JP2008215754A - Heating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heating system for effectively using the remaining heat of bathtub water while suppressing the occurrence of operating noises. <P>SOLUTION: When reservation of heating operation is set within ten hours after finishing the operation of a bath for bathing (S1), a bath pump and a heating pump are operated (S5, S7), and a bath thermomotive valve is opened to heat heating side hot water in a bath heater (S9-S13) with the remaining heat of bathtub water, on condition that a temperature difference of 15°C or higher exists between bathtub water on the bath side and hot water on the heating side (YES in S9). When thirty minutes pass or the temperature of the bathtub water becomes lower until the temperature difference is lower than 8°C (YES in S12, YES in S11), exhaust heat utilizing operation is stopped to start heating operation. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heating system that circulates and supplies hot water as a heating heat source to a heating terminal and radiates the warm water at the heating terminal, and in particular, exhaust heat from hot water remaining in a bathtub after bathing is one of the heating sources. Related to the technology to be used as one.

  Conventionally, as a heating system, a liquid-liquid heat exchanger is interposed in a heating-side circulation circuit that circulates hot water of a heating heat source, and hot water in a bathtub (hereinafter referred to as “bath water”) with respect to the liquid-liquid heat exchanger. ) Is made to pass through the circulatory side circulation circuit that can be circulated, and the bath water is heated by the hot water of the heating heat source. And in this thing, if the temperature of the bathtub water detected by the temperature detection sensor of the bath side circulation circuit is more than a certain temperature, the bath water is circulated in the liquid-liquid heat exchanger by forced circulation by the bath side circulation pump. On the other hand, by operating the heating side circulation pump and passing the hot water of the heating heat source through the liquid-liquid heat exchanger, the residual heat of the bathtub water is recovered, and the hot water after the recovery of the residual heat is used for heating to the low-temperature heating terminal A heat source that is circulated and supplied is known (for example, see Patent Document 1). In short, using the configuration in which the bathtub water is heated by the warm water on the heating side, the warm water on the heating side is heated by the remaining hot water of the bathtub water.

JP-A-8-35675

  However, in recovering the residual heat of the bathtub water disclosed in the above-mentioned Patent Document 1, in order to determine whether the residual heat of the bathtub water (residual hot water) can be recovered (detection / determination that there is a certain temperature or more), Although it is conceivable to provide a temperature detection sensor on the inside of the bathtub and directly detect it, this is not realistic. In other words, in order to newly install a temperature detection sensor, not only the sensor itself, but also the signal line needs to be extended from the bathtub to the controller in the heat source unit, resulting in an increase in cost and the need to newly manufacture the bathtub in which the sensor is provided. Because it becomes. For this reason, the temperature detection sensor originally provided on the bath side circulation circuit is utilized, but in order to detect the temperature by the temperature detection sensor, the bath side circulation pump is operated to supply the bath water. It is necessary to circulate through the bath-side circulation circuit, which causes operating noise of the bath-side circulation pump.

  In addition, there are various problems to be overcome in relation to the actual heating system or in addition to the bath system in order to effectively use the residual heat from the bath water that will be dissipated wastefully after bathing. is there.

  This invention is made | formed in view of such a situation, The place made into the objective provides the heating system which can aim at the effective utilization of the residual heat of bathtub water, suppressing generation | occurrence | production of an operating noise. There is.

  In order to achieve the above object, in the present invention, a heating terminal, a bathtub, and a heat source machine, and as this heat source machine, a heating side circulation circuit that circulates and supplies hot water as a heating heat source to the heating terminal, A heating system comprising: a bath-side circulation circuit that circulates bathtub water in the bathtub; and a heat exchanger through which the bath water of the bath-side circulation circuit and the hot water of the heating-side circulation circuit pass in a heat-exchangeable manner. The following specific items were prepared for the target. That is, it comprises exhaust heat utilization control means for performing exhaust heat utilization operation for utilizing the exhaust heat of the residual water in the bathtub as a heat source for preheating warm water in the heating-side circulation circuit, and the exhaust heat utilization control means When a heating operation execution reservation command for circulatingly supplying hot water to the heating terminal is input and set, the first set time after the previous bath operation including heating operation for bathing in the bathtub ends. On the condition that it is within the time range before the elapse of time, the bath water of the bath side circulation circuit and the hot water of the heating side circulation circuit are respectively passed through the heat exchanger before the start of the heating operation. The exhaust heat utilization operation is performed (claim 1).

  In the case of the present invention, it becomes possible to execute the exhaust heat utilization operation by the situation determination based on the elapsed time, and there is no need to detect and determine the temperature situation of the bath water or hot water. As a result, circulation for detecting the temperature situation Generation of operating noises such as pumps can be avoided. That is, before the first set time elapses, since the bathtub water remaining in the bathtub at the time of the previous bathing is maintained at a relatively high temperature, the waste heat is used as a heat source for preheating the hot water. By executing the use operation, it becomes possible to effectively recover and use the exhaust heat of the bathtub water. Thereby, effective use of the residual heat of bathtub water can be achieved, suppressing generation | occurrence | production of an operating noise.

  The exhaust heat utilization control means of the present invention can be configured to execute the exhaust heat utilization operation in a time range of a second set time before the start of the heating operation (Claim 2). By doing so, it becomes possible to continue the heating operation using the hot water preheated based on the recovery of the waste water from the bathtub water, and the fuel required for the combustion in the heating operation with the most efficient use of heat. Consumption can be reduced.

  Further, the exhaust heat utilization control means can be configured to execute the exhaust heat utilization operation on condition that a time equal to or longer than the third set time has elapsed since the end of the previous heating operation. Item 3). By doing in this way, it becomes possible to ensure that the hot water which is the object of preheating is lowered to a temperature lower than the predetermined temperature, and to recover the exhaust heat from the bath water.

  Further, the exhaust heat utilization control means can be configured to stop the exhaust heat utilization operation when a start request for a bath operation including a bath water heating operation occurs during execution of the exhaust heat utilization operation. (Claim 4). By doing so, priority is given to the user's intended use, which is convenient for the user.

  Furthermore, a bath water temperature detection sensor for detecting the temperature of the bath water in the bath side circulation circuit and a hot water temperature detection sensor for detecting the temperature of the hot water in the heating side circulation circuit are provided, and as exhaust heat utilization control means, The exhaust heat utilization operation can be configured on the condition that the detected temperature of the bath water has a temperature difference greater than the required set temperature difference than the detected temperature of the hot water (Claim 5). By doing in this way, the condition based on the temperature difference is added to the condition based on the time situation, and the exhaust heat utilization can be performed more reliably.

  On the other hand, as a second invention, a heating terminal, a bathtub, and a heat source machine are provided, and the heat source machine circulates and supplies hot water as a heating heat source to the heating terminal, For a heating system comprising a bath-side circulation circuit for circulating bath water, and a heat exchanger through which the bath water of the bath-side circulation circuit and hot water of the heating-side circulation circuit are passed in a heat-exchangeable manner, Bathtub water temperature detection sensor for detecting the temperature of the bath water in the bath side circulation circuit, the hot water temperature detection sensor for detecting the temperature of the hot water in the heating side circulation circuit, and the exhaust heat of the remaining water in the bathtub are circulated on the heating side An exhaust heat utilization control means for executing an exhaust heat utilization operation for use as a heat source for preheating warm water in a circuit is provided. And when the execution reservation instruction | command of the heating operation which circulates and supplies warm water to the said heating terminal is input as the said waste heat utilization control means, the detection temperature of the bathtub water output from the said bathtub water temperature detection sensor is warm water. On the condition that the temperature difference is more than the required set temperature difference than the detection temperature of the hot water output from the temperature detection sensor, the bath water and the heating side The warm water in the circulation circuit is passed through the heat exchanger, and the exhaust heat utilization operation is performed (claim 6).

  In the case of this 2nd invention, when using the exhaust heat of bathtub water by the conditions based on a temperature difference, in the state which the bathtub water can collect | recover exhaust heat reliably, it can preheat warm water It is possible to start execution of the exhaust heat utilization operation after confirming this. As a result, it is possible to realize exhaust heat recovery and exhaust heat utilization that are surely effective in the exhaust heat utilization operation.

  As described above, according to any one of the heating systems according to claims 1 to 5, the exhaust heat utilization operation can be executed by the situation determination based on the elapsed time, and before the first set time elapses. If this is the case, since the bathtub water remaining in the bathtub at the time of the previous bathing stays at a relatively high temperature, the exhaust heat of the bathtub water is obtained by performing the exhaust heat utilization operation using the bathtub water as a heat source for preheating the hot water. Can be collected and used effectively. This eliminates the need for detection and determination of the temperature status of bath water and hot water. As a result, it is possible to effectively use the residual heat of the bath water while avoiding the generation of operating noise such as a circulation pump for detecting the temperature status. Will be able to plan.

  In particular, according to claim 2, the heating operation can be continuously started using the hot water preheated based on the exhaust heat recovery of the bath water, and the fuel required for the combustion in the heating operation with the most efficient use of heat. Consumption can be reduced.

  According to the third aspect, the exhaust heat utilization operation can be executed when the hot water to be preheated is reliably lowered to a temperature lower than the predetermined temperature, thereby recovering the exhaust heat from the bath water. It can be ensured.

  According to the fourth aspect of the present invention, the exhaust heat utilization operation is stopped when a bath operation start request is generated, so that the user's intention to use the bath is prioritized, which is convenient for the user.

  Furthermore, according to the fifth aspect, the exhaust heat utilization can be performed more reliably by adding the condition based on the temperature difference to the condition based on the time situation.

  On the other hand, according to the heating system of claim 6, the hot water is preheated in a state where the exhaust water of the bathtub water can be reliably recovered by using the exhaust heat of the bathtub water according to the condition based on the temperature difference. After confirming that it is possible, the execution of the exhaust heat utilization operation can be started. As a result, exhaust heat recovery and exhaust heat utilization that are effectively effective in the exhaust heat utilization operation can be realized.

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

<First Embodiment>
FIG. 1 shows an example of a heating system according to the first embodiment of the present invention. This heating system 1 exemplifies a system using a combined heat source unit 2 having both of a hot water circulation heating function, a hot water supply function, and a bathing function, and from a combustion exhaust gas in a combustion heating type heating unit The latent heat recovery type which improves the efficiency by performing the latent heat recovery is illustrated. In carrying out the present invention, it is a composite heat source that has at least a hot water circulation heating function and a bathing function, and exchanges heat between the hot water of the heating heat source and the remaining water in the bathtub B. The hot water supply function is not essential, and it is not necessary to be a latent heat recovery type.

  In the figure, reference numeral 21 is a hot water supply circuit for realizing a hot water supply function, 22 is a heating circuit that is a heating side circulation circuit for realizing a hot water circulation heating function, and 23 is a bathroom for realizing a bath reheating function. A recirculation circuit that is a side circulation circuit, 24 is a pouring circuit for pouring hot water, 25 and 26 are secondary heat exchangers for recovering latent heat from combustion exhaust gas, and 27 is this secondary heat exchanger 25. , 26 is an exhaust gas drain processing circuit for processing the exhaust gas drain generated at 26, and 28 is a controller for controlling the operation of each of these circuits. The hot water reheating in the composite heat source 2 is of a type in which the hot water of the heating circuit 22 is used as a heat source and the bath water of the reheating circuit 23 is heated by liquid-liquid heat exchange heating to perform reheating. It is.

(Hot water supply circuit 21)
The hot water supply circuit 21 includes a hot water supply combustion burner 31, a hot water supply primary heat exchanger 32 that heats and heats incoming water by the combustion heat of the combustion burner 31, and a fuel supply system 33 that supplies fuel gas to the combustion burner 31. And an inlet channel 34 for allowing tap water or the like to enter the inlet side of the primary heat exchanger 32 for hot water supply, and an outlet channel 35 for discharging the hot water heated by the primary heat exchanger 32. Before entering the primary heat exchanger 32, the incoming water from the water inlet 34 is passed through a heat exchange section for hot water supply of the secondary heat exchanger 25, and this secondary heat exchanger 25. In FIG. 1, water is introduced into the primary heat exchanger 32 in a state preheated by recovering the latent heat of the combustion exhaust gas.

  The fuel supply system 33 also serves as a fuel supply to a heating combustion burner 51, which will be described later, and the fuel gas supply amount to the original solenoid valve 36, the hot water supply combustion burner 31 and the heating combustion burner 51 is changed and adjusted individually. An electromagnetic proportional valve for hot water supply and an electromagnetic proportional valve for heating are provided.

  Then, water such as tap water supplied to the water supply connection port 341 is introduced through the inlet channel 34, and this incoming water is first preheated by the secondary heat exchanger 25, and further passes through the primary heat exchanger 32 for hot water supply. The hot water heated up to a predetermined temperature and discharged into the hot water outlet 35 through the hot water supply port is supplied to a predetermined hot water supply location such as the curan 40 of the kitchen or the pouring circuit 24 via the hot water connection port 351. (Pouring hot water). The hot water supply control in the hot water supply circuit 21 is performed based on the setting input of the set hot water supply temperature from the remote controller 281 and the detected values from the incoming water flow rate sensor 41, the incoming water thermistor 42, the outgoing hot water thermistor 43 and the like in the controller 28. The hot water supply temperature to the currant 40 is executed so as to become the set hot water supply temperature.

(Heating circuit 22)
The heating circuit 22 includes a heating combustion burner 51, a heating primary heat exchanger 52 that heats and heats the circulating hot water using the combustion heat of the combustion burner 51, and heating hot water that passes through the heating primary heat exchanger 52. And a circulation path 53.

  The hot water circulation path 53 includes a heating return path 63 that sends low temperature water returned to the expansion tank 61 and stored to the inlet of the heating primary heat exchanger 52 by the operation of the heating circulation pump 62, and the heating primary path. A high-temperature forward path 65 from the outlet of the heat exchanger 52 to the high-temperature forward connection port 64; a low-temperature forward path 67 that branches from the heating return path 63 at a downstream position of the circulation pump 62 and reaches the low-temperature forward connection port 66; A bus heater circulation path 68 that branches from the high-temperature forward path 65 and passes through a liquid-liquid heat exchanger (bus heater) 81 (described later) in the middle and then joins a return path 71 (described later) through a warm valve 82 as an open / close switching valve. A bypass path 69 for branching from the high temperature outgoing path 65 upstream of the high temperature outgoing connection port 64 to return the hot water to the expansion tank 61, and the return header 73 and the return connection port 7 from the heating terminals 72, 75. And a return passage 71 to flow into the bypass passage 69 after preheated by latent heat recovery from the flue gas through the low temperature of the return hot water returned to first in the secondary heat exchanger 26.

  Briefly describing the supply of hot water at two temperatures in the hot water circulation path 53, high-temperature water having a predetermined temperature (for example, 80 ° C.) heated by the primary heat exchanger 52 for heating is supplied from the high-temperature forward path 65 to the high-temperature forward connection port. 64 and a high-temperature forward header 78, for example, are supplied to a high-temperature heating terminal 72 such as a bathroom dryer, and hot water having a low temperature due to heat dissipation is returned to the return path 71 from the return header 73 and the return connection port 70, After being preheated by the heat exchanger 26, it is returned to the expansion tank 61 through the bypass 69. A part of the high temperature water is also returned to the expansion tank 61 through a bypass path 69 branched from the high temperature outgoing path 65, and becomes a low temperature water having a predetermined temperature (for example, 60 ° C.) by mixing with the high temperature water. A part of the low-temperature water is sent to the heating primary heat exchanger 52 through the heating return path 63 and heated to generate the high-temperature water, while the other part is connected to the low-temperature forward connection port 66 from the low-temperature forward path 67. And it is supplied to a low-temperature heating terminal 75 such as a floor heater in each room through a low-temperature going-out header 74 with a thermal valve. In addition, although the heating terminals 72 and 75 are shown here one by one, the present invention is not limited to this. Usually, there are a plurality of predetermined high temperature headers 78 and low temperature headers 74 that are connected to each other so as to be distributed individually. There are a predetermined number, and the return header 73 has a connection port for receiving the return hot water from all of the heating terminals.

  The low-temperature going-out header 74 supplies the low-temperature water to the corresponding heating terminal 75 by switching the open and closed terminal thermal valves individually by the controller 28 described later when the low-temperature terminal 75 for heating is started. . Then, the hot water radiated at each heating terminal 75 and further cooled is returned to the return path 71 from the return header 73 and the return connection port 70 in the same manner as in the case of the high-temperature water after the heat radiation, and finally expanded. Returned to the tank 61. When reheating by the reheating circuit 23 described later is executed, the hot water from the heating primary heat exchanger 52 is branched from the high temperature outgoing path 65 by controlling the opening of the bath heat valve 82. The water flows into the bath heater circulation path 68 and is heated to a low temperature by subjecting the bath water to liquid-liquid heat exchange heating in the bath heater 81 serving as a heat exchanger, and is returned to the return path 71 to be finally passed through the secondary heat exchanger 26. Will be returned to the expansion tank 61. In short, high-temperature water is circulated and supplied to the bath heater 81 as a heat source for reheating.

  In the hot water circulation of the above two temperatures of the high temperature water and the low temperature water, the temperature control on the high temperature side of the heating is performed based on the temperature detected by the high temperature thermistor 76 disposed at the outlet of the primary heat exchanger 52 for heating. The combustion control of the combustion burner 51 is performed by the controller 28 so as to be supplied from the primary heat exchanger 52 for heating, and the temperature control on the low temperature side of the heating is performed as a hot water temperature detection sensor disposed in the expansion tank 61, and the low temperature thermistor 77. The same control is performed so that low temperature water having a predetermined temperature is supplied based on the detected temperature.

  In the expansion tank 61, the controller 24 automatically controls water injection and replenishment from the water inlet side of the hot water supply circuit 21 to drain excess water. .

(Turning circuit 23)
The reheating circuit 23 includes a bath heater 81 as a liquid-liquid heat exchanger for reheating (for bath water heating), a reheating circulation path 83 passing through the bath heater 81, and a recirculation circuit 83 through the reheating circulation path 83. A recirculation circulation pump 84 is provided as a bath-side circulation pump for forcibly circulating hot water. Then, when the recirculation pump 84 is turned on, the bathtub water taken out from the bathtub B is sent from the return connection port 831 to the bath heater 81 via the return path 83a, and the bath heater 81 is connected to the heating circuit 22 side. The bathtub hot water after being reheated by liquid-liquid heat exchange using high-temperature water as a heat source is sent from the outgoing path 83b to the bathtub B via the outgoing connection port 832. Further, a recirculation circuit 83 on the discharge side of the circulation pump 84 has a bathtub water thermistor 85 as a bathtub water temperature detection sensor, a water flow switch 86 that outputs a detection of flowing water by passing the flowing water, and a pressure detection type. The water level sensor 87 is provided.

(Pouring circuit 24)
The pouring circuit 24 includes a pouring path 88 that has an upstream end branched from the hot water supply circuit 21 and a downstream end joined to the recirculation circuit 83, and a pouring solenoid valve that switches between running and shutting of pouring by opening and closing switching. 89. The pouring electromagnetic valve 89 is controlled to be opened and closed by the controller 28 so that a predetermined amount of hot water is poured into the bathtub B through the pouring passage 35, the recirculation circulation passage 83, and the like.

(Exhaust gas drain processing circuit 27)
The exhaust gas drain treatment circuit 27 drains the exhaust gas drain generated by cooling and condensing the combustion exhaust gas by heat exchange for latent heat recovery in the secondary heat exchangers 25 and 26 after neutralization. It is a circuit installed in. That is, the exhaust gas drain treatment circuit 27 guides the exhaust gas drain collected and collected by the drain receiving portion disposed at the lower position of the secondary heat exchangers 25 and 26 to the drain treatment tank 272 through the drain introduction pipe 271. The drain tank 272 is neutralized and then drained out of the machine.

(Controller 28)
The controller 28 receives various operation commands based on an input operation by a user or the like from the remote controller 281 and controls the operation of each of the circuits 21, 22, 23, and 24. The controller 28 includes a microcomputer, a memory, and the like. It is a thing. The controller 28 includes hot water supply control means for controlling the hot water supply operation corresponding to each of the circuits 21, 22, 23, 24, reheating control means for controlling the reheating operation, and heating control for controlling the heating operation. In addition to providing the means as a basic part, in particular, there is provided exhaust heat utilization control means 282 (see FIG. 2) for controlling the operation of exhaust heat utilization operation.

  The composite heat source device 2 is provided with a dip switch 283 (see FIG. 2) as a setting switching means, and by using this dip switch manual switching operation, the exhaust heat utilization operation is enabled at the time of installation of the device (dip switch ON). Or set invalid (same as OFF) by the installation operator or the user. If the DIP switch is set to ON (selection setting for exhaust heat utilization operation control), the exhaust heat utilization control means 282 installed in the controller 28 functions effectively, and the user heats the remote controller 281. When performing the operation reservation operation, it is displayed that the exhaust heat utilization operation control is set by default to be executed prior to the heating operation. Even if the DIP switch is set to ON, the exhaust heat utilization operation control set as default can be switched OFF by manual operation on the remote controller 281. Hereinafter, the description will be made on the assumption that the dip switch 283 is turned on to perform the exhaust heat utilization operation control and the remote controller 281 is not switched to the user with the default setting as it is.

  The exhaust heat utilization operation control by the exhaust heat utilization operation control means 282 is executed in advance before a predetermined time before starting the heating operation when a predetermined condition (condition for determining whether to allow use of bathtub exhaust heat is satisfied). The hot water in the heating circuit 22 before the heating operation is preheated before the heating operation is started by collecting the exhaust heat of the bathtub residual water. In short, the heat of the hot water (tub residual water) remaining in the bathtub B after bathing is exhausted by natural heat dissipation as it is in the prior art, and the bath heater 81 described above before the bath water temperature decreases due to the natural heat dissipation. In this case, the exhaust heat is recovered and the hot water as a heating heat source is preheated to raise the temperature as much as possible. Hereinafter, a specific description will be given with reference to FIG.

That is, first, the exhaust heat utilization operation control after step S2 is executed when the permission condition is satisfied in the bathtub exhaust heat utilization operation permission determination (step S1).
If the bath exhaust heat utilization operation execution permission determination is described earlier with reference to FIG. 4, it is assumed that the dip switch 283 is ON (exhaust heat utilization operation control is effectively set) (YES in step SA1). The remote controller 281 also confirms that the exhaust heat utilization operation control is set to be valid and the switch setting operation is not invalidally performed by the user (YES in step SA2). Next, in steps SA3 to SA7 Judgment is made for each permission condition.

  It is determined whether or not the start flag of the exhaust heat utilization operation control is ON, that is, whether or not a heating reservation (particularly execution reservation for floor heating, which is a low-temperature heating terminal) is performed using the heating switch of the remote controller 281. (Step SA3). If a reservation for starting the heating operation is input to the remote controller 281 together with the heating operation start time, the start flag is turned ON in response to the input setting signal, and the start flag is turned ON or OFF. Whether or not a heating reservation has been made is determined. Only when the heating reservation is made, the exhaust heat utilization operation control is executed, and the permission condition is that the heating reservation is made.

  If the start flag is ON (YES in step SA3), then the first set time (for example, 10 hours) after the bath operation (the bath-side operation for bathing such as pouring and chasing) is completed. ) Before the elapse of time (within the first set time range) (step SA4). This is because the exhaust heat of the residual water in the bathtub also advances as natural heat radiation progresses over time, so that the amount of heat that can be recovered no longer remains and the exhaust heat cannot be used. Is determined by the elapsed time after the end of the bathing operation (whether or not the first set time has elapsed). What is necessary is just to set the elapsed time which can maintain the range of about 30 degreeC or more although the temperature of the bathtub residual water falls from the original 40 degreeC, for example, when this 1st setting time leaves it with a lid on the bathtub. If bathtub water is about 30 degreeC, the temperature difference of 15 degreeC will be ensured between the hot water of the heating circuit 22 side, for example, 15 degreeC, and the waste heat recovery from bathtub water can be performed effectively. In addition, the above-mentioned bathing operation does not include additional water treatment when checking the presence or absence of residual water in the bathtub.

  If it is within the first set time range (YES in step SA4), the third set time (for example, 4 hours) or more has elapsed since the completion of the combustion for the previous heating operation (combustion of the first combustion burner 51). Is determined (step SA5). Even after the heating operation is finished after combustion, the hot water in the heating circuit 22 is in a higher temperature than the bath water until the temperature is lowered due to natural heat radiation. Contrary to heat utilization, the result is that the heat of the hot water is wasted in the bathtub water as in the case of the original reheating operation. For this reason, it is the third set time from the end of combustion in the previous heating operation that the temperature of the hot water has decreased to such an extent that heat can be recovered from the residual water of the bathtub so that the hot water can be effectively preheated by using exhaust heat. The determination is made when the above time has elapsed. The third set time is set shorter than the first set time.

If the time equal to or longer than the third set time has elapsed (YES in step SA5), the latest history is that the bath circulation determination process is “NG” (No Good) (that is, the determination result that there is no bathtub residual water). Is not stored (step SA6). The bath circulation determination process determines whether the bathtub B has a predetermined amount or more of the remaining water in the bathtub B based on whether or not the water flow switch 86 is turned on (water flow detection) by operating the recirculation circulation pump 84. It is. This confirms the presence of the bathtub residual water.
If there is bathtub residual water (YES in step SA6), the reverse heat exchange determination process is “NG” (there is a temperature difference between the bathtub water and the hot water so that exhaust heat can be recovered from the bathtub water). It is determined whether or not the determination result that the condition is not satisfied is stored as the latest history (step SA7). In short, it is determined whether or not the determination result based on the previous temperature difference determination is “NG”.

  If there is no history that there is no temperature difference (YES in step SA7), the execution of the bath water waste heat utilization operation is permitted (step SA8), and the processing after step S2 in FIG. 3 is executed. On the other hand, if any one of the above-described determinations of step SA3 to step SA7 is not satisfied (NO in any of step SA3 to step SA7), the execution of the exhaust heat utilization operation is not permitted (prohibited) (step) SA9), the determination process from step SA1 is repeated.

  Returning to FIG. 3, when the exhaust heat utilization operation is permitted, an open command signal is output to the terminal thermal valve corresponding to the heating terminal 75 that circulates and supplies hot water (the terminal thermal valve of the low temperature side header 74). Then, a timer for the open conversion time (for example, 2 minutes) is started (step S2), and the passage of the time is waited (NO in step S3). If the time has elapsed (YES in step S3), it is checked whether or not the water flow switch 86 is normal (step S4). If normal, the reheating pump 84 is turned on (operated) (step) YES in S4, step S5). If the water flow switch 86 is ON (water flow detection) even though the water flow switch 86 is OFF (non-operating), for example, it is determined that there is an abnormal state such as a failure. Subsequent processing is stopped (NO in step S4, step S15).

  If the water flow switch 86 is not turned on even if the recirculation circulation pump 84 is turned on, it is determined that there is no predetermined amount of remaining water in the bathtub B (circulation judgment NG) (NO in step S6), and the subsequent processing is performed. At the same time, the history of circulation determination “NG” is stored (step S16). If the recirculation circulation pump 84 is turned on and the water flow switch 86 is turned on, it is determined that there is a predetermined amount of residual water in the bathtub B (circulation determination OK) (YES in step S6), and the heating circulation pump 62 is turned on ( (Step S7), and the bath water is circulated between the bath heater 81 and the bath B. Then, after waiting for a predetermined forced circulation time (time required for the bath water to circulate sufficiently) from the circulation determination “OK” (YES in step S8), the temperature difference determination in steps S9 to S13 is performed. A process of executing the exhaust heat utilization operation is performed while performing (reverse heat exchange determination).

  In the temperature difference determination, the temperature value of the bath water thermistor 85 (the bath water temperature; the return temperature) is a temperature value obtained by adding a necessary set temperature difference (for example, a temperature difference of 15 ° C.) to the temperature value detected by the low temperature thermistor 77. If it is equal to or higher than that (YES in step S9), it is determined that there is a temperature difference (exhaust heat that can be recovered) necessary for the exhaust heat utilization operation. The determination is made on the condition that a state having a predetermined temperature difference continues for a predetermined time (for example, 3 seconds) in consideration of blurring of detection by the thermistor. If there is no temperature difference necessary for this temperature difference determination, a history of temperature difference determination (reverse heat exchange determination) “NG” is stored (step S17), and the process proceeds to an end process (step S14). If there is a predetermined temperature difference (YES in step S9), the warm heat valve 82 is opened, the hot water on the heating circuit 22 side is circulated and supplied to the bath heater 81, and the preheating of the hot water is started by recovering the exhaust heat from the bath water. At the same time, a timer for the second set time (for example, 30 minutes) is started as the maximum duration of the exhaust heat utilization operation (step S10). The second set time may be set to an elapsed time during which the exhaust heat recovery can be performed effectively, although the temperature of the bath water gradually decreases due to the recovery of exhaust heat from the bath water by liquid-liquid heat exchange. The second set time is naturally shorter than the first set time.

  The detected temperature of the bathtub water thermistor 85 (tub water temperature; bath return temperature) is lower than the temperature value obtained by adding the minimum set temperature difference (for example, a temperature difference of 8 ° C.) to the detected temperature value of the low temperature thermistor 77. (YES in step S11), whether the second set time has elapsed even if the temperature is not low (NO in step S11, YES in step S12), or even if the second set time has not elapsed When the interruption of the heating operation or the interruption of the heating operation occurs (NO in step S12, YES in step S13), the process proceeds to the exhaust heat utilization operation end process in step S14. On the other hand, if all of these steps S11 to S13 are “NO”, wait until the temperature difference becomes smaller than the minimum set temperature difference or until the second set time elapses (YES in step S11). In step S12, YES), exhaust heat utilization operation end processing is performed. In short, if there is a necessary set temperature difference, exhaust heat utilization operation is started, and exhaust heat recovery from the bath water proceeds until the minimum set temperature difference is reached, or the residual heat of the bath water still remains even if exhaust heat recovery is continued. The exhaust heat utilization operation is continued until the second set time set as the maximum possible elapsed time elapses, and if the minimum set temperature difference cannot be secured or the second set time elapses, the exhaust heat utilization operation is performed. Is terminated.

  In the end process, the bath thermal valve 82 is closed to stop the circulation of hot water to the bath heater 81, the terminal thermal valve opened in step S2 is closed to stop the circulation with the heating terminal 75, and the reheating Both the circulation pump 84 and the heating circulation pump 62 are deactivated (step S14). Subsequent to the end of the exhaust heat utilization operation, the heating combustion burner 51 is combusted to start the heating operation. That is, the exhaust heat utilization operation is executed in the range of the second set time until the reserved heating operation is started.

  In short, if the conditions for permitting the operation of exhaust heat utilization are satisfied, the exhaust heat utilization operation starts on the condition that there is a residual heat amount that can be recovered from the bathtub water that is necessary for exhaust heat utilization. If the temperature of the bath water drops further, the exhaust heat utilization operation is terminated when the remaining heat amount of the bath water becomes such that exhaust heat cannot be recovered effectively. These conditions are determined and grasped based on the above temperature difference and set time.

  When the above exhaust heat utilization operation is executed, the residual heat of the bathtub water is recovered in the hot water on the heating circuit 22 side by the liquid-liquid heat exchange in the bath heater 81, reaching the heating reservation time and heating. When the operation is started, the hot water is in a preheated state. For this reason, compared with the case where there is no preheating due to the use of exhaust heat, the required heating amount to a predetermined high temperature water is reduced, and it is possible to save the gas consumption of the heating combustion burner 51 accompanying the execution of the heating operation. In addition, based on the circulation of hot water preheated by the heating terminal 75, it is possible to quickly start up to a predetermined heating state at the start of the heating operation.

Second Embodiment
FIG. 5 shows a flowchart of exhaust heat utilization operation control by the exhaust heat utilization control means 282a (see FIG. 2) in the heating system 1 according to the second embodiment of the present invention. In the second embodiment, as the exhaust heat utilization operation control, the control from the start to the end of the exhaust heat utilization operation is performed mainly based on the situation determination such as the passage of time without using the temperature difference determination. Only, this is different from the first embodiment. The structure of the other heating system 1 is the same as that of 1st Embodiment.

  That is, in the exhaust heat utilization operation control of the second embodiment, the same processes as steps S1 to S8 of the first embodiment are executed as steps S21 to S28, and the same processes as steps S15 and S16 are performed in steps S33 and S33. This is executed as S34. Then, the heating circulation pump (heating pump) 62 is turned on (step S27), and a predetermined forced circulation time (a time required for the bath water to circulate sufficiently) elapses from the circulation determination “OK” in step S26. (YES in step S28), the warm heat valve 82 is opened, the hot water on the heating circuit 22 side is circulated and supplied to the bath heater 81, and preheating of the hot water is started by exhaust heat recovery from the bath water, A timer for a second set time (for example, 30 minutes) is started as the maximum duration of the exhaust heat utilization operation (step S29).

  Then, whether the second set time (30 minutes) elapses (YES in step S30), or if a bathing operation interrupt or a heating operation interrupt occurs even if the second set time has not elapsed (in step S30) NO, YES in step S31), the process proceeds to the end process of exhaust heat utilization operation in step S32. On the other hand, if both of these steps S30 and S31 are “NO”, after the second set time has elapsed (YES in step S30), the exhaust heat utilization operation end process is performed. In short, if there is a necessary set temperature difference, exhaust heat utilization operation is started, and exhaust heat recovery from the bath water proceeds until the minimum set temperature difference is reached, or the residual heat of the bath water still remains even if exhaust heat recovery is continued. The exhaust heat utilization operation is continued until the second set time set as the maximum possible elapsed time elapses, and if the minimum set temperature difference cannot be secured or the second set time elapses, the exhaust heat utilization operation is performed. Is terminated.

  The termination process is the same as step S14 in the first embodiment (step S32). That is, the warm heat valve 82 is closed to stop the circulation of hot water to the bath heater 81, the terminal heat valve opened in step S2 is closed to stop the circulation with the heating terminal 75, and the recirculation circulation pump Both 84 and the heating circulation pump 62 are deactivated (step S32).

  In short, in short, it is within the time range from the end of bathing to the end of the first set time within the permission conditions (see FIG. 4) for performing the exhaust heat utilization operation in step S21 (tub water The amount of residual heat that can be recovered from the exhaust heat is required for exhaust heat utilization; see step SA4), and the third set time has elapsed since the end of combustion in the previous heating operation (exhaust heat) The exhaust heat utilization operation is started on the condition that the temperature of the hot water has decreased to a level at which it can be preheated by the recovery; see Step SA5), and the second set time has passed since the start of the exhaust heat utilization operation (tub water However, if the temperature drops further, the remaining heat amount of the bath water becomes such that the exhaust heat cannot be effectively recovered). Accordingly, it is unnecessary to operate the recirculation circulation pump 84 or the like without performing the temperature difference determination, that is, only for the execution of the temperature difference determination, and while suppressing the generation of the operation noise associated with the circulation pump operation, Waste heat recovery from water to warm water can be performed.

<Other embodiments>
The present invention is not limited to the first and second embodiments described above, but includes other various embodiments. That is, in the first and second embodiments, the third set time has elapsed since the end of the combustion in the previous heating operation as a permission condition for performing the exhaust heat utilization operation (step SA5 in FIG. 4). However, the present invention is not limited to this, and such a condition may be omitted.

  In addition, instead of the circulation determination process in each of the above embodiments, the water level in the bathtub B may be detected using the water level sensor 87 to detect and determine the presence of the residual water in the bathtub.

  Furthermore, in each said embodiment, although the temperature difference determination is performed using the bath water thermistor 85 and the low temperature thermistor 77, it replaces with this and uses the high temperature thermistor 76 instead of the low temperature thermistor 77, and this high temperature thermistor. You may make it perform the temperature difference determination of step S9-step S13 using 76 and the bath water thermistor 85. FIG.

It is a whole schematic diagram showing an example of a heating system to which an embodiment of the present invention is applied. It is a block diagram of the part which concerns on the waste heat utilization control means especially of the controller of FIG. It is a flowchart of waste heat utilization operation control of a 1st embodiment. It is a flowchart which shows the content of the waste heat utilization driving | operation implementation permission determination process of FIG. It is a flowchart of the waste heat utilization operation control of 2nd Embodiment.

Explanation of symbols

1 Heating system 2 Combined heat source machine (heat source machine)
22 Heating circuit (Heating side circulation circuit)
23 Recirculation circuit (Floor circuit)
77 Low temperature thermistor (hot water temperature detection sensor)
81 Bath heater (heat exchanger)
85 Bath water thermistor (bath water temperature sensor)
282 Waste heat utilization control means B Bathtub

Claims (6)

A heating terminal, a bathtub, and a heat source unit are provided. The heat source unit circulates and supplies hot water as a heating heat source to the heating terminal, and a bath side circulation that circulates bathtub water in the bathtub. A heating system comprising a circuit and a heat exchanger through which the bath water of the bath side circulation circuit and the hot water of the heating side circulation circuit are passed in a heat exchangeable manner,
Waste heat utilization control means for performing waste heat utilization operation for utilizing the waste heat of the residual water in the bathtub as a heat source for preheating warm water in the heating-side circulation circuit,
The exhaust heat utilization control means finishes the previous bathing operation including the heating operation for bathing in the bathtub when the heating operation execution reservation command for circulatingly supplying hot water to the heating terminal is input and set. Before the first set time elapses and before the start of the heating operation, the bath water in the bath-side circulation circuit and the hot water in the heating-side circulation circuit are respectively heated. A heating system configured to perform exhaust heat utilization operation through an exchanger. The heating system according to claim 1,
The said waste heat utilization control means is a heating system comprised so that a waste heat utilization operation may be performed in the time range of the 2nd setting time before execution start of heating operation. The heating system according to claim 1 or 2,
The exhaust heat utilization control means is configured to execute the exhaust heat utilization operation on the condition that a time equal to or longer than a third set time has elapsed since the end of the previous heating operation. . It is a heating system in any one of Claims 1-3,
The exhaust heat utilization control means is configured to stop the exhaust heat utilization operation when a start request for bathing operation including a bath water heating operation occurs during execution of the exhaust heat utilization operation. Heating system. It is a heating system in any one of Claims 1-3,
A bath water temperature detection sensor for detecting the temperature of the bath water in the bath side circulation circuit, and a hot water temperature detection sensor for detecting the temperature of the hot water in the heating side circulation circuit,
The exhaust heat utilization control means is configured to start the exhaust heat utilization operation on condition that the detected temperature of the bath water has a temperature difference greater than the required set temperature difference than the detected temperature of the hot water. , Heating system. A heating terminal, a bathtub, and a heat source unit are provided. The heat source unit circulates and supplies hot water as a heating heat source to the heating terminal, and a bath side circulation that circulates bathtub water in the bathtub. A heating system comprising a circuit and a heat exchanger through which the bath water of the bath side circulation circuit and the hot water of the heating side circulation circuit are passed in a heat exchangeable manner,
Bathtub water temperature detection sensor for detecting the temperature of the bath water in the bath side circulation circuit, the hot water temperature detection sensor for detecting the temperature of the hot water in the heating side circulation circuit, and the exhaust heat of the remaining water in the bathtub are circulated on the heating side A waste heat utilization control means for performing a waste heat utilization operation for use as a heat source for preheating the hot water of the circuit,
The exhaust heat utilization control means is configured such that when a heating operation execution reservation command for circulatingly supplying hot water to the heating terminal is input and set, the detection temperature of the bathtub water output from the bathtub water temperature detection sensor is the hot water temperature detection. On the condition that the temperature difference is more than the required set temperature difference than the detected temperature of the hot water output from the sensor, the bath water and the heating side circulation circuit of the bath side circulation circuit before the start of the heating operation described above The heating system is configured to perform exhaust heat utilization operation by passing each of the hot water through the heat exchanger.

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