JP2009127992A - Hot water supply apparatus, and operation method of hot water supply apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hot water supply apparatus capable of fully exhibiting the original capacity of a heat pump type hot water supply part even in a cold district. <P>SOLUTION: A conventional hot water supply apparatus for heating water by a heat pump type water heater and storing the hot water in a hot water storage tank in a night time zone with a low electric charge cannot fully exhibit the original capacity of the heat pump type water heater at night in the cold district where an outside air temperature extremely drops. The heat pump type water supply part is thereby operated in the daytime, and hot water in the hot water storage tank is heated by a heater at night. The heat pump type hot water supply part can thereby be used with high energy consumption efficiency while eliminating the shortage of hot water caused by the shortage of a heating value at night. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hot water supply apparatus including a heat pump type hot water supply section and a heater type hot water storage tank.

In recent years, for the purpose of hot water supply and air conditioning, water heaters and air conditioning equipment using the principle of a heat pump have been widely used. The heat pump type hot water heater can circulate a refrigerant such as chlorofluorocarbon while expanding and compressing it, and specifically has the following mechanism.
First, the refrigerant is expanded, exposed to the outside air in a state where the temperature of the refrigerant is low, and the temperature of the refrigerant is raised by the heat of the outside air. Next, the refrigerant is compressed to raise the temperature, and the tap water is heated by the heat of the refrigerant that has become high. Then, the circulation in which the refrigerant that has released the heat is expanded again and exposed to the outside air is repeated. That is, the basic principle of the heat pump water heater is that heat energy is pumped from the outside air by repeating expansion / compression operations on the refrigerant, and the tap water is heated by the pumped heat.

In the conventional hot water supply apparatus provided with this heat pump type hot water heater and a hot water storage tank, the structure which heats the water stored in a hot water storage tank with the heat pump type hot water heater has been adopted. With this configuration, there is a method in which hot water is boiled with a heat pump water heater at night when electricity charges are set at a low price and stored in a hot water tank, and the hot water stored in the hot water tank fills the daily demand for hot water. Have been used (see, for example, Patent Document 1).
In addition, when the heat pump water heater alone cannot boil all the hot water required at night, a method using a heater provided in a hot water tank or a method using a heat pump water heater to boil the shortage in the daytime is used. (For example, refer to Patent Document 2).

Japanese Examined Patent Publication No. 4-6851 JP-A-7-98156

  In the conventional method, the heat pump water heater is operated and heated at night, so the energy consumption efficiency of the heat pump water heater is significantly reduced, especially in cold regions in winter, and the heat pump water heater that pumps up heat energy from the outside air There was a problem that I could not make full use of my ability.

  Moreover, since all the hot water discharged is hot water once stored in the hot water storage tank, it is necessary to prepare a hot water storage tank having a size corresponding to the daily demand for hot water. In a normal home, it is about 300 to 500 liters. For this reason, there has been a problem that the hot water tank is enlarged.

  The present invention has been made in view of such circumstances, and uses a heat pump type water heater in a state where it is easy to demonstrate its capabilities, and has a small hot water tank that can be operated at a low electric charge. The purpose is to provide.

  The hot water supply apparatus and the operation method of the hot water supply apparatus according to the present invention include a hot water storage tank provided with a heater and a heat pump hot water supply unit that can be operated in parallel, and a predetermined time zone at night is more expensive than other time zones. A hot water supply apparatus that uses commercial power set as a low-priced low-cost time zone as a power source, and includes a control unit that controls the operation of the hot water storage tank and the heat pump type hot-water supply unit. The control unit controls the hot water in the hot water storage tank to be preferentially discharged over the hot water from the heat pump hot water supply part, while heating the hot water in the hot water storage tank with the heater, except for the low-cost time zone. In the first normal time period, the control unit stops the heating operation by the heater and prioritizes the hot water from the heat pump hot water supply unit over the hot water in the hot water tank. In the second normal time zone other than the first normal time zone in the normal time zone, the control unit stops the heating operation by the heater and the hot water storage tank The hot water is controlled to be discharged preferentially over hot water from the heat pump hot water supply section (claims 1 and 5).

  According to the present invention, since the heat pump hot water supply unit is operated during the daytime when the heat energy can be efficiently pumped from the outside air, the heat energy acquisition capability inherent to the heat pump hot water supply unit can be sufficiently exhibited. In addition, since the hot water storage tank only needs to store hot water used during a part of the daytime period and at night, the hot water storage tank can be downsized (for example, about 200 liters). In addition, since the heater, which has relatively low energy consumption efficiency compared to the heat pump hot water supply unit, is operated only in the time zone where the electricity rate is low, it can be operated at a low electricity rate.

  The second normal time zone is separated into a third normal time zone before the first normal time zone and a fourth normal time zone after the first normal time zone. The first normal time zone is preferably configured such that its end time varies according to the amount of hot water remaining in the hot water storage tank at the end of the third normal time zone (Claim 2).

  In the second normal time zone, the hot water stored in the hot water tank is used at night, so if the demand for hot water in the second normal time zone is unexpected, there may be a shortage of hot water or a significant excess There is. Therefore, the second normal time zone is divided into two time zones (third and fourth normal time zones) before and after the first normal time zone, and the third normal time in the first half. By adjusting the length of the fourth normal time zone in the second half according to the remaining hot water amount at the end of the belt (or the amount of hot water used in the third normal time zone), the heat pump hot water supply section and hot water storage tank Both can be used effectively without waste.

That is, when the amount of remaining hot water at the end of the third normal time period is less than expected (when the amount of hot water used in the third normal time period is greater than expected), the length of the first normal time period is set to While it is longer than usual to save hot water in the hot water tank and use the heat pump hot water supply unit as much as possible, if the remaining hot water amount is higher than expected (the amount of hot water used in the third normal time zone is assumed) In the case of less than that), the length of the first normal time zone was made shorter than usual, and hot water in the hot water tank was used as much as possible.
It should be noted that the length of the first normal time zone is varied both when the amount of remaining hot water is small and when it is large, but is varied only in either case (for example, only when the amount of remaining hot water is small). May be.
Further, the range in which the length of the first normal time zone is changed may be determined in advance, for example, to plus or minus 1 hour, and may be changed only within the range.

The first normal time zone may be a time zone that satisfies at least one of the following (1) and (2) (claim 3).
(1) A time zone in which the outside air temperature is higher than the predetermined first temperature.
(2) A time zone in which a coefficient of performance COP (Coefficient of Performance) in the heat pump hot water supply section is equal to or greater than a predetermined time, starting from one time before noon and until another time past noon.
During the time period satisfying at least one of the above (1) and (2), the energy consumption efficiency by the heat pump hot water supply unit is high, so that heat energy can be efficiently taken in from the outside and utilized.
By selecting this time zone and operating the heat pump hot water supply unit, the energy consumption efficiency of the hot water supply device can be reliably increased.

The coefficient of performance COP refers to the ratio of the amount of heat energy given to water by the heat pumped from outside air to the total amount of electric energy given to the compressor that causes the heat pump hot water supply section to expand and compress. It can be said that the larger the value, the higher the efficiency.
Since the electricity rate in the low-cost time zone is often set to about one third of the normal time zone, it is preferable to use the heat pump hot water supply section in a state where the COP is approximately 3.0 or more.

Further, in the inexpensive time zone, the control unit can increase or decrease the discharge amount of hot water from the heat pump hot water supply unit according to the outside air temperature (Claim 4).
In low-priced time zones, hot water from the hot water tank is usually preferentially used. However, when the outdoor air temperature is high even at night, such as in summer, the heat pump hot water supply unit can fully demonstrate its capabilities. Therefore, the heat pump hot water supply section can be utilized even in the low-cost time zone. In other words, the flexibility of the system can be increased by increasing or decreasing the amount of hot water supplied from the heat pump hot water supply section that is used non-priorarily according to the outside air temperature, and further efficiency and cost reduction can be achieved. .

  As described above, in the hot water supply apparatus of the present invention, the hot water storage tank and the heat pump type hot water supply unit can be operated in parallel, and the heat pump type hot water supply unit is aimed and operated in a time zone where the energy consumption efficiency is high. Therefore, it has a small hot water storage tank and can be operated at a low electricity charge.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram showing an outline of equipment arrangement of a hot water supply apparatus according to the present invention, and includes a hot water tank 1, a heat pump hot water supply unit 2, and a control unit 3.

[Overall system configuration]
A water intake pipe 6 connected to a water supply pipe such as tap water has a structure in which the water is branched into two and flows into the hot water tank 1 and the heat pump hot water supply section 2 respectively.
The hot water tank 1 is equipped with a plurality of water temperature gauges, measuring devices for measuring the amount of remaining hot water, and the like, and constantly monitors the temperature of the hot water in the hot water tank 1 and the amount of remaining hot water.
The clean water flowing into the hot water storage tank 1 and stored therein is heated by the heater 4 and held.
Moreover, the clean water which flowed into the heat pump hot water supply unit 2 is heated and flows out by the principle of the heat pump.
Hot water flowing out from the hot water storage tank 1 and the heat pump hot water supply unit 2 is discharged to the hot water discharge pipe 7 through the hot water discharge valve 5 and sent to a washroom or a bathroom.

The control unit 3 has a function of controlling the hot water tank 1 and the heater 4, acquires the temperature of hot water and the amount of remaining hot water in the hot water tank 1, and starts / stops the operation of the heater 4 according to the temperature of the hot water. It has a function.
In addition, the heat pump hot water supply unit 2 has a function of instructing to start and stop the heating operation.
And it also has the function to control the discharge | emission amount of the hot water from the hot water storage tank 1 and the hot water from the heat pump hot water supply part 2 by controlling the hot water discharge valve 5. FIG.

[Basic operation of hot water tank 1 and heater 4]
First, the basic operation of the hot water tank 1 will be described.

The hot water storage tank 1 is provided with a water intake valve (not shown) that opens and closes an inlet of clean water from the water intake pipe 6. When the water intake valve is opened in accordance with an instruction from the control unit 3, It has become a mechanism to flow in.
When the inflow of clean water is started, the remaining hot water measuring device (not shown) separately provided in the hot water tank 1 is used to monitor the remaining hot water amount (remaining water amount) in the hot water tank 1 so that the hot water tank 1 becomes full. At that point, close the intake valve.

The temperature of the hot water in the hot water tank 1 can be measured by a plurality of water thermometers (not shown) provided in the hot water tank 1. A plurality of water thermometers are provided at different heights from the bottom surface of the hot water tank 1, and have a mechanism capable of measuring in real time how much hot water has been heated.
The heater 4 has a function of starting / stopping the heating operation of the hot water in the hot water tank 1 in accordance with an instruction from the control unit 3.

[Basic operation of heat pump hot water supply unit 2]
The basic operation of the heat pump hot water supply unit 2 will be described.

The heat pump hot water supply unit 2 has a mechanism for pumping heat from the outside air by circulating the refrigerant while compressing and expanding it, and heats the water with the heat absorbed from the outside air.
The clean water flowing in from the intake pipe 6 passes through a meandering pipe inside the heat pump hot water supply unit 2, and a heat source (not shown) is arranged at a position close to the meandering pipe. The heat given to the heat source is taken out when the refrigerant circulating in the heat pump is compressed to a high temperature state.

The clean water is heated while passing through the meandering pipe, and is raised to a high temperature when discharged from the heat pump hot water supply unit 2.
The heat pump hot water supply unit 2 can control the flow rate of clean water passing through the meandering pipe according to the amount of heat pumped by the heat pump (according to the temperature of the compressed refrigerant). When the amount of heat generated is small, the flow rate is reduced, and when the amount of heat pumped up is large, the flow rate is increased so that the temperature of the hot water discharged from the heat pump hot water supply section 2 can be kept within a substantially constant range. It has become.

  The heat pump hot water supply unit 2 starts and stops the heating operation in accordance with a signal from the control unit 3 as in the hot water tank 1 and the like.

[Basic operation of control unit 3]
Next, the basic operation of the control unit 3 will be described in detail.

The control unit 3 is a computer device including a CPU, and includes a storage unit such as a ROM and a memory, a time measuring unit for realizing a clock function, and the like, and the operation can be switched according to a time zone or the like. It has a mechanism.
In addition, signals are exchanged among the hot water tank 1, the heat pump hot water supply unit 2, the heater 4 and the hot water discharge valve 5, information can be acquired from them, and instructions regarding the operation can be given. Further, a thermometer 8 (not shown) for measuring the outside air temperature is connected to the control unit 3 so that the outside air temperature can be periodically acquired.
First, the operation in the low-cost time zone in which the electricity bill is set at a low price will be described.

The storage unit of the control unit 3 stores in advance information related to the start time and end time (for example, from 23:00 to 7:00 the next morning) in the low-priced nighttime period when the electricity bill is low. It is possible to determine whether or not the current time is at night based on the time information acquired from.
When it is determined that the low-priced time zone has started, the control unit 3 starts the heating operation of the hot water in the hot water tank 1.

First, the control unit 3 instructs the hot water tank 1 to open the intake valve. When the intake valve is opened and water starts to flow in, the remaining hot water amount information obtained by the remaining hot water measuring device in the hot water tank 1 is monitored, and an instruction is given to close the intake valve when the water is full. When the water is full, the heater 4 is instructed to start the heating operation.
When the heating operation by the heater 4 is started, based on the water temperature information obtained from a plurality of water thermometers installed in the hot water storage tank 1, it is monitored how much the temperature of the hot water in the hot water storage tank 1 has increased. The heating operation by the heater 4 is stopped when it is determined that the entire hot water in the tank 1 has reached a predetermined temperature (for example, 95 degrees).
Since the hot water in the hot water storage tank 1 is used in the low-priced time zone, the hot water in the hot water storage tank 1 is discharged at any time during use. Therefore, every time hot water is discharged, the intake valve is opened to replenish the discharged amount of clean water, and the operation of reheating with the heater 4 is repeated.
Then, when the low-priced time period ends, the control unit 3 stops the heating operation by the heater 4.

  When hot water demand occurs during low-cost hours, the hot water in the hot water tank 1 is usually preferentially used. However, if the outside air temperature is higher than a predetermined value (for example, approximately 20 degrees or higher), the hot water in the hot water tank 1 is added. Thus, the heat pump hot water supply unit 2 may be controlled to be used. This is because the heat pump hot water supply section 2 can be utilized with high energy consumption efficiency in the summer season when the outside air temperature is sufficiently high even in the low-cost time zone, and the electricity bill can be saved.

  Here, the control unit 3 sequentially controls the hot water tank 1 and the heater 4, but a microcomputer or the like is separately mounted on the hot water tank 1 side, and the microcomputer opens and closes the intake valve and the heater. The overheating operation 4 may be started / stopped. In that case, the control unit 3 transmits a signal instructing the microcomputer to start the heating operation by the heater 4 at the time when the cheap time zone starts, and when the cheap time zone ends, the heater 3 It is only necessary to transmit a signal instructing to stop the heating operation by 4.

Next, the operation in a normal time zone other than the low-cost time zone will be described with reference to FIG.
FIG. 2 is a diagram illustrating a time zone in which the heater 4, hot water in the hot water tank 1, and the heat pump hot water supply unit 2 are used.
Here, the normal time zone (for example, from 7:00 am to 23:00 pm) is the first normal time zone during the day (for example, from 10 am to 18:00 pm) and the other second normal time zone. The second normal time zone is further divided into a third normal time zone in the first half (for example, from 7:00 am to 10:00 am) and a fourth normal time zone in the second half (for example, from 18:00 am to afternoon Until 23:00).

As shown in FIG. 2, the heater 4 is used only in the low-cost time zone, and the hot water in the hot water tank 1 is not heated in a time zone other than the low-cost time zone.
The hot water in the hot water tank 1 is used in the second normal time zone (third and fourth normal time zones) in addition to the inexpensive time zone, and basically used in the first normal time zone. There is nothing. On the other hand, the heat pump hot water supply unit 2 is mainly used in a first normal time zone with high energy consumption efficiency, and most of the demand for hot water in this time zone is covered by the heat pump hot water supply unit 2.

When the third normal time period starts after 7:00 am, the control unit 3 immediately stops any overheating operation by the heater 4, closes the intake valve and allows the inflow of clean water into the hot water tank 1. Ban. When the demand for hot water is generated, the hot water valve 5 is controlled so that the hot water from the hot water storage tank 1 is discharged preferentially to the hot water pipe 7.
Note that “preferential” here means that, in principle, the hot water in the hot water tank 1 is used during the third normal time period, and only the hot water in the hot water tank 1 is discharged unconditionally. It does not mean that control is performed. For example, if it is equipped with a mechanism that knows the source of hot water, the heat pump hot water supply unit 2 is operated only when it is clear that the source of use is a small amount of use like a washroom, You may control so that hot water may be discharged | emitted from the heat pump type hot-water supply part 2. FIG. Moreover, the method of controlling so that the hot water of the hot water storage tank 1 and the hot water from the heat pump hot water supply unit 2 are always discharged at a ratio of 9 to 1 may be used. That is, it is sufficient if the hot water discharge from the hot water tank 1 is dominant.

After that, when the first normal time period starts after 10 am, the heating operation by the heat pump hot water supply unit 2 is started at the time when demand for hot water occurs, and the hot water from the heat pump hot water supply unit 2 is discharged. The hot water discharge valve 5 is controlled so as to be discharged preferentially to the hot water discharge pipe 7.
Then, when the fourth normal time period starts after 18:00 pm, the hot water from the hot water storage tank 1 is preferentially discharged to the hot water discharge pipe 7 again.

  In this way, the daytime is divided into three time zones (first, third, and fourth normal time zones) in advance, and the respective start times and end times are stored in the storage unit of the control unit 3, Based on the current time acquired by the time measuring unit, it is determined to which time zone the current time belongs, and control is performed to execute the operation in the time zone.

The third normal time zone is an early morning time zone, and since the temperature has not yet risen sufficiently, it cannot be said that the energy consumption efficiency of the heat pump hot water supply unit 2 is sufficiently high. Therefore, it is better to cover the demand for hot water in the third normal time zone with the hot water stored in the hot water tank 1 during the inexpensive time zone.
On the other hand, the first normal time zone is in a state where the temperature is the highest in the day, so the energy consumption efficiency of the heat pump hot water supply unit 2 is high, and the capacity can be fully exhibited. Therefore, in this time zone, it is better to cover the demand for hot water by the heat pump hot water supply unit 2.
And since the fourth normal time zone is a time zone in which the temperature falls as the sun goes down, the hot water stored in the hot water tank 1 is used to cover the demand for hot water as in the third normal time zone. To do.

  In the case of boiling water with a heat pump type water heater at night like a conventional water heater, especially in cold regions, the temperature at night in winter is greatly below 0 degrees, so the amount of heat pumped from the outside air by the heat pump type water heater There is almost nothing, and the hot water in the hot water tank 1 cannot be heated sufficiently at night. This makes it possible to achieve almost the original purpose of the system for increasing the energy consumption efficiency using the heat pump type hot water heater.

The inventor of the present application pays attention to the problem that occurs conspicuously in such a cold region, and aims to operate the heat pump hot water supply unit 2 mainly during the daytime when the ability can be fully utilized. Since the hot water supply device is heated by using the heater 4 in the time zone where the electricity price is low, the heat pump type in a state where the hot water in the hot water tank 1 is insufficiently heated and the energy consumption efficiency is remarkably lowered as in the conventional system. The use of the hot water supply unit 2 can be avoided, and the efficiency of the entire hot water supply apparatus can be increased.
Moreover, since the demand for hot water generated in the daytime is mainly covered by the heat pump hot water supply section 2, it is no longer necessary to store hot water for a whole day in the hot water tank 1, and the hot water tank 1 can be downsized. Became possible.

(Second Embodiment)
The control unit 3 may be operated as follows.

  In the first embodiment, the start time and the end time of the first, third, and fourth normal time zones are stored in advance in the storage unit of the control unit 3, and the operation is switched according to the time. However, these start times and the like may be changed at any time.

For example, when the cheap time period ends, the control unit 3 monitors the outside air temperature acquired from the thermometer 8 as needed, and when the outside air temperature exceeds a predetermined temperature (for example, 20 degrees), the third normal The time zone can be ended regardless of the time.
In the first place, it is based on whether the energy consumption efficiency of the heat pump hot water supply unit 2 is high or not because the system operation is switched by dividing the normal time zone other than the low-price time zone into a plurality of times. If it can be acquired, it is more reliable to determine whether to use the heat pump hot water supply unit 2 according to the outside air temperature.
Similarly, in the fourth normal time zone, when the first normal time zone is started, the outside air temperature acquired from the thermometer 8 is monitored as needed, and is terminated when the outside air temperature falls below a predetermined temperature. be able to.

In addition, when the operation is switched based only on the outside air temperature, the time zone in which the heat pump hot water supply unit 2 can be used becomes extremely short (or cannot be used at all) on the day when the temperature hardly rises during the day. There is a possibility that the hot water in the hot water tank 1 is insufficient.
Therefore, the operation may be switched based on both the time and the outside air temperature.
For example, when the range of the end time of the third normal time zone is determined from 9:30 am to 11:30 am, etc., and after 9:30 am after the start of the third normal time zone The monitoring of the outside air temperature is started, and the third normal time period is ended when the outside air temperature becomes equal to or higher than a predetermined temperature. If the outside air temperature is still lower than the predetermined temperature even at 11:30 am, the third normal time period is terminated at that time.
In this way, the outside air temperature may be monitored only within a predetermined time range, and the end time of the third normal time zone may be varied only within that range. By doing in this way, even if the daytime temperature is lower than normal, the first normal time zone can be secured, so that the hot water in the hot water tank 1 is insufficient. Can be avoided in advance.

Note that the control unit 3 may vary the end time of the first normal time zone (start time of the fourth normal time zone) according to not only the outside air temperature but also the remaining hot water amount in the hot water tank 1. .
For example, when more hot water than usual is used in the third normal time zone, there is a possibility that the hot water in the hot water storage tank 1 usable in the fourth normal time zone is insufficient. Therefore, in such a case, the end time of the first normal time zone is deferred to shorten the length of the fourth normal time zone.
On the other hand, when the amount of hot water used in the third normal time zone is less than normal, there is a possibility that the hot water in the hot water storage tank 1 is greatly left. In such a case, the first normal time The length of the fourth normal time period may be increased by raising the end time of the band.

Further, the control unit 3 takes in a plurality of environmental factors such as atmospheric pressure and humidity in addition to the outside air temperature, and comprehensively determines whether or not the energy efficiency is equal to or higher than a predetermined standard based on these factors. Depending on the judgment result, how to use the heat pump hot water supply unit 2 may be determined.
For example, if it is estimated that the energy efficiency is higher than the standard, there is a benefit in utilizing the heat pump hot water supply unit 2, so the amount of hot water discharged from the heat pump hot water supply unit 2 can be increased even in the low-cost time zone. It is possible to advance the start time of the first daytime period or postpone the end time.

Further, the hot water valve 5 may alternatively discharge hot water from the hot water tank 1 and hot water from the heat pump hot water supply section 2 to the hot water pipe 7, for example, a ratio of 7 to 3, for example. The hot water may be controlled to be discharged at the same time.
For example, in the first normal time zone, hot water from the heat pump hot water supply unit 2 is selected and discharged to the hot water discharge pipe 7 in principle, but the remaining hot water amount in the hot water tank 1 at the end of the third normal time zone is When the amount is higher than normal, the hot water discharge valve 5 may be controlled so that hot water from the hot water storage tank 1 is simultaneously discharged in addition to hot water from the heat pump hot water supply section 2.
Thus, it is possible to construct an advanced and precise hot water supply apparatus by flexibly changing the hot water discharge method according to the amount of remaining hot water in the hot water storage tank 1 or the outside air temperature.

(Third embodiment)
Moreover, when the coefficient of performance COP (Coefficient of Performance) in the heat pump hot water supply unit 2 can be measured in real time, the control unit 3 may be operated according to the COP.

  For example, in a region where the electricity rate in the normal time zone is set to three times the electricity rate in the cheap hour zone, the control unit 3 has a coefficient of performance COP (Coefficient of Performance) of 3.0 or more. Only the heat pump hot water supply unit 2 should be used preferentially. This is because the heating efficiency per electricity rate is higher than when heating with a heater during a low-cost time zone.

In winter, for example, even when the COP is less than 3.0 (for example, 2.0 or more), the heat pump hot water supply unit 2 can be preferentially used. This is because in cold regions, there are cases where the temperature is low and the COP is not so high even during winter days.
In this case, the electricity bill may be less economical than when it is heated with a heater at night, but the heat pump hot water supply unit 2 should be used effectively in a cold region aiming for a time zone with high energy efficiency. Thus, the effect of reducing the total amount of CO2 emission can be obtained.

It should be noted that the value (COP threshold) for preferentially using the heat pump hot water supply unit 2 when the COP is more than that may be set in the storage unit of the control unit 3 in advance. It is desirable to be able to change the setting for each region or household.
Moreover, the control part 3 may be made to control based on both the temperature and COP value of outside air, and may be controlled based on the combination with time.

  For example, the control unit 3 constantly monitors the COP value from the time when noon has passed, and if the COP is 2.0 or more after noon, the heat pump hot water supply unit 2 is preferentially used. Even when a method is used in which the preferential use of the heat pump hot water supply unit 2 is terminated and the hot water in the hot water tank 1 is preferentially used when the COP becomes less than 2.0 after 2 pm. good.

  In addition, the control part 3 in this invention may be implement | achieved by one housing | casing, and may be implement | achieved by the combination of a some housing | casing. Each of these may be realized by one CPU, or may be realized by combining a plurality of CPUs. Moreover, it may be comprised with the hardware circuit which does not have CPU, an IC chip, etc., and the function which the control part 3 has may be implement | achieved by either hardware or software.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
For example, in FIG. 1, both hot water from the hot water storage tank 1 and hot water from the heat pump hot water supply unit 2 are discharged to one hot water pipe 7 through the hot water valve 5. May be provided for discharge. In this case, the control part 3 should just open and close each discharge valve according to a condition.

It is a schematic diagram which shows the outline | summary of apparatus arrangement | positioning of the hot water supply apparatus which concerns on this invention. It is a figure which shows an example of the time slot | zone which uses the heater 4, the hot water of the hot water tank 1, and the heat pump hot water supply part 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hot water tank 2 Heat pump type hot water supply part 3 Control part 4 Heater 5 Hot water discharge valve 6 Intake pipe 7 Hot water supply pipe

Claims (5)

A hot water storage tank equipped with a heater and a heat pump type hot water supply section are provided so that they can be operated in parallel, and commercial power that is set at a low-cost time zone where the predetermined time zone at night is cheaper than other time zones. A water heater used as a power source,
A control unit for controlling the operation of the hot water storage tank and the heat pump hot water supply unit,
In the low price period,
The control unit is configured to heat the hot water in the hot water storage tank with the heater and control the hot water in the hot water storage tank to be discharged preferentially over the hot water from the heat pump hot water supply unit,
In the first normal time zone out of the normal time zones other than the low-cost time zone,
The control unit is configured to stop the heating operation by the heater and to discharge the hot water from the heat pump hot water supply unit with higher priority than the hot water in the hot water storage tank,
In the second normal time zone other than the first normal time zone among the normal time zones,
The said control part is a hot water supply apparatus characterized by stopping the heating operation by the said heater, and controlling so that the hot water of the said hot water tank may be discharged | emitted preferentially rather than the hot water from the said heat pump type hot water supply part. The second normal time zone is
It is separated into a third normal time zone before the first normal time zone and a fourth normal time zone after the first normal time zone,
The first normal time zone is
The hot water supply apparatus according to claim 1, wherein the end time varies according to the amount of remaining hot water in the hot water storage tank at the end of the third normal time period. The hot water supply apparatus according to claim 1 or 2, wherein the first normal time zone is a time zone satisfying at least one of the following (1) and (2).
(1) Time zone in which the outside air temperature is higher than the predetermined first temperature (2) Time zone in which the coefficient of performance COP (Coefficient of Performance) in the heat pump hot water supply section is equal to or higher than a predetermined time Time zone starting from and until other time after noon In the low price period,
The hot water supply apparatus according to any one of claims 1 to 3, wherein the control unit increases or decreases a discharge amount of hot water from the heat pump hot water supply unit according to an outside air temperature. A hot water storage tank equipped with a heater and a heat pump type hot water supply section are provided so that they can be operated in parallel, and commercial power that is set at a low-cost time zone where the predetermined time zone at night is cheaper than other time zones. An operation method of a hot water supply device used as a power source,
The hot water supply apparatus includes a control unit that controls operations of the hot water storage tank and the heat pump hot water supply unit,
In the low price period,
Heating the hot water in the hot water storage tank with the heater, and operating the control unit to discharge the hot water in the hot water tank preferentially over the hot water from the heat pump hot water supply part,
In the first normal time zone out of the normal time zones other than the low-cost time zone,
The control unit stops the heating operation by the heater and operates the control unit so as to preferentially discharge the hot water from the heat pump hot water supply unit over the hot water in the hot water storage tank,
In the second normal time zone other than the first normal time zone among the normal time zones,
The control unit stops the heating operation by the heater and operates the control unit so that the hot water in the hot water storage tank is discharged preferentially over the hot water from the heat pump hot water supply unit. How the device works.

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