JP6267431B2 - Latent heat recovery type heat source machine and neutralizer - Google Patents

Description

  The present invention relates to a latent heat recovery type heat source device that recovers sensible heat and latent heat from combustion exhaust and a drain neutralizer.

  Heat recovery efficiency is improved by providing a latent heat recovery heat exchanger that further recovers the latent heat of the exhaust downstream of the sensible heat recovery heat exchanger that mainly recovers sensible heat from the air heated by the burner (combustion exhaust). There is a heat source machine such as a latent heat recovery type water heater configured as described above.

  In such a latent heat recovery type heat source machine, water vapor contained in the exhaust gas condenses during the recovery of latent heat to generate condensed water (drain). This drain becomes acidic by absorbing nitrogen oxides and sulfur oxides in the exhaust gas. Therefore, in the latent heat recovery type heat source machine, drain is recovered, neutralized by a neutralizer, and then drained from a drain outlet.

  Usually, the neutralizer is configured by putting a neutralizer in a container having a water seal structure. In a state where drain is accumulated in the neutralizer and sealed with water, the exhaust does not leak out from the drain outlet through the neutralizer. However, since the neutralizer is in a dry state at the time of shipment from the factory, there is no drain inside and it is not sealed with water. Leaks out through the vessel. Exhaust leaked from the drain outlet not only causes discomfort to the people around you but also generates acidic drainage when condensed, so a heat source device is installed on the pipe shaft, etc., and piping and gas meters are nearby. And it will corrode them.

  Therefore, an operation in which an operator puts water into the neutralizer to ensure a water-sealed state before starting operation after installation is defined in the installation procedure.

  Patent Document 1 discloses a water heater that connects a water injection pipe branched from a water supply pipe to a neutralizer, and opens a solenoid valve provided in the middle of the water injection pipe so that water can be injected into the neutralizer. It is disclosed. This water heater is controlled so as to inhibit combustion until the water seal of the neutralizer is secured.

  In Patent Document 2 below, even if the water pipe passing through the latent heat recovery heat exchanger is corroded by the drain and the hole is opened, the water leaked from the hole is recovered in the drain pan and drained through the neutralizer. In order to solve the problem of not recognizing corrosion, a water heater provided with a water amount sensor for detecting the amount of water flowing through the drain pipe is disclosed in the middle of the drain pipe upstream of the neutralizer. Yes. This water amount sensor includes a reservoir space having a throttle at the bottom, a float that moves up and down in the reservoir space, and a sensor that detects the position of the float.

JP 2009-109085 A JP 2002-147847 A

  Even if the installation procedure stipulates that the operator put water into the neutralizer prior to the start of operation after installation, this work may not be performed due to the operator's mistakes or fatigue. On the other hand, when a water injection pipe or a solenoid valve is provided as disclosed in Patent Document 1, the manufacturing cost of the heat source device increases.

  In the water amount sensor disclosed in Patent Document 2, when the drain does not flow, the float is lowered and the throttle is covered. Therefore, in the state where the neutralizer is not sealed with water, the exhaust gas passes through the neutralizer and passes through the neutralizer. Plays a role in preventing leaks. However, there is a problem that when the dust or dirt accumulated in the drain pan flows into the drain pipe together with the drain, the throttle is immediately clogged.

  The present invention is intended to solve the above problem, and a latent heat recovery type heat source device and neutralization of drain capable of preventing exhaust from leaking outside through a drain discharge path before being sealed with water. The purpose is to provide a vessel.

  The gist of the present invention for achieving the object lies in the inventions of the following items.

[1] a combustion part;
A heat exchanger that recovers sensible heat and latent heat from the exhaust of the combustion section;
A drain recovery section for recovering drain generated in the heat exchanger;
A drain discharge path for discharging the drain recovered by the drain recovery unit to the outside;
A water seal provided in the middle of the drain discharge path;
A water storage part provided in the middle of the drain discharge path and downstream of the water seal part,
Before the water sealing is completed and the drain overflowing from the water sealing part is collected in the water storage part, the outlet of the water storage part is blocked, and the sealing is released by a water pressure higher than a predetermined value by the drain accumulated in the water storage part. A blockade to perform,
The space between the water surface at the highest water level on the rear chamber side of the water seal portion and the water surface at the highest water level that can be stored in the water storage portion is the upstream side of the water surface at the highest water level of the front chamber of the water seal portion. A communication part communicating with the drain discharge path;
A latent heat recovery type heat source machine characterized by comprising:

  In the above-described invention and the invention described in [5] below, even if the operation of the heat source unit is started after installation without installing the water seal portion, the outlet of the water storage portion provided downstream of the water seal portion Since the sealing part is blocking, exhaust is prevented from flowing out through the drain discharge path. In addition, after the water sealing is completed, when drain overflowing from the water sealing part is stored in the water storage part, the sealing by the sealing part 30 is automatically released by the water pressure, so that drain drainage through the drain discharge passage is secured. The

[2] The latent heat recovery type heat source device according to [1], wherein the water seal portion functions as a neutralizer in which a neutralizer is inserted to neutralize the drain.

  In the above invention and the invention described in [5] below, the water seal portion also functions as a neutralizer.

[3] The predetermined value is larger than a pressure obtained by adding an indoor negative pressure to a maximum value of the exhaust pressure in the combustion section, and less than a water head pressure at the maximum water level in the water storage section. The latent heat recovery type heat source machine according to [1] or [2].

  In the above invention and the invention described in [6] below, the sealed state is maintained even when negative pressure is applied to the exhaust pressure due to opening / closing of an indoor door, etc., and the blockage is released before the water storage part becomes full. Is done.

[4] The latent heat recovery type heat source device according to any one of [1] to [3], wherein the blocking portion is an on-off valve that is urged to be closed and can be repeatedly opened and closed. .

  In the above-mentioned invention and the invention described in [7] below, since the blocking portion is repeatedly opened and closed, the exhaust gas leaks from the drain discharge passage in the first operation after installation, and after draining for freezing prevention. Even in operation, exhaust gas leakage from the drain discharge path can be prevented.

[5] A combustion part, a heat exchanger that recovers sensible heat and latent heat from the exhaust gas of the combustion part, a drain recovery part that recovers drain generated in the heat exchanger, and a drain recovered by the drain recovery part A neutralizer that is interposed in the drain discharge path of the latent heat recovery type heat source device including a drain discharge path that discharges to the outside,
A water seal portion into which a neutralizing agent is placed;
A water storage part for storing drainage overflowing from the water seal part;
Before the water sealing is completed and the drain overflowing from the water sealing part is collected in the water storage part, the outlet of the water storage part is blocked, and the sealing is released by a water pressure higher than a predetermined value by the drain accumulated in the water storage part. A blockade to perform,
The space between the water surface at the highest water level on the rear chamber side of the water seal portion and the water surface at the highest water level that can be stored in the water storage portion is the upstream side of the water surface at the highest water level of the front chamber of the water seal portion. A communication part communicating with the drain discharge path;
The neutralizer characterized by having.

[6] The predetermined value is larger than a pressure obtained by adding an indoor negative pressure to a maximum value of the exhaust pressure in the combustion section, and less than a water head pressure at the maximum water level in the water storage section. 5].

[7] The neutralizer according to [5] or [6], wherein the blocking portion is an on-off valve that is urged to be closed and can be repeatedly opened and closed.

  According to the latent heat recovery type heat source device and neutralizer according to the present invention, it is possible to prevent the exhaust from leaking to the outside through the drain discharge passage before being sealed with water, and the sealing is automatically performed after the water sealing is completed. It is released and drainage is secured.

It is a figure showing the composition of the outline of the heat source machine concerning an embodiment of the invention. It is a figure which shows the structure of a neutralizer. It is a figure which shows the state change of the neutralizer at the time of installing the heat-source equipment shipped from the factory and operating for the first time. It is a figure which shows the example of the neutralizer which provided the pore for ventilation | gas_flowing in the upper part of the container of the back chamber side of a water seal part. It is a figure which shows the example of the neutralizer which provided the pore for ventilation | gas_flowing which connects a front chamber and a back chamber in the partition plate of a water seal part.

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

  FIG. 1 shows a schematic configuration of a heat source device 3 according to an embodiment of the present invention. The heat source unit 3 has a hot water supply function of heating the supplied water and discharging it. The heat source unit 3 mainly generates sensible heat from a burner 4 that burns combustion gas, a combustion fan 5 that sends air to the burner 4, and air (combustion exhaust) that is installed above the burner 4 and heated by the burner 4. A sensible heat exchanger 6 that collects and heats the feed water, and a latent heat heat exchanger that is arranged downstream of the sensible heat exchanger 6 by the air flow from the burner 4 and mainly collects the latent heat of the exhaust to heat the feed water. A container 7 is provided.

  The heat source unit 3 further includes a combustion chamber 8 in which the burner 4, the sensible heat exchanger 6, and the latent heat exchanger 7 are arranged in this order from the bottom, and an exhaust pipe 9 communicating with the upper end of the combustion chamber 8. Is provided.

  Below the latent heat exchanger 7, a tray 11 is provided for receiving and collecting acidic condensed water (drain) generated by collecting the latent heat of the exhaust. A drain recovery port 12 is provided at the bottom near the outlet of the exhaust tube 9. The drain recovered by the drain recovery unit (the tray 11 and the drain recovery port 12) is drained through the drain discharge pipe 13. A neutralizer 20 having a water sealing function and a function of neutralizing the drain is provided in the middle of the drain discharge pipe 13. The outlet 28 of the neutralizer 20 is provided with a sealing portion 30 that seals the outlet 28 and releases the sealing with a predetermined or higher water pressure. In addition, at the time of factory shipment, the inside of the neutralizer 20 is in a dry state without drain.

  FIG. 2 shows the configuration of the neutralizer 20 in more detail. The neutralizer 20 includes a water seal portion 21 (gray portion in FIG. 2) that performs a water seal function, and a water storage portion 23 that communicates with the outlet 22 of the water seal portion 21. The water seal portion 21 has a structure in which a hollow container is divided into two chambers (a front chamber 25 and a rear chamber 26) by a partition plate 24 so that the lower portion communicates therewith.

  A drain inlet 27 that receives drain from a drain discharge pipe 13 a upstream of the neutralizer 20 is provided in the upper portion of the front chamber 25. The drain inlet 27 is connected to the end of the drain discharge pipe 13a. In the upper part of the rear chamber 26, the aforementioned outlet 22 for discharging the neutralized drain is provided. The water storage portion 23 communicating with the outlet 22 is a hollow cylindrical vertically long container extending downward from the outlet 22 along the water seal portion 21 by a predetermined length, and an outlet 28 is formed at the lower end thereof. Is provided. The outlet 28 is connected to the entrance side of the above-described blocking portion 30, and the outlet side of the blocking portion 30 is connected to the start end of the drain discharge pipe 13 b on the downstream side of the neutralizer 20.

  The blocking unit 30 is configured to block the outlet 28 of the water storage unit 23 and to release the blocking when a water pressure equal to or higher than a predetermined value (valve opening pressure) is applied from the outlet 28 side. 2 includes a valve body 31 that seals the outlet 28 and a spring 32 as an elastic body that biases the valve body 31 so as to press the outlet 31 against the outlet 28.

  The valve body 31 is a flat plate member whose surface that contacts the outlet 28 is formed of an elastic body such as rubber. One end of the valve body 31 is pivotally supported on the side of the outlet 28, and a closed position in which a flat portion is brought into contact with the outlet 28 to seal the outlet 28, and approximately 90 downward from the closed position. It is displaced to the open position that has been rotated. The spring 32 is configured by a torsion spring or the like provided coaxially with the shaft that supports the valve body 31, and biases the valve body 31 toward the closed position.

  The valve opening pressure of the valve body 31 of the blocking part 30 is larger than the pressure obtained by adding the indoor negative pressure to the maximum value of the exhaust pressure reaching the sealing part 30 from the burner 4 via the drain discharge pipe 13 and the like, and It is made less than the water head pressure at the maximum water level of the water reservoir 23.

For example, the lower limit of the valve opening pressure of the valve body 31 of the blocking portion 30 is the maximum value of exhaust pressure reaching the blocking portion 30 (about 20 mmH ₂ O), which is a negative pressure caused by opening and closing the door, taking into account the approximately -20MmH ₂ O and is assumed) is set to ₂ O about 20～50MmH (preferably 40MmH ₂ O or more obtained by adding the room negative pressure). Further, the upper limit of the valve opening pressure is set to a value lower than the water head pressure at the maximum water level of the water reservoir 23. For example, when the water head pressure at the maximum water level of the water storage unit 23 is 120 mmH ₂ O, the upper limit of the valve opening pressure is set to about 100 mmH ₂ O with a certain margin.

  The outlet 22 of the water seal portion 21 is set at a position lower than the drain inlet 27. Moreover, the water storage part 23 is made lower than the outflow port 22 of the water sealing part 21, and the drop from the outflow port 22 to the outlet 28 at the lower end of the water storage part 23 gives a water head pressure larger than the valve opening pressure of the sealing part 30. To be set.

  The front chamber 25 and the rear chamber 26 of the water seal portion 21 are loaded with a neutralizing agent 29 for neutralizing condensed water (drain). The neutralizing agent 29 is calcium carbonate or the like, and has a bean-sized size of about 1 cm in diameter. The drain that has flowed in from the drain inlet 27 is neutralized when passing through the gaps between a number of granular neutralizing agents 29 loaded in the front chamber 25 and the rear chamber 26 of the water seal portion 21.

  Next, the effect | action of the blocking part 30 is demonstrated.

  FIG. 3 shows changes in the state of the neutralizer 20 and the blocking unit 30 when the heat source device 3 shipped from the factory is installed and operated for the first time.

  At the time of shipment from the factory, as shown in FIG. 3A, the inside of the neutralizer 20 is in a state where the drain is empty and dried. When the operation is started in this state, a part of the exhaust gas tries to flow into the neutralizer 20 side through the drain discharge pipe 13a. However, since the outlet of the neutralizer 20 is blocked by the blocking portion 30, Almost no exhaust gas is also prevented from flowing out through the drain discharge pipe 13b. If the block 30 is not sealed, a part of the exhaust gas flows out to the outside through the drain discharge pipe 13 and causes a problem as described in the background art section. The broken line in FIG. 3A indicates the flow of exhaust when the blocking portion 30 is not provided.

  When the operation of the heat source device 3 is continued, the drain begins to accumulate in the water seal portion 21 of the neutralizer 20. And as shown in FIG.3 (b), when the water level in the water seal part 21 of the neutralizer 20 rises and the water seal part 21 is in a state sealed with drainage, the water seal is thereafter used. Exhaust gas is prevented from flowing out through the drain discharge pipe 13.

  Thereafter, when the operation is further continued and the drain continues to flow into the neutralizer 20, as shown in FIG. 3C, the drain overflows from the outlet 22 of the water seal portion 21 and flows out to the water storage portion 23, and the water storage portion 23 is stored. When the operation is further continued, when the water level in the water storage section 23 rises and the water head pressure exceeds the valve opening pressure of the valve body 31 of the blocking section 30, the valve body 31 is opened as shown in FIG. And the blocking of the outlet 28 by the blocking portion 30 is released. Thereby, the drain stored in the water storage unit 23 is discharged to the outside through the drain discharge pipe 13b.

  When the drain accumulated in the water storage section 23 is discharged, the valve body 31 is urged by the spring 32 and returns to the closed position again to block the outlet 28. Thereafter, when the water level in the water storage section 23 rises and the water head pressure exceeds the valve opening pressure of the valve body 31, the valve body 31 opens, drainage stored in the water storage section 23 is discharged, and drainage is discharged. The operation of closing the valve body 31 is repeated.

  As described above, even if the operation of the heat source unit 3 is started after the factory is shipped and the neutralizer 20 is not sealed with water, the exhaust is drained by the blockade at the block 30. Through the outside is prevented. Further, when the water pressure of the drain overflowing from the neutralizer 20 after completion of water sealing and stored in the water storage part 23 exceeds the valve opening pressure, the valve body 31 of the sealing part 30 is opened and the sealing is automatically released. Drain drainage through the discharge pipe 13 is ensured.

  Therefore, the operation | work which an operator puts water into a neutralizer and ensures a water seal state before the operation | movement start after installation becomes unnecessary. In addition, when the operator manually puts water, a water level sensor should be installed in the neutralizer to take measures such as prohibiting operation before the completion of water sealing and warning that water has been forgotten. However, in the heat source device 3 according to the present embodiment, such a countermeasure is not required at all by attaching the blocking portion 30. Or the structure which connects the water injection piping branched from the water supply pipe to the neutralizer, and automatically injects water to the neutralizer by opening the electromagnetic valve provided in the middle of the water injection piping becomes unnecessary.

  When the drain level in the water seal 21 rises from the state shown in FIG. 3B (when the water seal is completed) to the state shown in FIG. 3C, the drain on the outlet side (rear chamber 26 side) The volume of the space from the water surface to the blocking part 30 (or the water surface of the drain stored in the water storage part 23) gradually decreases and the internal pressure increases. If the internal pressure rises excessively, the water level will no longer rise.

  Therefore, a slight air permeability is ensured in the container of the portion forming the space from the water surface at the highest water level on the rear chamber 26 side of the water seal portion 21 to the water surface at the highest water level that can be stored in the water storage portion 23. So that it is not completely airtight. For example, a gap is provided so that the container in the above portion does not become airtight, or pores for ventilation are provided. In addition, if ventilation pores or gaps are provided at a location lower than the water surface at the highest water level on the rear chamber 26 side of the water seal portion 21 or a location lower than the water surface at the highest water level of the water storage portion 23, drainage is generated from that portion. If it leaks out or the water level becomes higher than the ventilation pores, the air cannot escape.

  FIG. 4 shows an example in which vent holes 44 are provided in the upper part of the container on the rear chamber 26 side of the water seal portion 21. The ventilation pores 44 are opened in the main body of the heat source unit 3. During the operation of the heat source unit 3 before completion of water sealing, the exhaust gas leaks to the outside through the ventilation pores 44, though very little. Therefore, when the ventilation pores 44 are provided at positions as shown in FIG. 4, it is desirable that the heat source device 3 is an outdoor installation type. Further, since the ventilation pores 44 are opened in the main body of the heat source unit 3, for example, even when the heat source unit 3 is provided on the pipe shaft, the exhaust gas from the ventilation pores 44 directly flows into the pipe shaft. Therefore, gas pipes in the pipe shaft are not corroded.

  On the other hand, when the heat source device 3 is of an indoor installation type, it is desirable that even a slight amount of exhaust gas does not leak into the room through the ventilation pores 44. Therefore, the ventilation pores 44 are opened to the exhaust path of the heat source unit 3. For example, as shown in FIG. 5, when vent holes 45 for communicating the front chamber 25 and the rear chamber 26 are formed in the partition plate 24 at a position higher than the maximum water level, the outlet of the exhaust gas through the vent holes 45 is formed. It will be opened to the exhaust path. In this configuration, the exhaust gas does not leak to the outside during the operation of the heat source unit 3 before completion of water sealing. Further, after the water sealing is completed, when the water level in the neutralizer 20 rises, the air in the rear chamber 26 moves to the front chamber 25 side through the ventilation pores 45, and passes through the drain discharge pipe 13 a and the exhaust tube 9. It is discharged outside.

  Instead of providing the ventilation pore 45 in the partition plate 24, for example, the ventilation pore 44 of FIG. 4 is provided, and the outlet of the ventilation pore 44 is connected to the drain inlet 27 or the drain discharge pipe 13a with a pipe or the like. You may make it communicate.

  As described above, in the heat source device 3 according to the present embodiment, the outlet 30 is closed at the outlet of the water reservoir 23 provided downstream of the water seal 21 and the seal 30 is released with water pressure equal to or higher than a predetermined value. Therefore, the exhaust gas is prevented from leaking outside through the drain discharge pipe 13 in the operation before the water seal portion 21 is sealed with water. Further, after completion of the water sealing, if the drain overflowing from the water sealing part 21 is stored in the water storage part 23 more than a certain amount, the sealing of the sealing part 30 is automatically released by the water pressure, so the drain overflowing from the neutralizer 20 Can be smoothly discharged through the drain discharge pipe 13b.

  The embodiment of the present invention has been described with reference to the drawings. However, the specific configuration is not limited to that shown in the embodiment, and there are changes and additions within the scope of the present invention. Are also included in the present invention.

  The block 30 shown in the embodiment is an example, and other configurations may be used as long as the outlet 28 of the water storage unit 23 is blocked and the function of releasing the block with a water pressure equal to or higher than a predetermined value is achieved. For example, in the embodiment, the blocking portion 30 is an on-off valve that can be repeatedly opened and closed. However, once the blocking is released, a configuration that does not return to the blocking state again may be used. For example, when a predetermined or higher water pressure is applied, a part of the blocking part 30 may be broken and broken to be released and the blocking may be released.

  In consideration of freezing for freezing prevention, it is preferable that the blocking portion 30 is configured to be able to be repeatedly opened and closed. That is, when the drain in the neutralizer 20 is discharged to prevent freezing, the water seal portion 21 of the neutralizer 20 is not sealed in the same manner as at the time of factory shipment. In order to prevent the exhaust from leaking from the drain discharge pipe 13 during operation, it is preferable that the blocking portion 30 returns to the blocking state again after draining.

  In the embodiment, the neutralizing agent 29 is added to the water sealing portion 21 so that the water sealing portion 21 is also used as the neutralizer 20. However, a neutralizer and a water sealing portion for neutralizing the drain are provided separately. It doesn't matter.

  In the embodiment, the neutralizer 20 in which the water sealing part 21 and the water storage part 23 are integrated is illustrated. However, if the water sealing part 21 is downstream of the water sealing part 21, the water storage part 23 is located some distance away from the water sealing part 21. May be provided. In addition, the water storage part 23 is provided so that it may be located below the outflow port 22 of the water seal part 21.

  The present invention may be configured as a neutralizer including the water sealing part 21, the water storage part 23, and the sealing part 30 attached to the outlet 28 of the water storage part 23.

  The heat source unit 3 is not limited to a water heater, and may be a heater or a dryer.

DESCRIPTION OF SYMBOLS 3 ... Heat source machine 4 ... Burner 5 ... Fan 6 ... Sensible heat exchanger 7 ... Latent heat exchanger 8 ... Combustion chamber 9 ... Exhaust tube 11 ... Sauce tray 12 ... Drain collection port 13, 13a, 13b ... Drain discharge pipe 20 ... Neutralizer 21 ... Water sealing part 22 ... Outlet 23 ... Water storage part 24 ... Partition plate 25 ... Front chamber 26 ... Rear chamber 27 ... Drain inlet 28 ... Outlet 29 ... Neutralizing agent 30 ... Sealing part 31 ... Valve 32 ... Spring 44 ... Ventilation pore 45 ... Ventilation pore

Claims (7)

A combustion section;
A heat exchanger that recovers sensible heat and latent heat from the exhaust of the combustion section;
A drain recovery section for recovering drain generated in the heat exchanger;
A drain discharge path for discharging the drain recovered by the drain recovery unit to the outside;
A water seal provided in the middle of the drain discharge path;
A water storage part provided in the middle of the drain discharge path and downstream of the water seal part,
Before the water sealing is completed and the drain overflowing from the water sealing part is collected in the water storage part, the outlet of the water storage part is blocked, and the sealing is released by a water pressure higher than a predetermined value by the drain accumulated in the water storage part. A blockade to perform,
The space between the water surface at the highest water level on the rear chamber side of the water seal portion and the water surface at the highest water level that can be stored in the water storage portion is the upstream side of the water surface at the highest water level of the front chamber of the water seal portion. A communication part communicating with the drain discharge path;
A latent heat recovery type heat source machine characterized by comprising: The latent heat recovery type heat source device according to claim 1, wherein the water seal portion functions as a neutralizer in which a neutralizer is placed to neutralize the drain. The predetermined value is greater than a pressure obtained by adding an indoor negative pressure to a maximum value of an exhaust pressure in the combustion section, and less than a water head pressure at a maximum water level in the water storage section. The latent heat recovery type heat source machine according to 2. The latent heat recovery type heat source device according to any one of claims 1 to 3, wherein the blocking portion is an on-off valve that is urged to close and can be repeatedly opened and closed. A combustion unit, a heat exchanger that recovers sensible heat and latent heat from the exhaust of the combustion unit, a drain recovery unit that recovers drain generated in the heat exchanger, and the drain recovered by the drain recovery unit to the outside A neutralizer installed in the drain discharge path of a latent heat recovery type heat source device including a drain discharge path for discharging,
A water seal portion into which a neutralizing agent is placed;
A water storage part for storing drainage overflowing from the water seal part;
Before the water sealing is completed and the drain overflowing from the water sealing part is collected in the water storage part, the outlet of the water storage part is blocked, and the sealing is released by a water pressure higher than a predetermined value by the drain accumulated in the water storage part. A blockade to perform,
The space between the water surface at the highest water level on the rear chamber side of the water seal portion and the water surface at the highest water level that can be stored in the water storage portion is the upstream side of the water surface at the highest water level of the front chamber of the water seal portion. A communication part communicating with the drain discharge path;
The neutralizer characterized by having. The predetermined value is larger than a pressure obtained by adding an indoor negative pressure to a maximum value of an exhaust pressure in the combustion section and less than a water head pressure at a maximum water level in the water storage section. The neutralizer described. The neutralizer according to claim 5 or 6, wherein the blocking portion is an on-off valve that is urged to close and can be repeatedly opened and closed.