JP5456915B2 - Bath water heater - Google Patents

Description

  The present invention relates to a bath water heater equipped with a hot water heat exchanger for collecting latent heat.

  FIG. 5 schematically shows an example of a hot water supply apparatus. Conventionally, various hot water supply apparatuses as shown in this figure have been proposed (see, for example, Patent Document 1).

  In the figure, a combustion chamber 50 (50a, 50b) is provided in the instrument case 40, a hot water supply burner 1 (1a, 1b, 1c) is provided in the combustion chamber 50a, and a bathtub 30 is provided in the combustion chamber 50b. A reheating burner 7 (7a, 7b) for reheating hot water is disposed.

  The hot water supply burner 1 and the reheating burner 7 are connected to gas pipes 42 for supplying fuel to the respective burners 1 and 7. The gas pipes 42 supply and stop fuel to the burners 1 and 7. An on-off valve 51 for control and a proportional valve (not shown) capable of controlling the amount of fuel supplied to the hot water supply burner 1 with the valve opening are provided.

  Below the hot water supply burner 1 and the reheating burner 7, combustion fans 5 and 10 for supplying and exhausting combustion of the respective burners 1 and 7 are provided, and the intake port ( The air sucked from the outside via the gas supply burner 1 and the reheating burner 7 is sent to the hot water burner 1 and the reheating burner 7, and burner combustion is performed by this air and the gas supplied through the gas pipe 42. Combustion gas generated by burner combustion passes through the combustion chamber 50 and is exhausted from an exhaust port (not shown).

  A hot water supply heat exchanger (primary hot water supply heat exchanger) 4 for recovering sensible heat in the combustion gas of the hot water supply burner 1 is disposed above the hot water supply burner 1, and the combustion is performed more than the main hot water supply heat exchanger 4. A latent heat recovery hot water supply heat exchanger (secondary hot water supply heat exchanger) 6 for recovering sensible heat and latent heat of the combustion gas is provided on the downstream side of the gas flow. Further, on the upper side of the reheating burner 7, there is provided a reheating heat exchanger 12 for reheating the bathtub hot water, and this reheating heat exchanger 12 is provided in a reheating circulation path 31 connected to the bathtub 30. It has been.

  The main hot water supply heat exchanger 4, the latent heat recovery hot water supply heat exchanger 6, and the reheating heat exchanger 12 are respectively arranged upright on a pipe line through which water passes and an outer peripheral surface of the pipe line with a space therebetween. And plate-like fins 3. In the bath water heater provided with the latent heat recovery hot water supply heat exchanger 6, a configuration in which fins are not provided on the outer peripheral side of the pipe line of the latent heat recovery hot water supply heat exchanger 6 is also used.

  A water supply passage 46 for introducing water from a water supply source is connected to the inlet side (water inlet side) of the latent heat recovery hot water supply heat exchanger 6, and is connected to the outlet side of the latent heat recovery hot water supply heat exchanger 6. The inlet side of the hot water supply heat exchanger 4 is connected. A hot water supply passage 47 is connected to the outlet side (outlet side) of the main hot water supply heat exchanger 4, and the bath hot water supply apparatus shown in FIG. 5 latently heats the water passing through the latent heat recovery hot water supply heat exchanger 6. The preheated water is preheated with the recovered heat, the preheated water is supplied to the water inlet of the main hot water supply heat exchanger 4, and the hot water heated by the main hot water supply heat exchanger 4 is fed into the hot water supply passage 47. It has a function of supplying hot water to the above hot water supply destinations.

  The water supply passage 46 has a flow rate sensor 43 for detecting the flow rate of water supplied from the water supply passage 46 and flowing into the latent heat recovery hot water supply heat exchanger 6 side, and water flowing into the latent heat recovery hot water supply heat exchanger 6. An incoming water thermistor (not shown) for detecting the incoming water temperature is provided, and a hot water thermistor (not shown) capable of detecting the temperature of hot water flowing out is provided in the hot water supply passage 47. Further, a recirculation circuit 31 is connected to the hot water supply passage 47 via a pouring connection path 26, and the pouring electromagnetic valve 27 and the amount of hot water to the bathtub 30 are detected in the pouring connection path 26. And a flow rate detecting means 15 is provided.

  The reheating circuit 31 includes a reheating heat exchanger 12, a return pipe 28 provided on the inlet side of the reheating heat exchanger 12, and an outgoing pipe provided on the outlet side of the reheating heat exchanger 12. 29, the forward pipe 29 and the return pipe 28 are connected to the side wall of the bathtub 30. The return pipe 28 includes a water level sensor 8 as a bathtub water level detection means for detecting the water level of the bathtub 30, a circulation pump 9 that circulates the bathtub hot water, and is turned on when it is detected that water has flowed through the return pipe 28. A flowing water detection sensor (flow water switch) 11 and a bath temperature sensor (not shown) for detecting the temperature of bathtub hot water are provided. The water level sensor 8 is formed by a pressure sensor that detects the bathtub water level by water pressure. In addition, the recirculation circuit 31 between the hot water supply apparatus and the bathtub 30 (the outgoing pipe 29 and the return pipe 28 between the hot water supply apparatus and the bathtub 30) has recently been often formed by a crosslinked polyethylene pipe or the like.

  Below the latent heat recovery hot water supply heat exchanger 6, a drain recovery means 48 that recovers drain generated in the latent heat recovery hot water supply heat exchanger 6, and a drain that stores the drain recovered by the drain recovery means 48. A drain tank 13 as a storage unit is provided, and the drain recovery unit 48 and the drain tank 13 are connected via a drain pipe 49.

  In the bath water heater provided with the latent heat recovery hot water supply heat exchanger 6, the water passing through the water pipe in the latent heat recovery hot water supply heat exchanger 6 from the water supply passage 46 is the combustion gas generated by the combustion of the hot water burner 1. When passing through the heat exchanger 6, the latent heat held by the water vapor in the combustion gas is taken away (collecting latent heat) to increase the temperature, and when passing through the main hot water supply heat exchanger 4, the hot water supply burner 1 Since the hot water having the set temperature is produced by being heated by the combustion thermal power of, efficient heating can be performed by the hot water supply burner 1.

  That is, by providing the hot water supply heat exchanger 6 for recovering latent heat, for example, in a hot water supply apparatus for a bath, the heat efficiency reaches about 90% or more on the basis of a high heat generation amount (total heat generation amount). High thermal efficiency is achieved compared to a normal bath water heater that is not provided. Therefore, a bath water heater with a hot water heat exchanger for collecting latent heat is attracting attention as a bath water heater capable of realizing energy saving (energy saving).

  In addition, since the said drain contains nitrogen oxide (NOx), sulfur oxide (SOx), etc. in combustion gas, it is a strong acidity of pH 2-4. Therefore, the bath water heater shown in FIG. 5 mixes this drain with warm water so that it can be used as an acidic spring. That is, in this example, a drain outlet path 16 that guides the drain stored in the drain tank 13 to the recirculation circulation path 31 side is provided, and the drain that is guided through the drain outlet path 16 passes through the recirculation circulation path 31. The structure which led to the bathtub 30 and mixed with bathtub hot water and made it into an acidic spring is provided.

  The drain outlet passage 16 is provided with a drain outlet valve 17 and a check valve 20 provided on the downstream side of the drain outlet valve 17. The drain outlet valve 17 is opened and hot water is filled in the bathtub 30. When the circulating pump 9 is driven in the state of being discharged, the hot water in the bathtub 30 is mixed by draining the hot water circulated from the bathtub 30 through the return pipe 28 to the outgoing pipe 29 and circulating again in the bathtub 30. It is configured to be an acidic spring.

  In the bath hot water supply apparatus, the combustion control of the hot water supply burner 1 and the reheating burner 7 and the rotation control of the combustion fans 5 and 10 are given in advance by a control device (not shown) based on the detection signals of the sensors. As described above, the hot water supply burner 1 and the reheating burner 7 are burned by the gas supplied from the gas pipe 42 and the air sent by the combustion fans 5 and 10, respectively. Operations such as hot water supply to the bath, bathing of the bathtub, and reheating of the bathtub hot water are appropriately performed.

  Below, an example of operation | movement of a bath water heater is demonstrated easily. The hot water supply operation is started, for example, by opening a hot water tap (not shown) in a kitchen or a washroom, for example. When detected, the hot water supply burner 1 is combusted and heated so that water passing through the hot water supply heat exchangers 4 and 6 (the main hot water supply heat exchanger 4 and the latent heat recovery hot water supply heat exchanger 6) becomes hot water of a set temperature, The hot water is supplied to the hot water supply destination through the hot water supply passage 47. When the flow rate sensor 43 detects the stop of water flow due to the closing of the hot-water tap, the control device shuts off the gas supply to the hot-water supply burner 1 and stops the combustion of the hot-water supply burner 1.

  The operation of the automatic hot water filling function is performed by automatic hot water filling means provided in the control device. This operation is started by turning on the automatic switch of the remote control device connected to the control device of the hot water bath apparatus, and the automatic hot water filling means receives the automatic switch on signal and receives the pouring electromagnetic valve 27. open. Similarly to the operation of the hot water supply function, water passing through the hot water supply heat exchangers 4 and 6 is converted into hot water by combustion heating of the hot water supply burner 1, and is passed from the hot water supply passage 47 to the pouring connection passage 26 and through the reheating circulation passage 31. Drop into bathtub 30.

  The automatic hot water filling means is preliminarily given hot water filling data (PQ data) as shown in FIG. 3, for example, showing the relationship between the bathtub water level (P) and the hot water amount (Q). The automatic filling means fills the bathtub 30 based on the filling data, the amount of filling water detected by the flow rate detection means 15, and the bathtub water level detected by the water level sensor 8. Although the detailed procedure for filling the hot water is various, based on the PQ data, a hot water having a water volume corresponding to a predetermined set water level is dropped into the bathtub 30, thereby being detected by the water level sensor 8. After confirming that the detected water level has reached the set water level, the hot water solenoid valve 27 is closed and the hot water filling operation is terminated. In this hot water filling operation, the control device controls the hot water temperature of the hot water supply heat exchangers 4 and 6 so as to have a preset hot water filling temperature.

  Usually, the operation of the heat retaining function is performed following the operation of the automatic hot water filling function, and the operation of the water retaining function is performed for those having the water retaining function. The operation of the heat insulation function is to start the circulation pump 9 for a short time at a predetermined time interval, recirculate hot water in the bathtub 30 and circulate it through the circulation path 31, and the hot water temperature of the bathtub 30 detected at this time is the setting of the bath. When the temperature falls outside the allowable range, the circulation pump 9 is driven to recirculate hot water in the bathtub 30 through the recirculation path 31 and is heated by the reheating heat exchanger 12 by the combustion of the reheating burner 7. (Performs a chasing operation). When the hot water temperature of the bathtub 30 reaches the set temperature of the bath, the combustion of the circulation pump 9 and the reheating burner 7 is stopped.

  As shown in FIG. 5, in the bath water heater configured to form an acidic spring using drain, the drain outlet valve 17 is opened as necessary during the reheating operation, and hot water is filled in the bathtub 30. By driving the circulation pump 9 in a state in which the water is discharged, the hot water in the bathtub 30 can be turned into an acidic spring by mixing drain with the hot water circulated in the bathtub 30 as described above.

Japanese Patent No. 3153361

  However, the drain is so-called waste water containing nitrogen oxides in the exhaust gas, and some users hate to use such drain in bath water. Therefore, it is conceivable that the drain is introduced into the bathtub 30 and discharged only when there is no hot water in the bathtub 30 without putting the drain into the bathtub hot water.

  In addition, the detection of the presence or absence of the residual water in the bathtub 30 can be performed as follows, for example. That is, when the circulating pump 9 provided in the recirculation circulation path 31 is driven and the hot water in the bathtub 30 is circulated through the recirculation circulation path 31, this flowing hot water flow is detected by the flow switch 11. Sometimes, it can be determined that there is residual water in the bathtub 30, and it can be determined that there is no residual water in the bathtub 30 when running water is not detected.

  However, the recirculation circulation path 31 is connected to the side wall of the bathtub 30, and when there is residual water in the bathtub 30 below the connection level of the recirculation circulation path 31, the circulation pump 9 is turned on. Even if it is driven, the hot water in the bathtub 30 does not flow and flows into the circulation path 31, so that it is determined that there is no residual water even if there is residual water. When drain is discharged to the bathtub 30 in a state where there is residual water, and the normal hot water filling is performed in that state, the hot water in the bathtub 30 becomes hot water mixed with drain. Therefore, it is a problem for users who are reluctant to use drain in bathtub water.

  Further, for example, a drain drain pump 44 and a drain discharge pipe are provided in the drain drain pipe 44, and the drain is drained directly to the drain outlet of the bathtub through the drain discharge pipe by the operation of the pump, A configuration for discharging to an external drainage channel has also been proposed, but this configuration requires a dedicated pump and conduit for drainage drainage, which increases costs and opens a hole through the house for the drainage tube. It is necessary to do this, so it will cost more. Further, in apartment houses such as apartments, if the liquid drainage is discharged as it is to a veranda or the like where a bath water heater is provided, there arises a problem that the user feels uncomfortable.

  The present invention has been made in order to solve the above-described conventional problems, and the object thereof is to solve the problem of drainage of the drain generated by the provision of the hot water heat exchanger for recovering latent heat to the outside of the apparatus. An object of the present invention is to provide a highly efficient bath water heater that can be easily installed.

  In order to achieve the above object, the present invention has the following configuration as means for solving the problems. That is, the first invention includes a hot water supply burner, a main hot water supply heat exchanger that absorbs sensible heat in the combustion gas of the hot water supply burner, and a downstream side of the flow of the combustion gas from the main hot water supply heat exchanger. A hot water supply heat exchanger for recovering latent heat that is disposed in the exhaust gas and a hot water supply passage connected to the outlet side of the main hot water supply heat exchanger, and a recirculation circuit connected to the side wall of the bathtub The recirculation circuit is provided with a circulation pump, and the recirculation circuit is communicated with the hot water supply passage through a pouring connection path, and the latent heat recovery hot water supply heat exchanger and the Automatic hot water filling means for feeding hot water heated through the main hot water supply heat exchanger to the bathtub through the pouring connection path and the recirculation circulation path, and detecting the bathtub water level Tub water level detection means to detect and the amount of hot water filling the bathtub The automatic hot water filling means includes a predetermined hot water filling data indicating the relationship between the bath water level and the hot water amount, and the hot water amount detected by the flow rate detecting means. A bath hot water supply apparatus having a structure for performing hot water filling to the bathtub based on the bathtub water level detected by the bathtub water level detection means, and recovers the drain generated in the hot water heat exchanger for recovering latent heat. Drain recovery means, drain storage means for storing drain recovered by the drain recovery means, and drain stored in the drain storage means to the conduit between the bathtub of the recirculation circulation path and the suction side of the circulation pump When the amount of drain stored in the drain storage means is equal to or greater than a predetermined drainage reference amount, the circulation pump is driven to cause the drain to flow into the drain guide path and the additional drain. A drain discharge control means for discharging through the water circulation circuit, and when the automatic hot water filling means performs filling of the bathtub after the drain discharge by the drain discharge control means, the interior of the bathtub is empty. When the hot water is dropped into the bathtub in the state of the water level, the water level can be detected by the bathtub water level detection means. A water level comparison operation that performs a water level comparison operation that compares the detection bath water level detected by the water level detection means with the bath water level of the hot water filling data corresponding to the drop amount of the hot water filling corresponding to the remaining water detection water level. And the water level comparing means determines that the value of the detected bathtub water level is greater than the value of the bathtub water level of the hot water filling data. A structure having a bathtub drainage notification means for performing notification for prompting the discharge of water is a means for solving the problem.

  Further, in the second invention, in addition to the configuration of the first invention, a three-way solenoid valve is provided to the outgoing pipe of the pipeline from the reheating heat exchanger to the bathtub in the recirculation circulation passage. A structure in which a drainage passage is connected, a drain flow path flowing from the circulation pump side to the bathtub side through the forward pipe is switched to the drainage passage by the three-way solenoid valve, and the drain is discharged into the bathroom through the drainage passage. It is provided.

  Further, in the third invention, in addition to the configuration of the first or second invention, the remaining water detection water level is a reference water level determined at an upper end portion of a recirculation circuit to the side wall of the bathtub. It is characterized by that.

  Furthermore, in the fourth invention, in addition to the configuration of the first, second or third invention, when the water level comparing operation is performed by the water level comparing means, the value of the detection bathtub water level is the data of the filling data. When it is larger than the value of the bathtub water level, it has a hot water stopping means for stopping the automatic hot water filling operation by the automatic hot water filling means.

  Furthermore, in addition to the configuration of any one of the first to fourth inventions, the fifth invention is predetermined after the drain discharge control means discharges or drains the drain through the recirculation circuit. Water supply control means for supplying a set amount of water to the bathtub through the recirculation circuit, and after the water supply by the water supply control means is completed, to the bathtub by the detected bathtub water level detected by the bathtub water level detection means and the automatic hot water filling means The water level comparing means compares the bathtub water level of the hot water filling data corresponding to the water volume obtained by adding the set water volume to the dropped water volume.

  According to the present invention, it has a hot water supply heat exchanger for latent heat recovery, preheats the water passing through the hot water heat exchanger for latent heat recovery with the heat of latent heat recovery, and uses the preheated water as a main hot water supply heat exchanger. Since this is a bath hot water supply device of the type that is supplied to the entrance side, it can be a highly efficient bath hot water supply device.

  Further, according to the present invention, when the hot water filling means is filled with the automatic hot water filling means after the drain discharge control means has discharged the hot water, the hot water in the bathtub is left empty. The water level comparison means is used by the bathtub water level detection means after the dropping of the filling water corresponding to the predetermined water level for residual water detection that can be detected by the bathtub water level detection means. A water level comparison operation is performed to compare the detected bathtub water level and the bathtub water level of the hot water filling data corresponding to the drop amount of the hot water corresponding to the remaining water detection water level. When it is determined that the detected bathtub water level is greater than the bathtub water level value of the hot water filling data, the bathtub drainage notification means Since the notification is made to prompt the person to go out (the notification can inform people who do not want to use the drain water in the bathtub hot water etc.) that the drain water is mixed in the bath water. It can be urged to discharge hot water. Therefore, it is possible to prevent the user from using the drained bathtub hot water by performing the hot water filling after discharging the drained bathtub hot water based on the notification.

  Further, in the present invention, drainage is performed using a recirculation circuit, so it is expensive to install a pipe for guiding the drain to the drainage port of the house, or liquid drainage is left on the veranda as it is. It is possible to prevent the user from having a very uncomfortable feeling by letting it flow out. For example, when the bath water heater is replaced, the bath water heater of the present invention which is a highly efficient bath water heater can be used. It can be applied easily and energy saving can be achieved.

  Furthermore, the present invention discharges drain to the bathtub through the recirculation circuit (through the recirculation circuit), so that, for example, drains with strong acidity are led to the recirculation circuit without being neutralized. By passing through the circulation circuit, the recirculation circuit can be sterilized with drainage with strong acidity, and the recirculation circuit can be maintained in a hygienic state so that the user can bathe comfortably. Can do. Further, if the drain is not neutralized, neutralizing means such as a neutralizing agent can be dispensed with, and cost can be saved.

  Further, in the present invention, if the water level for residual water detection is a reference water level determined at the upper end of the connection part of the recirculation circuit to the side wall of the bathtub, the minimum water level capable of detecting the presence or absence of residual water Can be used as the water level for residual water detection, and the amount of hot water can be minimized when the drain is mixed into the bath water and the bath water is discharged.

  Further, in the present invention, when the water level comparison operation is performed by the water level comparison means, if the detected bathtub water level value is larger (higher) than the bathtub water level value of the hot water filling data, the automatic hot water filling means. By providing the hot water filling stopping means for stopping the automatic hot water filling operation, when the bathtub drainage notification means issues a notification to prompt the discharge of hot water in the bathtub, the user does not have to stop the automatic hot water filling operation. The automatic filling operation can be automatically stopped. Therefore, at the time of notification by the bathtub drainage notification means, even if the user cannot respond immediately, waste of water and the like due to continuation of the automatic hot water filling operation can be eliminated.

  Furthermore, in the present invention, the water discharge control means for supplying a predetermined amount of water to the bathtub through the recirculation circulation path after the drain discharge control means discharges the drain to the bathtub through the recirculation circulation path or after discharging the drain. In the case of having the above, this operation can be performed more accurately by performing the water level comparing operation by the water level comparing means after the set amount of water is supplied. In other words, for example, when the water level for residual water detection is set as the reference water level, if there is very little residual water in the bathtub, hot water filling up to the reference water level after draining is performed. The bathtub water level is only slightly higher than the reference water level, and it may be difficult to detect the water level by the bathtub water level detection means. Even in this case, if the bathtub water level is detected after the water supply, the detection can be accurately performed, and the water level comparison operation can be easily and accurately performed.

  In addition, this configuration allows the drain water flow area in the recirculation circuit to be washed with water, so that it is possible to prevent the drain from remaining in the recirculation circuit or on the bottom of the bathtub, even if the drainage is highly acidic. Even if it is discharged to the bathtub through the recirculation circuit without neutralizing, the remaining drain can be washed away. In addition, if the said water is made into hot water through a hot water supply heat exchanger and is sent to the bathtub through the recirculation circuit, the drain cleaning effect can be further improved.

It is a block diagram which shows the drain discharge related control structure in 1st Example of the bath hot-water supply apparatus which concerns on this invention. It is explanatory drawing which shows typically the system configuration | structure of the said 1st Example. It is a graph which shows the example of the data for hot water filling. It is explanatory drawing which shows typically the system configuration | structure of 2nd Example of the hot-water supply apparatus which concerns on this invention. It is explanatory drawing which shows typically an example of the conventional bath hot-water supply apparatus provided with the hot water supply heat exchanger for latent-heat collection | recovery.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the present embodiment, the same reference numerals are assigned to the same name portions as those in the conventional example, and the duplicate description is omitted or simplified.

  FIG. 2 schematically shows the configuration of the first embodiment of the bath hot water supply apparatus according to the present invention. As in the conventional example shown in FIG. 5, the bath hot-water supply apparatus of the present embodiment has hot water supply to the kitchen and the hot water to the bathtub (hot water for hot water filling), and the function of reheating hot water in the bathtub. And a drain outlet path 16 that guides the drain stored in the drain tank 13 to the recirculation path 31, and recirculates the drain guided through the drain outlet path 16. A drain discharge control configuration for discharging to the bathtub 30 via the path 31 is provided.

  In the present embodiment, the latent heat recovery hot water supply heat exchanger 6 has no fins. Further, a drain neutralizing means 14 for neutralizing the drain stored in the drain tank 13 is provided on the upper side of the drain tank 13, and the drain neutralized by the drain neutralizing means 14 is stored in the drain tank 13. doing.

  Further, the present embodiment has a control configuration shown in FIG. That is, the control device 23 includes a drain liquid amount detection unit 2, a residual water presence / absence determination unit 35, a drain discharge control unit 38, a water supply control unit 39, an automatic hot water filling unit 33, a PQ data storage unit 36, and a water level comparison unit 32. In addition, automatic hot water filling stopping means 37 and bathtub drainage notification means 34 are provided, and bathtub drainage notification means 34 is connected to a speaker 77 of the remote control device.

  In the present embodiment, as described above, the automatic filling means 33 includes filling data (PQ data) as shown in FIG. 3, the amount of filling water detected by the flow rate detection means 15, and the water level. The hot water filling to the bathtub 30 is performed based on the bathtub water level detected by the sensor 8. The PQ data is stored in the PQ data storage unit 36.

  In the present embodiment, the automatic hot water filling means 33 normally has a water level of the bathtub 30 that is initially 5 cm higher than the reference water level that is defined at the upper end of the connection part of the recirculation circuit 31 to the side wall of the bathtub 30. A quantity of hot water or water is dropped into the bathtub 30, and then the circulating pump 9 is driven to confirm that the running water is detected by the running water detection sensor 11, and then the quantity of hot water or water up to the set water level is added to the bathtub 30. (In FIG. 1, the arrow from the automatic hot water filling means 33 to the circulation pump 9 is omitted). The method of automatic hot water filling is not particularly limited and is set as appropriate. The automatic hot water filling means 33 performs automatic hot water filling according to the set sequence program.

  The drain liquid amount detection means 2 detects the drain amount in the drain tank 13, and in this embodiment, drain liquid amount detection electrodes 2a, 2b, 2c (see FIG. 2) provided on the upper side of the drain tank 13. Connected).

  The capacity of the drain tank 13 is, for example, 3.5 liters. When the amount of drain stored in the drain tank 13 exceeds a predetermined drain storage lower limit (for example, 5% of the capacity of the drain tank 13), the drain tank 13 is drained. When the liquid amount detection electrode 2a detects the drain and reaches a predetermined drain drain reference amount (for example, 50% of the capacity of the drain tank 13), the drain liquid amount detection electrode 2b detects the drain, and the predetermined drain When the storage upper limit value (for example, 90% of the capacity of the drain tank 13) is reached, the drain liquid amount detection electrode 2c is configured to detect drain.

For example, if 60 MJ (input, 14.3 Gcal) is used for hot water in one day, (60 MJ / 4.2 / 25) × 0.95 (thermal efficiency) ≈543 (liters / 25 deg)
up), water having a feed water temperature of 15 ° C. is heated to 40 ° C., and 543 liters of hot water can be used. At this time, if the humidity is 100%, for example, 1.4 liters of drain is generated. Therefore, in the drain tank 13 having a capacity of 3.5 liters, the drain for two days can be stored under the above conditions. Also, if the humidity is low, the amount of drain generated is small, for example, it may be about half of that at 100% humidity. Therefore, if the humidity is low, the time for storing the drain further increases.

  The drain liquid amount detection means 2 detects the amount of drain water in the drain tank 13 based on the detection signals of the respective drain detection electrodes 2a, 2b, 2c, for example, a drain drainage standard in which the detected value is predetermined. When the amount is reached (when drain detection is performed by the drain detection electrode 2b in addition to drain detection by the drain detection electrode 2a), this detection signal is applied to the drain discharge control means 38.

  The remaining water presence / absence determination unit 35 operates the circulation pump 9 provided in the reheating circulation path 31 to detect the presence or absence of flowing water in the reheating circulation path 31, and when the flowing water is detected, there is remaining water in the bathtub 30. When the running water is not detected, it is determined that there is no remaining water in the bathtub 30. When the circulating pump 9 is operated, it can be determined that flowing water is detected by the flowing water detection sensor 11 and that there is no flowing water when no flowing water is detected. It may be determined that there is running water when the water level above the connection portion of 31 to the bathtub 30 is detected, and that no running water is detected when the water level is not detected. A determination signal for the presence or absence of residual water in the bathtub 30 is applied to the drain discharge control means 38.

  When the amount of drain stored in the drain tank 13 is equal to or greater than a predetermined drainage reference amount, the drain discharge control unit 38 determines that there is no residual water in the bathtub 30 by the residual water presence / absence determination unit 35. The drain is discharged to the bathtub 30 through the drain lead-out path 16 and the reheating circulation path 31.

  The present embodiment has the following configuration in order to drain the drain to the bathtub 30 through the recirculation circuit 31 under the control of the drain discharge control means 38. That is, as shown in FIG. 2, the suction side 24 of the circulation pump 9 has a return pipe 28 for introducing hot water from the bathtub 30 into the reheating circulation path 31, and the drain tank 13 to the reheating circulation path 31. The drain lead-out path 16 that guides the drain is connected to be switched by switching the three-way valve 21.

  When the drain discharge control means 38 does not perform drain discharge, the drain discharge valve 17 formed by an electromagnetic valve is closed, and the three-way valve 21 is operated to thereby operate the drain discharge path 16 and the circulation pump. 9 is connected to the suction side 24. In this manner, the recirculation operation can be performed by driving the circulation pump 9 in the same manner as in the conventional reheating operation.

  Further, the drain discharge control means 38 opens the drain outlet valve 17 and further operates the three-way valve 21 to connect the drain outlet path 16 and the suction side 24 of the circulation pump 9 during the drain discharge. In this state, the pump is driven by the circulation pump 9, and the drain is replenished through the drain lead-out path 16 to the circulation path 31, and the drain is discharged to the bathtub 30.

  In this embodiment, the drain is accurately discharged to the bathtub 30 through the recirculation circulation path by switching the connection between the drain lead-out path 16 and the suction side of the circulation pump 9 and driving the circulation pump 9 in this way. It is possible to perform drainage accurately.

  The drain discharge control means 38 stops drain discharge when the drain detection liquid amount becomes equal to or lower than the drain storage lower limit value or when a preset time has elapsed from this time. The circulation pump 9 is stopped before all the drain in the drain tank 13 is discharged so that the water seal is maintained (so that air does not enter the circulation pump 9).

  After the drain discharge control means 38 discharges the drain to the bathtub 30 through the recirculation circuit 31, the water supply control means 39 opens the hot water solenoid valve 27 and supplies a predetermined set amount of water (for example, 20 liters). Water is sent to the bathtub 30 through the recirculation circuit 31. Note that this water supply may be performed by operating the electromagnetic proportional valve 53 without heating the water from the water supply passage 46 or through the hot water supply heat exchangers 4 and 6.

  The water level comparing means 32 is predetermined by the automatic hot water filling means 33 when the automatic hot water filling means 33 fills the bathtub 30 after the drain discharge control means 38 discharges the drain. After the dropping of the hot water amount Q1 corresponding to the water level for detecting the remaining water (in this embodiment, the reference water level, P1 in FIG. 3) into the bathtub 30 (after the dropping is finished), the water level sensor A water level comparison operation is performed for comparing the detected bathtub water level detected by No. 8 with the bathtub water level of the PQ data corresponding to the amount of water dropped into the bathtub 26.

  In this embodiment, since the drain discharge control means 38 discharges the drain and then the water supply control means 39 supplies the water, the water level comparison means 32 matches this water supply quantity ΔQ with the water quantity Q. The water level corresponding to this water amount, that is, the water level P2 (P2 = P1 + ΔP) obtained by adding the water level ΔP corresponding to the water amount ΔQ to P1 shown in FIG. 3 and the detection bath water level of the water level sensor 8 are compared. This water level comparison result is added to the bathtub drainage notification means 34 and the automatic hot water filling stopping means 37.

  When the water level comparison means 32 determines that the detected bathtub water level is larger (higher) than the bathtub water level of the hot water filling data, the bathtub drainage notification means 34 issues a notification that prompts the discharge of hot water in the bathtub. . This notification method is not particularly limited and is set as appropriate. For example, a message with a content such as “please remove the bath cap and throw away the hot water” is transmitted from the speaker 77. Along with this message transmission, this content may be displayed on the display unit of the remote control device.

  When the water level comparison operation is performed by the water level comparison means 34, the automatic hot water filling stop means 37, when the detected bathtub water level is larger than the bathtub water level of the hot water filling data, Stop operation.

  The bath hot water supply apparatus of the present embodiment is configured as described above, and by draining drain appropriately to the bathtub 30 through the recirculation circuit 31, problems of laying costs of drain drain pipes, etc. The water level above the connection part of the recirculation circuit 31 (water level above the reference water level) has the advantage that it can also prevent problems of discomfort given to the user when liquid drainage is discharged as it is. When drain water is discharged in a state where there is residual water up to the water level below the reference water level, of course, it is possible to prevent drain from being mixed in the hot water of the bathtub. By urging to discharge the bath water containing the drain, it is possible to prevent the bath water containing the drain from being used.

  Next, a second embodiment of the bath water heater according to the present invention will be described. The second embodiment is configured in substantially the same manner as the first embodiment, and a duplicate description thereof is omitted.

  The second embodiment has the system configuration shown in FIG. 4 and omits the drain neutralization means 14 provided in the first embodiment. In the second embodiment, the bath bypass passage 22 that connects the return pipe 28 of the recirculation circuit 31 and the forward pipe 29 without passing through the reheating heat exchanger 12 is provided on the discharge side of the circulation pump 9. The drain led to the recirculation circuit 31 is discharged to the bathtub 30 through the bath bypass passage 22, the return pipe 28, and the forward pipe 29 without passing through the reheating heat exchanger 12. It is configured to do.

  In the second embodiment, a bypass electromagnetic valve 18 is provided in the bath bypass passage 22, and an electromagnetic valve 19 is provided in a pipe line between the flowing water detection sensor 11 and the reheating heat exchanger 12. 1 has a control configuration indicated by a solid line and a broken line.

  When the drain discharge is not performed, the drain discharge control means 38 closes the drain discharge valve 17 and disconnects the drain discharge path 16 and the suction side 24 of the circulation pump 9. At this time, the solenoid valve 18 is closed, the solenoid valve 19 is opened, and the three-way valve 21 is adjusted so that the return pipe 28 and the bypass passage 22 are not connected. In this manner, the recirculation operation can be performed by driving the circulation pump 9 in the same manner as in the conventional reheating operation.

  Further, the drain discharge control means 38 opens the drain outlet valve 17 during the drain discharge execution operation, connects the drain outlet path 16 and the suction side 24 of the circulation pump 9, closes the solenoid valve 19, and bypasses the bypass solenoid valve 18. Is opened, the three-way valve 21 is adjusted, and the return pipe 28 and the bypass passage 22 are connected. In this state, the drain is guided to the recirculation path 31 through the drain lead-out path 16 by driving the circulation pump 9.

  Instead of providing the bypass solenoid valve 18 and the solenoid valve 19, a three-way solenoid valve is provided at the position shown in FIG. 4A so as to switch between connection and disconnection of the return pipe 28 and the bypass passage 22. It may be. Alternatively, after the circulation pump 9 starts to be driven, the drain outlet valve 17 may be opened to connect the drain outlet path 16 and the suction side 24 of the circulating pump 9.

  The second embodiment is configured as described above, and the second embodiment can also achieve the same effect by substantially the same operation as the first embodiment.

  In the second embodiment, the drain guided to the recirculation circulation path 31 side during the drain discharge execution operation is passed through the bath bypass passage 22 and not to the recirculation heat exchanger 12 to the forward pipe 29 and the return pipe 28. Since it is introduced and discharged to the bathtub 30, even if the drain neutralization means 14 is omitted and the drain having high acidity is discharged without neutralization, the drain is discharged without passing through the reheating heat exchanger 12. Thus, corrosion of the reheating heat exchanger 12 generally formed of a metal containing copper can be prevented.

  In addition, for example, the recirculation circuit 31 that connects the bathtub 30 and the bath water heater (apparatus) is mostly formed of a non-metallic tube such as a cross-linked polyethylene tube in recent years. The pipes in the appliance can be protected from corrosion by acidic drain by plastic coating, but the heat exchanger cannot be coated. In addition, the unneutralized drain is heated to increase its corrosivity, and the heat exchanger is preheated (approximately the same as post-boiling) to increase the corrosion caused by the drain. If it is possible to prevent the unneutralized drain from passing through the soaking heat exchanger 12 alone, the effect of preventing corrosion and the like by the drain increases.

  Then, the neutral acid drain is neutralized without being neutralized, and is led to the recirculation circuit 31 and passed through the recirculation circuit 31, so that the recirculation circuit can be sterilized with drain having a high acidity.

  In addition, this invention is not limited to the said Example, Various aspects can be taken. For example, in each of the above embodiments, the latent heat recovery heat exchanger 6 does not include the fins 3. However, as in the bath water heater shown in FIG. 3 may be adopted. Further, the bath hot water supply device may perform combustion control of the hot water supply burner 1 using the incoming water temperature obtained by calculation or the like instead of providing the incoming water thermistor.

  In each of the above embodiments, the drain liquid amount detection electrodes 2a, 2b, 2c are connected to the drain liquid amount detection means 2 to detect the drain liquid amount. The configuration for detecting the amount of liquid is not particularly limited, and is appropriately set.

  Further, in the first embodiment, the drain neutralization means 14 is provided on the upper side of the drain tank 13 separately from the drain tank 13, but the drain neutralization means 14 can also be provided in the drain tank 13. Moreover, the detailed structure of the drain neutralization means 14 is set suitably.

  Further, in each of the above embodiments, the water level for residual water detection for comparison by the water level comparison means 32 is set as the reference water level, but the water level for residual water detection is not necessarily the reference water level and is set as appropriate. For example, it is set to an appropriate value lower than the set water level of the hot water filling.

  Furthermore, in each of the above-described embodiments, the water supply control means 39 is provided, and after draining the drain into the bathtub 30, the water supplied from the water supply source is led from the pouring connection path 26 to the recirculation circuit 31, and the bathtub 30. However, this water supply may be performed while draining the water to the bathtub 30. Further, the water supply control means 39 can be omitted. In this case, the water level comparing means 32 detects the detected bathtub water level and the bathtub 30 detected by the water level sensor 8 after the amount of hot water corresponding to a predetermined remaining water detection water level has been dropped into the bathtub 30, for example. The water level of the PQ data corresponding to the amount of water dropped in is compared with the bathtub water level.

  In addition, when the recirculation circuit 31 between the bath water heater and the bathtub is formed using a resin such as crosslinked polyethylene as recently, there is a problem even if acidic drain remains in the recirculation circuit 31. However, the recirculation circuit 31 between the bath water heater and the bathtub is formed using a copper pipe until recently, and this pipe is located under the floor or behind the wall. In many cases, it is difficult to replace this pipe line. Therefore, even when the bath water heater is replaced by replacement, usually, the recirculation circuit 31 between the bath water heater and the bathtub is not replaced, and a resin coating is added to the pipeline. Difficult to do. In such a case, in order to prevent the recirculation circuit 31 between the bath water heater and the bathtub from being corroded by acidic drain, in particular, when draining to the recirculation circuit 31 without neutralizing the drain. The water supply control means 39 should be provided as in the above embodiments.

  In addition, the water supply control means 39 is provided, and after draining the drain into the bathtub 30, the water supplied from the water supply source is replenished from the pouring connection path 26 to the recirculation path 31 and supplied to the bathtub 30. When provided, since there is almost no damage to the reheating heat exchanger 12 due to the drain, the three-way valve 21 may be omitted, and the drain may be discharged using both the outgoing pipe 29 and the return pipe 28.

  Further, in each of the above embodiments, the hot water supply burner 1 has three hot water supply burners 1a, 1b, and 1c, and the reheating burner 7 has two burners 7a and 7b. The detailed configuration of 7 and the details of the piping configuration are not necessarily limited to the configuration shown in FIG.

  Furthermore, the bath hot water supply apparatus of the present invention may be an apparatus having a heating function, for example, other than hot water supply and bathing. In this case, it is good also as a structure which provides the burner for heating other than the hot water supply burner 1 and the reheating burner 7, and for heating for exhibiting a heating function, without providing the reheating burner provided in each said Example. A burner is provided, and the reheating heat exchanger 12 may be a type of heat exchanger that performs heat exchange between hot water heated by the heating burner and water passing through the reheating circulation path 31.

  Furthermore, in any of the above explanations, the drain discharge execution operation by the drain discharge control means 38 leads the drain to the recirculation path 31 through the drain lead-out path 16 and discharges it to the bathtub 30 through the recirculation path 31. For example, as shown by a broken line in FIG. 4, a drainage passage 66 communicating with the outgoing pipe 29 of the recirculation circulation path 31 via the three-way solenoid valve 65 is provided, and the drain is replenished with the recirculation circulation path 31. It may be led to the drainage passage 66 and drained into the bathroom.

  Furthermore, although the gas combustion type bath water heater is used in the above embodiment, the bath water heater may be an oil combustion type bath water heater.

DESCRIPTION OF SYMBOLS 1 Hot water supply burner 2 Drain liquid amount detection means 4 Main hot water supply heat exchanger 5,10 Combustion fan 6 Hot water supply heat exchanger for latent heat recovery 7 Reheating burner 8 Water level sensor 9 Circulation pump 11 Flowing water detection sensor 12 Reheating heat exchanger 13 Drain tank 14 Drain neutralization means 16 Drain lead-out path 17 Drain lead-out valve 18 Bypass solenoid valve 22 Bypass passage 23 Controller 30 Bath 31 Reheating circulation path 32 Water level comparison means 33 Automatic hot water filling means 34 Bath drainage notifying means 35 Existence of remaining water Judgment part 36 PQ data storage part 37 Automatic filling stop means 38 Drain discharge control means 39 Water supply control means

Claims (5)

  A hot-water supply burner, a main hot-water supply heat exchanger that absorbs sensible heat in the combustion gas of the hot-water supply burner, and an exhaust latent heat that is disposed downstream of the main hot-water supply heat exchanger in the flow of the combustion gas A latent heat recovery hot water supply heat exchanger, a hot water supply passage connected to the outlet side of the main hot water supply heat exchanger, and a recirculation circuit connected to the side wall of the bathtub. A circulation pump is provided in the circulation path, and the reheating circulation path is connected to the hot water supply passage through a pouring connection path, and the latent heat recovery hot water supply heat exchanger and the main hot water supply heat exchanger are connected to each other. Automatic hot water filling means for feeding hot water heated by passing through the pouring connection path and the recirculation circulation path to the bathtub and filling the bathtub, bathtub water level detection means for detecting the bathtub water level, and bathtub A flow rate detection means for detecting the amount of hot water filling The automatic hot water filling means is detected by the hot water filling data indicating the relationship between the bathtub water level and the hot water amount, the amount of hot water detected by the flow rate detecting means, and the bathtub water level detecting means. A bath water heater having a configuration for performing hot water filling to the bathtub based on the bath water level, drain recovery means for recovering drain generated in the hot water heat exchanger for latent heat recovery, and the drain recovery means A drain storage means for storing the drain collected by the drain, a drain lead-out path for guiding the drain stored in the drain storage means to a pipe line between the bathtub of the recirculation circulation path and the suction side of the circulation pump, and the drain storage When the amount of drain stored in the means is equal to or greater than a predetermined drainage reference amount, the circulation pump is driven to drain the drain through the drain lead-out path and the recirculation circuit. A drain discharge control means, and when the automatic hot water filling means performs the hot water filling to the bathtub after the drain discharge by the drain discharge control means, the bathtub is empty in the bathtub. After the completion of dropping into the bathtub, the water level of the hot water corresponding to a predetermined water level for detecting residual water that can be detected by the bathtub water level detecting means when the hot water is dropped is detected by the bathtub water level detecting means. A water level comparison means for performing a water level comparison operation for comparing the detection water level of the hot water filling bath corresponding to the dropped water amount corresponding to the water level for detecting the residual water, When it is determined by the means that the value of the detected bathtub water level is larger than the value of the bathtub water level of the hot water filling data, a notification is made to prompt the discharge of hot water in the bathtub. A bath hot water supply device characterized by having bath drainage notification means.   A drainage passage is connected via a three-way solenoid valve to the outgoing pipe of the pipeline from the reheating heat exchanger to the bathtub, and flows from the circulation pump side to the bathtub side through the outgoing pipe. 2. The bath hot water supply apparatus according to claim 1, further comprising a structure in which a flow path of the drain is switched to the drainage passage by the three-way solenoid valve and the drain is discharged into the bathroom through the drainage passage.   The bath water heater according to claim 1 or 2, wherein the water level for detecting the residual water is a reference water level determined at an upper end portion of a connection part of the recirculation circuit to the side wall of the bathtub.   When the water level comparison operation is performed by the water level comparison means, if the detected bathtub water level value is larger than the bathtub water level value in the hot water filling data, the automatic hot water filling means stops the automatic hot water filling operation. The bath hot-water supply apparatus according to claim 1, 2 or 3, further comprising means.   The drain discharge control means has a water supply control means for supplying a predetermined set amount of water to the bathtub through the reheating circulation path after or after discharging the drain through the recirculation circulation path. After the end of the water supply by the water level, the water level is detected by the bathtub water level detection means detected by the bathtub water level detection means and the bath water level of the hot water filling data corresponding to the amount of water set by the amount of water dropped into the bathtub by the automatic hot water filling means The bath hot water supply apparatus according to any one of claims 1 to 4, wherein the comparison means compares.

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