JP4670894B2 - Hot water storage water heater - Google Patents

Description

  The present invention stores hot hot water heated mainly using a heat pump unit that is operated using inexpensive midnight power as a main heat source, and also supplies hot water to a faucet, shower, bath, etc. It is about.

As a conventional hot water storage type hot water supply apparatus, for example, one disclosed in Patent Document 1 is known. That is, in this hot water storage type hot water supply device, hot water supplied to the lower side of the hot water storage tank is taken out from the lower side of the hot water storage tank and heated by an engine driven heat pump device as a main heat source, and then heated as hot water. Store from the top of the hot water tank. When hot water is supplied, hot water is taken out from the hot water pipe connected to the upper end side of the hot water tank and supplied to the faucet side, but the amount of heat (temperature) of the hot water flowing out of the hot water tank is insufficient. Operates a reheating device as an auxiliary heat source (arranged in series with respect to the hot water storage tank) provided between the hot water storage tank and the faucet of the hot water piping so that the required amount of heat is obtained. Yes.
JP 2001-255038 A

  However, in the hot water storage type hot water supply apparatus, the reheating apparatus is arranged in series on the hot water pipe with respect to the hot water storage tank, so that the reheating apparatus is operated when the amount of hot water flowing out of the hot water storage tank is insufficient. Therefore, depending on the amount of remaining hot water in the hot water storage tank, it may be necessary to cover the necessary amount of heat with the reheating device alone, and it may be necessary to set the reheating device as a large one in advance. In order to avoid this, it is conceivable to increase the amount of hot water to be stored in the hot water storage tank in advance. In this case, however, the hot water storage tank is enlarged or the energy consumption of the engine driven heat pump device is increased. End up.

  The present invention has been made in view of the above problems, and provides a hot water storage type hot water supply apparatus that can supply hot water by auxiliary heating with a smaller auxiliary heat source without increasing the size of the hot water storage tank. is there.

  In order to achieve the above object, the present invention employs the following technical means.

In the invention according to claim 1, in the hot water storage type hot water supply apparatus, a hot water storage tank (110) for storing hot water for hot water supply therein,
A heat pump unit (120) for taking out hot water to be replenished from the lower side of the hot water storage tank (110), boiling it into hot hot water, and flowing the hot water into the inside from the upper side of the hot water storage tank (110);
A lead-out pipe (114) connected to a lead-out port (113) provided on the upper side of the hot water storage tank (110), and leading the hot water in the hot water storage tank (110) to a hot water supply section ;
An auxiliary heat source (130) connected to the hot water storage tank (110) for heating the hot water in the hot water storage tank (110);
An outlet pipe (132) that connects the auxiliary heat source (110) and the middle of the outlet pipe (114) , and causes hot water heated by the auxiliary heat source (130) to flow into the outlet pipe (132) ;
A mixing valve (133) which is provided at a connection portion between the outlet pipe (114) and the outlet pipe (132) and adjusts a mixing ratio of hot water flowing out from the outlet port (113) and hot water flowing out from the outlet pipe (132 ); ,
An auxiliary heat source circulation circuit (134) that is arranged in parallel with the heat pump unit (120), heats hot water flowing out of the hot water storage tank (110) with the auxiliary heat source (130), and flows into the hot water storage tank (110);
The heat pump unit (120) is operated to control boiling-up mainly at a predetermined time period determined according to the power cost, and the auxiliary heat source (130) and the mixing valve (133) are controlled according to the amount of hot water in the hot water storage tank (110). And a control device (150) for controlling the hot water supply to the hot water supply section.

Accordingly, the hot water supply control is performed on the hot water supply section by using both the heat quantity of the hot water in the hot water storage tank (110) obtained by the boiling control and the heat quantity of the hot water (or hot water supply water) obtained by the auxiliary heat source (130) in good balance. Therefore, the hot water storage tank (110) can be handled with a smaller auxiliary heat source (130) without increasing the size of the hot water storage tank (110).
In addition, the auxiliary heat source (130) can be heated up. If it is in a time zone other than the predetermined time zone, the auxiliary heat source (130) is used to increase the temperature of the heat pump unit (120). It can be heated up at a low cost.

Moreover, in invention of Claim 2 , hot water in a hot water storage tank (110) is the intermediate part in the up-down direction of this hot water storage tank (110) in the auxiliary heat source (130) in the invention of Claim 1. (113a), and the controller (150) controls the hot water from the outlet (113) by the mixing valve (133) when the heat quantity of the hot water in the intermediate part (113a) is equal to or greater than a predetermined heat quantity. The hot water passing through the auxiliary heat source (130) from the intermediate part (113a) is preferentially used for hot water supply control.

  Thus, after the boiling control, intermediate hot water that is formed between the hot water stored on the upper side of the hot water storage tank (110) and the low temperature hot water (hot water supply) stored on the lower side of the hot water storage tank (110) ( 113a) can be preferentially used, so that the amount of hot water in the hot water storage tank (110) can be used without waste while minimizing the heating in the auxiliary heat source (130).

According to a third aspect of the present invention, in the second aspect of the present invention, the controller (150) causes the hot water in the hot water storage tank (110) to fall below the predicted usage amount until the next boiling-up control is executed, and the hot water runs out. When the auxiliary heat source (130) and the mixing valve (133) are operated, at least the auxiliary hot water from the outlet (113) and the hot water from the auxiliary heat source (130) are operated. Hot water from the heat source (130) side is used for hot water supply control.

  As a result, boiling is increased by the auxiliary heat source (130), hot water supply control can be performed, and the heat pump unit (120) is not operated in a time zone other than the predetermined time zone, so that boiling can be inexpensively performed.

In the invention according to claim 4 , the control device (150) determines that there is a possibility that the hot water in the hot water storage tank (110) will fall below the predicted usage amount and run out of hot water until the next boiling control execution. At least one of the heat pump unit (120) and the auxiliary heat source (130) is operated to increase boiling into the hot water storage tank (110).

  As a result, when boiling is performed using both the heat pump unit (120) and the auxiliary heat source (130), boiling can be increased in a short time, and the heat pump unit (120) in a time zone other than the predetermined time zone can be obtained. The auxiliary heat source (130) can be downsized while suppressing the power consumption. In addition, in the case where boiling is performed using only the auxiliary heat source (130), the heat pump unit (120) is not operated in a time zone other than the predetermined time zone, so that an inexpensive response is possible.

In the invention according to claim 5 , in the invention according to claim 4 , the control device (150) allows the heat pump unit (150) to be used when the time zone for performing boiling is a time zone other than the predetermined time zone. 120) and the auxiliary heat source (130), only the auxiliary heat source (130) is operated.

  As a result, the heat pump unit (120) is not operated in a time zone other than the predetermined time zone, so that it can be heated at a low cost.

In the invention according to claim 6 , in the invention according to claim 4 , the control device (150) has a time zone for performing boiling increase in a time zone other than a predetermined time zone, and can lead to hot water shortage. When the property is higher than a predetermined value, both the heat pump unit (120) and the auxiliary heat source (130) are operated.

  This makes it possible to increase boiling in a short time and reliably prevent hot water from running out.

The invention according to claim 7 is characterized in that the control device (150) calculates the predicted use amount from the actual use of hot water in a predetermined period before the previous day.

  Thereby, since the precision of the required amount of boiling increase can be raised, the use energy of a heat pump unit (120) or an auxiliary heat source (130) can be reduced.

In the invention according to claim 8 , when the temperature of hot water supplied to the heat pump unit (120) exceeds a predetermined temperature when performing the boiling control, the control device (150) of the heat pump unit (120). The operation is stopped and the auxiliary heat source (130) is operated.

  Usually, the coefficient of performance of the heat pump unit (120) (the ratio of the heat radiation energy to the refrigerant compression energy) decreases due to the temperature difference from the heat pump unit (120) side becoming smaller as the temperature of the hot water is increased. Then, in such a state, the heat pump unit (120) is not used, and a decrease in the coefficient of performance can be prevented, so that an increase in power consumption of the heat pump unit (120) can be suppressed.

The invention according to claim 9 is characterized in that the heat pump unit (120) is used over a critical pressure when the internal refrigerant is compressed.

  As a result, the temperature of the refrigerant in the heat pump unit (120) can be increased, and the temperature difference from the hot water supply can be increased to efficiently boil hot water.

In the invention described in claim 9 , as in the invention described in claim 10 , carbon dioxide is preferably used as the refrigerant.

  In addition, the code | symbol in the parenthesis attached | subjected to each said means shows the correspondence with the specific means of embodiment description later mentioned.

(First embodiment)
A first embodiment of the present invention will be described below with reference to FIGS. 1 is a schematic diagram showing a schematic configuration of a hot water storage type hot water supply apparatus (hereinafter referred to as a hot water supply apparatus) 100 in the first embodiment, and FIG. 2 is a flowchart showing a control flow in hot water supply control.

  The hot water supply apparatus 100 has a hot water storage tank 110 that stores high-temperature hot water heated by the heat pump unit 120, and an auxiliary heat source 130 is added according to the amount of heat of the hot water in the hot water storage tank 110, such as a faucet, shower, bath, etc. It is assumed that hot water is supplied to the hot water supply section.

  The hot water storage tank 110 is a metal tank (for example, made of stainless steel) having excellent corrosion resistance, and a heat insulating material (not shown) is disposed on the outer peripheral portion so that hot water can be kept warm for a long time. The hot water storage tank 110 has a vertically long shape, and an introduction port 111 is provided on the bottom surface (lower end side), and an introduction pipe for introducing hot water (city water) into the lower side of the hot water storage tank 110 through the introduction port 111. 112 is connected.

  On the other hand, a lead-out port 113 is provided on the upper surface (upper end side) of the hot water storage tank 110, and a lead-out pipe 114 for leading out hot water in the hot water storage tank 110 is connected to the lead-out port 113. The outlet side of the outlet pipe 114 is connected to the hot water supply section. The outlet pipe 114 is provided with a flow rate counter 141 and a thermistor 142, the flow rate counter 141 provides information on the flow rate of the hot water flowing through the outlet pipe 114, and the thermistor 142 provides the hot water flow through the outlet pipe 114. The temperature information is output to the control device 150 described later.

  A pipe 115 branched from the introduction pipe 112 is connected to the outlet pipe 114, and a first mixing valve 116 is provided at the junction of the outlet pipe 114 and the pipe 115. The first mixing valve 116 can adjust the mixing ratio between the hot water from the outlet pipe 114 and the hot water from the pipe 115 by adjusting the opening area ratio. The first mixing valve 116 is an electric valve that adjusts the opening degree of the outlet pipe 114 and the pipe 115 by driving a valve body by a drive source such as a servo motor, and operates according to a control signal from the control device 150 described later. At the same time, the operating state is output to the control device 150.

  A discharge port 117 for discharging hot water in the hot water storage tank 110 is provided on the bottom surface of the hot water storage tank 110, and hot water is sucked into the upper surface of the hot water storage tank 110 above the hot water supply water in the hot water storage tank 110 ( A suction port 118 is provided. The discharge port 117 and the suction port 118 are connected by a heat pump circulation circuit 119, and a part of the heat pump circulation circuit 119 is disposed in the heat pump unit 120.

  The heat pump unit 120 is a main heat source that forms a well-known heat pump cycle. Here, carbon dioxide is used as a refrigerant, and the refrigerant is used after being compressed to a critical pressure or more. A portion of the heat pump circuit 119 disposed in the heat pump unit 120 is provided with a heat exchanger (not shown), and hot water in the hot water storage tank 110 discharged from the discharge port 117 by a pump (not shown) is compressed to a high temperature. The hot water is heated by exchanging heat with the refrigerant (for example, 90 ° C.) and returned to the hot water storage tank 110 through the suction port 118 to boil hot water in the hot water storage tank 110. The heat pump unit 120 is operated by a control signal from the control device 150 described later, and outputs an operation state to the control device 150.

  Furthermore, a plurality of thermistors 143 are arranged on the outer wall surface of the hot water storage tank 110 at predetermined intervals in the vertical direction so that temperature information at each water level in the hot water storage tank 110 is output to the control device 150 described later. ing.

  As a feature of the present invention, an auxiliary heat source 130 is provided so as to be parallel to the hot water storage tank 110. The auxiliary heat source 130 is, for example, a small gas water heater that can heat hot water flowing inside by a combustion flame. An inflow pipe 131 branched from the pipe 115 is connected to the hot water inflow side of the auxiliary heat source 130, and an outflow pipe 132 is provided on the outflow side of the hot water, and the leading end side of the outflow pipe 132 is the outlet pipe 114. Between the outlet 113 and the hot water supply unit and at a position upstream of the first mixing valve 116.

  Further, a second mixing valve (corresponding to the mixing valve of the present invention) 133 similar to the first mixing valve 116 is provided at a connection portion (junction point) between the outlet pipe 114 and the outlet pipe 132, and the outlet pipe 114 is provided. The mixing ratio of hot water from the hot water storage tank 110 flowing through the inside and the hot water or hot water from the auxiliary heat source 130 flowing through the outflow pipe 132 can be adjusted. The second mixing valve 133 is operated by a control signal from the control device 150 to be described later, and outputs the operating state to the control device 150.

  Based on the flow rate signal from the flow rate counter 141, the temperature signal from the thermistors 142 and 143, the hot water supply switch signal input by the user to the hot water supply remote controller 151, the hot water supply set temperature signal, and the like, the control device 150 performs the heat pump unit 120 and the auxiliary heat source 130. The operation of both mixing valves 116 and 133 is controlled. The hot water remote controller 151 is installed in the vicinity of a place where hot water is used, such as in a bathroom or kitchen, and the main body of the controller 150 is installed in the hot water storage tank 110.

  Next, the operation of hot water supply apparatus 100 based on the above configuration will be described.

1. Boil-up control First, when the hot water supply switch of the hot water remote controller 151 is turned on by the user, the control device 150 mainly uses a low-night time zone (a predetermined time zone determined according to the power cost in the present invention). The heat pump unit 120 is operated during, for example, the time zone from 23:00 on the day to 7 o'clock on the next day, and the hot water in the hot water storage tank 110 is heated and stored as a necessary amount of hot water.

  Specifically, the control device 150 calculates and stores the amount of hot water used every day (the amount of heat obtained by the product of the temperature and the flow rate of hot water) from the flow rate information from the flow rate counter 141 and the temperature information from the thermistor 142. . Here, the day break is the start time (23:00) of the midnight time zone.

  And the calorie | heat amount for hot water supply required on the day is calculated. Here, the average value + standard deviation of the actual hot water supply amount for each day in the past predetermined period (for example, seven days before the previous day) is defined as the required hot water supply heat amount for the day. Further, the amount of remaining hot water in the hot water storage tank 110 of the previous day is calculated from the temperature information at each water level from the thermistor 143, and the amount obtained by subtracting the remaining amount of hot water from the required amount of heat for hot water supply is defined as the amount of heating heat. Then, the heat pump unit 120 is operated at midnight, and hot water corresponding to the amount of heat generated is stored in the hot water storage tank 110. The thermistor 143 monitors whether the hot water temperature in the hot water storage tank 110 has reached the boiling temperature.

2. Hot Water Supply Control When the user uses hot water in the hot water supply section, the control device 150 performs hot water supply control based on the flowchart shown in FIG. First, in step S100, it is determined whether there is a possibility of hot water running out from 17:00 to 23:00 (possibility of hot water running out). Specifically, this hot water run-off determination is performed as follows. That is, the amount of remaining hot water in the hot water storage tank 110 at the time of 17:00 and the required amount of heat required from 17:00 to 23:00 (corresponding to the predicted usage in the present invention) are calculated, and the amount of remaining hot water is calculated. When the amount of heat falls below the required amount of heat, it is determined that there is a risk of running out of hot water. The amount of remaining hot water is calculated from the temperature information at each water level from the thermistor 143 in the same manner as in the above-described boiling control, and the required amount of heat is, for example, every day from 17:00 to 23:00 for 7 days before the previous day. The average value of the actual hot water supply amount (corresponding to the actual use of hot water in the present invention) + the standard deviation σ is calculated.

  If it is determined in step S100 that there is no risk of running out of hot water, the opening degree of the second mixing valve 133 is adjusted so that the opening degree on the outlet pipe 114 side (hot water storage tank 110 side) becomes 100% (step S110). Further, the opening degree of the first mixing valve 116 is adjusted in accordance with the hot water supply set temperature from the hot water remote controller 151 (step S120), and hot water from the hot water storage tank 110 and hot water from the pipe 115 are mixed. Hot water is discharged from the leading end of the outlet pipe 114 to the hot water supply section.

  However, if it is determined in step S100 that there is a risk of running out of hot water (assuming that the amount of hot water used by the user by 17:00 is large and the amount of remaining hot water in the hot water storage tank 110 is predicted to be insufficient), the second mixing valve 133 The opening is adjusted so that both the outlet pipe 114 side (hot water storage tank 110 side) and the outflow pipe 132 side (auxiliary heat source 130 side) are opened (step S130), the auxiliary heat source 130 is operated, and boiling is increased (step S140). ). That is, in addition to the hot water from the hot water storage tank 110, the hot water heated up by the auxiliary heat source 130 is also used at the same time. In addition, about the opening degree of the 2nd mixing valve 133, the opening degree by the side of the outflow pipe 132 is enlarged, so that the difference of the required calorie | heat amount at the time of hot water determination and residual hot water quantity is large. Then, the first mixing valve 116 is adjusted in the same manner as above (step S120), hot water from the pipe 115 is mixed, and the hot water is discharged from the tip of the outlet pipe 114 to the hot water supply section.

  As a result, hot water control can be performed on the hot water supply section by using both the heat quantity of the hot water in the hot water storage tank 110 (residual hot water heat quantity) obtained by the boiling control and the heat quantity of hot water obtained by the auxiliary heat source 130 in a well-balanced manner. It is possible to cope with a smaller auxiliary heat source 130 without increasing the size of the tank 110.

  In addition, when there is a risk of running out of hot water, hot water is generated (heated up) by the auxiliary heat source 130 and hot water supply control is executed, so that the heat pump unit 120 is not operated in a time zone other than the midnight time zone. Can be heated at a low cost.

  Furthermore, since the required amount of heat after 17:00 (predicted usage) is calculated from the amount of hot water supply in a predetermined period before the previous day (learning control), the required amount of boiling increase can be improved. In addition, the energy used by the auxiliary heat source 130 can be reduced.

  As in the present embodiment, the heat pump unit 120 uses carbon dioxide as the refrigerant, and heat exchange can be performed with higher efficiency than hot water using a supercritical region by using a supercritical region. It becomes possible to boil high-temperature hot water efficiently.

(Second Embodiment)
A second embodiment of the present invention is shown in FIGS. 2nd Embodiment changes the inflow path to the auxiliary heat source 130 with respect to the said 1st Embodiment. FIG. 3 is a schematic diagram showing a schematic configuration of the hot water supply apparatus 100 in the second embodiment, and FIG. 4 is a flowchart showing a control flow in hot water supply control.

  In the second embodiment, as shown in FIG. 3, the inflow pipe 131 that flows into the auxiliary heat source 130 is connected from an intermediate outlet 113 a that is an intermediate portion in the vertical direction of the hot water storage tank 110. Hot water in the hot water storage tank 110 is supplied to the heat source 130.

  Here, since the hot water in the hot water storage tank 110 is filled with hot water (90 ° C.) immediately after boiling, the hot water is supplied from the intermediate outlet 113a to the auxiliary heat source 130. As hot water is used, hot water is replenished from the lower inlet 111 of the hot water tank 110, so that the hot water in the hot water tank 110 is heated between the hot water on the upper side and the hot water on the lower side. In this case, medium temperature hot water is mainly supplied from the intermediate outlet 113a to the auxiliary heat source 130.

  In the hot water supply apparatus 100 formed in this way, the control device 150 performs the same control as the first embodiment for boiling, but the content of the hot water control is different, and the control is a flowchart of FIG. Will be described below.

  First, in step S200, the hot water temperature (corresponding to the heat quantity of the hot water of the present invention) at the intermediate outlet 113a in the hot water storage tank 110 corresponds to a predetermined temperature (corresponding to the predetermined heat quantity of the present invention, for example, 90 The temperature of the second mixing valve 133 is determined so that the opening on the outflow pipe 132 side is 100%. Is adjusted (step S205). Then, the auxiliary heat source 130 is stopped (step S210), and the opening degree of the first mixing valve 116 is adjusted to mix the hot hot water from the hot water storage tank 110 and the hot water supplied from the pipe 115 for derivation. Hot water is discharged from the tip of the pipe 114 to the hot water supply unit (step S215). That is, when the hot water temperature of the intermediate outlet 113a is higher than a predetermined temperature, the hot water in the hot water storage tank 110 is used after flowing out of the intermediate outlet 113a through the auxiliary heat source 130 (OFF state) and the second mixing valve 133. .

  However, if it is not determined in step S200, that is, if it is determined that the hot water temperature of the intermediate outlet 113a is lower than the predetermined temperature, it is then determined in step S220 whether there is a risk of hot water running out. If it is determined that there is no danger of running out of hot water, the heat pump unit 120 is stopped (step S225), and the opening degree of the second mixing valve 133 is adjusted so that both the outlet pipe 114 side and the outlet pipe 132 side are opened. (Step S230) With the auxiliary heat source 130 stopped (Step S235), hot water is supplied in Step S215. That is, even if the hot water temperature at the intermediate outlet 113a falls below a predetermined temperature, both hot hot water from the outlet 113 and medium hot water from the intermediate outlet 113a are used if there is no risk of running out of hot water. And mixed with hot water from the pipe 115.

  On the other hand, if it is determined in step S220 that there is a risk of running out of hot water, the opening of the second mixing valve 133 is adjusted so that the opening on the outflow pipe 132 side becomes 100% (step S240), and the auxiliary heat source 130 is activated. (Step S245). Then, hot water is supplied by adjusting the opening of the first mixing valve 116 (step S250). That is, when the hot water temperature at the intermediate outlet 113a falls below a predetermined temperature and there is a risk of running out of hot water, first, the intermediate hot water from the intermediate outlet 113a is heated by the auxiliary heat source 130 and then from the pipe 115. The hot water is mixed with hot water. In step S255, it is determined whether or not the hot water temperature at this time is higher than the set temperature from the hot water supply remote controller 151. If it is determined that the temperature is higher, the process returns to step S200.

  However, if it is determined in step S255 that the tapping temperature is lower than the set temperature, the opening of the second mixing valve 133 is further adjusted so that both the outlet pipe 114 side and the outlet pipe 132 side are opened (step S260). Hot water is supplied by adjusting the opening of the first mixing valve 116 (step S265). That is, when the hot water temperature at the intermediate outlet 113a is lower than the predetermined temperature and there is a risk of running out of hot water, and the hot water temperature is lower than the set temperature, the hot water from the outlet 113 and the intermediate outlet 113a The hot water obtained by heating the medium temperature hot water with the auxiliary heat source 130 is mixed with the hot water supplied from the pipe 115 and discharged. In step S270, it is determined whether or not the hot water temperature at this time is higher than the set temperature from the hot water remote controller 151. If it is determined that the temperature is high, the process returns to step S200. The hot water storage tank 110 is heated up, and the process returns to step S220.

  Accordingly, when the hot water in the hot water storage tank 110 is higher than the predetermined temperature, the hot water in the hot water storage tank 110 can be preferentially used without using the auxiliary heat source 130. Can be used without waste.

  When there is a risk of running out of hot water, hot water obtained by heating medium hot water with the auxiliary heat source 130 and hot water remaining in the hot water storage tank 110 are used to supply hot water. It is possible to control hot water supply by reheating using 130, and it is not necessary to operate the heat pump unit 120 in a time zone other than the midnight time zone, so that it is possible to reheat at a low cost.

(Third embodiment)
A third embodiment of the present invention is shown in FIGS. 3rd Embodiment adds the boiling increase function to the hot water storage tank 110 by the auxiliary heat source 130 with respect to the said 2nd Embodiment. FIG. 5 is a schematic diagram showing a schematic configuration of the hot water supply apparatus 100 in the third embodiment, and FIG. 6 is a flowchart showing a control flow in the boiling increase control.

  In the third embodiment, as shown in FIG. 5, an auxiliary heat source circulation circuit 134 is provided that passes through the auxiliary heat source 130 from the bottom surface of the hot water storage tank 110 and is connected to the upper surface of the hot water storage tank 110, and the auxiliary heat source 130 and the hot water storage tank A pump 135 and a valve 136 are provided in a flow path between the upper surface of 110. The pump 135 circulates hot water from the lower side of the hot water storage tank 110 to the upper side of the hot water storage tank 110 via the auxiliary heat source 130. The valve 136 opens and closes the auxiliary heat source circulation circuit 134.

  Further, valves 137 and 138 are provided on the inflow pipe 131 and the outflow pipe 132 in the auxiliary heat source 130, respectively, so that the inflow pipe 131 and the outflow pipe 132 are opened and closed.

  The pump 135 and the valves 136 to 138 are operated by a control signal from the control device 150 and output an operation state to the control device 150.

  In the hot water supply device 100 formed in this way, the control device 150 performs the boiling control and the hot water supply control in the same manner as in the second embodiment, but the content of the boiling increase control when there is a risk of running out of hot water. The control will be described below with reference to the flowchart of FIG.

  First, in step S300, it is determined whether or not there is a possibility of running out of hot water. If it is determined that there is no possibility of running out of hot water, there is no need to increase boiling, so that the heat pump unit 120, the auxiliary heat source 130, and the pump 135 are in a stopped state. (Step S310). However, if it is determined in step S300 that there is a risk of running out of hot water, it is further determined in step S320 whether the time zone at this time is a midnight time zone. If it is determined that it is the midnight time zone, the auxiliary heat source 130 and the pump 135 are stopped, and heating is performed by operating the heat pump unit 120 of the main heat source (step S330).

  On the other hand, if it is determined in step S320 that it is not in the midnight time zone (daytime / night time zone from 7 o'clock to 23 o'clock), the heat pump unit 120 is not used and the auxiliary heat source 130 and the pump 135 are operated to increase boiling. . At this time, the valve 136 is opened and the valves 137 and 138 are closed, so that hot water from the hot water storage tank 110 circulates through the auxiliary heat source circulation circuit 134 and is heated by the auxiliary heat source 130 (step S340). ). When performing hot water supply control, the valves 137 and 138 are opened, and the valve 136 is closed.

  As a result, it is also possible to increase boiling in the auxiliary heat source 130, and in the case of a time zone other than the midnight time zone, the heat pump unit 120 is not operated by performing boiling increase using the auxiliary heat source 130, Boiling can be done at low cost.

  In the third embodiment, as shown in the flowchart of FIG. 7, after determining whether or not it is the midnight time zone in step S320, step S335 is further provided, and is there a high possibility that the hot water will run out? It may be determined whether or not to respond to the increase in boiling.

  That is, as a determination as to whether or not there is a high possibility of running out of hot water, if the remaining hot water heat quantity at 17:00 is more than half of the required heat quantity from 17:00 to 23:00, the possibility of hot water running out is low. As a matter of course, the above-described step S340 is dealt with (both are heated by the operation of the auxiliary heat source 130 and the pump 135). However, if it is determined in step S335 that the amount of heat of the remaining hot water is ½ or less of the required heat amount and there is a high possibility that the hot water will run out, the heat pump unit 120 is operated in addition to the auxiliary heat source 130 and the pump 135 to increase boiling. This is performed (step S350).

  This makes it possible to increase boiling in a short time and reliably prevent hot water from running out.

(Fourth embodiment)
A fourth embodiment of the present invention is shown in FIG. In the fourth embodiment, the boiling control in the first to third embodiments is changed. The flowchart shown in FIG. 8 is a subroutine flow in the boiling control explained in the first embodiment.

  In other words, the control device 150 basically operates the heat pump unit 120 at midnight to heat the hot water in the hot water storage tank 110 and store it as a necessary amount of hot water, but during the boiling in step S400, the heat pump It is determined whether or not the temperature of the hot water supplied to the unit 120 is equal to or lower than a predetermined temperature (for example, 40 ° C.). If the temperature is determined to be equal to or lower than the predetermined temperature, the heat pump unit 120 is continuously operated to continue boiling. (Step S410). The temperature of the hot water supplied to the heat pump unit 120 is detected by the lowermost thermistor 143 among the thermistors 143 provided on the outer wall surface of the hot water storage tank 110.

  Then, it is determined whether or not the boiling has been completed. If not completed, the process returns to step S400, and if completed, the boiling is terminated.

  On the other hand, if NO in step S400, that is, if it is determined that the temperature of the hot water supply has exceeded the predetermined temperature, the heat pump unit 120 is stopped, the auxiliary heat source 130 and the pump 135 are operated, and boiling is continued (step S430). Proceed to S420.

  Normally, the coefficient of performance of the heat pump unit 120 (ratio of the heat radiation energy to the refrigerant compression energy) decreases due to the temperature difference from the heat pump unit 120 side becoming smaller as the temperature of the hot water is increased. Since the heat pump unit 120 is not used in a state and the coefficient of performance can be prevented from being lowered, an increase in power consumption of the heat pump unit 120 can be suppressed.

(Other embodiments)
In the first to third embodiments, the auxiliary heat source 130 has been described as a water heater using gas as fuel, but is not limited thereto, and may be a water heater using kerosene or the like as fuel. In addition, carbon dioxide is used as the refrigerant of the heat pump unit 120 and the pressure is compressed to a critical pressure or higher. However, the refrigerant is not limited to this, and a CFC refrigerant (R410 or the like) is used or the compression pressure is operated below the critical pressure. Also good.

It is a schematic diagram which shows schematic structure of the hot water storage type hot water supply apparatus in 1st Embodiment of this invention. It is a flowchart which shows the control flow of the hot water supply control in 1st Embodiment. It is a schematic diagram which shows schematic structure of the hot water storage type hot water supply apparatus in 2nd Embodiment of this invention. It is a flowchart which shows the control flow of the hot water supply control in 2nd Embodiment. It is a schematic diagram which shows schematic structure of the hot water storage type hot water supply apparatus in 3rd Embodiment of this invention. It is a flowchart which shows the control flow of the boiling increase control in 3rd Embodiment. It is a flowchart which shows the control flow of the boiling increase control in the modification of 3rd Embodiment. It is a flowchart which shows the control flow of the boiling control in 4th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Hot water storage type hot water supply apparatus 110 Hot water storage tank 113 Outlet 113a Intermediate outlet (intermediate part)
114 Outlet pipe 120 Heat pump unit 130 Auxiliary heat source 132 Outflow pipe 133 Second mixing valve (mixing valve)
134 Auxiliary heat source circulation circuit (circulation circuit)
150 Controller

Claims (10)

A hot water storage tank (110) for storing hot water for hot water supply,
A heat pump unit (120) for taking out hot water to be replenished from the lower side of the hot water storage tank (110), boiling the hot water into hot water, and flowing the hot water into the inside from the upper side of the hot water storage tank (110); ,
A lead-out pipe (114) connected to a lead-out port (113) provided on the upper side of the hot water storage tank (110), and leading the hot water in the hot water storage tank (110) to a hot water supply section ;
An auxiliary heat source (130) connected to the hot water storage tank (110) for heating hot water in the hot water storage tank (110);
An outflow pipe (132) for connecting the auxiliary heat source (110) and the middle of the outlet pipe (114), and flowing hot water heated by the auxiliary heat source (130) into the outlet pipe (114) ;
A mixing valve that is provided at a connection portion between the outlet pipe (114) and the outlet pipe (132) and adjusts a mixing ratio of hot water flowing out from the outlet port (113) and hot water flowing out from the outlet pipe (132). (133),
An auxiliary heat source circulation circuit (134) that is arranged in parallel with the heat pump unit (120), heats hot water flowing out of the hot water storage tank (110) with the auxiliary heat source (130), and flows into the hot water storage tank (110). When,
The heat pump unit (120) is operated in a predetermined time period determined mainly depending on the power cost to control boiling, and the auxiliary heat source (130) and the heat source according to the amount of hot water in the hot water storage tank (110). A hot water storage type hot water supply apparatus comprising a control device (150) for operating the mixing valve (133) to control hot water supply to the hot water supply section. Wherein the auxiliary heat source (130), the hot water of the hot water storage tank (110) is supplied from the intermediate portion (113a) in the vertical direction of the hot water storage tank (110),
When the heat quantity of the hot water in the intermediate part (113a) is equal to or greater than a predetermined heat quantity, the control device (150) causes the mixing valve (133) to make the intermediate part with respect to the hot water from the outlet (113). The hot water storage type hot water supply apparatus according to claim 1, wherein hot water passing through the auxiliary heat source (130) from (113a) is preferentially used for the hot water supply control. When it is determined that there is a possibility that the hot water in the hot water storage tank (110) will fall below the predicted usage amount and the hot water runs out before the next boiling-up control is performed, the control device (150) 130) and the mixing valve (133) are operated so that at least hot water from the auxiliary heat source (130) side among hot water from the outlet (113) and hot water from the auxiliary heat source (130) is The hot water storage type hot water supply device according to claim 2 , wherein the hot water storage type hot water supply device is used for hot water supply control. When it is determined that there is a possibility that the hot water in the hot water storage tank (110) will fall below the predicted usage amount and the hot water runs out before the next boiling-up control is performed, the control device (150) The hot water storage system according to any one of claims 1 to 3 , wherein at least one of 120) and the auxiliary heat source (130) is operated to increase boiling into the hot water storage tank (110). Hot water supply device. The control device (150) includes the auxiliary pump (120) of the heat pump unit (120) and the auxiliary heat source (130) when the time zone when the boiling is performed is a time zone other than the predetermined time zone. The hot water storage type hot water supply apparatus according to claim 4 , wherein only the heat source (130) is operated. The control device (150) is configured so that the heat pump unit (120) is in a case where the time zone when the boiling is performed is a time zone other than the predetermined time zone, and the possibility that the hot water runs out is higher than a predetermined value. ) and hot water storage type water heater according to claim 4, wherein the actuating both of the auxiliary heat source (130). The hot water storage type hot water supply apparatus according to any one of claims 3 to 6 , wherein the control device (150) calculates the predicted usage amount from the actual use of hot water in a predetermined period before the previous day. The controller (150) stops the operation of the heat pump unit (120) if the temperature of the hot water supplied to the heat pump unit (120) exceeds a predetermined temperature when performing the boiling control. The hot water storage type hot water supply apparatus according to any one of claims 4 to 7 , wherein the auxiliary heat source (130) is operated. The hot water storage type hot water supply apparatus according to any one of claims 1 to 8 , wherein the heat pump unit (120) is used exceeding a critical pressure when an internal refrigerant is compressed. The hot water storage type hot water supply apparatus according to claim 9 , wherein the refrigerant is carbon dioxide.

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