JP5126432B1 - Water heater - Google Patents

Abstract

An object of the present invention is to provide a hot water supply apparatus that improves system efficiency and energy saving by preventing an increase in the temperature of hot water at the bottom of a hot water tank when performing a heat recovery operation.
A first hot water discharge pipe 3 connected to an upper portion of a hot water storage tank 1, a position where the first hot water discharge pipe 3 is connected in a vertical direction of the hot water storage tank 1, and a position where a water supply pipe 5 is connected. A second hot water outlet pipe 4 connected in between, a hot water outlet pipe 21 connected to the hot water tank 1, and a heat exchanger 20 connected to the hot water pipe 21 for recovering heat stored outside the hot water tank 1. And a heat recovery return pipe 22 that is connected to the heat exchanger 20 and the hot water tank 1 and conveys the recovered heat from the heat exchanger 20 to the hot water tank 1, and the heat recovery return pipe 22 is located above and below the hot water tank 1. A hot water supply apparatus characterized by being connected to the hot water storage tank 1 at a position higher than the connection position of the hot water storage tank 1 of the second hot water discharge pipe 4 in the direction.
[Selection] Figure 1

Description

  The present invention relates to a hot water supply apparatus for heating water in a hot water tank.

  Conventionally, this kind of hot water supply apparatus has a thing like FIG. 11, for example (for example, refer patent document 1).

  FIG. 11 shows a conventional hot water supply apparatus described in Patent Document 1. As shown in FIG.

  As shown in FIG. 11, a hot water tank 1, a heating means 2 for heating the hot water in the hot water tank 1, a first outlet pipe 3 connected to the upper part of the hot water tank 1, and an intermediate portion of the hot water tank 1 Second hot water pipe 4 connected, first mixing valve 6 for mixing hot water from first hot water pipe 3 of hot water tank 1 and hot water from second hot water pipe 4, and second hot water pipe 4 is provided with a hot water temperature detecting means 12 for detecting the hot water temperature in the hot water storage tank 1 at a position to which 4 is connected, and a hot water temperature setting means 30 for setting the hot water temperature, and the hot water temperature detected by the hot water temperature detecting means 12 is The first mixing valve is configured to discharge hot water from the second hot water discharge pipe 4 if it is equal to or higher than the hot water supply temperature set by the hot water supply temperature setting means 30, and to discharge hot water from the first hot water discharge pipe 3 if it is lower than the hot water supply set temperature. 6 channels are switched.

  Moreover, the bathtub 23, the heat exchanger 20 that exchanges the heat of the hot water tank 1 and the heat in the bathtub 23, the bath outlet pipe 21 connected to the upper part of the hot water tank 1, the heat exchanger 20 and the hot water tank 1 In order to convey hot water from the hot water tank 1 to the heat exchanger 20, the bath return pipe 22 connected to the lower part, the return position temperature detection means 26 installed in the vicinity of the connection position between the bath return pipe 22 and the hot water tank 1. Bath heat recovery pump 25, bathtub temperature detection means 24 for detecting the bathtub temperature in bathtub 23, and bathtub temperature setting means 31 for setting the use temperature in bathtub 23, which are detected by return position temperature detection means 26. When the detected temperature is the same as the boiling temperature, the boiling at night is finished and the heat recovery operation in the bathtub 23 is started. As a result, the heat of the bathtub 23 can be recovered in the lower part of the hot water tank 1, and the hot water of about 30 ° C. raised by the heat recovery is used by discharging from the second hot water discharge pipe 4 when using hot water the next day. can do.

JP 2009-198115 A

  However, the temperature of hot water in a general bathtub drops by about 6 ° C. in 6 hours, and the time when boiling at night ends is 7:00 when the midnight power time period ends. Therefore, about 20% of the heat in the bath 23 is lost due to heat dissipation during that time, and the heat recovery of the bath cannot be sufficiently performed.

  Further, in the configuration in which the bath return pipe 22 is connected below the second hot water discharge pipe 4 as in the prior art, when the hot water is filled in the morning, it is present when the recovery is performed after the hot water is filled. The entire low-temperature water will rise uniformly, and even if you use the second tapping pipe connected to the middle part of the hot water tank, the recovered heat will not be used up. Water that has entered the heating device increases the temperature of the heating device, which can lead to a deterioration in system efficiency.

  The present invention solves the above-mentioned conventional problems, and prevents a rise in the temperature of hot water at the bottom of a hot water tank when performing a heat recovery operation, thereby improving a system efficiency and improving energy saving. The purpose is to provide.

In order to solve the conventional problem, a hot water supply apparatus of the present invention includes a hot water storage tank, a first hot water pipe connected to the upper part of the hot water tank, a water supply pipe connected to the lower part of the hot water tank, A second hot water discharge pipe connected between the position where the first hot water discharge pipe is connected and the position where the water supply pipe is connected in the vertical direction of the hot water storage tank; and a bath connection connected to the hot water storage tank. A pipe, a heat exchanger connected to the bath outlet pipe for recovering the heat of the hot water in the bathtub, and connected to the heat exchanger and the hot water storage tank to convey the recovered heat from the heat exchanger to the hot water storage tank And a heat pump device that heats the hot water in the hot water storage tank, and the hot water taken out from the lower part of the hot water tank is heated by the heat pump device and then returned to the upper part of the hot water tank. in the heat recovery return piping of the hot water tank In the downward direction, said first tapping pipe to the hot water storage tank is connected to the hot water tank at a position between the position of the second hot water pipe is connected to the hot water tank and connected position It is characterized by.

  Thereby, when performing heat recovery operation, by preventing the temperature of the hot water at the bottom of the hot water tank from rising, it is possible to provide a hot water supply device that improves system efficiency and improves energy saving.

  ADVANTAGE OF THE INVENTION According to this invention, when performing heat recovery operation, the hot water supply apparatus which improved system efficiency and improved energy-saving property can be provided by preventing the raise of the temperature of the hot water of the hot water storage tank bottom part.

Configuration diagram of hot water supply apparatus in Embodiment 1 of the present invention Block diagram of heat recovery operation control means of the hot water supply device The figure which showed the change of the temperature distribution in the hot water tank by the heat recovery operation of the hot water supply device The figure which showed the efficiency of the heat pump apparatus as a 1st heating means of the hot-water supply apparatus The figure which showed the relationship between the heat recovery amount of the hot water supply device and the input of the heat pump device Flow chart of heat recovery operation control operation of the hot water supply device The block diagram of the hot-water supply apparatus in Embodiment 2 of this invention The block diagram of the hot-water supply apparatus in Embodiment 3 of this invention Circuit configuration diagram showing the flow direction of water and hot water during the heat recovery operation Circuit configuration diagram showing the flow direction of water and hot water during the same boiling operation Configuration diagram of conventional hot water supply equipment

1st invention WHEREIN: The hot water storage tank, the 1st hot water pipe connected to the upper part of the said hot water storage tank, the water supply pipe connected to the lower part of the said hot water storage tank, and the said 1st in the up-down direction of the said hot water storage tank a second hot water pipe, wherein a position tapping pipe is connected a water supply pipe is connected between the connection position, the bath往配pipe connected to the hot water tank, bathtub is connected to the bath往配tube A heat exchanger that recovers the heat of the hot water, a heat recovery return pipe that is connected to the heat exchanger and the hot water storage tank and conveys the recovered heat from the heat exchanger to the hot water storage tank, and in the hot water storage tank A hot water supply device that heats the hot water taken out from the lower part of the hot water storage tank and heats the hot water from the lower part of the hot water storage tank, and then returns the hot water to the upper part of the hot water storage tank. in the vertical direction of the vessel, the said hot water tank first It is the hot water supply device according to claim the hot water pipe is connected to the hot water tank at a position between the position of the second hot water pipe is connected to the hot water tank and connected position.

  As a result, the medium hot water generated by the heat recovery (hereinafter referred to as intermediate temperature water) flows into the upper part of the hot water tank, and the intermediate hot water generated by the hot water returning from the heat exchanger to the hot water tank is used as the second hot water. By effectively using the pipe, the amount of stored hot water can be used to the maximum extent possible, and the efficiency of the entire system is reduced by reducing the amount of medium-temperature water that causes a decrease in the heating efficiency of the heat pump. Therefore, there is an effect that good usability and high energy saving can be realized.

Moreover, since the hot water taken out from the lower part of the hot water tank is heated by the heat pump device and then returned to the upper part of the hot water tank, there is an effect that a hot water supply device with higher energy saving effect can be realized.

A second invention is the post-heat recovery operation is stopped by the front Stories heat exchanger, so that the input during the heating operation by the heat pump apparatus is substantially minimized, characterized in that stopping the heat recovery operation by the heat exchanger It is what.

Thus, based on the temperature distribution of the hot water storage tank during the heat recovery operation, the time point at which the heat consumption (power consumption) for boiling up the predetermined hot water storage amount by the heating means is judged to be minimum, and the heat recovery operation is stopped. Therefore, it is possible to improve the efficiency of the entire system, which is the original purpose, and to improve energy saving .

A third invention, as hot water heated by the pre-Symbol heat pump apparatus returns to the hot water storage tank, provided with a boiling return pipe from the switching means connected to said hot water storage tank, and control means, said bath The forward pipe is connected to the heat exchanger via the heat pump device and the switching means in order so that hot water in the lower part of the hot water tank flows to the heat exchanger, and the bathtub is moved by the heat exchanger. When performing the heat recovery operation for recovering the heat of the hot water in the hot water of the hot water storage tank, from the hot water storage tank in order of the bath outlet pipe, the heat pump device, the switching means, the heat exchanger, and the heat recovery return pipe. When the boiling operation is performed to heat the hot water in the hot water storage tank by the heat pump device, the bath outlet pipe, the heat pump device, the switching means, the boiling As flows hot water from the hot water tank in the order of raising the return pipe, is characterized in that said control means has a configuration for switching the switching means.

  Thereby, it can be set as the structure which uses a part of piping used at the time of heat recovery also at the time of the boiling operation of the hot water in a hot water tank, and can provide the hot water supply apparatus which implement | achieved cost reduction.

The fourth invention is characterized in that the heat exchanger is a plate type heat exchanger, and has a high heat exchange efficiency and is compact, so that the heat loss from the heat exchanger itself is small. By using this heat exchanger, there is an effect of improving the efficiency of heat recovery.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a diagram showing a configuration of a hot water supply apparatus according to the first embodiment of the present invention.

  In FIG. 1, a hot water supply apparatus includes a hot water tank 1, a heat pump device that is a heating means 2 for heating water in the hot water tank 1, a first hot water pipe 3 connected to the upper part of the hot water tank 1, and a hot water tank. 1 is connected between the water supply pipe 5 connected to the lower part of 1 and the position where the first hot water discharge pipe 3 and the water supply pipe 5 are connected, that is, in the height direction to the substantially central part of the trunk of the hot water tank 1. A first hot water pipe 4, a feed water branch pipe 10 branched from the feed water pipe 5, a first mixing valve 6 in which the first hot water pipe 3 and the second hot water pipe 4 are connected to the inlet side; A second mixing valve 7 connected to the outlet side of the first mixing valve 6 and a feed water junction pipe 8 and a feed water branch pipe 10 connected to the inlet side, and an outlet side of the second mixing valve 7 And a mixed water pipe 9 connected to.

  Furthermore, a hot water supply port 11 connected to the mixed water pipe 9, a medium temperature detection means 12 for detecting the hot water temperature flowing through the second hot water discharge pipe 4, and a combined temperature detection means for detecting the hot water temperature flowing through the hot water discharge pipe merging pipe 8. 13, a hot water supply temperature detection means 14 for detecting the temperature of hot water flowing through the mixed water pipe 9, a bath outlet pipe 21 connected to the lower part of the hot water tank 1, a heat exchanger 20 connected to the bath outlet pipe 21, and hot water storage A bath return pipe 22 connected to the upper part of the hot water tank 1 between the position where the first hot water pipe 3 is connected to the tank 1 and the position where the second hot water pipe 4 is connected to the hot water tank 1; A bathtub 23 connected to the heat exchanger 20, a bath heat recovery pump 25 that adjusts the amount of hot water flowing through the bath return pipe 22, and a bathtub temperature detection means 24 that detects the temperature of hot water flowing through the bathtub 23 are provided.

  In addition, based on the settings of the hot water supply temperature setting means 30 for setting the hot water supply temperature of the hot water supply port 11, the intermediate temperature detection means 12, the combined temperature detection means 13, the hot water supply temperature detection means 14, and the hot water supply temperature setting means 30. Hot water supply control means 31 for controlling the mixing valve 6 and the second mixing valve 7, the bath heat recovery pump 25, the bath circulation pump 26, and a plurality of hot water storage temperature detection means 1 a to detect the water temperature in the hot water tank 1. 1e and a heat recovery operation control means 32 for controlling the bath heat recovery pump 25 and the bath circulation pump 26 based on the outputs of the plurality of hot water storage temperature detection means 1a to 1e.

  FIG. 2 shows a block diagram of the heat recovery operation control means 32. The heat recovery operation control unit 32 includes a load prediction unit 101 that predicts a load from the start of heat recovery to the end of use of hot water, and a boiling operation control unit (not shown) that controls the boiling operation by the heat pump device 2. The required hot water storage amount acquisition unit 103 for acquiring the amount of hot water storage required for hot water use after hot water storage, the load amount obtained by the hot water storage temperature detection means 1a to 1e and the load prediction unit 101, and the use of hot water is completed. And a hot water storage temperature distribution measuring unit 103 for measuring the hot water storage temperature distribution.

The heat recovery operation control means 32 includes a required boiling heat quantity calculation unit 104 that calculates a required boiling heat quantity based on the results obtained by the required hot water storage heat quantity acquisition unit 103 and the hot water temperature distribution measurement unit 103, and hot water storage. Boiling completion hot water storage temperature distribution estimation unit 105 for estimating the current temperature distribution by the temperature distribution measurement unit 103 and the temperature distribution at the time of boiling completion from the required boiling heat amount calculation unit 104, and further the temperature by the hot water storage temperature distribution measurement unit 103 The boiling required input estimating unit 106 that estimates the input to the heat pump device 2 from the distribution to the estimated temperature distribution at the completion of boiling in the hot water storage temperature distribution estimating unit 105 at the completion of boiling, and this boiling required input estimation And a pump control unit 107 that controls the bath heat recovery pump 25 and the bath circulation pump 26 based on the time change of the estimated input value by the unit 106.

  About the hot water supply apparatus comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  As a basic operation in the use of hot water in a general home, hot water for the day is stored in the hot water tank 1 in the morning, and is sequentially used for hot water supply during an active time.

  When the amount of stored hot water is insufficient during the use of hot water, the heat pump device 2 may be operated as necessary, and an additional hot water storage operation may be performed. At the end of one day of hot water use, most of the hot water in the hot water tank 1 is replaced with hot water, and the hot water storage operation for the next use is performed again at midnight thereafter.

  At this time, the hot water supplied to the bathtub 23 for bathing is often left at a relatively high temperature with respect to the water temperature in the hot water tank 1 when the use of the hot water supply is ended. Heat recovery is performed in the hot water tank 1 before or during operation.

  Here, the operation | movement of the heat recovery of the hot water left in this bathtub 23 is demonstrated using FIGS.

  In the heat recovery operation, the water in the lower part of the hot water tank 1 and the hot water in the bathtub 23 are sent to the heat exchanger 20 by the operation of the bath heat recovery pump 25 and the bath circulation pump 26. It heats with 23 water and returns to the hot water tank 1 upper part.

  Due to the heat recovery operation, the temperature distribution in the hot water tank 1 changes in the order of 200, 201, 202 shown in FIG. That is, since the hot water in the bathtub 23 is lower than the temperature of the upper part of the hot water tank 1, the water that has been mixed and becomes medium-temperature water moves downward of the hot water tank 1.

  In particular, when the second hot water discharge pipe 4 is located below the heat recovery return port that is the connection port to the hot water storage tank 1 of the bath return pipe 22, it is possible to effectively use the medium hot water that has been lowered.

  Reference numeral 203 shown in FIG. 3 indicates a temperature distribution when hot water is generated after heat recovery. By having the 2nd tap pipe 4 in the lower part of a heat recovery return port, medium temperature water can be used ahead of high hot water, and the recovered heat can be used without waste.

  Next, as shown in FIG. 4, the operating efficiency of the heat pump device 2 decreases as the water temperature before heating increases.

  As can be seen from the temperature distribution of the hot water tank 1 shown in FIG. 3, the amount of heat by the heat pump device 2 after the heat recovery operation decreases as the amount of heat recovered from the bathtub 23 increases, but at the same time, the heat pump device 2 heats. Since the previous water temperature is high and the operation efficiency at the time of reheating is reduced, it is not necessarily energy saving to perform as much heat recovery as possible.

  That is, the input (heat consumption or power consumption) to the heat pump device 2 is obtained by subtracting the recovered heat obtained by the heat recovery operation from the necessary heating amount before heat recovery for obtaining the required hot water storage amount. As shown in FIG. 5, this value may have a minimum value with respect to the recovered heat amount.

  Therefore, in order to obtain a higher energy saving effect, it is necessary to stop the heat recovery operation from the bathtub 23 at the time when the input to the heat pump device 2 is substantially minimized in the reheating operation performed after the heat recovery operation is stopped. It is.

  As a specific method for finding the time point at which the value is approximately the minimum value, the change of the input value to the heat pump device 2 that is expected based on the temperature distribution of the hot water tank 1 measured at predetermined time intervals is obtained. Thus, the degree of decrease in the value is small or no longer decreases, or it is judged by starting to increase.

  As described above, as shown in FIG. 4, when the hot water in the hot water tank 1 is heated by the heat pump device 2, the temperature of the portion that transports water from the hot water tank 1 to the heat pump device 2 (this embodiment) In this case, the operating efficiency of the heat pump device 2 increases as the temperature of the lower part of the hot water tank 1 decreases. However, during the heat recovery operation from the bathtub 23, the hot water recovered from the bathtub 23 is stored in the hot water tank 1. There is a state in which the temperature of the portion where water is transferred from the hot water storage tank 1 to the heat pump device 2 starts to rise by charging the hot water.

  Therefore, at the time of the heat recovery operation from the bathtub 23, the temperature of the part that transports water to the heat pump device 2 of the hot water tank 1 is measured, and the heat recovery operation operation from the bathtub 23 is performed in the vicinity where the increase in the temperature starts to increase. By stopping this, it is possible to achieve substantially the maximum operating efficiency of the heat pump device 2 during the heating operation after the heat recovery operation.

  FIG. 6 is a flowchart of the operation of the heat recovery operation control means 32. First, the operation during the heat recovery operation is performed based on the load prediction until the end of the load obtained by the load prediction unit 101 and the temperature distribution of the hot water tank measured by the hot water storage temperature detecting means 1a to 1e. The temperature distribution of the hot water tank 1 at the time when the use of the hot water determined in 102 is completed is predicted (step 0).

  Next, from the required hot water storage amount acquired by the required hot water storage amount acquisition unit 103, the temperature distribution prediction at the time when the use of hot water obtained in step 0 is completed, and the operating conditions such as the boiling temperature of the heat pump device 2 The temperature distribution in the hot water storage tank 1 at the time of completion of the hot water storage operation is predicted, compared with the current temperature distribution, and the remaining heating amount Qr when heating with the heat pump device 2 from that time is obtained (step 1).

  Next, the average water temperature before boiling in the heat pump device 2 is estimated from the measured current temperature distribution until reaching the predicted temperature distribution at the time of completion of the hot water storage operation (step 2).

  Further, the average efficiency during hot water storage operation is obtained from the average water temperature obtained in step 2 and the characteristics of the heat pump device 2 shown in FIG. 4, and the remaining heating amount Qr obtained in step 1 is divided by this average efficiency to obtain hot water storage water. The input Qin during operation is estimated (step 3).

  Qin obtains a difference from Qin−f, which is a value obtained at the previous evaluation time, and if it is smaller than a predetermined deviation q, that is, if a change in the estimated input gradually becomes smaller and it is determined to be the minimum value, step In step 5, the hot water tank water transfer pump 5a and the bathtub water transfer pump 5b are stopped to end the heat recovery operation. When the difference between Qin and Qin−f is greater than or equal to q, the heat recovery operation is continued, and when the next evaluation time is reached (step 7), the above operation is repeated.

  In addition, as a supplement, at the first operation after the start of the heat recovery operation, step 6 is executed without performing the comparison at step 4.

  Here, the determination of the minimum value is performed because the degree of decrease is small, but when the input difference q between the evaluation times is 0, or when the sign of q is opposite to the previous evaluation time, That is, the heat recovery operation may be stopped with a minimum value when the estimated input starts to increase.

  In addition, the estimated input often increases or decreases while reaching the minimum value due to a measurement error of the temperature value of the hot water tank 1 to be measured.

  Therefore, by storing the estimated input at the latest several evaluation times, and determining whether the minimum value has been reached by using the moving average value, the determination accuracy of whether the minimum value has been reached is further improved. Can be increased.

  As described above, according to the first embodiment of the present invention, the heat recovered from the bathtub 23 is preferentially used by disposing the second outlet pipe 4 below the bath return pipe 22. In addition, by stopping the heat recovery operation when the input to the heat pump device 2 for boiling the required hot water for recovery is minimized, the efficiency improvement of the entire system, which is the original purpose, is realized. , Energy saving can be improved.

  As a configuration, the water in the lower part of the hot water tank 1 is taken out and heated by the heat exchanger 20 and returned to the upper part of the hot water tank 1, but the temperature distribution in the hot water tank 1 by the heat recovery operation is at the take-out position and the return position. It depends on the difference.

  Furthermore, the heat recovery speed and the like can be controlled by the capacity control of the bath heat recovery pump 25, and the operation efficiency changes depending on the difference in configuration and control.

  Therefore, in this embodiment, an appropriate take-out position and return position are set in consideration of usage, the capacity of the hot water storage tank 1 and the subsequent use of hot water, and the capacity control of the bath heat recovery pump 25 is controlled. Since the degree of freedom of optimization design that can be performed is high, it can be easily applied to a plurality of different models, and as a result, a large energy saving effect can be obtained by providing it to many users.

(Embodiment 2)
FIG. 7 is a diagram showing a configuration of a hot water supply apparatus according to the second embodiment of the present invention.

  The pouring hot water joining pipe 40 branched from the hot water joining pipe 8 in the first embodiment and the hot water feeding branch pipe 41 branched from the feed water pipe 5 are connected to the inlet of the third mixing valve 42, A pouring mixed water pipe 43 is connected to the outlet side of the third mixing valve 42 and poured into the bathtub 23 through a pouring pipe 44 branched from the bath mixing water pipe 43.

  The bath outlet pipe 21 in the first embodiment is configured to be shared with the water supply pipe 5, the pouring water branch pipe 41, and the pouring mixed water pipe 43.

  The control by the hot water supply control means 31 and the heat recovery operation control means 32 is the same as the control in the first embodiment, and the hot water tank 1 from the water supply pipe 5, the pouring water branch pipe 41, and the pouring mixed water pipe 43. Even if the water at the bottom is caused to flow out to the heat exchanger 20, the effect of preferentially using the intermediate temperature water from the second hot water discharge pipe 4 and the effect of preventing the efficiency from being lowered due to the influence of the intermediate temperature water are the same.

  In addition, since it is not necessary to newly provide a connection port at the upper part of the hot water tank 1, there is an effect of maintaining strength.

  Thus, according to the 2nd Embodiment of this invention, the efficiency fall by the bath return piping 22 can be prevented, without reducing the intensity | strength of the hot water storage tank 1. FIG.

(Embodiment 3)
FIG. 8 is a diagram showing the configuration of the hot water supply apparatus according to the third embodiment of the present invention.

In FIG. 8, the difference from the first embodiment is that a switching means 52 is provided, and a reheating branch branched from the first outlet pipe 3 through the switching means 52 to the primary inlet of the heat exchanger 20. While connecting the heat transfer pipe | tube 53 used as the flow path of a driving | operation, the lower part of the hot water storage tank 1 and the switching means 52 are connected with the hot water supply pipe | tube 21 via the heat pump apparatus 2. FIG.

  Furthermore, the upper part of the hot water tank 1 and the switching means 52 are connected by a boiling return pipe 54, and the bath heat recovery pump 25 is disposed in the bath return pipe 22.

  About the hot water supply apparatus comprised as mentioned above, the operation | movement and an effect | action are demonstrated below. The entire operation is the same as that described in the first embodiment, and a portion in which the hot water path differs depending on the circuit will be described.

  When performing a heat recovery operation in which the heat of the hot water in the bathtub 23 is recovered by the heat exchanger 20 into the hot water in the hot water storage tank 1, as shown in FIG. 9, the hot water in the bathtub 23 is transferred to the secondary side flow path of the heat exchanger 20. The bath circulation pump 26 is operated for transporting to the tank.

  Thereafter, from the lower part of the hot water tank 1, the hot water tank 1 in order from the bath outlet pipe 21, the heat pump device 2, the switching means 52, the primary flow path of the heat exchanger 20, the bath return pipe 22, and the substantially central part of the hot water tank 1. The bath heat recovery pump 25 is operated so that hot water from the water flows. Thereby, the heat which the hot water of the bathtub 23 has is collect | recovered by the hot water of the hot water tank 1.

  In addition, by making the conveyance amount of hot water by the bath circulation pump 26 larger than the conveyance amount of hot water by the bath heat recovery pump 25, the necessary flow rate by the bath circulation pump 26 is secured, and the temperature distribution in the bathtub 23 is made uniform. In addition to being able to stably recover heat from the bathtub 23, the transport flow rate by the bath heat recovery pump 25 becomes excessive, and the temperature stratification can be maintained without stirring the hot water in the hot water tank 1, It becomes possible to efficiently perform the boiling operation of hot water in the hot water tank 1 described later.

  Further, when a heating operation for heating the hot water in the hot water tank 1 is performed by the heat pump device 2, as shown in FIG. 10, the heat recovery operation control unit 32 sets the flow direction of the switching unit 52 as described above. By switching to a different direction and operating the pump provided in the bath outlet pipe 21, from the lower part of the hot water tank 1, the bath outlet pipe 21, the heat pump device 2, the switching means 52, the boiling return pipe 54, the hot water storage Hot water from the hot water tank 1 is flowed to the upper part of the tank 1 in order, and the amount of hot water conveyed by the pump provided in the bath outlet pipe 21 is controlled so that the hot water after passing through the heat pump device 2 reaches a predetermined boiling temperature. To do.

  Thereby, the water in the lower part of the hot water tank 1 is heated by the heat pump device 2 and returned to the upper part of the hot water tank 1, and the hot water is stored in the hot water tank 1.

  In the case of the heat recovery operation, the bath heat recovery pump 25 provided in the bath return pipe 22 is used to convey the hot water in the lower part of the hot water tank 1 to the primary side of the heat exchanger 20. A pump provided in the pipe 21 may be used.

  In this embodiment, since a considerable part of the flow path of the heat recovery operation and the boiling operation can be shared by using the switching means 52, the number of piping members to be used can be reduced, thus realizing resource saving and cost reduction. There is an effect that can be done.

As described above, since the hot water supply apparatus according to the present invention reduces the decrease in efficiency due to the use of the heat utilization terminal when using the heat of the hot water in the hot water storage tank, it can be applied to the domestic hot water supply apparatus as described above. In addition, the system having a heat source and a hot water storage tank can be applied to large-scale applications such as for business use and can provide excellent energy saving.

DESCRIPTION OF SYMBOLS 1 Hot water storage tank 1a-1e Hot water storage temperature detection means 2 Heating means (heat pump apparatus)
DESCRIPTION OF SYMBOLS 3 1st hot water pipe 4 2nd hot water pipe 5 Water supply pipe 6 1st mixing valve 7 2nd mixing valve 8 Hot water discharge pipe merge pipe 9 Mixed water pipe 10 Feed water branch pipe 11 Hot water outlet 12 Middle temperature detection means 13 Combined temperature detection Means 14 Hot water supply temperature detection means 15 Bath circulation circuit 16 Boiling pipe 20 Heat exchanger 21 Bath-out pipe 22 Bath return pipe (heat recovery return pipe)
23 Bath 24 Bath temperature detection means 25 Bath heat recovery pump 26 Bath circulation pump 30 Hot water supply temperature setting means 31 Hot water supply control means 32 Heat recovery operation control means 52 Switching means 53 Heat transfer pipe 54 Boiling return pipe

Claims (4)

A hot water storage tank, a first hot water pipe connected to the upper part of the hot water tank, a water supply pipe connected to the lower part of the hot water tank, and the first hot water pipe connected in the vertical direction of the hot water tank A second outlet pipe connected between a position and a position where the water supply pipe is connected; a bath outlet pipe connected to the hot water storage tank; and a heat of the bathtub hot water connected to the bath outlet pipe A heat exchanger to be recovered, a heat recovery return pipe connected to the heat exchanger and the hot water tank, and transporting the recovered heat from the heat exchanger to the hot water tank, and a heat pump for heating the hot water in the hot water tank and a device, after the hot water taken out from the hot water tank bottom was heated at the heat pump device, the water heater construction returned to the hot water tank top, the heat recovery return pipe, in the vertical direction of the hot water storage tank, The first tap pipe is connected to the hot water tank. Water heater, characterized in that connected to the hot water tank at a position between the position and a position where the second hot water pipe is connected to the hot water storage tank. The heat recovery operation by the heat exchanger is stopped so that an input at the time of the heating operation by the heat pump device after the heat recovery operation by the heat exchanger is substantially minimized. Water heater. As hot water heated by the heat Toponpu device returns to the hot water storage tank, and the boiling return pipe from the switching means connected to said hot water storage tank, and control means, wherein the bath往配tube, the hot water storage The hot water in the lower part of the tank is connected to the heat exchanger via the heat pump device and the switching means in order so that hot water in the lower part of the tank flows into the heat exchanger, and the heat of the hot water in the bathtub is obtained by the heat exchanger. When performing a heat recovery operation for recovering the hot water in the hot water tank, hot water from the hot water tank flows in the order of the bath outlet pipe, the heat pump device, the switching means, the heat exchanger, and the heat recovery return pipe. In addition, when performing a heating operation for heating the hot water in the hot water tank by the heat pump device, the bath outlet pipe, the heat pump device, the switching means, the boiling return pipe The way flow hot water from the hot water tank, water heater according to claim 1 or 2, characterized in that said control means has a configuration for switching the switching means to. The hot water supply apparatus according to any one of claims 1 to 3 , wherein the heat exchanger is a plate heat exchanger.

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