JP2012177505A - Water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water heater capable of reliably preventing or suppressing a problem about inflow of rainwater into a neutralizing device, while suppressing complication of a structure or increase in size.SOLUTION: The water heater includes a neutralizing device 5, which recovers and neutralizes condensed water generating associated with heat recovery from a combustion gas by a heat exchanger 3B. The water heater includes rainwater intrusion detecting means Sa, 6, which can detect intrusion of rainwater when rainwater intrudes into an exhaust port 40 of an exhaust top 4. When intrusion of rainwater into the exhaust port 40 is detected by the rainwater intrusion detecting means Sa, 6 during driving of a burner 1 and a fan 2 is stopped, the fan 2 is driven to blow air to the outside of the water heater trough the exhaust port 40.

Description

  The present invention relates to a hot water apparatus such as a hot water supply apparatus, and more particularly to a hot water apparatus of a type that performs hot water heating by recovering heat from combustion gas using a heat exchanger.

  As the hot water device, there is a latent heat recovery type. The latent heat recovery type hot water apparatus recovers latent heat in addition to sensible heat when recovering heat from the combustion gas generated by the burner. When latent heat is recovered from the combustion gas, strongly acidic condensate containing components such as sulfur oxide and nitrogen oxide in the combustion gas is generated. Therefore, in the latent heat recovery type hot water apparatus, it is usual that the condensed water is sent to the neutralization apparatus to be neutralized and then discharged outside the apparatus. On the other hand, when a hot water apparatus placed outdoors is actually used, rainwater may enter the case of the heat exchanger from the exhaust outlet of the exhaust top attached to the heat exchanger when the wind and rain are strong. . If this rainwater flows into the neutralizing device through the condensed water flow path, for example, the neutralizing agent used in the neutralizing device is consumed, and the service life is shortened.

  As means for dealing with such problems, there are means described in Patent Documents 1 and 2. In Patent Document 1, an inclined wall for preventing rainwater ingress is provided in a location near the exhaust port in the exhaust top. This inclined wall is intended to prevent rainwater that has entered the exhaust top from the exhaust port from proceeding further toward the heat exchanger, and rainwater flows into the neutralizer due to the presence of this inclined wall. Is prevented. On the other hand, in Patent Document 2, when a bypass pipe is branched and connected via a switching valve in the middle of the condensed water piping path connecting the heat exchanger and the neutralizing device, and the burner is not driven and burned, The flow path is switched to the bypass pipe. According to such a configuration, even if rainwater enters the case of the heat exchanger, the rainwater does not flow into the neutralizer.

  However, there is still room for improvement in the prior art as described below.

  That is, in Patent Document 1, since it is necessary to provide an inclined wall for preventing rainwater ingress in the exhaust top, there is a problem that the exhaust top becomes large and its structure becomes complicated. In order to enhance the rainwater ingress prevention effect, the inclination angle of the inclined wall needs to be considerably increased, and thus the above-described problems become more prominent.

  On the other hand, in patent document 2, it is necessary to attach the detour piping provided with the switching valve for preventing rainwater from flowing in in a neutralization apparatus to a warm water apparatus. Therefore, the structure is complicated by that amount, and the manufacturing cost of the hot water device is increased.

JP 2006-284041 A JP 2009-287814 A

  The present invention has been conceived under the circumstances as described above, and appropriately prevents or prevents the inflow of rainwater into the neutralization device while suppressing the complexity and size of the structure. An object of the present invention is to provide a hot water device that can be suppressed.

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

  A hot water apparatus provided by the present invention has a fan for supplying combustion air to a burner and a case containing a heat transfer tube, and recovers heat from the combustion gas generated by the burner and flowing into the case. A heat exchanger to be performed, an exhaust top configured to be integrated with or separate from a case of the heat exchanger, and having an exhaust port for discharging the combustion gas subjected to the heat recovery to the outside of the apparatus, and the heat recovery. And a neutralizing device that collects the condensed water generated and neutralizes the condensed water, and a hot water device, when rainwater enters the exhaust port, Rainwater intrusion detection means capable of detecting the effect, and when the rainwater intrusion detection means detects that rainwater has entered the exhaust port when the burner and the fan are stopped driving, § emission is driven, it is characterized by being configured to blowout of air to the outside is made from the exhaust port.

  According to such a configuration, the fan is driven at the time when the ingress of rainwater into the exhaust port is detected even during the operation standby (stop) period of the hot water apparatus in which the drive of the burner and the fan is stopped. The rainwater is prevented from entering the exhaust port by the air blowing action from the exhaust port to the outside of the machine. Therefore, it is possible to appropriately prevent or suppress the possibility that a lot of rainwater flows into the neutralizing device. In the present invention, a fan and rainwater intrusion detection means are used as means for suppressing rainwater from entering the exhaust port. The fan is for supplying combustion air to the burner. In general, a general hot water apparatus is provided. As will be described later, the rainwater intrusion detection means can be configured simply by using a water level sensor provided in the neutralization device as it is. For this reason, in this invention, compared with patent document 1, 2 mentioned above, it becomes a thing preferable in preventing the enlargement of an apparatus, the complexity of a structure, etc.

  In the present invention, preferably, the neutralization device includes a neutralization treatment tank in which the condensed water flows in and the condensed water that has been subjected to the neutralization treatment is discharged to the outside, and the condensed water in the neutralization treatment tank. A water level sensor capable of detecting the water level or a change in the water level, and the rainwater intrusion detection means is configured using the water level sensor, and in the neutralization tank when the burner is stopped. When a rise in water level is detected using the water level sensor, it is determined that rainwater has entered the exhaust port.

  According to such a configuration, the water level sensor of the neutralizer is effectively used as rainwater intrusion detection means, and the configuration is reasonable. Apart from the water level sensor, it is not necessary to use a sensor dedicated to rainwater intrusion detection, which is more preferable for suppressing an increase in manufacturing cost.

  In the present invention, preferably, when the drive of the burner is stopped when the fan starts driving due to a rise in the water level in the neutralization tank, the driving time is set to a preset time, When the time elapses, when the water level drop in the neutralization treatment tank is not detected using the water level sensor, the fan is continuously driven for a preset time thereafter. ing.

  According to such a configuration, it is possible to prevent the fan from being driven unnecessarily for a long time after the state in which rainwater flows into the neutralizing device is completed. On the other hand, when the state where the rainwater flows into the neutralization device is not completed, the fan continues to be driven, so that the state where the ingress of rainwater is suppressed is appropriately maintained, and the condensed water into the neutralization device is maintained. The effect of reducing the inflow is obtained.

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

It is a schematic side sectional view showing an example of a hot water device according to the present invention. It is a flowchart which shows an example of the operation processing procedure of the control part of the hot water apparatus shown in FIG. It is principal part side surface sectional drawing which shows the other example of the hot water apparatus which concerns on this invention.

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

  A hot water apparatus WH shown in FIG. 1 is configured as a hot water supply apparatus, and includes a burner 1, a fan 2, primary and secondary heat exchangers 3A and 3B, an exhaust top 4, a neutralizer 5, a control unit 6, and An outer case 7 is provided for enclosing and protecting them.

  The burner 1 is a gas burner for burning fuel gas, for example, and is disposed in the can 8. The fan 2 is attached to the lower part of the can body 8 and supplies combustion air upward to the burner 1. As will be described later, the fan 2 is also used as a means for preventing rainwater from entering the exhaust top 4 during standby of the hot water apparatus WH.

  The primary and secondary heat exchangers 3A and 3B have heat transfer tubes 30a and 30b, and pass through the heat transfer tubes 30a and 30b by performing heat recovery from the combustion gas generated by the burner 1. Hot water can be heated. The primary heat exchanger 3 </ b> A is for sensible heat recovery, and the heat transfer tube 30 a is located in the can body 8. The secondary heat exchanger 3B is for recovering latent heat, and has a case 31 that accommodates the heat transfer tube 30b therein. The secondary heat exchanger 3B is provided on the upper side of the primary heat exchanger 3A, and the combustion gas that has passed upward through the primary heat exchanger 3A flows from the air supply port 32 provided at the rear of the case 31 to the case 31. It flows in and proceeds toward the front part of the case 31. In this process, latent heat recovery is performed by the heat transfer tube 30b. The exhaust top 4 is a member that guides and discharges the combustion gas that has traveled up to the front of the case 31 after heat recovery to the outside (outside of the machine) of the outer case 7. have. The strongly acidic condensate generated with the recovery of latent heat by the secondary heat exchanger 3B is discharged through a discharge port 33 provided at the bottom of the case 31 and a pipe channel 58 connected to the discharge port 33. It is sent to the summing device 5.

  The neutralizer 5 includes a neutralization tank 50 that contains a neutralizing agent 51 therein, and a water level sensor Sa. The neutralizing agent 51 is, for example, granular calcium carbonate. The neutralization treatment tank 50 has a condensed water inlet 56a and a discharge outlet 56b, and the condensed water that has passed through the pipe flow path 58 from the secondary heat exchanger 3B passes through the inlet 56a. 50, flows through the gap between the neutralizing agents 51, reaches the discharge port 56 b, and is then discharged to the outside of the exterior case 7 through the pipe flow path 59.

  The water level sensor Sa is configured using, for example, a pair of electrodes 57 to which a voltage is applied, and is attached to the upper portion of the neutralization tank 50. When the water level of the condensed water rises above the lower end level L of the pair of electrodes 57, they are conducted and the rise in the water level can be detected. This water level sensor Sa inherently detects when the condensed water in the neutralization tank 50 has abnormally increased due to clogging in the neutralization tank 50 or the pipe flow path 59. belongs to. However, in the present embodiment, the water level sensor Sa corresponds to a component of the “rainwater intrusion detection means” in the present invention.

The reason why rainwater intrusion detection is possible using the water level sensor Sa is based on the following logic. That is, since the condensed water is not generated when the burner 1 is stopped, the water level in the neutralization tank 50 should not rise. However, when rainwater blows into the exhaust port 40 of the exhaust top 4, the rainwater passes through the pipe flow path 58 and flows into the neutralization treatment tank 50, and the amount of the inflow is neutralized by the neutralization treatment tank 50. When the wastewater treatment capacity is exceeded, the water level in the neutralization treatment tank 50 rises. Therefore, when the water level rise is detected using the water level sensor Sa while the burner 1 is stopped, it can be determined that a large amount of rainwater has entered the exhaust port 40. is there.

  The control unit 6 performs operation control and data processing of each unit of the hot water device WH, and drives the fan 2 based on the detection signal from the water level sensor Sa when the drive of the burner 1 and the fan 2 is stopped. The control to be executed is executed. Although details of this control will be described later, when the fan 2 is driven, air is blown out from the exhaust port 40, and this causes an effect of preventing rainwater from entering.

  Next, the operation of the hot water apparatus WH will be described with reference to the flowchart shown in FIG.

  First, when the hot water device WH is in the operation standby state and the drive of the burner 1 and the fan 2 is stopped, the water level in the neutralization tank 50 rises and the water level sensor Sa is turned on, and this on state. Is continued for a predetermined time such as several seconds, for example, the control unit 6 starts driving the fan 2 (S1: YES, S2: YES, S3: YES, S4). As described above, it is considered that the reason why the water level in the neutralization tank 50 rises when the burner 1 and the fan 2 are stopped is that rainwater has entered the exhaust port 40. Therefore, if the driving of the fan 2 is started on the condition that the water level sensor Sa is turned on as described above, the air is discharged from the exhaust port 40 when rainwater is blown into the exhaust port 40. Can be blown out. Since the blowing of air can suppress the inflow of rainwater into the exhaust port 40, the amount of rainwater flowing into the neutralization tank 50 is reduced, and the consumption of the neutralizing agent 51 due to the inflow of rainwater is suppressed. be able to.

  In step S3, the condition that the ON state of the water level sensor Sa is continued for a predetermined time or more is that, for example, when the hot water device WH is shaken and the condensed water in the neutralization tank 50 is in a wavy state. Even so, the water level sensor Sa may be turned on, so that the fan 2 is prevented from being driven in such a case. The drive rotation speed of the fan 2 may be low, for example, the lowest speed when the burner 1 is driven. When the driving rotation speed of the fan 2 is increased, the negative pressure state in the outer case 7 becomes significant due to the intake operation of the fan 2, and water droplets adhering to the outer surface of the outer case 7 are caused by the negative pressure. Therefore, there is a risk of entering the outer case 7 from an appropriate gap. If the drive rotation speed of the fan 2 is set to a low speed, such a fear can be eliminated.

  Even if rainwater actually flows into the neutralization treatment tank 50, the amount of inflow is small and the neutralization treatment capacity of the neutralization treatment tank 50 is not exceeded. There is no water level rise in tank 50. In this case, the water level sensor Sa is not turned on (S2: NO), and the fan 2 is not driven, so that rainwater intrusion cannot be prevented by air blowing from the exhaust port 40. Therefore, in this warm water device WH, there is a possibility that a small amount of rainwater flows into the neutralization tank 50. However, the depletion of the neutralizing agent 51 is intense when a large amount of rainwater flows into the neutralization treatment tank 50, and the small amount of rainwater causes little depletion of the neutralizing agent 51, and there is no particular problem. In this hot water device WH, as described above, since a large amount of rainwater is prevented from flowing into the neutralization treatment tank 50, this can appropriately prevent the neutralizing agent 51 from being consumed. is there.

  When the controller 6 starts driving the fan 2 as described above, the controller 6 sets a predetermined time (for example, 5 to 10 minutes) along with this, and when this time has elapsed, the water level sensor It is determined whether Sa is still on (S5, S6: YES, S7). When the inflow of rainwater into the neutralization treatment tank 50 stops or the inflow amount of rainwater decreases and the water level in the neutralization treatment tank 50 falls below a predetermined level L, the water level sensor Sa is not in the ON state. . In this case, the controller 6 stops driving the fan 2 (S7: NO, S9). Thereby, it is possible to prevent the fan 2 from being driven wastefully for a long time.

  Unlike the above, when the water level in the neutralization tank 50 is still higher than the predetermined level L and the water level sensor Sa is still on (S7: YES), the control unit 6 stops driving the fan 2. I won't let you. In this case, the control unit 6 performs a timer reset and repeats steps S6 and S7 described above. For this reason, in this hot water apparatus WH, unless the water level in the neutralization tank 50 is lowered and the water level sensor Sa is turned off, the drive rotation of the fan 2 is continued, and the air blowing from the exhaust port 40 is continued. Can prevent rainwater from entering. When driving the fan 2 is continued, it is possible to increase the rotational speed of the fan 2 by a predetermined speed. In addition, the flowchart shown in FIG. 2 is an operation process at the time of operation standby of the hot water device WH. Although not shown in the figure, when the burner 1 is driven and the hot water apparatus WH is in an operating state, the above-described operation processing is interrupted at that time.

  FIG. 3 shows another embodiment of the present invention.

  In the embodiment shown in FIG. 3, the flow rate sensor Sb is provided in the piping path 58 for guiding the condensed water generated in the secondary heat exchanger 3 </ b> B to the neutralization treatment tank 50 of the neutralization device 5. The flow rate sensor Sb is a constituent element of the “rainwater intrusion detection means” referred to in the present invention. When flowing water is detected by the flow rate sensor Sb when driving of the burner 1 where no condensed water is generated, this flowing water is rainwater that has entered the case 31 of the secondary heat exchanger 3B from the exhaust port 40. Therefore, this flow sensor Sb can be used as rainwater intrusion detection means. The control unit 6 is configured to execute control to drive the fan 2 at that time when flowing water of a predetermined flow rate or more is detected by the flow rate sensor Sb when driving of the burner 1 and the fan 2 is stopped. Has been.

  According to the present embodiment, when a situation occurs in which rainwater enters the case 31 of the secondary heat exchanger 3B, air can be blown out from the exhaust port 40 as in the above-described embodiment. When the flow sensor Sb is used, this can be detected even when the amount of rainwater entering is relatively small. Therefore, unlike the above-described embodiment, even if the amount of condensed water flowing into the neutralization treatment tank 50 does not exceed the neutralization wastewater treatment capacity of the neutralization treatment tank 50, rainwater enters the exhaust port 40. Can be detected and the fan 2 can be driven.

  The present invention is not limited to the contents of the above-described embodiment. The specific configuration of each part of the hot water device according to the present invention can be variously modified within the scope intended by the present invention.

  The rainwater intrusion detection means referred to in the present invention may be any means that can detect that when rainwater enters the exhaust outlet of the exhaust top, and when rainwater enters the exhaust outlet. This need not be detectable in all cases. As described above, in the embodiment shown in FIG. 1, the ingress of rainwater can be detected only when the amount of rainwater flowing into the neutralization treatment tank exceeds the neutralization drainage treatment capacity of the neutralization treatment tank. However, the configuration may be such that it is detected only when rainwater that satisfies a specific condition occurs in this way. As rainwater intrusion detection means, instead of using a water level sensor provided in the neutralization device or a flow sensor provided in the flow path of rainwater entering the exhaust port, a sensor different from these is used. It is also possible.

  The exhaust top referred to in the present invention is a means for guiding and discharging the combustion gas after heat recovery by the heat exchanger to the outside of the machine, and is not limited to being formed separately from the case of the heat exchanger. Alternatively, the heat exchanger can be formed integrally with the case of the heat exchanger. For example, as shown in FIG. 1, when the distance between the case 31 of the secondary heat exchanger 3B and the outer case 7 is relatively short, a part of the case 31 can be configured as an exhaust top. is there. Of course, the exhaust top may be formed in a duct shape having a relatively long dimension, and its specific form is not limited, such as one extending sideways or one extending upward.

  The neutralization apparatus should just have the function to neutralize acidic condensed water, and is not limited to the thing using the neutralizer of calcium carbonate. The heat exchanger may have a configuration in which the heat transfer tube is provided in the case into which the combustion gas flows, and the specific form of the heat transfer tube is not limited. Further, the heat exchanger is not limited to one separated into a primary heat exchanger for sensible heat recovery and a secondary heat exchanger for latent heat recovery, and both sensible heat and latent heat are obtained by one heat exchanger. It can also be set as the structure which can collect | recover sequentially. As the burner, for example, an oil burner can be used instead of the gas burner.

  The hot water device as used in the present invention means a device having a function of generating hot water, and is used for various types of hot water supply devices for general hot water supply, bath hot water supply, heating, snow melting, and the like, and hot water supply. It is a concept that includes a wide range of equipment for producing hot water.

WH Water heater Sa Water level sensor (Rainwater intrusion detection means)
Sb flow sensor (rainwater intrusion detection means)
DESCRIPTION OF SYMBOLS 1 Burner 2 Fan 3A, 3B Heat exchanger 4 Exhaust top 5 Neutralizing device 6 Control part 30a, 30b Heat transfer pipe 40 Exhaust port 50 Neutralization treatment tank 51 Neutralizing agent

Claims (3)

A fan for supplying combustion air to the burner;
A heat exchanger having a case containing a heat transfer tube and recovering heat from the combustion gas generated by the burner and flowing into the case;
An exhaust top configured to be integral with or separate from the case of the heat exchanger and having an exhaust port for discharging the combustion gas from which the heat has been recovered;
A neutralizer for recovering the condensed water generated along with the heat recovery and neutralizing the condensed water;
A hot water device comprising:
When rainwater intrudes into the exhaust port, it has rainwater intrusion detection means capable of detecting that,
When the rainwater intrusion detection means detects that rainwater has entered the exhaust port when the burner and the fan are stopped driving, the fan is driven and air is discharged from the exhaust port to the outside of the machine. It is comprised so that blowing of may be performed, The hot water apparatus characterized by the above-mentioned. The hot water device according to claim 1,
The neutralization device includes a neutralization treatment tank that allows the condensed water to flow into the interior and outflow the condensed water that has undergone the neutralization treatment to the outside, and a water level or a change in the water level in the neutralization treatment tank. With a water level sensor that can be detected,
The rainwater intrusion detection means is configured using the water level sensor, and when the water level rise in the neutralization tank is detected using the water level sensor when the burner is stopped, the exhaust port A water heater configured to determine that rainwater has entered the water. The hot water device according to claim 2,
When the fan stops driving when the fan starts driving due to the rise in the water level in the neutralization tank, the driving time is set to a preset time, and when this time elapses, When the water level drop in the neutralization tank is not detected using the water level sensor, the water heater is configured so that the fan continues to be driven for a preset time after that.

Images