JP2003222396A - Heat pump type water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump type water heater capable of preventing hot water shortage and performing an economical operation by determining an optimum operating time for the use amount of hot water by users even if environmental conditions such as ambient temperature varies. <P>SOLUTION: This heat pump type water heater boils low temperature water by a heat pump heating source 2 and stores the boiled water in a hot water storage tank 3. The operating frequency of the compressor 25 of the heat pump heating source 2 is controlled based on the ambient temperature, the temperature of city water fed to the hot water storage tank 3, the temperature of the low temperature water, and the temperature of the hot water boiled by the heat pump heating source 2 so that a hot water heating capacity becomes generally constant. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump type water heater.

[0002]

2. Description of the Related Art Generally, a heat pump type water heater is shown in FIG.
As shown in, a tank unit 71 having a hot water storage tank 70 and a heat source unit 73 having a refrigerant circuit 72 are provided. Further, the refrigerant circuit 72 is configured by connecting a compressor 74, a water heat exchanger 75, an expansion valve 77 and an evaporator 78 in this order. The tank unit 71 includes the hot water storage tank 70 and a circulation path 79, and a water circulation pump 80 and a heat exchange path 81 are provided in the circulation path 79. In this case, the heat exchange passage 81 is composed of the water heat exchanger 75.

In the above apparatus, when the compressor 74 is driven and the pump 80 is driven (operated), stored water (hot water) flows out from the intake port provided at the bottom of the hot water storage tank 70 into the circulation path 79, This flows through the heat exchange passage 81.
At this time, this hot water is heated (boiled) by the water heat exchanger 75 and returned to the upper part of the hot water storage tank 70 from the hot water inlet. As a result, high-temperature hot water is stored in the hot water storage tank 70.

[0004]

By the way, this type of heat pump type hot water supply device has the property that when the operating frequency of the compressor is constant, the hot water heating capacity (boiling capacity) also decreases if the outside air temperature decreases. When the outside air temperature rises, the hot water heating capacity (boiling capacity) rises. In addition, the temperature of water entering the circulation path 79 from the hot water storage tank may change (rise) during the boiling operation. Generally, the refrigerant cycle of this type of heat pump heating source is shown by the solid line in FIG. 4, but if the temperature of the water entering the heat exchange passage 81 rises, the phantom line (two-dot chain line) in FIG. As shown in, the enthalpy difference in the heat dissipation process was narrowed, and the hot water heating capacity and COP were reduced.

As described above, in this type of heat pump type water heater, if the environmental conditions such as the outside air temperature and the incoming water temperature change, the capacity changes accordingly. If the ability changes, it is difficult to calculate the operation time for securing the amount of hot water corresponding to the user's use of hot water. That is,
If you know the ability, you can calculate the operating time to get the required amount of hot water, and if you drive for that operating time with that ability, you can boil the amount of hot water that corresponds to the usage amount of the user, If the ability is not known, the operating time for obtaining the required amount of hot water cannot be calculated, and it is difficult to boil the amount of hot water corresponding to the amount used by the user.
For example, when a certain amount of hot water can be boiled by operating for a certain time with a certain ability, if the ability decreases, the required amount of hot water cannot be boiled within the above predetermined time. For this reason, there is a possibility that hot water runs out due to lack of hot water, and conversely, even if the required amount of hot water is boiling, wasteful boiling operation may be continued, resulting in high running costs.

[0006] In recent years, the current power rate system is set so that the power rate unit price at midnight is lower than that at daytime.
In many cases, this operation is performed at a low night time (for example, a time period from 23:00 to 7:00) to reduce the running cost. Also, the hot water storage tank 70 is often designed to be small in consideration of the installation area and the like, and in such a case, the amount of hot water required for one day is small,
If the required amount of hot water can be stored in the hot water storage tank, the required amount of hot water is boiled up during the operation at midnight. When the required amount of hot water is large, additional operation during the daytime was performed in addition to the operation during the midnight hours.

Therefore, when the required amount of hot water for one day can be boiled in the midnight time and the hot water can be sufficiently stored in the hot water storage tank 70, that is, it can be boiled without using the entire midnight time. In this case, if the elapsed time after boiling is too long, the boiled water will cool, so operate for a certain time from a certain time in the midnight time zone (for example, 24:00 after the start of midnight time) Time end time,
That is, it is preferable to boil the required amount of hot water at 7:00 am. For this reason, if the operating time that is the predetermined time is not known, the boiling start time for ending boiling at the end time of the midnight time zone is not known, and the boiling end time may shift in the daytime. It was not possible to effectively use the midnight hours when the unit price was set at a low price. In addition, even when performing additional operation during the day, if the capacity fluctuates due to the outside air temperature, etc., this additional operating time is not known, and therefore the user operates during the daytime when the unit price of electricity is high. I didn't understand, and I was anxious.

The present invention has been made to solve the above-mentioned conventional drawbacks, and its object is to optimize the amount of hot water used by a user even when environmental conditions such as the outside air temperature change. An object of the present invention is to provide a heat pump type hot water supply device capable of determining an operating time, preventing the occurrence of hot water shortage, and enabling economical operation.

[0009]

Therefore, the heat pump type hot water supply apparatus of claim 1 is a heat pump type hot water supply apparatus in which low temperature water is boiled by the heat pump heating source 2 and stored in the hot water storage tank 3, and the heat pump heating source 2 is used. The operating frequency of the compressor 25 is controlled on the basis of the outside air temperature so that the hot water heating capacity is substantially constant.

In the heat pump type hot water supply apparatus according to the first aspect of the present invention, since the hot water heating capacity is substantially constant, it is possible to obtain the operating time for securing the required hot water amount. In this case, since the operating frequency of the compressor 25 of the heat pump heating source 2 may be controlled based on the outside air temperature, the control can be easily performed.

In the heat pump type water heater of claim 2, low temperature water is boiled by the heat pump heating source 2 and the hot water storage tank 3 is used.
A heat pump water heater for storing the heat pump heating source 2 based on the temperature of tap water supplied to the hot water storage tank 3 so that the hot water heating capacity of the compressor 25 becomes substantially constant. It is characterized by controlling.

In the heat pump type hot water supply apparatus according to the second aspect of the present invention, since the heating capacity is substantially constant, it is possible to obtain the operating time for securing the required amount of hot water. in this case,
Since the operation frequency of the compressor 25 of the heat pump heating source 2 may be controlled based on the temperature of the tap water, the control can be easily performed.

In the heat pump type hot water supply apparatus of claim 3, low temperature water is boiled by the heat pump heating source 2 to store the hot water in the hot water storage tank 3.
A heat pump water heater for storing in, characterized in that the operating frequency of the compressor 25 of the heat pump heating source 2 is controlled on the basis of the temperature of the low temperature water so that the hot water heating capacity becomes substantially constant. .

In the heat pump type hot water supply apparatus according to the third aspect of the present invention, since the heating capacity is substantially constant, it is possible to obtain the operation time for securing the required amount of hot water. in this case,
Since the operating frequency of the compressor 25 of the heat pump heating source 2 may be controlled based on the temperature of the low temperature water, the control can be easily performed.

In the heat pump type water heater of claim 4, low temperature water is boiled by the heat pump heating source 2 and the hot water storage tank 3 is used.
A heat pump hot water heater for storing the heat pump heating source 2 such that the operating frequency of the compressor 25 of the heat pump heating source 2 is set so that the hot water heating capacity is substantially constant.
It is characterized in that it is controlled based on the temperature of the hot water boiled in.

In the heat pump type hot water supply apparatus according to the fourth aspect of the present invention, since the heating capacity is a substantially constant capacity, the operating time for securing the required amount of hot water can be obtained. in this case,
Since the operating frequency of the compressor 25 of the heat pump heating source 2 may be controlled based on the temperature of the hot water boiled by the heat pump heating source 2, the control can be easily performed.

In the heat pump type hot water supply apparatus of claim 5, low temperature water is boiled by the heat pump heating source 2 to store the hot water in the hot water storage tank 3.
A heat pump water heater for storing the operating frequency of the compressor of the heat pump heating source 2 such that the temperature of the outside air, the temperature of tap water supplied to the hot water storage tank 3, The control is based on at least two types of temperatures of the low-temperature water and the temperature of the hot water boiled by the heat pump heating source 2.

In the heat pump type hot water supply apparatus according to the fifth aspect of the present invention, since the heating capacity is substantially constant, it is possible to obtain the operating time for securing the required amount of hot water. in this case,
Control is performed based on at least two types of temperatures of the outside air temperature, the temperature of tap water supplied to the hot water storage tank 3, the temperature of the low temperature water, and the temperature of the hot water boiled by the heat pump heating source 2. Therefore, it is possible to reliably perform the operation with substantially constant capacity.

In the heat pump type hot water supply apparatus of claim 6, the heat pump heating source 2 is a compressor 25 and a water heat exchanger 26.
A heat pump type hot water supply device having a decompression mechanism 27 and an air heat exchanger 28, and having a fan 34 in the air heat exchanger 28, wherein the fan is used in an operation in which the hot water heating capacity is substantially constant. The rotation speed of 34 is controlled based on any of the outside air temperature, the temperature of tap water supplied to the hot water storage tank 3, the temperature of the low temperature water, and the temperature of the hot water boiled by the heat pump heating source 2. It has a feature.

In the heat pump type hot water supply apparatus according to the sixth aspect of the present invention, since the heating capacity is substantially constant, it is possible to obtain the operating time for securing the required amount of hot water. in this case,
The rotation speed of the fan 34 is controlled based on the outside air temperature, the temperature of the tap water supplied to the hot water storage tank 3, the temperature of the low temperature water, or the temperature of the hot water boiled by the heat pump heating source 2. Therefore, it is possible to perform highly accurate operation with substantially constant capacity.

The heat pump type hot water supply apparatus according to claim 7 is characterized in that a supercritical refrigerant used in supercritical is used as the refrigerant.

In the heat pump type hot water supply apparatus according to the seventh aspect, by using the supercritical refrigerant, if the temperature of the low temperature water (inlet temperature) heated by the heat pump heating source rises, the hot water heating capacity and COP decrease. Because there is a feature that
Each of the above-mentioned actions is prominent. Also, destruction of the ozone layer,
It is a heat pump type water heater that is friendly to the global environment without problems such as environmental pollution.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Next, specific embodiments of the heat pump water heater of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a simplified diagram of this heat pump water heater, which heats low-temperature water by a heat pump heating source 2 and stores it in a hot water storage tank 3. The hot water is stored in this hot water storage tank 3. Hot water is supplied to a bath or the like (not shown). That is, the hot water storage tank 3 is provided with a water supply port 5 on its bottom wall and a hot water outlet 6 on its upper wall. Then, tap water is supplied from the water supply port 5 to the hot water storage tank 3, and high-temperature hot water is discharged from the hot water outlet 6. Further, in the hot water storage tank 3, a water intake 10 is opened in the bottom wall thereof, and a hot water inlet 11 is opened in the upper part of the side wall (peripheral wall), so that the hot water intake 10 and the hot water inlet 11 are connected by a circulation path 12. Has been done. A water circulation pump 13 and a heat exchange passage 14 are provided in the circulation passage 12. A water supply channel 8 is connected to the water supply port 5.

By the way, in the hot water storage tank 3, four remaining hot water amount detectors 18a, 18b, 18 are arranged at a predetermined pitch in the vertical direction.
c and 18d, and a temperature detector 19a that constitutes a supply water temperature detecting means 19 described later are provided. Each of the remaining hot water amount detectors 18a, ... And the temperature detector 19a are, for example, a thermistor. Further, the circulation path 12 is provided with an incoming water thermistor 20a on the upstream side of the heat exchange path 14 and an outlet hot water thermistor 21a on the downstream side of the heat exchange path 14.

The heat pump heating source 2 has a refrigerant circuit, and the refrigerant circuit includes a compressor 25 and a heat exchange passage 14.
Water heat exchanger 26, which constitutes a motor, and an electric expansion valve (pressure reducing mechanism)
27 and an air heat exchanger (evaporator) 28 are connected in this order. That is, the discharge pipe 29 of the compressor 25 is connected to the water heat exchanger 26, and the water heat exchanger 26 and the electric expansion valve 27 are connected.
Are connected by a refrigerant passage 30, the electric expansion valve 27 and the evaporator 28 are connected by a refrigerant passage 31, and the evaporator 28 and the compressor 25 are connected by an accumulator 32.
3 is connected. Further, the evaporator 28 is provided with a fan 34 for adjusting the capacity of the evaporator 28. Further, the heat pump heating source 2 is provided with an outside air temperature detecting thermistor 36a for detecting the outside air temperature. Then, a supercritical refrigerant (for example, carbon dioxide gas) used in a supercritical state was used as the refrigerant.

By the way, as shown in FIG. 2, the control unit of this heat pump type hot water supply system has a residual hot water amount detecting means 37, an outside air temperature detecting means 36, an incoming water temperature detecting means 20, a hot water outlet temperature detecting means 21, and A water supply temperature detecting means 19 for detecting the temperature of tap water supplied to the hot water storage tank 3, a setting means 39 for setting an operating frequency of the compressor 25, etc., as described later,
And a control means 38 to which data (numerical values) and the like from the respective detection means 19, 20, 21, 36 and 37 are input. In this case, as shown in FIG. 1, the remaining hot water amount detecting means 37 includes the remaining hot water amount detectors 18a, 18b, 1 attached to the hot water storage tank 3.
8c, 18d, the outside air temperature detecting means 36 can be formed by an outside air temperature thermistor 36a, the incoming water temperature detecting means 20 can be formed by an incoming water thermistor 20a, and the hot water outlet temperature detecting means The hot water supply thermistor 21a can be constituted by 21, and the feed water temperature detecting means 19 can be constituted by a temperature detector 19a.
The control means 38 can be configured by using, for example, a microcomputer.

According to the heat pump type hot water supply device constructed as described above, when the compressor 25 is driven and the water circulation pump 13 is driven (operated), the water intake port 10 provided at the bottom of the hot water storage tank 3 is driven. The stored water (low temperature water) flows out, and this flows through the heat exchange passage 14 of the circulation passage 12. At this time, this hot water is heated (boiled) by the water heat exchanger 26 and returned from the hot water inlet 11 to the upper part of the hot water storage tank 3. By continuing this kind of operation,
Hot hot water can be stored in the hot water storage tank 3. In this case, since the current power rate system is set so that the power rate unit price at midnight is lower than that at daytime, this operation is low at midnight hours (for example, from 23:00 to 7:00). Is what you do.

That is, a certain time (for example, 2 after the start of the midnight time) of the midnight time (from 23:00 to 7:00 am of the next day) band.
It is operated for a predetermined time from 4 o'clock, etc., and performs a boiling operation of boiling a predetermined amount of hot water (for example, the capacity of the hot water storage tank 3) at a predetermined time (midnight time end time, that is, 7:00 am). is there. In addition, if the required amount of hot water for one day exceeds the capacity of the hot water storage tank 3, after operating at midnight, additional operation is performed during the daytime outside of midnight to secure the required amount of hot water for the day. To do. In this case, if a predetermined amount (for example, 50 liters) of hot water is used when the amount of hot water filling the capacity of the hot water storage tank 3 is boiled and the stored hot water amount decreases, the reduced predetermined amount The additional operation of boiling the hot water is performed, and the required amount of hot water for the day is secured by performing the additional operation at least once. In the boiling operation, the start or stop of the operation is determined based on the detected values of the remaining hot water amount detector 18a, the water entering thermistor 20a, and the like.

In the heat pump type hot water supply device, when the operating frequency of the compressor 25 is constant, if the outside air temperature decreases, the hot water heating capacity (boiling capacity) also decreases, and conversely if the outside air temperature rises. Hot water heating capacity (boiling capacity) increases. That is, as shown in FIG. 3, for example, when the outside air temperature is about 5 ° C., the operating frequency of the compressor 25 is set to 75H.
If it is about z, the capacity (hot water heating capacity) becomes 4.5 kw (so-called rated capacity), but if the operating temperature is not increased if the outside air temperature decreases, 4.5 kw cannot be maintained. If the outside air temperature rises, it is possible to maintain 4.5 kw by lowering the operating frequency.
Further, if the incoming water temperature rises, the hot water heating capacity decreases.
Therefore, in response to these environmental conditions such as outside temperature,
The operating frequency of the compressor 25 at the time of boiling can be determined as shown in Table 1 below so that the hot water heating capacity becomes substantially constant. In this case, the hot water temperature (hot water thermistor 21
When the temperature is a and the temperature of the hot water boiled by the heat pump heating source 2 is a predetermined temperature (for example, 75 ° C.), the outside air temperature and the incoming water temperature (the incoming water thermistor 2)
Based on environmental conditions such as the temperature of 0a and the temperature of the low-temperature water before being boiled by the heat pump heating source 2)
By determining (setting) the operating frequency of the compressor 25 and performing the boiling operation at this operating frequency set for each environmental condition, the hot water heating capacity becomes substantially constant. For example, as the hot water heating capacity, the operation of the rated capacity of 4.5 kw is possible. The opening degree of the electric expansion valve 27 is determined based on the operating frequency and the outside air temperature.

[0030]

[Table 1]

Further, in Table 1, the outside air temperature is divided into seven modes of the seasonal mode 1 to the seasonal mode 7, and the incoming water temperature is divided into seven modes of the incoming water mode 1 to the incoming water mode 7.
For example, seasonal mode 1 is 5 ° C. or lower, seasonal mode 2 is 5 ° C. or higher and 9 ° C. or lower, seasonal mode 3 is 9 ° C. or higher and 13 ° C. or lower, and seasonal mode 4 is 13 ° C. or higher and 18 ° C. Seasonal mode 5 exceeds 18 ° C and 2
3 ℃ or less, seasonal mode 6 exceeds 23 ℃ and 28 ℃
In the following, seasonal mode 7 is set to exceed 28 ° C. In addition, the water entry mode 1 is set to 5 ° C or lower, and the water entry mode 2 is set.
Above 5 ° C and below 10 ° C, and set water entry mode 3 to 10
Above 15 ° C and below 15 ° C, water entering mode 4 above 15 ° C and below 20 ° C, water entering mode 5 above 20 ° C and below 27 ° C, and water entering mode 6 above 27 ° C and below 33 ° C. The water entry mode 7 is set to exceed 33 ° C. The temperature of tap water is 33 ° C even in summer.
Since there is almost no case where the temperature exceeds the above, the standard for water entry mode 7 is 33 ° C.

For example, the operating frequency of the compressor 25 is set to 85 Hz in the season mode 1 and the water entry mode 1, 90 Hz in the season mode 1 and the water entry mode 7, and the season mode 7 And in the water entry mode 1, the frequency is set to 45 Hz, and in the seasonal mode 7 and the water entry mode 1, the frequency is set to 50 Hz. In this case, in each season mode, the operating frequency increases as the mode increases from water entry mode 1, and in each water entry mode the operating frequency decreases as the mode increases from seasonal mode 1. That is, the operating frequency of the compressor 25 is decreased as the outside air temperature is increased, and the operating frequency of the compressor 25 is increased as the incoming water temperature is increased. In each season mode, when the operating frequency is increased as the mode increases from the water entry mode 1, the operation frequency may be changed for each water entry mode, or the several modes may have the same frequency. In addition, in each water entry mode, seasonal mode 1
When decreasing the operating frequency as the number of modes increases, it is preferable to change the frequency for each seasonal mode.

By the way, in Table 1 above, the tapping temperature is, for example, 7
When the hot water temperature is 5 ° C. and the hot water temperature is higher than that in Table 1, for example, when the hot water temperature is 85 ° C., the hot water temperature is increased by 2 Hz, for example, from each data (numerical value) in Table 1, and the hot water temperature is When the temperature is lower than that in Table 1, for example, when the temperature is 65 ° C., the data (numerical value) in Table 1 is, for example, 2H.
By lowering by z, the ability can be made substantially constant. That is, by setting data according to the hot water temperature and operating according to this data, the capacity can be made substantially constant at the hot water temperature.

Therefore, in this heat pump type water heater,
The data shown in Table 1 above, the data raised from the data shown in Table 1 by 2 Hz, and the data lowered from the data shown in Table 1 by 2 Hz are set by the setting means 3, and these data (set data) are set. Is input to the control means 38. Then, the outside air temperature, the incoming water temperature, and the outgoing hot water temperature are detected, these detection data are input to the control means 38, and the control means 38 determines the operating frequency of the setting data corresponding to these detection data, and at this operating frequency So,
Perform boiling operation. As a result, the operating frequency is changed (controlled) according to changes in the outside air temperature, the incoming water temperature, and the outgoing hot water temperature, and it is possible to perform operation with a substantially constant capacity.

As described above, since the capacity does not change in accordance with the change of the environmental condition and the operation can be performed with a substantially constant capacity, it is possible to obtain the operation time when the required amount of hot water is secured. That is, when boiling a predetermined amount of hot water in the above-mentioned midnight time zone, determine the operation start time, start the operation from that time, and boil at the midnight time end time, that is, 7:00 am can do. Further, since it is possible to obtain the operating time when securing the required amount of hot water, it is possible to reliably secure the usage amount of the user, it is possible to prevent the occurrence of shortage of hot water, and
It is possible to avoid useless driving after securing the usage amount of the user, and prevent an increase in running cost.

By the way, in the case of an operation in which the hot water heating capacity is kept substantially constant, the supply water temperature (the temperature of tap water) may be used instead of the outside air temperature. This is because the temperature of the tap water is approximately the same as or proportional to the outside air temperature, so even if the operating frequency is controlled based on the temperature of this tap water, the hot water heating capacity can be operated at a substantially constant capacity. Because you can. Therefore, when performing an operation in which the hot water heating capacity is approximately constant,
The operating frequency of the compressor of the heat pump heating source is the outside air temperature, the temperature of tap water supplied to the hot water storage tank 3, the temperature of the low-temperature water (inlet temperature), and the temperature of hot water boiled by the heat pump heating source ( It is possible to control the temperature based on any one of the tapping temperatures), and it is preferable to control based on two or more of these temperatures.
If two or more types are used, the amount of input data increases, and more reliable and highly accurate control can be performed.

Further, when performing an operation in which the hot water heating capacity is substantially constant, the rotation speed of the fan 34 attached to the air heat exchanger 28 may be controlled based on the outside air temperature or the like. In this case, the number of rotations shown in Table 2 below is set.

[0038]

[Table 2]

Also in Table 2, as in the case of Table 1, there are a season mode 1 to a season mode 7, a water entry mode 1 to a water entry mode 7, and a predetermined rotation speed is entered in each column. For example, if the RSR11 that is in the seasonal mode 1 and the water entry mode 1 is 57
It is set to 0 rpm, and RSR77 which is the season mode 7 and the water entry mode 7 is set to 470 rpm. In this case, the rotation speed of the fan 34 decreases as the outside air temperature increases,
The rotation speed of the fan 34 tends to increase as the incoming water temperature rises.

As described above, if the rotation frequency of the fan 34 is controlled on the basis of the outside air temperature and the incoming water temperature in addition to the operating frequency of the compressor 25, it is possible to obtain a constant capacity with higher accuracy and to perform an accurate operation. I can grasp the time. As a result, the reliability of preventing hot water outage and cost reduction is improved.

Although the specific embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention. For example, when controlling the rotation speed of the fan 34, as shown in Table 2, the temperature of the tap water (water supply temperature) supplied to the hot water storage tank 3 and the heat pump heating source are not limited to those based on the outside air temperature and the incoming water temperature. The control may be performed based on the temperature of hot water boiled in 2 (outlet temperature). Further, the operating frequency and the rotation speed of the fan 34 in each mode can be changed according to the set capability and the like. Furthermore, the temperature range and the number of modes for each season mode and each water entry mode can be freely changed. Further, the heat pump type hot water supply apparatus of the above-described embodiment includes the hot water storage tank 3, the circulation path 12 connected to the hot water storage tank 3, and the heat exchange path 14 interposed in the circulation path 12. It is possible to heat the exchange passage 14 with a heat pump heating source to boil the low temperature water flowing from the lower portion of the hot water storage tank 3 to the circulation passage 12 and discharge the hot water to the upper portion of the hot water storage tank 3, and at the same time, to operate the heat pump. The refrigerant circulation circuit of the heating source includes a compressor 25, a water heat exchanger 26 that heats the low-temperature water,
The decompression mechanism 27 and the air heat exchanger 28 are sequentially connected, but as a heat pump type water heater, low temperature water is boiled by the heat pump heating source 2 and the hot water storage tank 3 is used.
As long as it can be stored in
Need not have. That is, the heat pump heating source 2
The low temperature water for boiling up may be supplied from other than the hot water storage tank 3. Further, by using carbon dioxide gas as the refrigerant of the refrigerant circuit, if the temperature of the low temperature water heated by the heat pump heating source (inlet temperature) rises, the hot water heating capacity and COP are reduced, so It is preferable because the unique action and effect such as the form of (2) above appears remarkably. In addition, as a refrigerant, in addition, dichlorodifluoromethane (R-12) and chlorodifluoromethane (R-2)
Even a refrigerant such as 2) may be an alternative refrigerant such as 1,1,1,2-tetrafluoroethane (R-134a) due to problems such as ozone layer destruction and environmental pollution.

[0042]

According to the heat pump type hot water supply apparatus of the present invention, since the operating time for securing the required hot water amount can be obtained, it becomes easy to secure the required hot water amount, and the shortage of hot water can be prevented. This can be prevented, and the user can use the hot water with peace of mind. In addition, since it is possible to prevent wasteful operation after securing the required amount of hot water, it is possible to reduce running costs. Further, when a predetermined amount of hot water can be boiled in the midnight time period, the operating time is known, so the boiling start time for ending the boiling at the midnight time end time (for example, 7:00 am) Can be calculated, and it is possible to effectively use the midnight time period when the unit price of electric power is set to be low. In addition, it is possible to know the operation time of the additional operation in the daytime to secure the required amount of hot water, and it is possible to grasp the power consumption during the daytime when the power unit price is high. it can. Then, in order to make the hot water heating capacity almost constant, it is sufficient to detect the outside air temperature.
The control is simple, and the existing heat pump water heater can be used as it is, which is economical.

According to the heat pump type hot water supply apparatus of claims 2 to 4, the required amount of hot water can be secured and the occurrence of shortage of hot water can be prevented, like the heat pump type hot water supply apparatus of claim 1. Therefore, the user can use the hot water without anxiety. In addition, since it is possible to prevent wasteful operation after securing the required amount of hot water, it is possible to reduce running costs. In order for the hot water heating capacity to be substantially constant, the temperature of tap water in the heat pump water heater of claim 2, the temperature of low-temperature water in the heat pump water heater of claim 3, and the boiling of the heat pump water heater in claim 4. Since the temperature of the heated hot water is detected, each control is simple and the existing heat pump water heater can be used as it is, which is economical.

According to the heat pump type hot water supply apparatus of claim 5, it is possible to surely carry out the operation with a substantially constant capacity, so that it is possible to surely know the operation time for securing the necessary amount of hot water. , While eliminating the anxiety of running out of water,
Economically safe driving becomes possible.

According to the heat pump type water heater of claim 6, the operation with substantially constant capacity can be performed with high accuracy,
As a result, the required amount of hot water can be reliably secured, and unnecessary boiling operation can be avoided, so that economically safe operation can be performed.

According to the heat pump type hot water supply apparatus of claim 7, when the temperature of the low temperature water (inlet temperature) heated by the heat pump heating source rises by using the supercritical refrigerant, the hot water heating capacity and COP are improved. Since there is a feature that decreases,
The above-mentioned respective effects are remarkably exhibited. Also, destruction of the ozone layer,
It is a heat pump type water heater that is friendly to the global environment without problems such as environmental pollution.

[Brief description of drawings]

FIG. 1 is a simplified diagram showing an embodiment of a heat pump type hot water supply device of the present invention.

FIG. 2 is a simplified block diagram of a control unit of the heat pump water heater.

FIG. 3 is a graph showing the relationship between the capacity of the heat pump water heater, the operating frequency of the compressor, and the outside air temperature.

[Fig. 4] Fig. 4 is a refrigeration cycle diagram for explaining a problem in the case where the water input of a conventional heat pump water heater rises.

FIG. 5 is a simplified view of a conventional heat pump water heater.

[Explanation of symbols]

2 Heat pump heating source 3 hot water storage tank 25 compressor 26 Water heat exchanger 27 Decompression mechanism 28 Air heat exchanger 34 fans

Claims (7)

[Claims] 1. A heat pump water heater for boiling low temperature water in a heat pump heating source (2) and storing it in a hot water storage tank (3), the operating frequency of a compressor (25) of the heat pump heating source (2). Is controlled on the basis of the outside air temperature so that the hot water heating capacity is substantially constant. 2. A heat pump water heater for boiling low-temperature water in a heat pump heating source (2) and storing it in a hot water storage tank (3), wherein an operating frequency of a compressor (25) of the heat pump heating source (3). Is controlled on the basis of the temperature of the tap water supplied to the hot water storage tank (3) so that the hot water heating capacity becomes substantially constant. 3. A heat pump water heater for boiling low-temperature water in a heat pump heating source (2) and storing it in a hot water storage tank (3), the operating frequency of a compressor (25) of the heat pump heating source (3). Is controlled based on the temperature of the low-temperature water so that the hot water heating capacity is substantially constant. 4. A heat pump water heater for boiling low temperature water in a heat pump heating source (2) and storing it in a hot water storage tank (3), the operating frequency of a compressor (25) of the heat pump heating source (2). Is controlled on the basis of the temperature of the hot water boiled by the heat pump heating source (2) so that the hot water heating capacity becomes substantially constant. 5. A heat pump water heater for boiling low-temperature water in a heat pump heating source (2) and storing it in a hot water storage tank (3), the operating frequency of a compressor (25) of the heat pump heating source (2). The hot water boiled by the outside air temperature, the temperature of the tap water supplied to the hot water storage tank (3), the temperature of the low temperature water, and the heat pump heating source (2) so that the hot water heating capacity becomes substantially constant. A heat pump water heater characterized by being controlled based on at least two kinds of temperatures among the above. 6. The heat pump heating source (2) comprises a compressor (25), a water heat exchanger (26), and a pressure reducing mechanism (27).
And a heat exchanger (28) and a fan (34) in the air heat exchanger (28), the heat pump water heater having a substantially constant capacity for heating the hot water. The rotation speed of the fan (34) is one of the outside air temperature, the temperature of tap water supplied to the hot water storage tank (3), the temperature of the low temperature water, and the temperature of hot water boiled by the heat pump heating source (2). The heat pump water heater according to any one of claims 1 to 5, which is controlled based on 7. The heat pump water heater according to claim 1, wherein a supercritical refrigerant used in a supercritical condition is used as the refrigerant.