JP2005351588A - Heat pump water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump water heater capable of preparing the hot water of high temperature for supplying the hot water with high efficiency without rising a discharge temperature of a compressor. <P>SOLUTION: This heat pump water heater comprises a refrigerant circuit constituted by successively connecting at least the compressor 31, a radiator 32, a main throttling device 33 and an evaporator 34, and the refrigerant circuit is provided with an auxiliary heat exchanger 37 for exchanging the heat between a refrigerant between the main throttling device 33 and the evaporator 34 and a refrigerant between the evaporator 34 and the compressor 31. As a refrigerant superheat degree in suction of the compressor 31 can be lowered while keeping high refrigerant superheat degree at an outlet of the evaporator 34, the capacity of the evaporator can be maximized while preventing the excess rise of the discharge temperature of the compressor 31, and high operation performance of the heat pump water heater can be kept. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a configuration of a heat pump water heater and an operation method thereof.

  Conventionally, this type of heat pump hot water supply apparatus is shown in FIG. FIG. 3 is a cycle diagram illustrating a heat pump water heater as an example of a conventional heat pump water heater. In FIG. 3, a refrigerant circulation circuit comprising a compressor 1, a hot water supply heat exchanger 2, an expansion device 3 and an evaporator 4, a hot water storage tank 5, a circulation pump 6, the hot water supply heat exchanger 2 and an auxiliary heater 19 are provided. The high-temperature and high-pressure superheated gas refrigerant discharged from the compressor 1 flows into the hot water supply heat exchanger 2 and heats the hot water supplied from the circulation pump 6.

The condensed and liquefied refrigerant is decompressed by the expansion device 3 and flows into the evaporator 4, where it absorbs atmospheric heat to evaporate and returns to the compressor 1. On the other hand, the hot water heated by the hot water supply heat exchanger 2 flows into the upper part of the hot water storage tank 5 and is gradually stored from above. When the inlet water temperature of the hot water supply heat exchanger 2 reaches a set value, the water temperature detector 20 detects it, stops the heat pump operation by the compressor 1, and switches to the independent operation of the auxiliary heater 19. Yes (see, for example, Patent Document 1).
JP 60-164157 A

  Usually, in the operation of the heat pump, since the operation performance of the heat pump is improved by performing the operation of completely evaporating the two-phase refrigerant flowing in the evaporator 4, the refrigerant at the outlet of the evaporator 4 is considered in consideration of the evaporation delay of the refrigerant. When the degree of superheat is usually 3 to 5K or more, the evaporation capability can be maximized and the operation performance is improved.

  However, in the conventional configuration as described above, when the refrigerant temperature at the outlet of the evaporator 4 is substantially equal to the intake gas temperature of the compressor 1 and the refrigerant superheat degree at the outlet of the evaporator 4 is set to 3 to 5K or more, The suction refrigerant superheat degree of the compressor 1 has a similar value.

  However, as in these heat pump water heaters, when hot water is generated, it is necessary to raise the refrigerant temperature of the hot water heat exchanger 2, and the discharge pressure of the compressor 1 becomes high, causing compression. As a result, the discharge temperature of the compressor 1 is increased, and therefore, when the superheat degree of the refrigerant sucked by the compressor 1 is increased, the discharge temperature of the compressor 1 is excessively increased and the reliability of the compressor 1 is impaired.

  On the other hand, if the discharge temperature of the compressor 1 is set to a certain value or less, the refrigerant superheat degree at the outlet of the evaporator 4 cannot be increased, and in some cases, the outlet of the evaporator 4 remains in a two-phase state, causing evaporation. The capacity of vessel 4 could not be fully exploited.

  Further, since the refrigerant temperature at the outlet of the evaporator 4 cannot be brought close to the heat source fluid (for example, air) temperature, the refrigerant temperature in the evaporator 4 becomes substantially constant, and the refrigerant flow in the evaporator 4 and the heat source fluid (for example, air) ), Even if the flow was substantially counterflow, the effect was hardly obtained.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object of the present invention is to provide a heat pump hot water supply apparatus that can generate a hot water supply water temperature and the like with high efficiency without increasing the discharge temperature of the compressor.

  In order to solve the conventional problems, a heat pump hot water supply apparatus of the present invention includes a refrigerant circuit by sequentially connecting at least a compressor, a radiator, a main throttle device, and an evaporator, and the main throttle device is provided in the refrigerant circuit. And an auxiliary heat exchanger for exchanging heat between the refrigerant between the evaporator and the refrigerant between the evaporator and the compressor, and increasing the refrigerant superheat degree at the outlet of the evaporator Since the refrigerant superheating degree of the compressor suction can be lowered, the evaporator performance can be maximized while preventing the compressor discharge temperature from rising excessively, and the operating performance of the heat pump water heater can be improved. Can be kept high.

  ADVANTAGE OF THE INVENTION According to this invention, the heat pump hot-water supply apparatus which can produce | generate the hot water supply water temperature etc. of high efficiency and high temperature without the discharge temperature rise of a compressor can be provided.

  A first invention includes a refrigerant circuit in which at least a compressor, a radiator, a main throttle device, and an evaporator are sequentially connected, and the refrigerant circuit includes a refrigerant between the main throttle device and the evaporator and the evaporator. And an auxiliary heat exchanger for exchanging heat between the refrigerant and the refrigerant between the compressors, and the refrigerant sucked into the compressor is an auxiliary heat exchanger while the refrigerant superheat degree at the outlet of the evaporator is increased. Heat exchange with a low-temperature refrigerant at low temperature and the degree of refrigerant superheat can be reduced, so that the evaporator discharge capacity can be maximized while preventing the discharge temperature of the compressor from rising excessively. The operating performance of the heat pump water heater can be maintained high.

  According to a second aspect of the present invention, the refrigerant flowing through the evaporator and the heat source side fluid that exchanges heat with the evaporator are configured to flow in a substantially counterflow, and the refrigerant at the outlet of the evaporator When the degree of superheat is increased, a counter flow that lowers the temperature of the heat source side fluid is possible with respect to the temperature rise of the refrigerant, making it possible to bring the evaporation temperature of the evaporator closer to the heat source temperature, and the suction pressure of the compressor As a result, the compression power in the compressor is reduced, and the performance of the heat pump water heater can be improved.

  The third invention is characterized in that the refrigerant flowing through the radiator and the load-side fluid that exchanges heat with the radiator are configured to flow in a substantially countercurrent flow. On the other hand, it is possible to perform a counter flow that raises the temperature of the heat source side fluid, making it possible to bring the heat dissipation temperature of the radiator closer to the heat source temperature, reducing the compressor discharge pressure and reducing the compression power in the compressor. The performance of the heat pump water heater improves.

  According to a fourth aspect of the invention, the opening degree of the main throttle device and / or the operating frequency of the compressor is controlled so that the degree of superheat of the outlet refrigerant of the evaporator is larger than a preset value. Thus, the refrigerant superheat degree at the outlet of the evaporator can be reliably controlled to a value that improves the operation performance of the heat pump water heater.

  According to a fifth aspect of the present invention, there is provided an evaporation temperature sensor that detects an evaporation temperature of the evaporator and an evaporator outlet temperature sensor that detects an outlet refrigerant temperature of the evaporator, and the temperature detected by the evaporator outlet temperature sensor and the evaporation It is characterized by controlling the opening of the main throttle device and / or the operating frequency of the compressor so that the temperature difference from the temperature detected by the temperature sensor is greater than a preset value, The evaporating temperature can be detected from the refrigerant temperature in the evaporator, the refrigerant superheat degree at the outlet of the evaporator can be detected with high accuracy, and the operation performance of the heat pump water heater can be reliably controlled. .

According to a sixth aspect of the present invention, there is provided a discharge temperature sensor for detecting a refrigerant temperature discharged from the compressor, and the opening degree of the main throttle device and / or the temperature of the discharge temperature sensor become a preset discharge temperature value. Or, it is characterized by controlling the operating frequency of the compressor, especially in the case of operation where the high pressure rises, while the discharge temperature of the compressor is controlled safely and the capacity of the evaporator is maximized. And the operating performance of the heat pump water heater is improved.

  The seventh invention is characterized by comprising a hot water supply circuit in which at least a hot water storage tank and a radiator are sequentially connected as a heat source side of the radiator, and preventing the discharge temperature of the compressor from being excessively increased, In particular, high-temperature hot water can be easily generated while maintaining high operating performance of the heat pump hot water supply device without impairing reliability.

  The eighth invention is characterized in that carbon dioxide gas is used as a refrigerant, and it is possible to increase the temperature of hot water supply with high efficiency, and also to affect global warming even when the refrigerant leaks to the outside. Are very few.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments. In addition, in each Example, the same code | symbol is provided about the part which has the same structure and the same operation | movement, and detailed description is abbreviate | omitted.

(Embodiment 1)
FIG. 1 shows a configuration diagram of a heat pump hot water supply apparatus and a control method thereof according to the first embodiment of the present invention.

  In FIG. 1, a compressor 31, a radiator 32, a main throttle device 33, and an evaporator 34 are sequentially connected in an annular form, and carbon dioxide gas is sealed as a refrigerant to form a refrigerant circulation circuit. The evaporator 34 blows outside air. The high-temperature and high-pressure superheated gas refrigerant discharged from the compressor 31 flows into the radiator 32, and the air sent from the fan 36 for blowing air as a load is used here. It is designed to heat.

Furthermore, the piping between the main expansion device 33 and the evaporator 34 and the piping between the evaporator 34 and the compressor 31 are indirectly heat-exchanged via an auxiliary heat exchanger 37.
The radiator 32 is a fin-tube heat exchanger. The tube (tube) 38 constituting the fin tube has a refrigerant flow (in the direction of the wavy arrow in the figure) and an air flow (in the direction of the solid arrow in the figure). In contrast, the flow is substantially opposite. Further, the evaporator 34 is also a fin tube type heat exchanger, and the refrigerant flow (in the direction indicated by the wavy arrow in the figure) of the tube (tube) 39 constituting the fin tube is the flow of outside air (in the direction indicated by the solid arrow in the figure). In contrast, the flow is substantially opposite.

  Furthermore, an evaporation temperature sensor 40 for detecting the evaporation temperature of the evaporator 34 and an evaporator outlet temperature sensor 41 for detecting the outlet refrigerant temperature of the evaporator 34 are provided. The temperature detected by the evaporator outlet temperature sensor 41 and the evaporation temperature are provided. A control device 42 for controlling the opening of the main throttle device 33 is provided so that the temperature difference from the temperature detected by the sensor 40 (that is, the degree of refrigerant superheat at the outlet of the evaporator 34) becomes larger than a preset value. ing. Further, carbon dioxide gas is sealed as the refrigerant.

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

The refrigerant (carbon dioxide gas) compressed into the supercritical state of high temperature and high pressure by the compressor 31 exchanges heat with the air sent from the fan 36 for blowing air as a load in the radiator 32. It becomes a medium temperature and high pressure refrigerant. On the other hand, the radiator 32 is a fin tube type heat exchanger, and the tube (tube) 38 constituting the fin tube generally flows in the direction of the wavy arrow in the figure while the refrigerant flow meanders, and the temperature is increased. It gradually decreases. On the other hand, the air flow as a load is heat-exchanged by the fan 36, the temperature gradually increases in the direction of the solid arrow in the figure, and the refrigerant flow and the air flow are substantially opposite flows. In addition, since the flow becomes temperature efficient from the air side, the heat exchange efficiency is improved.

  The refrigerant exiting the radiator is decompressed by the main expansion device 33 and then flows into the auxiliary heat exchanger 37. Here, the refrigerant is a low-temperature and low-pressure two-phase refrigerant. Further, the refrigerant flows into the evaporator 34, where it exchanges heat with the outside air blown by the fan 35 to be evaporated into gas. Then, the refrigerant that has exited the evaporator 34 flows into the auxiliary heat exchanger, where it indirectly exchanges heat with the refrigerant that has exited the main throttle device 33 and is then sucked into the compressor 31 again.

  Here, the control device 42 determines the difference between the refrigerant temperature detected by the evaporator outlet temperature sensor provided at the outlet of the evaporator 34 and the evaporation temperature detected by the evaporation temperature sensor 40 provided in the middle of the evaporator 34 pipe. The temperature (that is, the degree of superheat of the outlet refrigerant of the evaporator 34) is calculated, and if it is not more than a preset value (for example, 5K), the opening of the main expansion device 33 is operated in the closing direction. By doing so, the flow resistance in the main throttle device 33 increases, the refrigerant circulation amount to the evaporator 34 decreases, and the outlet refrigerant superheat degree of the evaporator 34 increases. And the opening degree of the main expansion device 33 is controlled so that it becomes more than a preset value (for example, 5K). By doing so, the temperature of the tube 39 in the evaporator 34 changes at a substantially constant temperature from the inlet, and shows a temperature distribution that rises near the outlet.

  On the other hand, the evaporator 34 is also a fin tube type heat exchanger like the radiator 32, and the tube (tube) 39 constituting the fin tube has a refrigerant flow meandering, and as a whole, in the direction of the wavy arrow in the figure. Is flowing. And since it controls by the control apparatus 42 as mentioned above, evaporation temperature rises gradually in the direction of a wavy arrow of a figure as a whole. On the other hand, the flow of the outside air serving as a heat source flows in the direction of the solid line arrow in the figure by the fan 35, and heat exchange causes the temperature to gradually decrease. Therefore, the refrigerant flow and the outside air flow are substantially opposite flows. Since the flow becomes temperature efficient from both the air side and the air side, the heat exchange efficiency of the evaporator 34 is improved.

  Thus, since the heat exchange efficiency is improved in both the radiator 32 and the evaporator 34, each refrigerant temperature can be brought close to the load temperature and the heat source temperature, and the discharge pressure of the compressor 31 can be reduced and the suction pressure can be reduced. As a result, the compression power of the compressor 31 is reduced, and the heat pump water heater can be operated with high efficiency.

  On the other hand, the outlet refrigerant of the evaporator 34 whose degree of refrigerant superheat has risen is heat-exchanged with the low-temperature and low-pressure refrigerant in the auxiliary heat exchanger 37 and its temperature is moderately lowered. Therefore, the refrigerant sucked into the compressor 31 is Since the refrigerant temperature has a small degree of normal superheat, the temperature of the compressor 31 does not rise excessively. This tends to increase the discharge pressure of the compressor 31 particularly when the temperature of the air serving as the load of the radiator 32 is high. In such a case, too, the discharge temperature of the compressor 31 is excessively increased. A high-efficiency heat pump operation can be performed without increasing the temperature.

  In this embodiment, the difference between the refrigerant temperature detected by the evaporator outlet temperature sensor provided at the outlet of the evaporator 34 and the evaporation temperature detected by the evaporation temperature sensor 40 provided in the middle of the evaporator 34 pipe. Although the outlet refrigerant superheat degree of the evaporator 34 is calculated from the temperature, it is possible to detect the evaporation pressure of the evaporator 34 to calculate the evaporation temperature, or to substitute the outlet temperature of the main throttle device 33 outlet for the evaporation temperature. These are also included in the present invention.

  In the present embodiment, the auxiliary heat exchanger 37 exchanges heat between the pipe between the main throttle device 33 and the evaporator 34 and the pipe between the evaporator 34 and the compressor 31. The pipe between 33 and the evaporator 34 may be a part of the pipe 39 serving as a two-phase refrigerant in the evaporator 34, and these are also included in the present invention.

  Further, in the present embodiment, the case where air is used on the load side has been described as an example, but the same effect can be obtained even when hot water provided with a hot water supply circuit is used as a load, and these are also included in the present invention. included. Further, in the present embodiment, the case where carbon dioxide gas is used as the refrigerant has been described, but the same effect can be obtained when other single refrigerant or mixed refrigerant is enclosed, and these are also included in the present invention. Here, the auxiliary heat exchanger 37 may have a configuration in which tubes and tubes are brazed, a configuration of a double tube, and the like, which are all included in the present invention.

(Embodiment 2)
FIG. 2 shows a configuration diagram of a heat pump hot-water supply apparatus in the second embodiment of the present invention.

  In FIG. 2, a compressor 51, a radiator 52, a main throttle device 53, and an evaporator 54 are annularly connected in order, and carbon dioxide gas is sealed as a refrigerant to form a refrigerant circulation circuit, and the evaporator 54 blows outside air. A fan 55 is provided.

  Further, a hot water supply circuit in which a hot water tank 56, a circulation pump 57, and a radiator 52 are connected in order is formed, and the high-temperature and high-pressure superheated gas refrigerant discharged from the compressor 51 flows into the radiator 52, where the circulation pump The hot water supplied from 37 is heated.

  Furthermore, the piping between the main expansion device 53 and the evaporator 54 and the piping between the evaporator 54 and the compressor 51 are indirectly heat-exchanged via the auxiliary heat exchanger 58. The radiator 52 is a double-pipe heat exchanger, and the refrigerant pipe has a refrigerant flow in the direction indicated by a solid line arrow and a water flow (in the direction indicated by a wavy arrow in the figure). Further, the evaporator 54 is a fin tube type heat exchanger, and the tube (tube) 59 constituting the fin tube has a refrigerant flow (in the direction of the wavy arrow in the figure) of the outside air (in the figure). The discharge temperature sensor 60 for detecting the discharge gas temperature of the compressor 51 is provided, and the temperature detected by the discharge temperature sensor 60 is set in advance. A control device 61 is provided so as to control the opening degree of the main throttle device 53. Carbon dioxide gas is sealed as a refrigerant.

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

  The refrigerant (carbon dioxide gas) compressed into a supercritical state of high temperature and high pressure by the compressor 51 exchanges heat with water flowing through the hot water supply circuit by the radiator 52. On the other hand, the radiator 52 is a double-pipe heat exchanger, and the temperature of the refrigerant tube gradually decreases as the refrigerant flows in the direction of the solid arrow in the figure. Also, water exchanges heat, and its temperature gradually rises in the direction of the solid arrow in the figure, and the refrigerant flow and the air flow are counterflows, increasing the temperature efficiency from both the refrigerant side and the water side. Since it becomes a flow, the heat exchange efficiency is improved.

  The refrigerant exiting the radiator is decompressed by the main expansion device 53 and then flows into the auxiliary heat exchanger 58. Here, the refrigerant is a low-temperature and low-pressure two-phase refrigerant. Further, the refrigerant flows into the evaporator 54, where it exchanges heat with the outside air blown by the fan 55 to be evaporated into gas. Then, the refrigerant that has exited the evaporator 54 flows into the auxiliary heat exchanger, where it indirectly exchanges heat with the refrigerant that has exited the main expansion device 53 and is then sucked into the compressor 51 again.

Here, the control device 61 controls the opening degree of the main throttle device 53 so that the discharge gas temperature of the compressor 51 detected by the discharge temperature sensor 60 becomes a preset value. That is, if the discharge gas temperature is higher than the set value, the opening of the main throttle device 53 is operated to open, and if the discharge gas temperature is lower than the set value, the main throttle device 53 is operated to close. By doing so, the flow resistance in the main throttle device 33 is varied, the amount of refrigerant circulation to the evaporator 34 is changed, and the degree of refrigerant superheat at the outlet of the evaporator 34 is changed, while being heated by the radiator 52. Hot water is generally required to have a high temperature, in which case a relatively high discharge gas temperature is required. For this reason, the main throttle device 53 is operated in a direction to close the opening so that the discharge gas temperature of the compressor 51 becomes a preset high value.

  When high temperature hot water supply is required, the discharge pressure of the compressor 51 also increases. In such a case, the degree of superheat of the suction gas refrigerant of the compressor 51 cannot be increased so much. In the present invention, even if the degree of superheat of the outlet refrigerant of the evaporator 54 is increased, the auxiliary heat exchanger 58 exchanges heat with the low-temperature and low-pressure two-phase refrigerant. And since the temperature falls moderately, since the suction gas refrigerant | coolant of the compressor 51 becomes a refrigerant | coolant temperature with a small superheat degree, the temperature of the compressor 51 does not rise too much. And since it controls by the control apparatus 61 as mentioned above, the temperature distribution of the pipe | tube 59 of the evaporator 54 becomes high because the superheat degree is taken as an exit, and the average evaporation temperature as a whole is a wavy arrow direction of a figure. It gradually rises.

  On the other hand, the flow of the outside air serving as a heat source flows in the direction of the solid line arrow in the figure by the fan 55 and heat exchange causes the temperature to gradually decrease. Therefore, the refrigerant flow and the outside air flow are substantially counterflows. Since the temperature becomes higher from both the air side and the air side, the heat exchange efficiency of the evaporator 54 is improved. Thus, since the heat exchange efficiency is improved in both the radiator 52 and the evaporator 54, the respective refrigerant temperatures can be brought close to the load temperature and the heat source temperature, and the discharge pressure of the compressor 51 can be reduced and the suction pressure can be reduced. As a result, the compression power of the compressor 51 is reduced, and the heat pump water heater can be operated with high efficiency. This tends to increase the discharge pressure of the compressor 51 especially when the water temperature serving as the load of the radiator 52 is high. In such a case, too, the discharge temperature of the compressor 51 is excessively increased. A highly efficient heat pump operation can be performed without causing it to occur.

  In the present embodiment, the auxiliary heat exchanger 37 exchanges heat between the pipe between the main throttle device 33 and the evaporator 34 and the pipe between the evaporator 34 and the compressor 31. The piping between the evaporators 34 may be a part of the pipe 39 serving as the two-phase refrigerant in the evaporator 34, and these are also included in the present invention.

  In the present embodiment, the case where water is used on the load side has been described as an example. However, similar effects can be obtained even when air is used as a load, and these are also included in the present invention. Further, in the present embodiment, the case where carbon dioxide gas is used as the refrigerant has been described, but the same effect can be obtained when other single refrigerant or mixed refrigerant is enclosed, and these are also included in the present invention. Here, the auxiliary heat exchanger 58 may have a configuration in which a tube and a tube are brazed, a configuration of a double tube, and the like, which are all included in the present invention.

  As described above, the heat pump hot water supply apparatus according to the present invention is used for a heat pump hot water supply apparatus that can generate a high-efficiency and high-temperature hot-water supply water temperature, an air conditioner that obtains high-temperature air, etc. Useful for.

The block diagram of the heat pump hot-water supply apparatus in Embodiment 1 of this invention The block diagram of the heat pump hot-water supply apparatus in Embodiment 2 of this invention Configuration diagram of conventional heat pump water heater

Explanation of symbols

31, 51 Compressor 32, 52 Radiator 33, 53 Main throttle device 34, 54 Evaporator 35, 36, 55 Fan 37, 58 Auxiliary heat exchanger 38, 39, 59 Tube 40 Evaporation temperature sensor 41 Evaporator outlet temperature sensor 42, 61 Control device 56 Hot water storage tank 57 Circulation pump 60 Discharge temperature sensor

Claims (8)

At least a compressor, a radiator, a main throttle device, and an evaporator are sequentially connected to provide a refrigerant circuit, and the refrigerant circuit includes a refrigerant between the main throttle device and the evaporator, and between the evaporator and the compressor. A heat pump hot-water supply device provided with an auxiliary heat exchanger for exchanging heat with the refrigerant. The heat pump hot water supply apparatus according to claim 1, wherein the refrigerant flowing through the evaporator and the heat source side fluid that exchanges heat with the evaporator are configured to flow in a substantially counterflow. The heat pump hot-water supply apparatus according to claim 1 or 2, wherein the refrigerant flowing through the radiator and the load-side fluid that exchanges heat with the radiator are configured to flow in a substantially counterflow. The opening degree of the main throttle device and / or the operating frequency of the compressor are controlled so as to increase the degree of superheat of the outlet refrigerant of the evaporator to a preset value or more. The heat pump hot-water supply apparatus of Claim 1. An evaporation temperature sensor for detecting the evaporation temperature of the evaporator and an evaporator outlet temperature sensor for detecting the outlet refrigerant temperature of the evaporator are provided, and the temperature detected by the evaporator outlet temperature sensor and the temperature detected by the evaporation temperature sensor The heat pump hot-water supply device according to claim 4, wherein the opening degree of the main throttle device and / or the operating frequency of the compressor is controlled so that the temperature difference between the main throttle device and the temperature becomes larger than a preset value. A discharge temperature sensor for detecting the temperature of the refrigerant discharged from the compressor is provided, and the opening of the main throttle device and / or the operating frequency of the compressor so that the temperature of the discharge temperature sensor becomes a preset discharge temperature value. The heat pump hot water supply device according to any one of claims 1 to 3, wherein the heat pump is controlled. The heat pump hot water supply apparatus according to any one of claims 1 to 6, further comprising a hot water supply circuit in which at least a hot water storage tank and a heat radiator are sequentially connected as a heat source side of the radiator. The heat pump hot water supply device according to any one of claims 1 to 7, wherein carbon dioxide gas is used as the refrigerant.

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