JP2023132498A - water heater - Google Patents

Abstract

To provide a water heater capable of improving boiling-up efficiency when performing a boiling-up operation in a daytime zone and a night time zone.SOLUTION: A water heater includes, as stored hot water temperature detecting means 18a detecting temperatures of hot water in the hot water storing tank 10: a first stored hot water temperature detecting means 18ad detecting a lower part hot water temperature in a hot water storing tank 10; and a second stored hot water temperature detecting means 18au detecting an upper part hot water temperature at a position higher than the first stored hot water detecting means 18ad. A control device 30 detects the lower part hot water temperature by the first stored hot water temperature detecting means 18ad in a daytime zone mode 31A, and meanwhile, detects the upper part hot water temperature by the second stored hot water temperature detecting means 18au in a night time zone mode 31B, and finishes a boiling-up operation in the daytime zone mode 31A in a state where the lower part hot water temperature detected by the first stored hot water temperature detecting means 18ad is higher than the upper part hot water temperature detected by the second store hot water temperature detecting means 18au, at the time when the boiling-up operation finishes in the night time zone mode 31B.SELECTED DRAWING: Figure 1

Description

The present invention relates to a water heater having a boiling operation mode.

Patent Document 1 proposes preventing a decrease in heating efficiency by controlling the daytime heating operation stop temperature to be lower than the nighttime heating operation stop temperature.

Patent No. 3867547

BACKGROUND ART Recently, a water heater has been proposed that works in conjunction with a solar power generation system to actively use electric power generated in-house during the daytime to boil hot water in a hot water storage tank. In such a water heater, the boiling time during daytime hours is longer than that of a conventional water heater (which mainly boils water at night). In such a water heater that mainly performs daytime boiling, the control method described in Patent Document 1 shortens the daytime boiling time, which obstructs the original purpose of actively utilizing daytime power. Moreover, there is a possibility that the boiling efficiency will be reduced. This is because the boiling time during the daytime hours when heating efficiency is high is shortened, and the heat radiation loss from boiling to when it is used by the user increases.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a water heater that can improve boiling efficiency when boiling operation is performed during daytime hours and nighttime hours.

The hot water supply device of the present invention according to claim 1 includes a hot water storage tank 10, a heating device 20 that heats hot water in the hot water storage tank 10, and a control device 30, and the control device 30 is configured to control the heating device 20. has a boiling operation mode 31 in which the hot water in the hot water storage tank 10 is heated, and the boiling operation mode 31 includes a daytime time zone mode 31A in which the boiling operation is executed during the daytime time zone, and a night time zone mode 31A in which the hot water in the hot water storage tank 10 is heated. A water heater having a night time mode 31B in which the boiling operation is performed during the day, and in which the amount of daytime boiling water heated in the daytime time mode 31A is 50% or more of the total amount of boiling water in one day. The hot water temperature detection means 18a for detecting the temperature of the hot water in the hot water storage tank 10 includes a first hot water temperature detection means 18ad for detecting the temperature of the lower part of the hot water tank 10, and the first hot water temperature detection means 18ad for detecting the temperature of the hot water in the lower part of the hot water storage tank 10. and a second hot water storage temperature detection means 18au for detecting the upper hot water temperature at a position higher than the means 18ad, and the control device 30 has a second hot water storage temperature detection means 18au that detects the upper hot water temperature at a higher position than the means 18ad. In the night time zone mode 31B, the upper hot water temperature is detected by the second hot water storage temperature detection means 18au, and at the end of the boiling operation in the night time zone mode 31B, the second hot water temperature is detected. The boiling operation in the daytime mode 31A is ended in a state where the lower hot water temperature detected by the first hot water storage temperature detecting means 18ad is higher than the upper hot water temperature detected by the detecting means 18au. It is characterized by
According to a second aspect of the present invention, in the hot water supply device according to the first aspect, when the lower water temperature detected by the first hot water storage temperature detection means 18ad reaches the daytime boiling end temperature, the daytime time It is characterized in that the boiling operation in band mode 31A is ended.
The hot water supply device of the present invention according to claim 3 is the hot water supply device according to claim 1 or 2, when the upper water temperature detected by the second hot water storage temperature detection means 18au reaches the nighttime boiling end temperature. , the boiling operation in the nighttime mode 31B is terminated.
The water heater according to the present invention according to claim 4 is the water heater according to any one of claims 1 to 3, when the daytime operation start time and the daytime operation end time when the daytime time zone mode 31A is executed. An operating means 40 is provided that allows the user to set at least either the time or the daytime driving execution time, and the operating means 40 sets the daytime driving time to be less than a preset minimum driving time. It is characterized by the fact that it cannot be done.
The water heater of the present invention according to claim 5 is the water heater according to any one of claims 1 to 4, in which electric power obtained by the solar power generation device 50 is used in the daytime mode. It is characterized by

According to the present invention, the water temperature in the lower part of the hot water storage tank at the end of the boiling operation in the daytime mode is set higher than the water temperature in the upper part of the hot water storage tank at the end of the boiling operation in the nighttime mode. As a result, more hot water can be heated during the daytime when the outside air temperature is high and the time before the main use of hot water is shorter than during the nighttime, and during the daytime when the outside air temperature is higher than during the nighttime. Heating efficiency is high by boiling a large amount of water in the belt, and since the time until evening, which is the main usage time, is short, heat radiation loss is small, so boiling can be done efficiently.

A configuration diagram of a water heater according to an embodiment of the present invention Diagram explaining the operation of the water heater Control flow diagram of the water heater

The hot water supply device according to the first embodiment of the present invention includes, as a hot water temperature detection means for detecting the temperature of hot water in the hot water storage tank, a first hot water temperature detection means for detecting the temperature of hot water in a lower part of the hot water storage tank; and a second hot water storage temperature detection means for detecting the upper water temperature at a position higher than the temperature detection means. In the time zone mode, the upper hot water temperature is detected by the second hot water temperature detection means, and the first hot water temperature is higher than the upper hot water temperature detected by the second hot water temperature detection means at the end of the boiling operation in the night time zone mode. The boiling operation in the daytime mode is terminated when the lower water temperature detected by the detection means is high. According to the present embodiment, the temperature of the lower part of the hot water tank at the end of the boiling operation in the daytime mode is higher than the temperature of the upper part of the hot water tank at the end of the boiling operation in the nighttime mode. By doing so, it is possible to boil more hot water during the daytime when the outside temperature is high and the time until the main use of hot water is short than during the nighttime, and the outside temperature is higher than during the nighttime. Heating efficiency is high by boiling a large amount of water during the daytime hours, and since the time until evening, which is the main time of use, is short, there is less heat loss, and boiling can be done efficiently.

In the second embodiment of the present invention, in the water heater according to the first embodiment, when the lower water temperature detected by the first hot water storage temperature detection means reaches the daytime boiling end temperature, the hot water supply device according to the first embodiment is activated in the daytime mode. This ends the boiling operation. According to the present embodiment, the boiling operation in the daytime mode can be ended with the lower water temperature being higher than the upper water temperature at the end of the nighttime mode.

In the third embodiment of the present invention, in the hot water supply apparatus according to the first or second embodiment, when the upper water temperature detected by the second hot water storage temperature detection means reaches the nighttime boiling end temperature, This ends the boiling operation in mode. According to this embodiment, the temperature of the upper part of the hot water tank at the end of the boiling operation in the nighttime mode can be controlled.

A fourth embodiment of the present invention provides a water heater according to any one of the first to third embodiments at a daytime operation start time, a daytime operation end time, or a daytime operation when the daytime mode is executed. It is provided with an operation means that allows the user to set at least one of the execution times, and the operation means cannot set the set daytime driving time to be less than a preset minimum driving time. According to the present embodiment, by ensuring daytime boiling time that is longer than the minimum operating time, it is possible to achieve an optimal ratio of operation between daytime mode and nighttime mode.

A fifth embodiment of the present invention uses electric power obtained by a solar power generation device in the daytime mode in the water heater according to any one of the first to fourth embodiments. According to the present embodiment, the electric power obtained by the solar power generation device can be effectively used for heating during the daytime hours.

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a configuration diagram of a water heater according to this embodiment.
The hot water supply device according to this embodiment includes a hot water storage tank 10, a heating device 20 that heats hot water in the hot water storage tank 10, a control device 30 that controls the heating device 20, and a user can set the setting conditions of the control device 30. The operating means 40 is also provided.

Hot water in the hot water storage tank 10 is led out from the bottom of the hot water storage tank 10, passed through the boiling pipe 11 to the heating device 20, heated to a high temperature by the heating device 20, and then introduced from the top of the hot water storage tank 10 to be stored. Hot water is stored in a tank 10. When the hot water tap 12 is opened, the heated hot water in the hot water storage tank 10 is mixed to a predetermined temperature with the water supplied from the water supply pipe 14 by the mixing valve 13, and the hot water is supplied from the hot water tap 12.
Hot water that is insufficient in the hot water storage tank 10 due to hot water supply from the hot water tap 12 is supplied from a water supply pipe 14 connected to the bottom of the hot water storage tank 10, and the hot water storage tank 10 is always filled with hot water.
The boiling pipe 11 from the hot water storage tank 10 to the heating device 20 has a circulation pump 16, and when the circulation pump 16 operates, the hot water in the hot water storage tank 10 is passed through the heating device 20, and the hot water from the hot water storage tank 10 is passed through the heating device 20. Hot water is stored at 10.

A hot water supply pipe 15 extending from the hot water storage tank 10 to the hot water tap 12 is equipped with a hot water supply flow rate detection means 17 for detecting the amount of hot water supplied to the hot water tap 12 .
The hot water storage tank 10 is equipped with a hot water temperature detection means 18a, the water supply pipe 14 that supplies water to the lower part of the hot water storage tank 10 is equipped with a water supply temperature detection means 18b, and the boiling pipe 11 from the hot water storage tank 10 to the circulation pump 16 is equipped with a water supply pipe 14 that supplies water to the lower part of the hot water storage tank 10. A temperature detection means 18c is provided.
The hot water temperature detection means 18a detects the temperature of hot water in the hot water storage tank 10, and is higher than at least the first hot water temperature detection means 18ad that detects the lower part of the hot water temperature of the hot water storage tank 10, and the first hot water temperature detection means 18ad. It has a second hot water storage temperature detection means 18au for detecting the upper hot water temperature at the position.
At least one of the first hot water storage temperature detection means 18ad, the supply water temperature detection means 18b, and the supply water temperature detection means 18c can be used to detect the supply water temperature.

A heat pump device including a compressor, a radiator, a pressure reducer, and an evaporator is suitable for the heating device 20. When a heat pump device is used as the heating device 20, heat radiation from a radiator is used as a heating source. By using the heating device 20 as a heat pump device, electric power can be used effectively.
Further, it is preferable that the water heater according to this embodiment receives power from the solar power generation device 50, and the power obtained by the solar power generation device 50 can be used in the daytime mode 31A. By linking with the solar power generation device 50, the electric power obtained by the solar power generation device 50 can be effectively used for heating during the daytime.

The control device 30 has a boiling operation mode 31. In the boiling operation mode 31, the heating device 20 heats the hot water in the hot water storage tank 10. The boiling operation mode 31 includes a daytime mode 31A in which the boiling operation is carried out during the daytime, and a nighttime mode 31B in which the boiling operation is carried out in the nighttime.
The control device 30 has timer means 32 . The timer means 32 measures time and can determine the year, month, day, and time. Therefore, the timer means 32 determines whether it is a daytime period or a nighttime period. The daytime time zone and the nighttime time zone may be set in advance or may be changed by operating the operating means 40. For example, the daytime period is set from 9:00 to 16:00, and the night time period is set from 11:00 p.m. to 6:00 p.m.

The control device 30 includes a used hot water amount storage means 33A, a supply water temperature storage means 33B, and a set condition storage means 33C.
The used hot water amount storage means 33A stores the amount of hot water detected by the hot water supply flow rate detection means 17 together with the time measured by the timer means 32. The used hot water amount storage means 33A stores the hot water amount for each time period, such as one day, one week, one month, and one year, as a hot water amount history.
The feed water temperature storage means 33B stores the feed water temperature detected by the feed water temperature detection means 18b or the feed water temperature detection means 18c together with the time measured by the timer means 32. The water supply temperature storage means 33B stores the water supply temperature for each time zone during a predetermined period such as one day, one week, one month, and one year.
The control device 30 operates the circulation pump 16 during the night time period when the amount of heat of the hot water in the hot water storage tank 10 is estimated to be at its minimum, and operates the circulation pump 16 to detect the temperature of the water supply in the water supply temperature detection means 18c. Do it later. In this way, by operating the circulation pump 16, the water supply temperature can be detected without being affected by the hot water in the hot water storage tank 10 or the outside temperature, and it is estimated that the amount of heat of the hot water in the hot water storage tank 10 is minimized. By operating the circulation pump 16 during the nighttime hours when the circulation pump 16 is operating, the temperature of the supplied water can be detected without being affected by the hot water in the hot water storage tank 10 or the outside air temperature even if the operation time of the circulation pump 16 is shortened. When hot water is being supplied from the hot water tap 12, the supplied water temperature can be detected by the supplied water temperature detection means 18b without being affected by the hot water in the hot water storage tank 10 or the outside temperature.

The setting condition storage means 33C stores at least one setting condition among the daytime driving start time, the daytime driving end time, or the daytime driving execution time under which the daytime mode 31A is executed. These setting conditions are set by the operating means 40.
The operating means 40 limits the setting conditions so that the daytime setting driving time cannot be set to be less than a preset minimum driving time. For example, if the minimum driving time is set to 4 hours in advance in the control device 30, the user can set the daytime driving execution time to 4 hours or more, but the user can set the daytime driving time to less than 4 hours. I don't accept what you do. The same applies to the daytime driving start time and the daytime driving end time, and if the daytime driving start time is 9 o'clock, the daytime driving end time is set to 12:00, when the daytime driving execution time is less than 4 hours. I don't accept that. If the user sets the daytime driving start time as 9 o'clock, the user can set a time after 13:00 as the daytime driving end time.

The minimum operating time is such that the lower water temperature detected by the first hot water storage temperature detection means 18ad is higher than the upper water temperature detected by the second hot water storage temperature detection means 18au at the end of the boiling operation in the nighttime mode 31B. The boiling operation in daytime mode 31A is set to end when the temperature is high.
Further, the minimum operating time is such that the amount of daytime boiling water heated in the daytime mode 31A is 50% or more of the total amount of boiling water in one day. By setting the amount of hot water to be heated during the day to 50% or more of the total amount of hot water for one day, heating can be reliably performed during the day. Compared to nighttime, during the day, the outside air temperature is higher and less heat is radiated, so heat retention is better, and because the time until evening, which is the main usage time, is shorter, there is less heat loss, making boiling more efficient. be able to. Furthermore, when a heat pump device is used as the heating device 20, the outside air temperature is higher during the day than at night, so that heating can be performed efficiently.

The control device 30 includes a total boiling water amount calculating means 34A that calculates the total amount of boiling water for one day, and a set boiling water amount calculating means that calculates the set boiling water amount at the daytime setting operating time set by the operating means 40. 34C, and boiling water amount comparison means 34D that compares the set amount of boiling water with the total amount of boiling water for one day.
The total amount of boiling hot water calculation means 34A calculates the total amount of hot water for one day based on the history of the amount of hot water used stored in the amount of hot water used storage means 33A.

The set boiling water amount calculation means 34C calculates the set boiling water amount based on the daytime setting operating time stored in the setting condition storage means 33C. Note that it is preferable to determine the set amount of boiling water using the water supply temperature stored in the water supply temperature storage means 33B. This is because even if the length of the set daytime operation time is the same, the set amount of boiling water varies depending on the water supply temperature. As the water supply temperature here, the water supply temperature at the time of detection can be used, but the lowest temperature, highest temperature, or average temperature of the past seven days may also be used, for example. By using the lowest temperature in the past predetermined period, it is possible to prevent hot water from running out. Outside air temperature can also be used in conjunction with feed water temperature.
Furthermore, the water supply temperature can be divided into summer water supply temperature, winter water supply temperature, and intermediate season water supply temperature.

The boiling water amount comparison means 34D compares the total daily boiling water amount calculated by the total boiling water amount calculation means 34A and the set boiling water amount calculated by the set boiling water amount calculation means 34C.
In the boiling water amount comparing means 34D, if the set boiling water amount is equal to or greater than the total boiling water amount for one day, the daytime operation end time determining means 35B determines the daytime operation end time in the daytime time zone mode 31A.

In the daytime operation end time determining means 35B, the lower water temperature of the hot water storage tank 10 detected by the first hot water temperature detection means 18ad is determined by the second hot water temperature detection means 18au at the end of the boiling operation in the nighttime mode 31B. When the daytime boiling end temperature is higher than the upper water temperature of the hot water storage tank 10 detected at , the boiling operation in the daytime mode 31A is ended. Here, the temperature at the upper part of the hot water storage tank 10 at the end of the boiling operation in the nighttime mode 31B can be the temperature at the end of the immediately preceding nighttime mode 31B, but for example, the lowest temperature in the past seven days can be used. The temperature, maximum temperature, or average temperature may be used as the daytime boiling end temperature. In addition, the upper water temperature of the hot water storage tank 10 at the end of the boiling operation in the nighttime mode 31B is divided into upper water temperature for summer, upper water temperature for winter, and upper water temperature for intermediate period, and the upper water temperature for daytime boiling is The end temperature for raising the temperature may be changed.

In the boiling water amount comparing means 34D, if the set boiling water amount is less than the total boiling water amount, the night operation time calculating means 36A calculates the night operation time in the night time zone mode 31B so that the total boiling water amount is satisfied. .
If the set boiling water amount is less than the total boiling water amount, the lack of boiling water can be eliminated by lengthening the nighttime operation time in the night time zone mode 31B.
The control device 30 starts driving so that the night driving time calculated by the night driving time calculation means 36A is performed, and the night driving end time determining means 36B determines the night driving end time in the night time zone mode 31B. . The nighttime operation end time determining means 36B ends the boiling operation in the nighttime mode 31B when the upper water temperature of the hot water storage tank 10 detected by the second hot water storage temperature detection means 18au reaches the nighttime boiling end temperature. . The nighttime boiling end temperature is set to a lower temperature than the daytime boiling end temperature. In addition, in the nighttime operation end time determination means 36B, the upper water temperature of the hot water storage tank 10 detected by the second hot water storage temperature detection means 18au at the end of the boiling operation in the night time zone mode 31B becomes the nighttime boiling end temperature. Night driving hours may be set as follows.

In this manner, the control device 30 detects the lower hot water temperature of the hot water storage tank 10 by the first hot water temperature detection means 18ad in the daytime mode 31A, and detects the upper hot water temperature by the second hot water temperature detection means 18au in the nighttime mode 31B. Detects temperature. At the end of the boiling operation in the nighttime mode 31B, the lower part of the hot water storage tank 10 detected by the first hot water temperature detection means 18ad is lower than the upper part of the hot water storage tank 10 detected by the second hot water temperature detection means 18au. By ending the boiling operation in daytime mode 31A when the water temperature is high, the amount of hot water can be increased during the daytime when the outside temperature is high and the time until the main use time of hot water is short compared to during the nighttime. You can boil water. Heating efficiency is high by boiling more hot water during the daytime when the outside air temperature is higher than at nighttime, and there is less heat loss due to the short time until evening, which is the main usage time, making it more efficient. Can be heated.

In this embodiment, by determining the end of the boiling operation in the daytime mode 31A based on the lower water temperature detected by the first hot water storage temperature detection means 18ad, the end of the boiling operation in the nighttime mode 31B is determined. The boiling operation in the daytime mode 31A can be ended with the lower water temperature being higher than the upper water temperature at the time of termination.
In addition, by determining the end of the boiling operation in the nighttime mode 31B based on the upper water temperature detected by the second hot water storage temperature detection means 18au, the end of the boiling operation in the nighttime mode 31B can be determined. The upper water temperature can be controlled.

FIG. 2 is an explanatory diagram of the operation of the water heater according to this embodiment.
In this embodiment, the control device 30 sets the daytime period from 9:00 to 16:00, the nighttime period from 11:00 p.m. to 6:00 p.m., and sets the minimum driving time in the daytime period to 4 hours.

FIG. 2(a) shows an example of the use of hot water supply. For example, as shown in FIG. 2(a), hot water is used from 18:00 to 22:00, at 7:00, and at 12:00.
FIG. 2(b) shows the state of hot water in the hot water storage tank 10.
FIGS. 2(c) and 2(d) show operating hours of the heating device 20.

At 23:00, which is the start time of the nighttime period, the control device 30 calculates the total amount of boiled water for the day using the total amount of boiled water calculation means 34A.
Operating state A shown in FIG. 2(c) indicates a case where the set amount of boiling hot water during the daytime setting operating time is equal to or greater than the total amount of boiling hot water for the day.
Driving state A is a case where the user has set the daytime driving time from 9:00 to 16:00.
The control device 30 starts operation at 9 o'clock, which is the daytime operation start time, if the set amount of boiling hot water in the set daytime operation time is greater than or equal to the total amount of boiling water for the day, and the daytime operation end time is determined by the daytime operation end time determining means 35B. The daytime time zone mode 31A ends at the daytime driving end time.

Operating state B shown in FIG. 2(d) indicates a case where the set amount of boiling hot water during the daytime setting operating time is less than the total amount of boiling hot water for the day.
Driving state B is a case where the user has set the daytime driving time from 12:00 to 16:00.
If the set amount of boiling hot water in the daytime setting operating time is less than the total amount of boiling hot water for one day, the control device 30 calculates the nighttime operating time in the night time zone mode 31B so as to equal the total amount of boiling hot water.
In the nighttime mode 31B, the boiling operation is completed during the calculated nighttime operation time or when the upper water temperature of the hot water storage tank 10 detected by the second hot water storage temperature detection means 18au reaches the nighttime boiling end temperature. do.

FIG. 3 is a control flow diagram of the water heater according to this embodiment.
The control device 30 calculates the total amount of boiling hot water for one day using the hot water usage history data (S1), and calculates the set amount of boiling hot water for the set operating time based on the set operating time in the daytime mode 31A ( S2).
Then, the control device 30 compares the set amount of boiling water calculated in S2 with the total amount of boiling water for the day calculated in S1 (S3).
If the calculated set amount of boiling water is equal to or greater than the total amount of boiling water for the day (Yes in S3), operation is started from the daytime operation start time set by the operating means 40 (S4), and the first hot water storage temperature is detected. If the lower water temperature of the hot water storage tank 10 detected by the means 18ad is lower than the daytime boiling end temperature (No in S5), daytime operation is continued, and the temperature of the hot water storage tank 10 detected by the first hot water storage temperature detection means 18ad is When the lower water temperature reaches the daytime boiling end temperature (Yes in S5), the daytime operation in the daytime mode 31A is ended (S6).
If the calculated set amount of boiling water is less than the total amount of boiling water for the day (No in S3), the nighttime operation time in the night time zone mode 31B is calculated so as to reach the total amount of boiling water (S7).

When the daytime driving start time set by the operating means 40 comes, daytime driving is performed in the daytime time zone mode 31A until the set daytime driving end time (S8).
In addition, when the night time period comes, night driving is started so that the night driving time calculated by the night driving time calculating means 36A can be started (S9), and the temperature of the hot water storage tank 10 detected by the second hot water storage temperature detecting means 18au is increased. If the upper water temperature is less than the nighttime boiling end temperature (No in S10), the nighttime operation is continued, and the upper water temperature of the hot water storage tank 10 detected by the second hot water storage temperature detection means 18au becomes the nighttime boiling end temperature. If this is the case (Yes in S10), the night driving in the night time zone mode 31B is ended (S11).

In addition, in order to make the amount of daytime boiling water heated in the daytime mode 31A equal to or higher than a predetermined ratio with respect to the total amount of boiling water for the day determined in S1, the operating means 40 controls the daytime setting operating time. It is preferable to restrict the setting so that the operation time is less than a preset minimum operation time, and by ensuring the daytime boiling time is longer than the minimum operation time, the difference between the daytime mode 31A and the nighttime mode 31B can be reduced. You can adjust your driving to the optimal ratio.

According to the present invention, efficient daytime mode operation can be effectively performed.

10 hot water storage tank 11 boiling pipe 12 hot water tap 13 mixing valve 14 water supply pipe 15 hot water pipe 16 circulation pump 17 hot water flow rate detection means 18a hot water temperature detection means 18ad first hot water temperature detection means 18au second hot water temperature detection means 18b, 18c water supply Temperature detection means 20 Heating device 30 Control device 31 Boiling operation mode 31A Daytime mode 31B Nighttime mode 32 Timer means 33A Used hot water amount storage means 33B Water supply temperature storage means 33C Setting condition storage means 34A Total boiling water amount calculation means 34C Set boiling water amount calculation means 34D Boiling water amount comparison means 35B Daytime operation end time determination means 36A Nighttime operation time calculation means 36B Nighttime operation end time determination means 40 Operation means 50 Solar power generation device

Claims (5)

comprising a hot water storage tank, a heating device that heats hot water in the hot water storage tank, and a control device,
The control device has a boiling operation mode in which the heating device heats the hot water in the hot water storage tank,
The boiling operation mode is
A daytime mode that performs boiling operation during the daytime,
and a nighttime mode in which the boiling operation is performed during the nighttime,
A hot water supply device in which the amount of daytime boiling water heated in the daytime mode is 50% or more of the total amount of boiling water in one day,
As a hot water storage temperature detection means for detecting the temperature of the hot water in the hot water storage tank,
a first hot water storage temperature detection means for detecting the temperature of hot water in the lower part of the hot water storage tank;
a second hot water storage temperature detection means for detecting an upper hot water temperature at a position higher than the first hot water storage temperature detection means;
The control device includes:
In the daytime mode, the first hot water storage temperature detection means detects the lower hot water temperature;
In the nighttime mode, the second hot water storage temperature detection means detects the upper hot water temperature;
A state in which the lower hot water temperature detected by the first hot water storage temperature detection means is higher than the upper hot water temperature detected by the second hot water storage temperature detection means at the end of the boiling operation in the nighttime mode. The hot water supply device is characterized in that the boiling operation in the daytime mode is ended. The hot water supply according to claim 1, wherein the boiling operation in the daytime mode is ended when the lower water temperature detected by the first hot water storage temperature detection means reaches a daytime boiling end temperature. Device. Claim 1 or 2, wherein the boiling operation in the nighttime mode is ended when the upper water temperature detected by the second hot water storage temperature detection means reaches a nighttime boiling end temperature. The water heater described in . comprising an operating means that allows the user to set at least one of a daytime driving start time, a daytime driving end time, or a daytime driving execution time in which the daytime mode is executed;
The hot water supply apparatus according to any one of claims 1 to 3, wherein the operation means cannot set the daytime setting operating time to be less than a preset minimum operating time. The water heater according to any one of claims 1 to 4, characterized in that the daytime mode uses electric power obtained by a solar power generation device.