JP5862654B2 - Water heater - Google Patents

Description

  The present invention relates to a hot water supply apparatus.

  In the conventional hot water supply system, the temperature of the hot water in the lower part of the hot water tank rises due to the influence of the hot water in the upper part of the hot water tank, so the temperature sensor in the lower part of the hot water tank is higher than the actual hot water temperature. There is a problem that the accurate water supply temperature cannot be detected at the lower part of the hot water storage tank.

  Therefore, in order to solve such a problem, in a hot water supply apparatus having a hot water storage tank and a heat pump unit that circulates the hot water in the hot water storage tank through a boiling heat exchanger and heats it up, It has been proposed to detect the incoming water temperature of the boiling heat exchanger with an incoming water temperature sensor and to estimate the feed water temperature of water supplied from the outside into the hot water storage tank based on the incoming water temperature (for example, No. 2007-263396 (Patent Document 1)).

JP 2007-263396 A

  However, in such a hot water supply apparatus that estimates the feed water temperature based on the incoming water temperature, since the incoming water temperature sensor is provided in the heat pump unit, the pipe length between the heat pump unit and the hot water storage unit that houses the hot water storage tank is long. Then, there is a problem that the feed water temperature cannot be accurately estimated by the incoming water temperature sensor. In particular, when the above-described conventional hot water supply device is installed in a cold region, the heat pump unit boils in order to increase heat dissipation in the piping between the heat pump unit and the hot water storage unit, or to install a heat retaining heater for preventing freezing. The temperature of the water that enters the raised heat exchanger is greatly different from the water supply temperature.

  Then, the subject of this invention is providing the hot-water supply apparatus which can estimate a feed water temperature correctly based on the incoming water temperature of a boiling heat exchanger.

In order to solve the above problems, the hot water supply apparatus of the present invention is:
A boiling circuit connected to the upper part of the hot water storage tank through the boiling heat exchanger from the lower part of the hot water tank;
A circulation pump disposed in the boiling circuit;
An incoming water temperature sensor for detecting an incoming water temperature of the boiling heat exchanger;
The hot water storage tank, the boiling circuit including the boiling heat exchanger, the circulation pump, and a hot water storage unit that houses the incoming water temperature sensor;
When the hot water in the hot water storage tank is circulated by the circulation pump through the boiling circuit, the water supplied from the outside to the hot water storage tank is based on the incoming water temperature detected by the incoming water temperature sensor. A feed water temperature estimation unit for estimating a feed water temperature ;
Incoming water temperature storing a plurality of incoming water temperature data representing the incoming water temperature detected by the incoming water temperature sensor at intervals when the hot water in the hot water storage tank is circulated through the boiling circuit by the circulation pump. It includes a storage unit <br/>,
The water supply temperature estimation unit is characterized in that a minimum temperature among a plurality of water intake temperature data stored in the water input temperature storage unit in a preset estimation period is set as the water supply temperature .

According to the above configuration, the boiling heat exchanger and the incoming water temperature sensor are arranged in the hot water storage unit in which the hot water storage tank is accommodated, so that the hot water in the hot water storage tank is circulated by the circulation pump, for example, in the boiling operation or the freeze prevention operation. When circulating through the boiling circuit, based on the incoming water temperature detected by the incoming water temperature sensor, the feed water temperature estimating unit can accurately estimate the feed water temperature of water supplied from the outside into the hot water storage tank. It becomes possible. Therefore, regardless of the piping length from the boiling heat exchanger to the heat source (for example, heat pump unit), the feed water temperature can be accurately estimated based on the incoming water temperature of the boiling heat exchanger. In particular, by arranging the boiling heat exchanger and the incoming water temperature sensor directly below the hot water storage tank, the piping connecting the lower part of the hot water tank and the boiling heat exchanger can be shortened without routing, and the water supply temperature can be reduced. It can be estimated more accurately.
In addition, when circulating hot water in the hot water storage tank through the boiling circuit by the circulation pump, a plurality of incoming water temperature data representing the incoming water temperature detected by the incoming water temperature sensor are stored in the incoming water temperature storage unit at intervals. By setting the minimum temperature of the plurality of incoming water temperature data stored in the incoming water temperature storage unit during the estimation period as the feed water temperature by the feed water temperature estimation unit, for example, assuming the estimation period as one day, Since the temperature of the incoming water when the hot water is circulated through the boiling circuit by the circulation pump is set as the feed water temperature, an accurate feed water temperature can be obtained every day.
Moreover, the hot water supply apparatus of this invention is
A boiling circuit connected to the upper part of the hot water storage tank through the boiling heat exchanger from the lower part of the hot water tank;
A circulation pump disposed in the boiling circuit;
An incoming water temperature sensor for detecting an incoming water temperature of the boiling heat exchanger;
The hot water storage tank, the boiling circuit including the boiling heat exchanger, the circulation pump, and a hot water storage unit that houses the incoming water temperature sensor;
When the hot water in the hot water storage tank is circulated by the circulation pump through the boiling circuit, the water supplied from the outside to the hot water storage tank is based on the incoming water temperature detected by the incoming water temperature sensor. A feed water temperature estimation unit for estimating a feed water temperature;
A mixing valve for mixing hot water from the upper part of the hot water storage tank and hot water from the lower part of the hot water storage tank ,
The boiling circuit is connected from the lower part of the hot water storage tank to the upper part of the hot water storage tank via the mixing valve and the boiling heat exchanger,
When the opening of the lower side of the hot water storage tank of the mixing valve is fully open when the hot water in the hot water storage tank is circulated through the boiling circuit by the circulating pump, A water supply temperature of water supplied from the outside into the hot water storage tank is estimated based on an incoming water temperature detected by a temperature sensor .
According to the above configuration, the boiling heat exchanger and the incoming water temperature sensor are arranged in the hot water storage unit in which the hot water storage tank is accommodated, so that the hot water in the hot water storage tank is circulated by the circulation pump, for example, in the boiling operation or the freeze prevention operation. When circulating through the boiling circuit, based on the incoming water temperature detected by the incoming water temperature sensor, the feed water temperature estimating unit can accurately estimate the feed water temperature of water supplied from the outside into the hot water storage tank. It becomes possible. Therefore, regardless of the piping length from the boiling heat exchanger to the heat source (for example, heat pump unit), the feed water temperature can be accurately estimated based on the incoming water temperature of the boiling heat exchanger. In particular, by arranging the boiling heat exchanger and the incoming water temperature sensor directly below the hot water storage tank, the piping connecting the lower part of the hot water tank and the boiling heat exchanger can be shortened without routing, and the water supply temperature can be reduced. It can be estimated more accurately.
In addition, when circulating hot water in the hot water storage tank through the boiling circuit by the circulation pump, hot water from the lower part of the hot water storage tank and hot water from the upper part of the hot water storage tank are mixed by the mixing valve. It becomes possible to boil the medium temperature water. However, since the water temperature of the mixed water by the mixing valve is higher than that of the water below the hot water storage tank, the water supply temperature cannot be estimated. Therefore, when the hot water in the hot water storage tank is circulated through the boiling circuit by the circulation pump, when the opening of the lower side of the hot water storage tank of the mixing valve is fully open, that is, the hot water in the lower and upper parts of the hot water storage tank is mixed. When not mixed by the valve, the hot water temperature is estimated accurately by estimating the feed water temperature of water supplied from the outside into the hot water storage tank by the feed water temperature estimation unit based on the incoming water temperature detected by the incoming water temperature sensor. it can.

Moreover, in the hot water supply apparatus of one embodiment,
When the hot water in the hot water storage tank is circulated through the boiling circuit by the circulation pump, the water supply temperature estimation unit is configured to perform the input after a predetermined non-detection time has elapsed from the start of operation of the circulation pump. Based on the incoming water temperature detected by the water temperature sensor, the supply temperature of the water supplied from the outside into the hot water storage tank is estimated.

  According to the embodiment, when the hot water in the hot water storage tank is circulated through the boiling circuit by the circulation pump, the feed water temperature estimation unit is after the preset non-detection time has elapsed from the start of the operation of the circulation pump. Based on the incoming water temperature detected by the incoming water temperature sensor, the water supply temperature of the water supplied from the outside into the hot water storage tank is estimated. By setting this preset time longer than the time from the start of the circulation pump operation until the water in the lower part of the hot water tank reaches the detection position of the incoming water temperature sensor, the hot water storage tank immediately before the start of the circulation pump operation is set. Without detecting the temperature of the water in the pipe from the lower part of the water to the incoming water temperature sensor, the temperature of the water can be detected after the water in the lower part of the hot water tank reaches the detection position of the incoming water temperature sensor, and the incoming water temperature is more accurate. Can be detected.

Moreover, in the hot water supply apparatus of one embodiment,
The preset non-detection time is determined based on the pipe length from the lower part of the hot water storage tank to the incoming water temperature sensor.

  According to the embodiment, the preset non-detection time is determined based on the pipe length from the lower part of the hot water storage tank to the incoming water temperature sensor. That is, by setting the non-detection time to be long or short according to the length of the pipe, the temperature of water in the pipe from the bottom of the hot water storage tank immediately before the start of the circulation pump to the detection position of the incoming water temperature sensor is set. It becomes possible not to detect.

Moreover, in the hot water supply apparatus of one embodiment,
When the temperature rise of the feed water temperature obtained in the current estimation period is equal to or higher than a preset temperature with respect to the feed water temperature obtained in the previous estimation period, The sum of the obtained feed water temperature and the preset temperature is set as the feed water temperature in the current estimation period.

  According to the above embodiment, when the temperature increase of the feed water temperature obtained in the current estimation period is equal to or higher than a preset temperature with respect to the feed water temperature obtained in the previous estimation period, the feed water temperature estimation unit The sum of the feed water temperature and the preset temperature is set as the feed water temperature in the current estimation period. As a result, since the hot water in the hot water storage tank is not used and the hot water temperature in the lower part of the hot water storage tank becomes high and greatly differs from the water supply temperature of the water supplied from the outside, the previous water supply temperature is preset. The sum of the temperatures can be used as the feed water temperature in the current estimation period so that the wrong feed water temperature is not used.

Moreover, in the hot water supply apparatus of one embodiment,
When the temperature rise of the feed water temperature obtained in the current estimation period is equal to or higher than a preset temperature with respect to the feed water temperature obtained in the previous estimation period, Let the obtained water supply temperature be the water supply temperature in the said estimation period this time.

  According to the above embodiment, when the temperature rise of the feed water temperature obtained in the current estimation period is equal to or higher than a preset temperature with respect to the feed water temperature obtained in the previous estimation period, the feed water temperature estimation unit performs the previous time. The feed water temperature is the feed water temperature in this estimation period. As a result, the hot water in the hot water storage tank is not used, so if the hot water temperature in the lower part of the hot water tank is high and greatly differs from the water supply temperature of the water supplied from the outside, the previous water supply temperature is estimated as it is. It can be used as the feed water temperature in the period so that the wrong feed water temperature is not used.

Moreover, in the hot water supply apparatus of one embodiment,
With respect to the feed water temperature estimated by the feed water temperature estimation unit, the temperature rise due to hot water mixed from the upper side of the hot water storage tank is removed when the opening degree on the lower side of the hot water storage tank is the fully open valve. The water supply temperature correction part which correct | amends as follows was provided.

  According to the above-described embodiment, even if the opening degree of the lower side of the hot water storage tank of the mixing valve is fully open, about 1% of hot water is mixed into the mixing valve from the upper part of the hot water storage tank. The feed water temperature becomes high. Therefore, the feed water temperature correction unit is configured to mix the valve when the opening on the lower side of the hot water storage tank is fully open with respect to the feed water temperature estimated by the feed water temperature estimation unit based on the incoming water temperature detected by the incoming water temperature sensor. By correcting so as to exclude the temperature rise due to hot water mixed in from the upper side of the hot water storage tank, a more accurate water supply temperature can be estimated.

Moreover, in the hot water supply apparatus of one embodiment,
The said feed water temperature correction | amendment part correct | amends the said feed water temperature estimated by the said feed water temperature estimation part based on the water temperature of the upper part in the said hot water storage tank.

  According to the embodiment, based on the water temperature in the upper part of the hot water storage tank, the water supply temperature estimated by the water supply temperature estimation unit is corrected by the water supply temperature correction unit, whereby a more accurate water supply temperature can be estimated.

  As apparent from the above, according to the present invention, a boiling heat exchanger and an incoming water temperature sensor are arranged in the hot water storage unit in which the hot water storage tank is accommodated, and the hot water in the hot water storage tank is heated by a circulation pump. Water supply based on the incoming water temperature of the boiling heat exchanger by estimating the water supply temperature of the water supplied from the outside into the hot water storage tank based on the incoming water temperature detected by the incoming water temperature sensor when circulating through A hot water supply apparatus capable of accurately estimating the temperature can be realized.

FIG. 1 is a schematic diagram showing a configuration of a heat pump type hot water supply apparatus according to an embodiment of the present invention. FIG. 2 is a piping system diagram of the hot water supply apparatus. FIG. 3 is a control block diagram of the hot water supply apparatus.

  Hereinafter, a hot water supply apparatus of the present invention will be described in detail with reference to embodiments shown in the drawings.

  FIG. 1 shows the configuration of a heat pump type hot water supply apparatus according to an embodiment of the present invention.

  As shown in FIG. 1, the hot water supply apparatus of this embodiment includes a hot water storage unit 1 and a heat pump unit 2 connected to the hot water storage unit 1. The hot water storage unit 1 includes a hot water storage tank 3, a boiling heat exchanger 10 disposed immediately below the hot water storage tank 3, a reheating heat exchanger 20 (shown in FIG. 2), and a control device 100 (shown in FIG. 3). Etc.). A temperature sensor T11 for detecting the incoming water temperature is provided on the upstream side of the boiling heat exchanger 10, and a temperature sensor T12 for detecting the tapping temperature is provided on the downstream side of the boiling heat exchanger 10.

  FIG. 2 shows a piping system diagram of the hot water supply apparatus.

  As shown in FIG. 2, one end of a pipe L1 is connected to the lower part of the hot water storage tank 3, and the other end of the pipe L1 is connected to a first water inlet port of a boiling mixing valve 50 as an example of a mixing valve. One end of the pipe L <b> 2 is connected to the water outlet port of the boiling mixing valve 50, and the other end of the pipe L <b> 2 is connected to one end of the boiling heat exchanger 10. The other end of the boiling heat exchanger 10 is connected to one end of the pipe L3, and the other end of the pipe L3 is connected to a return port 3a provided in the upper part of the hot water storage tank 3. A boiling circulation pump P1 as an example of a circulation pump is disposed in the pipe L2. Further, a rectifying plate 70 is provided in the hot water storage tank 3 and in the vicinity of the return port 3a to suppress the flow toward the hot water outlet 3b provided in the upper part of the hot water storage tank 3.

  The piping L1, the piping L2, the boiling heat exchanger 10, and the piping L3 constitute a boiling circuit.

  The hot water in the hot water storage tank 3 is supplied to the pipe L1 by driving the boiling circulation pump P1 with the opening degree of the first mixing port 50 (hot water storage tank 3 side) of the boiling mixing valve 50 fully opened. , Circulating through the mixing valve 50 for boiling, the pipe L2, the boiling heat exchanger 10, and the pipe L3.

  The boiling heat exchanger 10 is connected to the heat pump unit 2 via refrigerant pipes L4 and L5. The heat pump unit 2 uses an HFC refrigerant, and can control the temperature of the hot water from the boiling heat exchanger 10 in a range of, for example, 50 ° C to 70 ° C. Examples of the HFC refrigerant used in the heat pump unit 2 include R32, R125, R134a, R404A, R410A, and R407C.

  Next, an external water supply pipe is connected to the lower part of the hot water storage tank 3 through a pipe L11. A pressure reducing valve 11 and a check valve 12 are arranged in this pipe L11 in order from the upstream side. This check valve 12 allows only the flow from the water supply pipe side to the hot water storage tank 3 side.

  In addition, one end of the pipe L21 is connected to the hot water outlet 3b provided in the upper part of the hot water storage tank 3, and the other end of the pipe L21 is connected to the primary water inlet port of the heat exchanger 20. One end of the pipe L22 is connected to the primary water outlet port of the reheating heat exchanger 20, and the other end of the pipe L22 is connected to the second water inlet port of the boiling mixing valve 50.

  The pipe L21, the reheating heat exchanger 20, and the line L22 constitute a bath reheating circuit.

  The hot water in the upper part of the hot water storage tank 3 is removed by driving the circulating pump P1 for boiling while the opening degree of the second mixing port 50 (the bath reheating circuit side) of the boiling mixing valve 50 is fully opened. And circulating through the pipe L21, the reheating heat exchanger 20 (primary side), the pipe L22, the boiling mixing valve 50, the pipe L2, and the boiling heat exchanger 10 pipe L3.

  Further, one end of the pipe L31 is connected to the upper part of the hot water storage tank 3, and the other end of the pipe L31 is connected to the first water inlet port of the hot water supply mixing valve 22. A check valve 21 that allows only a flow from the hot water storage tank 3 side to the hot water supply mixing valve 22 is disposed in the pipe L31. One end of the branch pipe L12 is connected to the second water inlet port of the hot water supply mixing valve 22, and the other end of the branch pipe L12 is connected between the pressure reducing valve 11 and the check valve 12 of the pipe L11. The branch pipe L12 is provided with a check valve 23 that allows only the flow from the pipe L11 side to the hot water supply mixing valve 22.

  One end of the pipe L32 is connected to the water outlet port of the hot water supply mixing valve 22, and the other end of the pipe L32 is connected to the hot water tap 60 (a faucet in this embodiment). A water amount sensor 24 is disposed in the pipe L32.

  The branch pipe L12, the pipe L31, the pipe L32, the check valve 21, the hot water supply mixing valve 22, the check valve 23, and the water amount sensor 24 constitute a hot water supply circuit.

  One end of the pipe L33 is connected to the upstream side of the water amount sensor 24 of the pipe L32, and the other end of the pipe L33 is connected to the hot water supply port 9a of the connection adapter 9 provided in the bathtub 4. A hot water filling solenoid valve 25, a check valve 26, a water amount sensor 27, and a check valve 28 are arranged in this order from the upstream side of the pipe L33. These check valves 26 and 28 allow only the flow from the hot water supply mixing valve 22 side to the bathtub 4.

  The pipe L33, the hot water solenoid valve 25, the check valves 26 and 28, and the water amount sensor 27 constitute a bath hot water supply circuit branched from the hot water supply pipe L32 and connected to the bathtub 4.

  One end of the pipe L35 is connected to the water intake port 9b for replenishment of the connection adapter 9, and the other end of the pipe L35 is connected to the water inlet port on the secondary side of the heat exchanger 20. A circulation pump P2 for bath is disposed in the pipe L35. Further, one end of the pipe L34 is connected to the downstream side of the water amount sensor 27 of the pipe L33, and the other end of the pipe L34 is connected to the secondary water outlet port of the heat exchanger 20.

  The hot water in the bathtub 4 is circulated through the pipe L35, the reheating heat exchanger 20 (secondary side), the pipe L34, and the pipe L33 (part) by the bath circulation pump P2.

  The pipe L35, the reheating heat exchanger 20 (secondary side), the pipe L34, and the pipe L33 (part) constitute a bath circulation circuit.

  Furthermore, one end of the pipe L41 is connected to the pipe L21, and the other end of the pipe L41 is connected to the drain port. A relief valve 31 is provided in the pipe L41.

  The hot water storage tank 3 is provided with four temperature sensors T1 to T4 at substantially equal intervals from the lower side to the upper side. In addition, a temperature sensor T11 for detecting the incoming water temperature is provided in the pipe L2, and a temperature sensor T12 for detecting the hot water temperature is provided in the pipe L3. The temperature sensor T11 is an example of an incoming water temperature sensor, and the temperature sensor T12 is an example of a hot water temperature sensor.

  Further, the boiling heat exchanger 10 is provided with a temperature sensor T13. In addition, a temperature sensor T <b> 21 for detecting a hot water supply temperature is provided in the pipe L <b> 32 connected to the hot water tap 60 on the downstream side of the water amount sensor 24. In addition, a water level sensor LS, a water flow switch SW, and a temperature sensor T23 are connected to the pipe L35 connected to the bathtub 4 from the connection adapter 9 side between the connection adapter 9 on the bathtub 4 side and the circulation pump P2 for bath. In order. Furthermore, a temperature sensor T22 that detects the temperature of hot water supplied to the bathtub 4 is provided downstream of the check valve 28 of the pipe L33 connected to the bathtub 4 and at a connection point between the pipe L33 and the pipe L34. Yes.

  As shown in FIG. 3, the hot water supply device includes a control device 100 including a microcomputer and an input / output circuit, and a remote controller 200 that transmits and receives signals to and from the control device 100. The control device 100 includes signals from temperature sensors T1 to T4, T11 to T13, T21 to T23, a water level sensor LS, a water flow switch SW, water volume sensors 24 and 27, an outside air temperature sensor (not shown), a remote controller 200, and the like. In response, the heat pump unit 2, the boiling circulation pump P1, the bath circulation pump P2, the hot water mixing valve 22, the hot water solenoid valve 25, the boiling mixing valve 50, and the like are controlled.

  Further, the control device 100 includes a boiling control unit 100a that controls an operation of boiling hot water in the hot water storage tank 3, a hot water supply control unit 100b that controls a hot water supply temperature to the hot water tap 60, and a “bath hot water operation”. For example, a pouring control unit 100c for controlling the pouring operation to the bathtub 4 including the above, a reheating control unit 100d for controlling the "bath chasing operation", and the water supply temperature of the water supplied into the hot water storage tank 3 from the outside A water supply temperature estimation unit 100e for estimating the water supply temperature, an incoming water temperature storage unit 100f for storing a plurality of incoming water temperature data representing the incoming water temperature, and a water supply temperature correction unit 100g for correcting the water supply temperature estimated by the water supply temperature estimation unit 100e. .

  In the hot water supply apparatus configured as described above, the hot water supply control unit 100b controls the mixing ratio of the hot water supply mixing valve 22 so that the hot water supply temperature detected by the temperature sensor T21 becomes the hot water supply set temperature.

<Boiling operation>
In the “boiling operation” in which hot water in the hot water storage tank 3 is boiled by the heat pump unit 2, the boiling control unit 100 a of the control device 100 causes the first mixing port 50 side of the boiling mixing valve 50 (hot water storage tank 3 side). The boiling circulation pump P1 is operated with the opening of the valve fully opened, and the hot water in the hot water storage tank 3 is connected to the pipe L1, the boiling mixing valve 50, the pipe L2, the boiling heat exchanger 10, and the pipe L3. Circulate through.

  The boiling control unit 100a controls the opening degree of the mixing valve 50 for boiling during the heating operation, and the heat pump unit 2 so that the hot water temperature detected by the temperature sensor T12 becomes the target hot water temperature TS. The boiling circulation pump P1 is controlled. Here, the target hot water temperature TS is calculated by the control device 100 based on the amount of hot water supplied from the hot water storage tank 3 and the like. For example, when the amount of hot water used is large, the target hot water temperature TS is as high as 70 ° C., for example, and when the amount of hot water used is small, the target hot water temperature TS is as low as 50 ° C., for example.

  Then, when the incoming water temperature of the boiling heat exchanger 10 detected by the temperature sensor T11 reaches 40 ° C. to 45 ° C. (boiling end temperature), the boiling operation is finished.

<Bath bathing operation>
Next, when performing a “bath hot water filling operation” in which hot water is supplied from the hot water storage tank 3 into the bath tub 4, the hot water filling electromagnetic valve 25 is opened by the hot water injection controller 100 c of the control device 100, and the hot water storage tank 3 is filled. Is supplied into the bathtub 4 through the hot water mixing valve 22 and the bath hot water supply circuit (L33, 25, 26, 27, 28). At this time, the hot water pouring control unit 100c controls the hot water supply mixing valve 22 to mix the hot water from the hot water storage tank 3 and the external water supply based on the target set temperature, and the water level sensor LS. When the detected water level in the bathtub 4 reaches the set water level, the hot water solenoid valve 25 is closed.

<Bath chasing operation>
Next, when performing “bath chasing operation” for chasing hot water in the bath tub 4 from the hot water storage tank 3, the hot water filling electromagnetic valve 25 is closed by the chasing control unit 100d of the control device 100. Then, the bath circulation pump P2 is operated to circulate the hot water in the bathtub 4 through the pipe L35, the reheating heat exchanger 20 (secondary side), the pipe L34, and the pipe L33 (part).

  Then, based on the bath temperature of the hot water in the bathtub 4 detected by the temperature sensor T23, the reheating controller 100d performs a reheating operation using the hot water in the hot water storage tank 3 as a heat source without using the heat pump unit 2. Or when the amount of heat in the hot water storage tank 3 is not sufficient, the bath pumping operation is performed using the heat pump unit 2.

  In the bath reheating operation using the heat pump unit 2, the hot water from the boiling heat exchanger 10 is recirculated with the hot water tank 3, the boiling circuit (L 1, L 2, 10, L 3) and the bath reheating with the circulation pump P 1. Circulate through the circuit (L21, 20, L22) to retreat the bath.

<Anti-freezing operation>
In order to prevent the pipes L1 and L2 below the hot water storage tank 3 from freezing, the boiling circulation pump P1 is operated to supply hot water in the hot water storage tank 3 to the pipe L1, the boiling mixing valve 50, and the pipe L2. Then, it is circulated through the boiling heat exchanger 10 and the pipe L3 (the heat pump unit 2 is not operated). This anti-freezing operation is started when the incoming water temperature detected by the temperature sensor T11 falls to 2 ° C., for example, and is ended when the incoming water temperature becomes 5 ° C.

According to the hot water supply apparatus having the above-described configuration, the boiling heat exchanger 10 and the temperature sensor T11 that is the incoming water temperature sensor are disposed in the hot water storage unit 1 in which the hot water storage tank 3 is accommodated. based on the detected incoming water temperature, the water temperature estimating unit 100 e, it is possible to accurately estimate the water temperature T _W of the water supplied from an external water supply pipe to the hot water storage tank 3. Therefore, regardless of the pipe length from the boiling heat exchanger 10 to the heat pump unit 2 can accurately estimate the water temperature T _W, based on the incoming water temperature of the water heating heat exchanger 10. In particular, by disposing the boiling heat exchanger 10 and the temperature sensor T11 directly below the hot water storage tank 3, it is possible to shorten the piping without connecting the pipe connecting the lower portion of the hot water storage tank 3 and the boiling heat exchanger 10. , it is possible to more accurately estimate the water temperature T _W. The feed water temperature T _W is used for a control of the heating operation.

In the boiling operation, the feed water temperature estimation unit 100e is based on the incoming water temperature detected by the temperature sensor T11 (incoming water temperature sensor) after a predetermined non-detection time has elapsed from the start of the operation of the boiling circulation pump P1. Te, estimates the feedwater temperature T _W of the water supplied from an external water supply pipe to the hot water storage tank 3. The predetermined non-detection time is set longer than the time from the start of the operation of the boiling circulation pump P1 to the time when the water in the lower part of the hot water storage tank 3 reaches the detection position of the temperature sensor T11. Without detecting the temperature of the water in the pipe from the bottom of the hot water storage tank 3 immediately before the start of the operation of the pump P1 to the detection position of the temperature sensor T11, the water in the lower part of the hot water storage tank 3 reaches the detection position of the temperature sensor T11. The temperature of the water can be detected after that, and the incoming water temperature can be detected more accurately.

  Further, the non-detection time is determined based on the pipe length from the lower part of the hot water storage tank 3 to the temperature sensor T11 (incoming water temperature sensor), so that the lower part of the hot water storage tank 3 immediately before the start of the operation of the boiling circulation pump P1. It is possible not to detect the temperature of the water in the pipe from the detection position to the detection position of the temperature sensor T11.

In addition, a plurality of incoming water temperature data representing the incoming water temperature detected by the temperature sensor T11 (incoming water temperature sensor) is stored in the incoming water temperature storage unit 100f at intervals (for example, 5 minutes) during the boiling operation, and the water supply temperature is stored. the estimation unit 100 e, by the minimum temperature of the plurality of incoming water temperature data stored in the incoming water temperature storage unit 100f during heating operation in 1 day (estimated period) and feedwater temperature T _W, boiling in 1 day since the lowest temperature incoming water temperature during up operation is to feed water temperature T _W, an accurate water temperature T _W is obtained per day.

  In this embodiment, a plurality of incoming water temperature data representing the incoming water temperature detected by the temperature sensor T11 (incoming water temperature sensor) is stored in the incoming water temperature storage unit 100f. However, the incoming water temperature detected last time and the incoming water detected this time are stored. The temperature may be compared and only the lower one stored in the incoming water temperature storage unit 100f may be repeated.

  In addition, although the said "estimated period" was 1 day, it may be several days, for example, and may be one heating operation period.

In addition, with respect to the water supply temperature T _W1 obtained on the previous day (previous estimation period), the temperature rise value (T _W2 −T _W1 ) of the water supply temperature T _W2 obtained on that day (current estimation period) is a predetermined temperature ( For example, when the temperature is equal to or higher than 2 ° C., the sum of the previous day's water temperature and the predetermined temperature (for example, 2 ° C.) is set as the water temperature on the current day (current estimation period) by the water temperature estimation unit 100e. As a result, since the hot water in the hot water storage tank 3 is not used, the hot water temperature in the lower part of the hot water storage tank 3 becomes high and greatly differs from the water supply temperature of the water supplied from the external water supply pipe. The sum of T _W1 and the predetermined temperature can be used as the water supply temperature for the day, so that the wrong water supply temperature is not used.

Alternatively, the temperature rise value (T _W2 −T _W1 ) of the water supply temperature _TW2 obtained on the current day (current estimation period) is a predetermined temperature with respect to the water supply temperature _TW1 obtained on the previous day (previous estimation period). When the temperature is equal to or higher than (eg, 2 ° C.), the water supply temperature estimation unit 100e sets the water supply temperature T _{W1 of the} previous day as the water supply temperature on the day. As a result, since the hot water in the hot water storage tank 3 is not used, the hot water temperature in the lower part of the hot water storage tank 3 becomes high and greatly differs from the water supply temperature of the water supplied from the external water supply pipe. _TW1 can be used as it is as the water supply temperature for the current day (the current estimation period) without using an incorrect water supply temperature.

Further, during the boiling operation, the hot water from the lower part of the hot water storage tank 3 and the hot water from the upper part of the hot water storage tank 3 are mixed by the boiling mixing valve 50 to boil the medium temperature water in the hot water storage tank 3. It becomes possible. However, since the water temperature of the mixed water by the boiling mixing valve 50 is higher than that of the hot water in the lower part of the hot water storage tank 3, the water supply temperature cannot be estimated. Therefore, when the opening on the lower side of the hot water storage tank 3 of the boiling mixing valve 50 is fully opened in the boiling operation, that is, when the hot water in the lower and upper portions of the hot water storage tank 3 is not mixed by the boiling mixing valve 50, based on the incoming water temperature detected by the temperature sensor T11 (incoming water temperature sensor), the feedwater temperature estimating unit 100 e, by estimating the feedwater temperature T _W of the water supplied from an external water supply pipe to the hot water storage tank 3, Accurate water supply temperature can be estimated.

Even if the opening of the lower side of the hot water storage tank 3 of the mixing valve 50 for boiling is fully open, about 1% of hot water is mixed into the mixing valve 50 for boiling from the upper part of the hot water storage tank 3, so that the water supply temperature feedwater temperature _{T W} estimated by the estimation unit 100e increases. Therefore, the water feed temperature correction unit 100g, to the feedwater temperature T _W estimated by the feed water temperature estimating unit 100 e, the lower side of the hot water storage tank 3 opening of the hot water storage tank 3 for mixing valve 50 for boiling the fully opened By correcting so as to remove the temperature rise due to mixing of hot water from the top, a more accurate water supply temperature can be estimated.

  The feed water temperature correction unit 100g corrects the feed water temperature estimated by the feed water temperature estimation unit 100e based on the water temperature in the upper part of the hot water storage tank 3.

The correction excluding the temperature rise by the feed water temperature correction unit 100g is performed as follows.
First, the boiling flow rate is
Boiling flow rate = Slope × Number of rotations of the circulating pump P1 for boiling. The inclination is a value determined by the pipe resistance and is determined in advance. When the mixing ratio of hot water from the upper part of the hot water storage tank 3 in the boiling mixing valve 50 is 1% and the water temperature T _TOP in the upper part of the hot water storage tank 3 detected by the temperature sensor T4 is set, the mixing valve 50 for boiling is added. The amount of heat mixed from the top of the hot water storage tank 3 is
Amount of heat = boiling flow rate x 0.01 x T _TOP
It can be calculated by, determining the corrected temperature T _F corresponding to the amount of heat obtained by the above formula, by subtracting the correction temperature T _F from the water temperature T _W estimated by the feed water temperature estimating unit 100 e, the water supply after the correction The temperature (T _W −T _F ) is obtained.

  The estimation of the feed water temperature is performed at the time of boiling operation, but may be performed at the time of anti-freezing operation in which the hot water in the hot water storage tank 3 is circulated in the boiling circuit without operating the heat pump unit 2.

  Further, the hot water is stored in the hot water storage unit 1 which accommodates the hot water storage tank 3, the heating mixing valve 50, the bath reheating circuit (L21, 20, L22), the heating circuit (L1, L2, 10, L3) and the like. By arranging the exchanger 10, compared with the case where the boiling heat exchanger 10 is built in the heat pump unit 2 side, the heat dissipation of the hot water in the pipe between the heat pump unit 2 and the hot water storage unit 1 is reduced. The hot water in the hot water storage tank 3 can be boiled efficiently.

  In the above embodiment, the hot water supply apparatus using the heat pump unit 2 as a heat source has been described. However, the heat source is not limited to this, and a hot water supply apparatus that boils hot water in the hot water storage tank with another heat source such as a boiler may be used.

Further, in the above embodiment, using HFC refrigerant heat pump unit 2 is not limited to this refrigerant used in the heat pump unit, it may be used CO ₂ refrigerant or other coolant.

For example, by using a CO ₂ refrigerant in the heat pump unit, it is possible to control the hot water temperature in a high temperature range (for example, 65 ° C. to 90 ° C.).

  Moreover, in the said embodiment, although the hot water supply apparatus which connected the upper part of the hot water storage tank 3 to the inflow side of the mixing valve 50 for boiling through the bath reheating circuit was demonstrated, the upper part of the hot water storage tank is connected to another circuit for mixing. You may apply this invention to the hot-water supply apparatus connected to the inflow side of the mixing valve through this.

  Further, in the above embodiment, the hot water supply device that controls the opening degree of the mixing valve 50 for boiling during the boiling operation and mixes the hot water in the upper and lower parts of the hot water storage tank 3 to be heated up has been described. You may apply this invention to the hot-water supply apparatus which boils without mixing the hot water of the upper part and lower part in a hot water storage tank by a mixing valve at the time of a boiling operation.

  Although specific embodiments of the present invention have been described, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Hot water storage unit 2 ... Heat pump unit 3 ... Hot water storage tank 3a ... Return port 3b ... Outlet 4 ... Bathtub 9 ... Connection adapter 9a ... Hot water supply port 9b ... Water intake 10 for boiling water 10 ... Boiling heat exchanger 11 ... Pressure reducing valve 12 , 21, 23, 26, 28 ... Check valve 20 ... Reheating heat exchanger 22 ... Mixing valve for hot water supply 24, 27 ... Water volume sensor 25 ... Solenoid valve for hot water filling 31 ... Relief valve 50 ... Mixing valve for boiling 60 ... Hot water tap 70 ... Rectifying plate 100 ... Control device 100a ... Boiling control unit 100b ... Hot water supply control unit 100c ... Pouring hot water control unit 100d ... Reheating control unit 100e ... Water supply temperature estimation unit 100f ... Water temperature storage unit 100g ... Water supply temperature Correction unit 200 ... Remote controller L1, L2, L3, L11, L21, L22, L31 to L35, L41 ... Piping L4, L5 ... Refrigerant piping L12 ... Branch piping LS ... Water level sensor P1 ... Boiling For raising the circulation pump P2 ... for the bath circulation pump SW ... water flow switch T1~T4, T11~T13, T21~T23 ... temperature sensor

Claims (8)

A boiling circuit (L1, L2, 10, L3) connected to the upper part of the hot water storage tank (3) from the lower part of the hot water storage tank (3) via the boiling heat exchanger (10);
A circulation pump (P1) disposed in the boiling circuit (L1, L2, 10, L3);
An incoming water temperature sensor (T11) for detecting an incoming water temperature of the boiling heat exchanger (10);
The hot water storage tank (3), the boiling circuit (L1, L2, 10, L3) including the boiling heat exchanger (10), the circulation pump (P1), and the incoming water temperature sensor (T11) A hot water storage unit (1) for housing
When the hot water in the hot water storage tank (3) is circulated through the boiling circuit (L1, L2, 10, L3) by the circulation pump (P1), it is detected by the incoming water temperature sensor (T11). A water supply temperature estimating unit (100e) for estimating a water supply temperature of water supplied from the outside into the hot water storage tank (3) based on the incoming water temperature ;
When the hot water in the hot water storage tank (3) is circulated through the boiling circuit (L1, L2, 10, L3) by the circulation pump (P1), the incoming water temperature sensor (T11) is spaced apart. comprising a <br/> the incoming water temperature storage unit for storing a plurality of incoming water temperature data representative of the detected entering water temperature (100f) by,
The water supply temperature estimation unit (100e) uses, as the water supply temperature, the lowest temperature among the plurality of water intake temperature data stored in the water input temperature storage unit (100f) during a preset estimation period. Hot water supply device. A boiling circuit (L1, L2, 10, L3) connected to the upper part of the hot water storage tank (3) from the lower part of the hot water storage tank (3) via the boiling heat exchanger (10);
A circulation pump (P1) disposed in the boiling circuit (L1, L2, 10, L3);
An incoming water temperature sensor (T11) for detecting an incoming water temperature of the boiling heat exchanger (10);
The hot water storage tank (3), the boiling circuit (L1, L2, 10, L3) including the boiling heat exchanger (10), the circulation pump (P1), and the incoming water temperature sensor (T11) A hot water storage unit (1) for housing
When the hot water in the hot water storage tank (3) is circulated through the boiling circuit (L1, L2, 10, L3) by the circulation pump (P1), it is detected by the incoming water temperature sensor (T11). A water supply temperature estimating unit (100e) for estimating a water supply temperature of water supplied from the outside into the hot water storage tank (3) based on the incoming water temperature;
A mixing valve (50) for mixing hot water from the upper part of the hot water storage tank (3) and hot water from the lower part of the hot water storage tank (3) ;
The boiling circuit (L1, L2, 10, L3) is connected to the hot water storage tank (3) from the lower part of the hot water storage tank (3) via the mixing valve (50) and the boiling heat exchanger (10). Connected to the top,
The water supply temperature estimating unit (100e) is configured to circulate the hot water in the hot water storage tank (3) through the boiling circuit (L1, L2, 10, L3) by the circulation pump (P1). When the opening of the lower side of the hot water storage tank (3) of (50) is fully open, the hot water storage tank (3) is supplied from the outside based on the incoming water temperature detected by the incoming water temperature sensor (T11). A hot water supply apparatus for estimating a water supply temperature of water to be discharged. The hot water supply apparatus according to claim 2,
When the opening on the lower side of the hot water storage tank (3) is fully open with respect to the water temperature estimated by the water supply temperature estimation unit (100e), the hot water storage tank (3) of the mixing valve (50) is fully opened. A hot water supply apparatus comprising a water supply temperature correction unit (100 g) for correcting so as to exclude a temperature increase due to hot water mixed from the upper side. The hot water supply apparatus according to claim 3,
The water supply temperature correction unit (100g) corrects the water supply temperature estimated by the water supply temperature estimation unit (100e) based on the water temperature in the upper part of the hot water storage tank (3). . In the hot water supply device according to any one of claims 1 to 4 ,
The water supply temperature estimation unit (100e) circulates the hot water in the hot water storage tank (3) when the hot water in the hot water storage tank (3) is circulated through the boiling circuit (L1, L2, 10, L3) by the circulation pump (P1). Based on the incoming water temperature detected by the incoming water temperature sensor (T11) after elapse of a preset non-detection time from the start of operation of the pump (P1), the hot water storage tank (3) is supplied from the outside. A hot water supply apparatus for estimating a water supply temperature of water. The hot water supply apparatus according to claim 5 ,
The preset non-detection time is determined based on a pipe length from a lower part of the hot water storage tank (3) to the incoming water temperature sensor (T11). The hot water supply apparatus according to claim 1 ,
When the temperature rise of the feed water temperature obtained in the current estimation period is equal to or higher than a preset temperature with respect to the feed water temperature obtained in the previous estimation period, the feed water temperature estimation unit (100e) A hot water supply apparatus characterized in that a sum of a water supply temperature obtained in an estimation period and the preset temperature is set as a water supply temperature in the current estimation period. The hot water supply apparatus according to claim 1 ,
When the temperature rise of the feed water temperature obtained in the current estimation period is equal to or higher than a preset temperature with respect to the feed water temperature obtained in the previous estimation period, the feed water temperature estimation unit (100e) A hot water supply apparatus characterized in that a feed water temperature obtained in an estimation period is set as a feed water temperature in the current estimation period.

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