JP4124166B2 - Heat pump water heater - Google Patents

Description

  The present invention relates to a hot water storage type heat pump water heater.

  Conventionally, this type of heat pump water heater is shown in FIG. FIG. 5 is a block diagram of a conventional heat pump water heater. In FIG. 5, a refrigerant circulation circuit including 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 (for example, see Patent Document 1).
JP 60-165157 A

  However, in the conventional configuration as described above, a hot water mixed layer is formed at the portion where the hot water in the hot water tank 5 is in contact with water as the boiling operation time elapses, and the layer gradually expands. This occurs due to heat conduction and convection in high temperature hot water and low temperature water. Heat is transferred from the high temperature hot water to the low temperature water, and the temperature of the high temperature hot water decreases at the boundary portion, while the temperature of the low temperature water increases. Accordingly, when the boiling operation is almost completed, the temperature of the water flowing into the hot water supply heat exchanger 2 becomes high, so that the amount of heat dissipated in the hot water supply heat exchanger 2 decreases, and the discharge pressure and discharge of the compressor 1 decrease. As the temperature rises, durability of the compressor 1 such as an increase in the winding temperature of the motor of the compressor 1 becomes a problem.

Therefore, since the operation was stopped in a state where the temperature of the water flowing into the hot water supply heat exchanger 2 was low, the operation was stopped in a state where the lower part of the hot water tank 5 was in a low temperature water state. The hot water capacity could not be used effectively, so the amount of hot water stored was decreasing. In addition, in order to increase the amount of stored hot water, after stopping the heat pump operation, when the amount of stored hot water is increased by the independent operation of the auxiliary heater 19, heating is performed by an electric heater, so that power consumption increases and efficiency decreases. It was.

  The present invention solves the above-mentioned conventional problems, suppresses an increase in the discharge pressure of the compressor, stores no hot water to the lower part of the hot water tank with low power consumption without causing an abnormal temperature rise, and effectively uses the hot water tank capacity. It aims at providing the heat pump hot-water supply apparatus which can be used for.

In order to solve the above-mentioned conventional problems, the heat pump hot water supply apparatus of the present invention is a refrigerant in which at least a compressor, a hot water heat exchanger, a first expansion device, a heat storage device, a second expansion device, and an evaporator are sequentially connected. A hot water supply circuit in which a circuit, at least a hot water storage tank and the heat exchanger for hot water supply are sequentially connected, an incoming water temperature sensor for detecting a temperature of hot water flowing into the hot water heat exchanger, and an outflow of the heat exchanger for hot water supply A hot water temperature sensor for detecting the temperature of hot water to be supplied, a control device for controlling the opening of the first throttling device and the second throttling device, and the first throttling device and the second throttling device. Is capable of controlling the flow rate by varying the throttle opening, and the control device is configured such that the incoming water temperature detected by the incoming water temperature sensor is equal to or higher than a predetermined value and the outgoing hot water temperature detected by the outgoing hot water temperature sensor is higher than a set value. In case Operates the opening degree of the throttle device in the opening direction, the opening degree of the second throttle device characterized in that control to operate in the closing direction, hot water supply is near completion heating operation When the incoming water temperature to the heat exchanger becomes high, the first expansion device is operated in the opening direction, the second expansion device is operated in the closing direction, and the refrigerant pressure flowing into the heat accumulator is increased. This allows the low-temperature heat accumulator to act as a radiator, dissipate heat from the high-temperature and high-pressure refrigerant, store the heat, suppress the rise in discharge pressure of the compressor in the refrigerant circuit and abnormal rise in discharge temperature, Hot water can be stored at the bottom of the hot water tank with low power consumption.

  Further, at the time of starting the compressor, the first expansion device is operated in the closing direction, the second expansion device is operated in the opening direction, and the refrigerant pressure flowing into the regenerator is set to low temperature and low pressure. While absorbing heat and preventing an abnormal drop in compressor suction pressure, the discharge pressure and discharge temperature of the compressor are rapidly increased, and the hot water supply capacity can be improved with low power consumption.

  ADVANTAGE OF THE INVENTION According to this invention, the heat pump hot water supply apparatus which suppresses the discharge pressure rise of a compressor, does not have abnormal temperature rise, can store hot water to the lower part of a hot water tank with low power consumption, and can utilize the capacity | capacitance of a hot water tank effectively. Can provide.

A first invention includes a refrigerant circuit in which at least a compressor, a hot water supply heat exchanger, a first expansion device, a heat storage device, a second expansion device, and an evaporator are sequentially connected, at least a hot water storage tank, and the hot water supply heat exchange. A hot water supply circuit in which the heaters are sequentially connected, an incoming water temperature sensor that detects the temperature of hot water flowing into the hot water heat exchanger, and a hot water temperature sensor that detects the temperature of hot water flowing out of the hot water heat exchanger, A control device for controlling the opening of the first throttling device and the second throttling device, and the first throttling device and the second throttling device can control the flow rate by varying the throttling opening. The controller opens the first throttling device when the incoming water temperature detected by the incoming water temperature sensor is equal to or higher than a predetermined value and the outgoing hot water temperature detected by the outgoing hot water temperature sensor is higher than a set value. Is moved in the opening direction and the second aperture is The opening of the device intended to control so as to operate in the closing direction, even if the incoming water temperature is higher so close operation completion boiling, it is possible to apply a heat accumulator as a radiator, a refrigerant circuit The hot water supply can be easily heated to a high temperature while reducing the discharge pressure and discharge temperature of the compressor, and the heat pump can be operated safely and efficiently. Moreover, hot water can be stored up to the bottom of the hot water tank, and the capacity of the hot water tank can be used effectively.

The first throttle device and the second throttle device, throttle opening degree is variable, characterized in that can control the flow rate, the discharge pressure of the compressor of the refrigerant circuit without increasing the number of parts and the discharge temperature Can be reduced.

Further, when the refrigerant circuit is started up or when the incoming water temperature is low, a low-temperature and low-pressure refrigerant flows through the heat accumulator, so that a large amount of heat can be taken and the heat pump can be operated with high efficiency.

In addition, by making the refrigerant pressure flowing into the heat accumulator high, the heat accumulator can act as a radiator and the discharge pressure of the compressor of the refrigerant circuit can be reduced, and the heat pump can be operated safely and efficiently. Can do.

The second invention, only setting the outside air temperature sensor over which detects the outside air temperature, the control device includes a water inlet temperature detected by the incoming water temperature sensor, a hot water temperature detected in a water temperature sensor output, detected by the outside air temperature sensor Based on the outside air temperature, the opening degree of the first expansion device is controlled to operate in the opening direction, and the opening amount of the second expansion device is controlled to operate in the closing direction. By making the refrigerant pressure flowing into the refrigerant high, the heat accumulator can act as a radiator, the discharge pressure of the compressor of the refrigerant circuit can be reduced, and the heat pump can be operated with higher efficiency.

The third invention is provided with a bypass circuit via a second two-way valve that bypasses the first throttle device of the refrigerant circuit, and reduces the discharge pressure of the compressor of the refrigerant circuit at a low cost, The hot water can be heated to a higher temperature safely and efficiently, and the amount of stored hot water can be increased.

A fourth invention is the control apparatus, when the incoming water temperature detected by the incoming water temperature sensor is equal to or higher than a set value,-out the second two-way valve of the bypass circuit open, the opening degree of the second throttle device It is characterized in that it is controlled to operate in the closing direction. When the incoming water temperature is low, the heat accumulator acts as an evaporator, so it can take a large amount of heat absorption, and the heat pump can be increased at low cost. You can drive with efficiency.

A fifth invention is the control apparatus, incoming water temperature detected by the incoming water temperature sensor set value or more, One or, if hot water temperature detected by the output water temperature sensor is equal to or higher than a set value, the bypass circuit the second The two-way valve is opened and the opening of the second expansion device is controlled so as to operate in the closing direction. The refrigerant is discharged from the heat accumulator by increasing the refrigerant pressure flowing into the heat accumulator. The discharge pressure of the compressor of the refrigerant circuit can be reduced, and the heat pump can be safely and efficiently operated at low cost.

6th invention provides the outside temperature sensor which detects outside temperature, and a control apparatus is the outside water temperature detected with the incoming water temperature detected with the incoming water temperature sensor, the outgoing hot water temperature detected with the outgoing water temperature sensor, and the outdoor air temperature sensor. On the basis of this, the second two-way valve of the bypass circuit is opened and the opening of the second expansion device is controlled to operate in the closing direction, and the refrigerant pressure flowing into the regenerator is increased. By doing so, the heat accumulator can act as a radiator, the discharge pressure of the compressor of the refrigerant circuit can be reduced, and the heat pump can be safely and efficiently operated at low cost.

The seventh invention is characterized in that a hot gas bypass circuit is provided between the first expansion device and the heat accumulator so as to allow the refrigerant discharged from the compressor to flow in. During the defrosting operation, the hot gas bypass circuit is provided. Therefore, while absorbing the heat stored in the heat storage agent of the heat accumulator, the high-temperature and high-pressure refrigerant can be flowed into the evaporator, and the frosting of the evaporator can be melted quickly, reducing the defrosting operation time and improving efficiency. Driving is possible.

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 water heater in the first embodiment of the present invention.

  In FIG. 1, a compressor 31, a hot water supply heat exchanger 32, a first expansion device 33, a heat storage device 34, a second expansion device 35, and an evaporator 36 are sequentially connected in an annular shape, and carbon dioxide gas is sealed as a refrigerant. Thus, the refrigerant circuit 40 is formed, and the evaporator 36 is provided with a fan 39 for blowing outside air. Further, a hot water supply circuit 43 in which a hot water tank 41, a circulation pump 42, and a hot water supply heat exchanger 32 are connected in order is formed, and the high-temperature and high-pressure superheated gas refrigerant discharged from the compressor 31 is supplied to the hot water supply heat exchanger 32. The hot water supplied from the circulation pump 42 is heated here. Also, an incoming water temperature sensor 51 for detecting the incoming water temperature flowing into the hot water supply heat exchanger 32, a hot water temperature sensor 52 for detecting the outgoing water temperature flowing out from the hot water heat exchanger 32, and an outside air temperature sensor 53 for detecting the outside air temperature are provided. A control device 54 is provided for controlling the opening and closing of the first throttling device 33 and the second throttling device 35 in comparison with a preset temperature.

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

  During normal operation, the opening of the second expansion device 35 is fully opened, low temperature and low pressure refrigerant flows through the heat accumulator 34, and the heat storage agent is kept at a low temperature. At this time, the refrigerant (carbon dioxide gas) compressed to a supercritical state of high temperature and high pressure by the compressor 31 exchanges heat with water flowing through the hot water supply circuit 43 by the hot water supply heat exchanger 32, and becomes a medium temperature and high pressure refrigerant. After the pressure is reduced by the first expansion device 33, the refrigerant flows into the heat accumulator 34 and the evaporator 36, and the evaporator 36 exchanges heat with the outside air blown by the fan 39 to evaporate and return to the compressor 31. On the other hand, the hot water sent by the circulation pump 42 is heated by the hot water heat exchanger 32, and the generated hot water flows into the upper part of the hot water storage tank 41 and is gradually stored from above. On the other hand, as the boiling operation time elapses, a hot water mixed layer is formed at the portion where the hot water in the hot water storage tank 41 comes into contact with water, and the layer expands to the lower part of the hot water storage tank 41. The water temperature flowing into the hot water supply heat exchanger 32 from the lower part 41 through the circulation pump 42 becomes higher.

  In this case, in the hot water supply heat exchanger 32, the refrigerant only dissipates heat up to the inflowing water temperature, so the density of the refrigerant at the outlet of the hot water supply heat exchanger 32 is low and the high pressure increases. At this time, when the incoming water temperature detected by the incoming water temperature sensor 51 rises above the temperature preset in the control device 54, the first throttle device 33 is operated in the opening direction, and the second throttle device 35 is closed. To work. In this way, by making the refrigerant pressure flowing into the heat accumulator 34 high, the heat accumulator 34 acts as a radiator, and the high-temperature and high-pressure refrigerant exchanges heat with the low-temperature heat storage agent to become a medium-temperature and high-pressure refrigerant, After being reduced in pressure by the second expansion device 35 and becoming a low-temperature and low-pressure refrigerant, it flows into the evaporator 36, exchanges heat with the outside air, evaporates, and returns to the compressor 31.

At this time, since the heat accumulator 34 acts as a radiator, among the refrigerant sealed in the refrigerant circuit 40, the place where the high-pressure refrigerant can exist becomes the hot water supply heat exchanger 32 and the heat accumulator 34, and the volume increases. Since the refrigerant is dissipated by the heat accumulator 34, a high-density refrigerant exists in the heat accumulator 34. Moreover, a heat storage agent becomes high temperature and high temperature heat is stored. When the incoming water temperature detected by the incoming water temperature sensor 51 rises above the temperature preset in the control device 54, it is determined that hot water has been stored up to the lower part of the hot water tank 41, and the operation of the compressor 31 is stopped. .

  As a result, the discharge pressure of the compressor 31 of the refrigerant circuit 40 can be reduced, and the heat pump water heater can be operated safely and with high efficiency. Moreover, hot water can be stored up to the lower part of the hot water tank 41, and the capacity of the hot water tank 41 can be effectively used.

  Further, when the operation of the refrigerant circuit 40 is stopped, since the high-temperature heat is stored in the heat storage agent, the hot water in the hot water storage tank 41 is reduced by the hot water supply, and the operation of the refrigerant circuit 40 is started. The device 33 is operated in the closing direction, the second expansion device 35 is operated in the opening direction, and the refrigerant pressure flowing into the heat accumulator 34 is set to a low temperature and a low pressure. The refrigerant absorbs heat and prevents an abnormal decrease in the suction pressure of the compressor 31 and rapidly increases the discharge pressure and discharge temperature of the compressor 31 to improve the hot water supply capacity with low power consumption.

  In addition, when the hot water temperature is high, it is necessary to increase the discharge temperature of the compressor 31 of the refrigerant circuit 40. For this purpose, it is also necessary to increase the discharge pressure of the compressor 31. Therefore, when the incoming water temperature rises, the discharge pressure of the compressor 31 increases as the hot water temperature increases.

  Accordingly, when the incoming water temperature detected by the incoming water temperature sensor 51 and the outgoing hot water temperature detected by the outgoing hot water temperature sensor 52 rise above the temperature preset in the control device 54, the first throttle device 33 is operated in the opening direction. Then, the second expansion device 35 is operated in the closing direction, the refrigerant pressure flowing into the heat accumulator 34 is set to a high pressure, and the heat accumulator 34 is operated as a radiator, whereby the discharge pressure of the compressor 31 of the refrigerant circuit 40 is increased. The heat pump water heater can be operated more safely and efficiently.

  Further, when the outside air temperature is high, the evaporation pressure increases. The higher the evaporation pressure, the smaller the specific volume of the refrigerant sucked in the compressor 31, the refrigerant circulation amount increases, and the hot water supply capacity increases. Therefore, the discharge pressure of the compressor 31 increases as the outside air temperature increases.

  Thus, the discharge pressure of the compressor 31 tends to increase as the hot water temperature and the outside air temperature are higher and the incoming water temperature is higher. Therefore, the first throttling device 33 is operated in the opening direction by the incoming water temperature detected by the incoming water temperature sensor 51, the outgoing hot water temperature detected by the outgoing hot water temperature sensor 52, and the outside air temperature detected by the outdoor air temperature sensor 53, and the second The discharge pressure of the compressor 31 of the refrigerant circuit 40 can be reduced by operating the expansion device 35 in the closing direction, setting the refrigerant pressure flowing into the heat accumulator 34 to a high pressure, and causing the heat accumulator 34 to act as a radiator. The heat pump water heater can be operated more safely and efficiently.

  Further, when the evaporator 36 is frosted by operation at a low outside air temperature, the frost may be formed if the outside air temperature detected by the outside air temperature sensor 53 is lower than the temperature preset in the control device 54. It is determined that there is, and the first diaphragm device 33 is operated in the opening direction, and the second diaphragm device 35 is operated in the closing direction. By doing so, the refrigerant pressure flowing into the heat accumulator 34 is set to a high pressure, so that the high-temperature and high-pressure refrigerant exchanges heat with the low-temperature heat accumulator and stores the heat in the heat accumulator 34.

Thereafter, when the temperature of the evaporator 36 is lowered and the defrosting operation is performed, the second expansion device 35 is operated in the opening direction, a high-temperature and high-pressure refrigerant is caused to flow into the evaporator 36, and the evaporator 36 forms frost. Melt. At this time, since heat can be absorbed from the heat accumulator 34, the frost formation of the evaporator 36 can be quickly melted, the defrosting operation time can be shortened, and an efficient operation can be performed.

  In addition, as shown in FIG. 2, the hot gas bypass circuit 38 through the two-way valve 37 which makes the discharge refrigerant | coolant of the compressor 31 flow in between the 1st expansion device 33 and the thermal accumulator 34 is provided, and defrost operation is carried out. At this time, the two-way valve 37 is opened, and the heat stored in the heat storage agent of the heat storage device 34 is absorbed, and a high-temperature and high-pressure refrigerant is introduced into the evaporator 36 so that the frost formation on the evaporator 36 is melted. The frosting of the evaporator 36 can be quickly melted, the defrosting operation time can be shortened, and the efficient operation can be performed.

(Embodiment 2)
FIG. 3 shows a configuration diagram of a heat pump water heater in the second embodiment of the present invention.

  In FIG. 3, the same elements as those in FIG. Here, the difference from FIG. 1 is that a bypass circuit 45 via a second two-way valve 44 and a control device 54 for controlling the opening and closing of the second two-way valve 44 are provided in parallel with the first throttling device 33. That is.

  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 water flowing through the hot water supply circuit 43 by the hot water supply heat exchanger 32, and becomes a medium temperature and high pressure refrigerant. Since the two-way valve 44 is closed, it flows into the first throttling device 33 and becomes a low-temperature and low-pressure refrigerant that has been reduced in pressure, flows into the evaporator 36 through the heat accumulator 34, and is blown by the fan 39 by the evaporator 36. The heat is exchanged with the outside air thus converted into evaporative gas, and the compressor 31 is returned. On the other hand, the hot water sent by the circulation pump 42 is heated by the hot water heat exchanger 32, and the generated hot water flows into the upper part of the hot water storage tank 41 and is gradually stored from above. At this time, the heat storage agent of the heat storage device 34 becomes a low temperature.

  On the other hand, as the boiling operation time elapses, a hot water mixed layer is formed at a portion where the hot water in the hot water storage tank 41 comes into contact with water, and the layer expands to the lower part of the hot water storage tank 41. The temperature of water flowing into the hot water supply heat exchanger 32 from the lower part through the circulation pump 42 becomes higher.

  In this case, when the incoming water temperature detected by the incoming water temperature sensor 51 rises above the temperature preset in the control device 54, the second two-way valve 44 of the bypass circuit 45 is opened, and the second throttle device The opening of 35 is operated in the closing direction. In this way, by making the refrigerant pressure flowing into the heat accumulator 34 high, the heat accumulator 34 acts as a radiator, and the high-temperature and high-pressure refrigerant exchanges heat with the low-temperature heat storage agent to become a medium-temperature and high-pressure refrigerant, After being reduced in pressure by the second expansion device 35 and becoming a low-temperature and low-pressure refrigerant, it flows into the evaporator 36, exchanges heat with the outside air, evaporates, and returns to the compressor 31.

  At this time, since the heat accumulator 34 acts as a radiator, among the refrigerant sealed in the refrigerant circuit 40, the place where the high-pressure refrigerant can exist becomes the hot water supply heat exchanger 32 and the heat accumulator 34, and the volume increases. Since the refrigerant is dissipated by the heat accumulator 34, a high-density refrigerant exists in the heat accumulator 34. Moreover, a heat storage agent becomes high temperature and high temperature heat is stored. When the incoming water temperature detected by the incoming water temperature sensor 51 rises above the temperature preset in the control device 54, it is determined that hot water has been stored up to the lower part of the hot water tank 41, and the operation of the compressor 31 is stopped. .

As a result, the discharge pressure of the compressor 31 of the refrigerant circuit 40 can be reduced, and the heat pump water heater can be operated safely and with high efficiency. Moreover, hot water can be stored up to the lower part of the hot water tank 41, and the capacity of the hot water tank 41 can be effectively used.

  Further, when the operation of the refrigerant circuit 40 is stopped, since the high-temperature heat is stored in the heat storage agent, the hot water in the hot water storage tank 41 is reduced by the hot water supply, and when the operation of the refrigerant circuit 40 is started, The second two-way valve 44 is closed, the first throttling device 33 is operated in the closing direction, the second throttling device 35 is operated in the opening direction, and the refrigerant pressure flowing into the heat accumulator 34 is reduced to low temperature and low pressure. As a result, the refrigerant absorbs the heat of the high-temperature heat storage agent of the heat accumulator 34 to prevent an abnormal decrease in the suction pressure of the compressor 31, and the discharge pressure and discharge temperature of the compressor 31 are rapidly increased to reduce consumption. Hot water supply capacity can be improved by the amount of electric power.

  Further, when the evaporator 36 is frosted by operation at a low outside air temperature, the frost may be formed if the outside air temperature detected by the outside air temperature sensor 53 is lower than the temperature preset in the control device 54. When it is determined that there is, the second two-way valve 44 of the bypass circuit 45 is opened, the first throttling device 33 is bypassed, and the second throttling device 35 is operated in the closing direction. By doing so, the refrigerant pressure flowing into the heat accumulator 34 is set to a high pressure, so that the high-temperature and high-pressure refrigerant exchanges heat with the low-temperature heat accumulator and stores the heat in the heat accumulator 34. Thereafter, when the temperature of the evaporator 36 is lowered and the defrosting operation is performed, the second expansion device 35 is operated in the opening direction, a high-temperature and high-pressure refrigerant is caused to flow into the evaporator 36, and the frosting of the evaporator 36 is performed. Melt. At this time, since heat can be absorbed from the heat accumulator 34, the frost formation of the evaporator 36 can be quickly melted, the defrosting operation time can be shortened, and an efficient operation can be performed.

  In addition, as shown in FIG. 4, the hot gas bypass circuit 38 through the two-way valve 37 which makes the discharge refrigerant | coolant of the compressor 31 flow in between the 1st expansion device 33 and the thermal accumulator 34 is provided, and defrost operation is carried out. At this time, the two-way valve 37 is opened, and the heat stored in the heat storage agent of the heat storage device 34 is absorbed, and a high-temperature and high-pressure refrigerant is introduced into the evaporator 36 so that the frost formation on the evaporator 36 is melted. The frosting of the evaporator 36 can be quickly melted, the defrosting operation time can be shortened, and the efficient operation can be performed.

  As described above, the heat pump hot water supply apparatus according to the present invention can easily heat the hot water supply to a high temperature while reducing the discharge pressure and discharge temperature of the compressor of the refrigerant circuit. It is useful for applications such as a heat pump water heater to be obtained and an air conditioner to obtain high temperature air.

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

Explanation of symbols

DESCRIPTION OF SYMBOLS 31 Compressor 32 Hot water supply heat exchanger 33 1st expansion device 34 Heat storage device 35 2nd expansion device 36 Evaporator 37 Two-way valve 38 Hot gas bypass circuit 39 Fan 40 Refrigerant circuit 41 Hot water tank 42 Circulation pump 43 Hot water supply circuit 44 Second second two-way valve 45 Bypass circuit 51 Incoming water temperature sensor 52 Hot water temperature sensor 53 Outside air temperature sensor 54 Control device

Claims (8)

A refrigerant circuit in which at least a compressor, a hot water heat exchanger, a first expansion device, a heat storage device, a second expansion device, and an evaporator are sequentially connected, and at least a hot water storage tank and the hot water supply heat exchanger are sequentially connected. A circuit , a water temperature sensor that detects the temperature of hot water flowing into the hot water heat exchanger, a hot water temperature sensor that detects the temperature of hot water flowing out of the hot water heat exchanger, and the first throttle Apparatus, a control device for controlling the opening of the second throttle device, the first throttle device and the second throttle device can control the flow rate by varying the throttle opening, the control device, When the incoming water temperature detected by the incoming water temperature sensor is equal to or higher than a predetermined value and the outgoing hot water temperature detected by the outgoing hot water temperature sensor is higher than a set value, the opening of the first throttling device is operated in the opening direction. , The opening of the second throttle device The heat pump water heater and controls to operate the direction. Only set the outside air temperature sensor over which detects the outside air temperature, the control device includes a water inlet temperature detected by the incoming water temperature sensor, a hot water temperature detected by the water temperature sensor output, based on the outside air temperature detected by the outside air temperature sensor The heat pump hot water supply apparatus according to claim 1, wherein the opening degree of the first throttling device is controlled to operate in the opening direction, and the opening degree of the second throttling device is controlled to operate in the closing direction. The heat pump hot-water supply apparatus according to claim 1 or 2 , further comprising a bypass circuit through a two-way valve that bypasses the first throttling device of the refrigerant circuit. Control apparatus, when the incoming water temperature detected by the incoming water temperature sensor is equal to or higher than a set value,-out two-way valve of the bypass circuit open, the opening degree of the second throttle device is controlled so as to operate in the closing direction The heat pump hot water supply apparatus according to claim 3 . Controller, the incoming water temperature detected by the incoming water temperature sensor set value or more, One or, if hot water temperature detected by the output water temperature sensor is equal to or higher than a set value, open the second two-way valve of the bypass circuit, the 4. The heat pump hot water supply apparatus according to claim 3 , wherein the opening degree of the expansion device of 2 is controlled to operate in the closing direction. An outside air temperature sensor for detecting the outside air temperature is provided, and the control device is configured to control the bypass circuit based on the incoming water temperature detected by the incoming water temperature sensor, the outgoing hot water temperature detected by the outgoing hot water temperature sensor, and the outdoor air temperature detected by the outdoor air temperature sensor. The heat pump hot water supply apparatus according to claim 3 , wherein the second two-way valve is opened and the opening of the second expansion device is controlled to operate in the closing direction. The heat pump hot water supply apparatus according to any one of claims 1 to 6 , wherein a hot gas bypass circuit for allowing a refrigerant discharged from the compressor to flow in is provided between the first expansion device and the heat accumulator. 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.

Images