Latent heat recovery type water heater

Abstract

To provide a latent heat recovery type water heater capable of reliably performing water seal of a water-sealing part.SOLUTION: A water heater which neutralizes such drain water generated by combustion exhaust gas getting to dew point or lower by means of a neutralizer 37 includes drain exhaust piping 40 communicated with the neutralizer 37. The drain exhaust piping 40 has a first piping part 41, a pump 42, a rising part 43 and an auxiliary part 44, and further includes a water seal part 46 which performs water seal on the upstream side of the pump 42, or performs water-sealing on the upstream side and the downstream side of the pump 42, water seal detection means 45 which performs water seal detection of the water seal part 46, and a control part 60. When such a water level that the water seal detection means 45 detects water-seal is set as a first water level, the sum of volumes of the lower side than the first water level among internal volume of the neutralizer 37, the first piping part 41 and the pump 42 is set as V1, and an internal volume of a portion higher than the first water level on the downstream side of the pump 42 and lower than the height of an upper end 43a of the rising part 43 is set as V2, the relation of V1≤V2 is obtained.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a latent heat recovery water heater equipped with a neutralizer for neutralizing drain water, and more particularly to a floor-standing type latent heat recovery water heater for indoor installation. [Background technology]

[0002] Conventionally, this type of latent heat recovery water heater has included a burner unit, a heat exchange unit in which drain water is produced when the combustion exhaust gas generated by combustion in the burner unit is cooled below its dew point through heat exchange with a heated fluid, a neutralizer that neutralizes the drain water produced in the heat exchange unit, a piping unit connected to an outlet for discharging drain from the neutralizer, an on-off valve that opens and closes the piping unit, and a water level detection sensor that detects the level of the drain water, and when it is determined based on a detection signal from the water level detection sensor that the drain water has accumulated at or above a predetermined level, the on-off valve is opened to discharge the drain water (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6483537 Summary of the Invention [Problem to be solved by the invention]

[0004] In such latent heat recovery water heaters, drain water generated in the heat exchanger is stored in the neutralizer, and the neutralizer is often disposed below the appliance. Furthermore, among latent heat recovery water heaters, floor-standing models for indoor installation have a problem in that when trying to drain the neutralized drain water from the neutralizer at the bottom of the appliance, there is little difference in height between the neutralizer located at the bottom of the appliance and the drain outlet installed on the indoor floor, which limits the flexibility of installation.

[0005] Therefore, the inventors thought that the flexibility of drainage construction could be increased by pumping the drain water from the neutralizer located at the bottom of the appliance up to the top of the appliance and then discharging it outside the appliance (draining it up).

[0006] On the other hand, when installing indoors, it was necessary to ensure that the drainage path was sealed with drain water to prevent combustion exhaust gas from leaking out of the drainage path. In particular, when draining water with a pump, it was necessary to leave an appropriate amount of drain water for the water seal to prevent excessive drainage and breaking the water seal, which required further consideration.

[0007] The present invention has been made in consideration of this background, and aims to provide a latent heat recovery water heater that increases the freedom of installation and ensures reliable water sealing of the water seal section without introducing a complex configuration. [Means for solving the problem]

[0008] The present invention has been made to achieve the above object, and in claim 1, there is provided a device for neutralizing drain water generated when combustion exhaust gas after combustion in a burner section drops below the dew point by passing the drain water through a neutralizer pre-filled with a neutralizing agent, the device comprising: a drain discharge pipe downstream of the neutralizer in communication with the neutralizer; the neutralizer having a neutralizer inlet into which the drain water flows, a neutralizer outlet from which the drain water after neutralization is discharged, and full water detection means for detecting whether the neutralizer is full of water; the drain discharge pipe having a first piping section in communication with the neutralizer outlet, a pump in communication with the downstream end of the first piping section for discharging the drain water from the neutralizer outside the appliance, an ascending section in communication with the downstream end of the pump, and an auxiliary section in communication with the upper end of the ascending section; the auxiliary section having a drain outlet at its downstream end and a full water detection means for detecting whether the neutralizer is full of water; The pump further comprises an atmosphere communication section that communicates the drain water in the auxiliary section with the atmosphere, a water seal section that seals the water upstream of the pump or seals the water upstream and downstream of the pump, a water seal detection means that detects whether the water level is higher than the water level when the water seal section is water sealed, and a control section that controls the burner section and the pump, and the pump is configured to allow drain water to flow between the upstream and downstream sides of the pump when the pump is off, and the water level at which the water seal detection means detects that the pump is water sealed is defined as a first water level, and the sum of the internal volumes of the neutralizer, the first piping section, and the pump that are below the first water level is defined as V1, and the internal volume of the part downstream of the pump that is higher than the first water level and lower than the height of the upper end of the rising section is defined as V2, where V1 is equal to or less than V2.

[0009] In claim 2, the control unit is characterized in that when the full water detection means detects full water, it drives the pump on to discharge the drain water from the neutralizer outside the appliance, and turns it off after a first time has elapsed since the pump was turned on.

[0010] In claim 3, the water seal detection means is provided upstream of the pump, and when the full water detection means detects full water, the control unit drives the pump on to discharge the drain water from the neutralizer outside the appliance, and when the water seal detection means does not detect a water seal, the control unit drives the pump off. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a latent heat recovery water heater that allows greater freedom in the drain water discharge method and ensures water sealing of the drain discharge piping. [Brief explanation of the drawings]

[0012] [Figure 1] Schematic configuration diagram of a first embodiment of the present invention [Figure 2] Block diagram of a first embodiment of the present invention [Figure 3] Piping diagram of the first embodiment of the present invention [Figure 4] An explanatory diagram of a drainage process according to the first embodiment of the present invention. [Figure 5] Flowchart diagram of the first embodiment of the present invention [Figure 6] Schematic configuration diagram of a second embodiment of the present invention [Figure 7] An explanatory diagram of a drainage step according to a second embodiment of the present invention. [Figure 8] Flowchart diagram of the second embodiment of the present invention [Figure 9] Schematic configuration diagram of a third embodiment of the present invention [Figure 10] An explanatory diagram of a drainage step according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] A first embodiment of the present invention will be described with reference to FIGS.

[0014] Reference numeral 1 denotes a latent heat recovery type hot water heater of the first embodiment, which is a hot water heater equipped with a burner unit 8 that forms a downward flame. 5 is a housing of the latent heat recovery type water heater 1.

[0015] Burner section 8 burns fuel such as petroleum, and reference numeral 9 denotes a fuel pump that pressure-feeds fuel to burner section 8 via an oil supply pipe 10. Primary air and secondary air for combustion in burner section 8 are supplied by a combustion fan 13.

[0016] A primary heat exchanger 25 is arranged downstream of the combustion exhaust gas from the burner section 8, and a secondary heat exchanger 27 is arranged downstream of the primary heat exchanger 25. The combustion exhaust gas that passes through the primary heat exchanger 25 and then the secondary heat exchanger 27 is exhausted outside the latent heat recovery water heater 1 via the combustion exhaust path 35 and the exhaust outlet 49. The dashed arrows in Figure 1 indicate the flow of combustion exhaust gas.

[0017] The primary heat exchanger 25 is a sensible heat exchanger arranged downstream of the combustion chamber 19, and is configured as a fin tube type that recovers sensible heat from the combustion exhaust gas generated by combustion in the burner section 8 and heats the heated fluid flowing through the primary heat receiving pipe 24.

[0018] The secondary heat exchanger 27 recovers latent heat from the combustion exhaust gas after passing through the primary heat exchanger 25 and heats the fluid to be heated that flows through the heat receiving pipe 26 . Below the secondary heat exchanger 27, an inclined bottom plate 29 is provided to guide the drain water that has formed on the surface of the heat receiving pipe 26 and dripped down. This bottom plate 29 guides the drain water to a branching portion 31 provided below the secondary heat exchanger 27, and then to a condensation water flow path 32.

[0019] The drain water guided by the bottom plate 29 is neutralized through the condensed water flow path 32 in a neutralizer 37 that communicates with the condensed water flow path 32 and contains a neutralizing agent whose main component is calcium carbonate.

[0020] The neutralizer 37 has a neutralizer inlet 37a through which drain water flows in, a neutralizer outlet 37b through which drain water after neutralization is discharged, and a full water detection means 38 equipped with a pair of water level detection electrodes 38a for detecting whether the neutralizer 37 is full of water. A drain discharge pipe 40 communicating with the neutralizer 37 is provided downstream of the neutralizer 37.

[0021] The drain discharge piping 40 has a first piping section 41 that communicates with the neutralizer outlet 37b, a pump 42 that communicates with the downstream end of this first piping section 41 and discharges the drain water of the neutralizer 37 outside the appliance, an ascending section 43 that communicates with the downstream end of this pump 42, and an auxiliary section 44 that communicates with the upper end 43a of this ascending section 43. The rising portion 43 allows drain water in the neutralizer 37 provided below the housing 5 to flow upward in the housing 5 when the drain water is discharged. The auxiliary portion 44 has a drain outlet 44a at its downstream end for discharging drain water, and an atmosphere communication portion 44b for communicating the drain water in the auxiliary portion 44 with the atmosphere. The pump 42 is configured so that drain water can flow between the upstream side and downstream side of the pump 42 when the pump 42 is turned off.

[0022] Also, a water sealing section 46 is provided to seal the upstream and downstream sides of the pump 42 with water. The water sealing section 46 uses a part or all of the neutralizer 37, the first piping section 41, the pump 42 and the rising section 43, which are all connected together to form a U-shaped pipe to perform water sealing. In addition, the rising section 43, which is downstream of the pump 42, is provided with a water seal detection means 45 having a pair of water level detection electrodes 45a for detecting whether the water level is higher than the water level when the water seal section 46 is water sealed. This water seal detection means 45 may be provided in the neutralizer 37 or the first piping section 41 on the upstream side of the pump 42 .

[0023] The shaded areas in Figure 1 indicate the range of the internal volume of each part. In the present invention, the water level at which the water seal detection means 45 detects that a water seal is present is defined as the first water level, the sum of the internal volumes of the neutralizer 37, the first piping section 41, and the pump 42 below the first water level is defined as V1, and the internal volume of the portion downstream of the pump 42 that is higher than the first water level and lower than the height of the upper end 43a of the rising section 43 is defined as V2, and the configuration is such that V1≦V2. Here, more specifically, the sum of volumes V1 is V11, where V11 is the internal volume of the neutralizer 37 below the first water level, V12 is the internal volume of the first piping section 41 below the first water level, and V13 is the sum of the internal volumes of the pump 42 below the first water level, so that V1 = V11 + V12 + V13.

[0024] Reference numeral 60 denotes a control section that controls the burner section 8 and the pump 42 . This control unit 60 is configured to turn on the pump 42 to discharge the drain water from the neutralizer 37 outside the appliance when the full water detection means 38 detects full water, and to turn off the pump 42 after a first time has elapsed (e.g., 10 seconds) since the pump 42 was turned on.

[0025] Drain outlet 44a is connected to the inlet of drain pipe 80. The outlet of drain pipe 80 is installed so as to communicate with a tee pipe 85 which communicates with a drain pipe 82 of a domestic washing machine 81 and an elbow pipe 84 connected to a drain trap 83, for example.

[0026] Next, the operation will be described.

[0027] When a hot water tap (not shown) connected to hot water pipe 22 is opened and flow sensor 23 detects the flow of the heated fluid, control unit 60 causes a spark plug (not shown) to discharge and fuel pump 9 to drive, thereby igniting fuel in burner unit 8, and combustion begins by driving combustion fan 13. When combustion begins, a combustion flame is formed in burner unit 8 while maintaining an appropriate air-fuel ratio, using fuel pump 9 and an oil proportional valve (not shown) or the like to supply the necessary amount of atomized oil according to the required heat amount, and combustion fan 13.

[0028] The combustion exhaust gas generated by combustion heats the primary heat receiving pipe 24 of the primary heat exchanger 25, and heats the fluid to be heated flowing through the primary heat receiving pipe 24. Furthermore, after passing through the primary heat exchanger 25, the combustion exhaust gas recovers latent heat from the combustion exhaust gas and heats the fluid to be heated flowing through the heat receiving pipe 26. The combustion exhaust gas, which passes through the primary heat exchanger 25 and then the secondary heat exchanger 27, is exhausted to the outside of the latent heat recovery water heater 1 from the exhaust outlet 49 of the combustion exhaust path 35.

[0029] Drain water generated on the surface of the heat receiving tube 26 of the secondary heat exchanger 27 during combustion drips and is guided by the inclined bottom plate 29 to the condensation water flow path 32, where it is neutralized in a neutralizer 37 equipped with a neutralizing agent whose main component is calcium carbonate.

[0030] In Figure 4, the shaded area indicates drain water. The drain water neutralized in the neutralizer 37 flows through the first piping section 41, which is the drain discharge piping 40, the pump 42, and the rising section 43, and forms a water-sealed state in the water seal section 46, which has one water surface of the drain water inside the neutralizer 37 and the other water surface inside the rising section 43. When the amount of drain water generated increases and the full water detection means 38 provided in the neutralizer 37 detects that the neutralizer 37 is full (Figure 4(a)), the control unit 60 drives the pump 42, sends the drain water in the neutralizer 37 to the first piping section 41, the rising section 43, and the auxiliary section 44, and discharges it outside the appliance through the drain outlet 44a (Figure 4(b)).

[0031] The control unit 60 is configured to turn the pump 42 off a first time period (e.g., 10 seconds) after the pump 42 is turned on. Until the pump 42 is turned off, the drain water in the neutralizer 37 and the first piping unit 41 is sent to the rising unit 43, flows through the auxiliary unit 44 connected to the upper end 43a of the rising unit 43, and is then discharged outside the appliance via the drain outlet 44a (FIG. 4(c)). The pump 42 has a discharge capacity that allows it to drain almost all of the drain water in the neutralizer 37 within the first time period. Alternatively, the first time period may be defined as a time period that allows it to drain almost all of the drain water in the neutralizer 37 using the drainage capacity of the pump 42.

[0032] When the pump 42 is turned off, the drain water is configured to be able to flow between the upstream and downstream sides of the pump 42, so that the drain water in the internal volume from the inlet of the rising section 43 to the upper end 43a flows back to the upstream side, which is the inlet side, due to its own weight. At this time, air flows in from the atmosphere communication section 44b, which communicates with the atmosphere, so that the drain water in the rising section 43 does not flow downstream but can flow back to the upstream side of the rising section 43 (FIG. 4(d)).

[0033] After the pump 42 is turned off, the control unit 60 checks, using the water seal detection means 45, whether the water seal unit 46 is sealed with water after a second time (for example, 30 seconds) has elapsed.

[0034] In the present invention, the water level at which the water seal detection means 45 detects that a water seal has been established is defined as the first water level, the sum of the internal volumes of the neutralizer 37, the first piping section 41, and the pump 42 below the first water level is defined as V1, and the internal volume of the portion downstream of the pump 42 that is higher than the first water level and lower than the height of the upper end 43a of the rising section 43 is defined as V2.As a result, the water level of the backflowing drain water is equal to or higher than the first water level, ensuring a water seal in the water seal section 46, and enabling the water seal detection means 45 to detect that a water seal has been established (Figure 4 (e)).

[0035] The explanation will be based on FIG.

[0036] In parallel with the combustion control of the burner unit 8, when the full water detection means 38 of the neutralizer 37 detects a full water state, the control unit 60 carries out a drainage process of the neutralizer 37 in the following manner. If a full water state is detected by the full water detection means 38 in step S1, the pump 42 is turned on in step S2, and the first timer is reset (step S3). After the first timer has elapsed a first time (e.g., after 10 seconds), the pump 42 is turned off (step S5). Then, after the first timer has elapsed a second time (e.g., after 30 seconds) (step S7), if the water seal detection means 45 detects that the water seal is in a water sealed state, the process transitions to step S1; if it detects that the water seal is not in a water sealed state, the operation of the latent heat recovery water heater 1 is stopped in step S9, and an error message is issued indicating that the water seal has been broken. The second time is determined based on the time required for drain water at a position higher than the first water level in the rising section 43 to flow back through the pump 42 and for the water level in the neutralizer 37 and the water level in the rising section 43 to equilibrate.

[0037] Next, a second embodiment will be described with reference to FIGS.

[0038] The difference between the first and second embodiments is that in the first embodiment, the pump 42 is turned off when a first time has elapsed since the pump 42 was turned on, whereas in the second embodiment, as shown in FIG. 6, a water seal detection means 45 is provided in the neutralizer 37, which is upstream of the pump 42, and the pump 42 is turned off when the water level of the drain water in the neutralizer 37 drops to a predetermined water level (specifically, below the water level of the water level detection electrode 45a).

[0039] In FIG. 7, as in FIG. 4, the shaded areas indicate drain water. The drain water neutralized in the neutralizer 37 flows through the first piping section 41, which is the drain discharge piping 40, the pump 42, and the rising section 43, and forms a water-sealed state in the water seal section 46, which has one water surface of the drain water inside the neutralizer 37 and the other water surface inside the rising section 43. Then, when the amount of drain water generated increases and the full water detection means 38 provided in the neutralizer 37 detects that the neutralizer 37 is full (Figure 7(a)), the control unit 60 drives the pump 42, sends the drain water in the neutralizer 37 to the first piping section 41, the rising section 43, and the auxiliary section 44, and discharges it outside the appliance through the drain outlet 44a (Figure 7(b)).

[0040] The control unit 60 is configured to turn off the pump 42 when the water level drops to a level at which the water seal detection means 45 detects that the pump 42 is not in a water-sealed state after the pump 42 is turned on.Until the pump 42 is turned off, the drain water in the neutralizer 37 and the first piping unit 41 is sent to the rising unit 43, flows through the auxiliary unit 44 connected to the upper end 43a of the rising unit 43, and is then discharged outside the appliance via the drain outlet 44a (Figure 7(c)).

[0041] When the pump 42 is turned off, the drain water is configured to be able to flow between the upstream and downstream sides of the pump 42, so that the drain water in the internal volume from the inlet of the rising section 43 to the upper end 43a flows back to the upstream side, which is the inlet side, due to its own weight. At this time, air flows in from the atmosphere communication section 44b, which communicates with the atmosphere, so that the drain water in the rising section 43 does not flow downstream but can flow back to the upstream side of the rising section 43 (FIG. 7(d)).

[0042] After the pump 42 is turned off, the control unit 60 checks, using the water seal detection means 45, whether the water seal unit 46 is sealed with water after a second time (for example, 30 seconds) has elapsed.

[0043] In the present invention, the water level at which the water seal detection means 45 detects that a water seal has been established is defined as the first water level, the sum of the internal volumes of the neutralizer 37, the first piping section 41, and the pump 42 below the first water level is defined as V1, and the internal volume of the portion downstream of the pump 42 that is higher than the first water level and lower than the height of the upper end 43a of the rising section 43 is defined as V2.As a result, the water level of the backflowing drain water is equal to or higher than the first water level, ensuring a water seal in the water seal section 46, and enabling the water seal detection means 45 to detect that a water seal has been established (Figure 7 (e)).

[0044] The explanation will be based on FIG. In parallel with the combustion control of the burner unit 8, when the full water detection means 38 of the neutralizer 37 detects a full water state, the control unit 60 carries out a drainage process of the neutralizer 37 in the following manner. If the full water state is detected by the full water detection means 38 in step S10, the pump 42 is turned on in step S11. If the level of drain water in the neutralizer 37 drops and the water seal detection means 45 detects that the water seal is not in place (step S12), the pump 42 is turned off (step S13). Next, after the first timer has elapsed for a second time (e.g., 30 seconds) (step S15), if the water seal detection means 45 again detects a water seal state in step S16, the process transitions to step S1, and if it detects that the water seal state is not present, the operation of the latent heat recovery water heater 2 is stopped in step S17, and an error message is issued indicating that the water seal has been broken.

[0045] Next, a third embodiment will be described with reference to FIGS.

[0046] The difference between the first and third embodiments is that the first embodiment is provided with a water seal section 46 that seals with water on the upstream and downstream sides of the pump 42, whereas the third embodiment is provided with a water seal section 46 on the upstream side of the pump 42, and the positions of the pump 42 and the water seal section 46 are different from those of the first embodiment. In the third embodiment, the pump is located at a height where it is submerged when the water level in the neutralizer 37 is full, and the water seal detection means 45 is disposed upstream of the pump . The water seal section 46 is a U-shaped pipe formed by connecting a part of the neutralizer 37 and the first piping section 41 to form a water seal.

[0047] In FIG. 10, as in FIG. 4, the shaded areas indicate drain water. The drain water neutralized in the neutralizer 37 flows through the first piping section 41, and forms a water-sealed state in the water seal section 46, which has one water surface of the drain water inside the neutralizer 37 and the other water surface inside the first piping section 41. Then, when the amount of drain water generated increases and the full water detection means 38 provided in the neutralizer 37 detects that the neutralizer 37 is full (Figure 10(a)), the control unit 60 drives the pump 42 to send the drain water in the neutralizer 37 to the first piping section 41, the rising section 43, and the auxiliary section 44, and discharges it outside the appliance through the drain outlet 44a (Figure 10(b)).

[0048] The control unit 60 is configured to turn the pump 42 off when a first time period (e.g., 10 seconds) has elapsed since the pump 42 was turned on, and until the pump 42 is turned off, the drain water in the neutralizer 37 and the first piping unit 41 is sent to the rising unit 43, flows through the auxiliary unit 44 connected to the upper end 43a of the rising unit 43, and is then discharged outside the appliance via the drain outlet 44a (FIG. 10(c)). The pump 42 has a discharge capacity that allows it to discharge substantially all of the drain water in the neutralizer 37 within the first time period.

[0049] When the pump 42 is turned off, the drain water is configured to be able to flow between the upstream and downstream sides of the pump 42, so that the drain water in the internal volume from the inlet of the rising section 43 to the upper end 43a flows back to the upstream side, which is the inlet side, due to its own weight. At this time, air flows in from the atmosphere communication section 44b, which communicates with the atmosphere, so that the drain water in the rising section 43 does not flow downstream but can flow back to the upstream side of the rising section 43 (FIG. 10(d)).

[0050] After the pump 42 is turned off, the control unit 60 checks, using the water seal detection means 45, whether the water seal unit 46 is sealed with water after a second time (for example, 30 seconds) has elapsed.

[0051] In the present invention, the water level at which the water seal detection means 45 detects that a water seal has been established is defined as the first water level, the sum of the internal volumes of the neutralizer 37, the first piping section 41, and the pump 42 below the first water level is defined as V1, and the internal volume of the portion downstream of the pump 42 that is higher than the first water level and lower than the height of the upper end 43a of the rising section 43 is defined as V2.As a result, the water level of the backflowing drain water is equal to or higher than the first water level, ensuring a water seal in the water seal section 46, and enabling the water seal detection means 45 to detect that a water seal has been established (Figure 10 (e)).

[0052] This allows drain water to be discharged from a high position above the housing 5, so even if the drain water is combined with the drain water from, for example, a domestic washing machine 81, the force of the drain water from the domestic washing machine 81 will not cause the washing machine's drain water to flow into the housing 5, thereby expanding the options for drain water discharge methods and increasing the freedom of installation, and making it possible to provide a latent heat recovery water heater 3 in which the drain water in the rising section 43 flows back after the pump 42 is stopped, ensuring water sealing of the drain discharge piping 40.

[0053] In the third embodiment, it was explained that the water seal section 46 is formed by connecting a part of the neutralizer 37 and the first piping section 41 to form a U-shaped pipe and achieve a water-sealed state, but the water seal section 46 may also be formed by forming the first piping section 41 in a U-shaped pipe shape and achieving a water-sealed state.

[0054] Although the burner unit 8 has been described as a pressure spray gun burner, other combustion burners may be used. Also, the positional relationship between the burner unit 8 and the primary heat exchanger 25 may be upside down.

[0055] It should be noted that the other configurations used in this embodiment are presented as examples and are not intended to limit the scope of the invention, and the invention can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are also included in the inventions described in the claims and their equivalents. [Explanation of symbols]

[0056] 1, 2, 3: Latent heat recovery water heater 8: Burner section 37: Neutralizer 37a: Neutralizer inlet 37b: Neutralizer outlet 38: Full water detection means 40: Drain discharge piping 41: First piping section 42: Pump 43: Ascending section 43a: Upper end 44: Auxiliary part 44a: Drain outlet 44b: Atmospheric communication part 45: Water seal detection means 46: Water seal part 60: Control section

Claims

1. The drain water generated when the combustion exhaust gas after combustion in the burner falls below the dew point is neutralized by passing it through a neutralizer filled with a neutralizing agent in advance. a drain discharge pipe connected to the neutralizer on the downstream side of the neutralizer; The neutralizer is a neutralizer inlet into which drain water flows; a neutralizer outlet for discharging drain water after neutralization; a full water detection means for detecting full water in the neutralizer; and The drain discharge pipe is a first piping section communicating with the neutralizer outlet; a pump communicating with the downstream end of the first piping section and discharging drain water from the neutralizer to the outside of the appliance; an ascending portion in communication with the downstream end of the pump; an auxiliary portion communicating with the upper end of the rising portion; and The auxiliary unit includes: A drain outlet at the downstream end, an atmosphere communication part that communicates drain water in the auxiliary part with the atmosphere; and a water seal portion that seals water on the upstream side of the pump or on the upstream side and downstream side of the pump; a water seal detection means for detecting whether or not the water level is equal to or higher than the water level when the water seal portion is water-sealed; a control unit that controls the burner unit and the pump; Furthermore, The pump is configured to allow drain water to flow between the upstream side and the downstream side of the pump when the pump is off, The water level at which the water seal detection means detects that a water seal is formed is defined as a first water level, V1 is the sum of the internal volumes of the neutralizer, the first piping section, and the pump below the first water level, If the internal volume of a portion downstream of the pump that is higher than the first water level and lower than the height of the upper end of the rising portion is V2, The relationship is V1≦V2 A latent heat recovery type water heater characterized by the above.

2. When the full water detection means detects full water, the control unit drives the pump on to discharge the drain water of the neutralizer to the outside of the appliance, and turns the pump off after a first time has elapsed since the drive on.

2. The latent heat recovery type water heater according to claim 1.

3. The water seal detection means is provided on the upstream side of the pump, When the full water detection means detects a full water state, the control unit drives the pump on to discharge the drain water from the neutralizer to the outside of the appliance, and when the water seal detection means does not detect a water seal, the control unit drives the pump off.

2. The latent heat recovery type water heater according to claim 1.

Images