water can be supplied to a hot water tap such as a kitchen, a bathroom or a bath through the hot water supply pipe. The upstream end of the bypass pipe 19 is branched and connected to the water inlet pipe 3 in front of the heat exchanger 2, and the downstream end of the bypass pipe 19 is connected to join the intermediate position of the outlet pipe 5. That is, by the bypass pipe 19, the incoming water from the incoming water pipe 3 can be directly bypassed to the hot water outlet pipe 5 by bypassing the heat exchanger 2.

  The bypass pipe 19 branches from the water inlet pipe 3 and then is a gap 20 between the air supply duct 18 and the burner case 10 and passes through a position near the wall of the air supply duct 18 and is connected to the hot water pipe 5. It is arranged so that. That is, the outer surface of the bypass pipe 19 is heated by receiving heat radiation from the combustion air through the wall of the air supply duct 18, and thus, dew condensation occurs on the outer surface of the bypass pipe 19 through which cold water flows. Is to prevent the occurrence of. In addition, a gap 20 between the air supply duct 18 and the burner case 10, which is a space through which the bypass pipe 19 passes, is in a heated state in the air supply duct 18 during a hot water supply operation (combustion operation). Since the combustion air and the combustion gas in the burner case 10 are both affected by heat and maintained at a relatively high temperature, it is possible to more effectively prevent condensation. In addition, various electronic devices such as a motor for the blower fan 6, an electromagnetic valve for the gas supply system 7, and various sensors are not located at the lower position of the bypass pipe 19. On the other hand, the bypass pipe 19 is disposed so as to cross the position below the burner case flange 12. As a result, even if condensed water falls from the bypass pipe 19, it is prevented from falling on the various electronic devices, but if the condensed water falls on the burner case flange 12, the burner is prevented. It is possible to reliably avoid a situation in which the condensed water drops occur in a diffusion state in which it is not known where the condensed water will spread around the case flange 12 and fall.

  When the hot-water tap is opened and water of a predetermined flow rate or more enters from the water intake pipe 3 based on the water supply pressure, the blower fan 6 is activated, the combustion burner 4 is combusted, and the hot water heated to a predetermined temperature is heated. The hot water is discharged from the exchanger 2 to the hot water discharge pipe 5 and supplied to the hot water tap at the downstream end. In such a hot water supply operation, for example, by the operation of the blower fan 6 constituted by a sirocco fan, a turbo fan, or the like, external air is introduced from the supply air introduction cylinder 16 and gathered in the supply air collecting section 17, and then The air is introduced into the blower fan 6 through the air supply duct 18 and supplied to the combustion burner 4 as combustion air. Then, the exhaust gas generated by the combustion in the combustion burner 4 is discharged from the exhaust collecting portion 14 through the exhaust lead-out cylinder 15. As described above, the combustion air is heated in the supply / exhaust structure 13 by heat exchange between the combustion air supply and the exhaust gas exhaust, and the heat of the combustion air in the heated state is further increased. It can be used for preventing condensation of the bypass pipe 19. As described above, it is possible to prevent condensation by effectively using exhaust heat without adding special processing such as planting a large number of hairs to the outer surface of the bypass pipe 19.

  It should be noted that any of the following may be adopted as the position of the bypass pipe 19 in relation to the air supply duct 18 described above. That is, (1) the bypass pipe 19 is disposed so as to maintain a close contact state with the air supply duct 18 but (2) the bypass pipe 19 is fixed while being in contact with the air supply duct 18. Any one of (3) passing through the wall of the air supply duct 18 and arranging the bypass pipe 19 so as to pass through the inside of the air supply duct 18 can be adopted.

  Next, with reference to FIGS. 2 and 3, an example in which the hot water supply apparatus of FIG. In the following, the corresponding components will be described with the same reference numerals as those in FIG. 1, but each component of the water heater illustrated in FIGS. 2 and 3 embodies those of the water heater in FIG. 1 to the last. It is only an example. In both figures, the code | symbol 21 is a main body case of a hot-water supply apparatus, 22 is a front cover which shields the front opening part.

  The water supply / exhaust structure portion 13 of the hot water supply apparatus illustrated in FIGS. 2 and 3 is formed as follows. That is, the exhaust passage portion 8 is formed by the exhaust collecting portion 14 covering the upper end opening of the heat exchanger case 12 and the exhaust lead-out cylinder 15 extending upward from the exhaust collecting portion 14, while covering the exhaust collecting portion 14 from above. An air supply collecting portion 17 that extends upward from the air supply collecting portion 17 and covers the outer periphery of the exhaust lead-out tube 15, and the above-mentioned air supply. An air supply passage portion 9 is formed by an air supply duct 18 whose upstream end communicates with the collecting portion 17 through a communication hole 181 that extends laterally and whose downstream end communicates with the blower fan 6 through the communication hole 182. When viewed from the back side of the main body case 22 (see FIG. 2), the air supply duct 18 has an upstream end side (upper side) that expands to substantially the same width as the air supply assembly portion 17, and a downstream end side (lower side) that is a blower fan. 6 is formed as a duct having an inverted triangular shape that is tapered toward the communication hole 182 with respect to 6 and a flat shape (see FIG. 3).

  The fin-and-tube heat exchanger 2 is configured to have an odd number of tubes, so that the water intake pipe 3 is located on one side of the heat exchanger case 11 in the tube arrangement direction. At the position, the hot water discharge pipes 5 are respectively arranged at the left and right other positions of the heat exchanger case 11 and extend in the vertical direction. A bypass pipe 19 that connects the intermediate positions of the water inlet pipe 3 and the hot water outlet pipe 5 to each other is a gap 20 (see FIG. 3) between the air supply duct 18 and the burner case 10. It is arrange | positioned so that it may cross in the left-right direction in the position below the case flange 12. FIG.

  The specific positional relationship between this bypass pipe 19 and the air supply duct 18 is close to the wall 183 of the air supply duct 18 as shown in FIG. 4 or as shown in FIG. 4 (b) and fixed to each other in contact with the wall 183 of the air supply duct 18, or as shown in FIG. 4 (c). 183 may be disposed so as to pass through the internal space of the air supply duct 18.

  2 and 3 is the same as that described in the hot water supply apparatus of FIG. 1, but in the case of the hot water supply apparatus of FIGS. 2 and 3, a bypass for the air supply duct 18 is provided. Since the parallel running distance of the pipes 19 can be relatively long, a more effective one can be obtained from the viewpoint of preventing condensation.

<Other embodiments>
In addition, this invention is not limited to the said embodiment, Various other embodiments are included. That is, the shape of the air supply duct 18 is not limited as long as it can introduce combustion air to the blower fan 6. And depending on how this shape is selected, the bypass pipe is not only arranged so as to cross in the left-right direction, but may be configured to have a part that is bent in the middle and extends in the vertical direction, a part that skews, etc. Good. In addition to the double-pipe structure, the air supply / exhaust structure portion 13 is configured such that a part of the exhaust passage portion 8 and a portion of the air supply passage portion 9 are brought into contact with each other. It is also possible to adopt a structure in which combustion air is heated by receiving conduction.

2 Heat exchanger 3 Water inlet pipe 4 Combustion burner 5 Hot water outlet pipe 6 Blower fan 8 Exhaust passage section 9 Supply passage section 10 Burner case (combustion burner case)
12 Burner case flange (flange that forms the upper edge of the burner case)
13 Supply / exhaust structure part (part that is configured as a double-pipe type and performs heat exchange with exhaust gas)
18 Air supply duct 19 Bypass pipe 20 Clearance

Claims (5)

A heat exchanger that is heat-exchanged and heated by the combustion heat of the combustion burner, a water inlet pipe that allows water to flow through the heat exchanger, and a hot water outlet that is used to discharge hot water that has passed through the heat exchanger, and the heat exchanger A bypass pipe connecting the water intake pipe and the hot water discharge pipe to each other so as to bypass the gas generator, a blower fan for supplying combustion air to the combustion burner, and an exhaust gas in the exhaust passage section for discharging the exhaust gas from the combustion burner A hot water supply apparatus comprising a supply air passage section for introducing combustion air heated by heat exchange with the blower fan,
A hot water supply apparatus, wherein at least a part of the bypass pipe is disposed so as to pass a position in the vicinity of an air supply duct constituting the air supply passage section. The hot water supply device according to claim 1,
The hot water supply apparatus, wherein the bypass pipe is disposed so as to pass through a gap sandwiched between the air supply duct and the case of the combustion burner. A heat exchanger that is heat-exchanged and heated by the combustion heat of the combustion burner, a water inlet pipe that allows water to flow through the heat exchanger, and a hot water outlet that is used to discharge hot water that has passed through the heat exchanger, A bypass pipe connecting the water inlet pipe and the hot water outlet pipe to bypass the boiler, a blower fan for supplying combustion air to the combustion burner, and an exhaust gas in the exhaust passage section for discharging the exhaust gas of the combustion burner A hot water supply apparatus comprising a supply air passage section for supplying combustion air heated by heat exchange to the blower fan,
A hot water supply apparatus, wherein at least a part of the bypass pipe is disposed so as to pass through a wall of an air supply duct constituting the air supply passage section and pass through the air supply duct. The hot water supply device according to any one of claims 1 to 3,
The hot-water supply apparatus, wherein the bypass pipe is disposed at a position lower than a flange that constitutes an upper end opening edge of the case of the combustion burner. The hot water supply device according to any one of claims 1 to 4,
A hot water supply apparatus in which a part of the exhaust passage part and a part of the air supply passage part are configured in a double pipe type including an inner cylinder and an outer cylinder so that heat exchange with the exhaust gas is performed. .

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