JP5478403B2 - Heat pump water heater - Google Patents

Description

  The present invention relates to a heat pump water heater.

  As a conventional heat pump hot water supply apparatus, “the opening degree of the pressure reducing means (3), the rotation speed of the compressor (1), the flow rate of the heated medium, and the cooling medium based on the detection result of the high pressure detecting means (9)” There is provided a control means (12) for controlling at least one of the flow rates to a high pressure side refrigerant pressure range in which the coefficient of performance of the refrigeration cycle (R) is near the maximum (see, for example, Patent Document 1). ).

  Further, as a conventional heat pump hot water supply apparatus, “supercritical that controls the opening degree of the electric expansion valve (4) so that the high pressure becomes a target pressure determined based on the refrigerant temperature on the outlet side of the radiator (2)”. "In the refrigeration cycle", "For a predetermined time after the compressor (1) is started, the starting target pressure (Po2) is set as the target pressure of the high pressure to control the opening of the electric expansion valve (4); On the other hand, after a predetermined time has elapsed after the compressor (1) is started, the steady-state target pressure (Po1) is set as the target pressure of the high pressure to control the opening of the electric expansion valve (4). " There are some (see, for example, Patent Document 2).

JP 2004-239482 A (page 5) JP 2008-82637 A (3rd page, 7th page, FIG. 4)

  In the techniques described in Patent Documents 1 and 2, the time from when the heat pump water heater is started until the refrigeration cycle capacity is stabilized, that is, the rise time is not considered, and the rise time may take a long time. It was. In particular, in Patent Document 2, since the starting target pressure is set to a value lower than the steady-state target pressure during a transition immediately after the start of the refrigeration cycle, the rise time of the refrigeration cycle may be long.

  The present invention has been made to solve the above-described problems, and provides a heat pump hot water supply apparatus capable of speeding up the start of the refrigeration cycle.

The heat pump hot water supply apparatus according to the present invention includes a refrigerant circuit in which a compressor, a refrigerant-water heat exchanger, a decompression device, and an evaporator are sequentially connected, and a high-pressure detection unit that detects a refrigerant pressure discharged from the compressor A heat pump unit, a tank unit having a hot water tank for storing hot water heated by the refrigerant-water heat exchanger, and a hot water circulation device connected between the refrigerant-water heat exchanger and the hot water tank And at least one of the rotation speed of the compressor and the throttle amount of the pressure reducing device so that the discharged refrigerant pressure detected by the high pressure detecting means becomes a preset target pressure. a heat pump unit control means for controlling, and a discharge temperature detection means for detecting the discharge refrigerant temperature discharged from the compressor, startup operation and cause Two types of target pressure at the time of steady operation preset performed subsequent to the operation, the startup operation is obtained by setting high the target pressure than during the steady operation, the heat pump unit control means, said When the discharge refrigerant pressure has not reached the target pressure during start-up operation, the number of revolutions of the compressor is increased when the discharge refrigerant temperature has reached a predetermined upper limit value, and the discharge refrigerant temperature becomes the predetermined upper limit value. When not reached, control is performed to increase the throttle amount of the decompression device .

  Since the heat pump hot water supply apparatus of the present invention sets the target pressure at the time of startup higher than the target pressure at the time of steady operation, the start-up of the capacity of the refrigeration cycle can be speeded up.

It is a system configuration figure of the heat pump hot-water supply apparatus concerning an embodiment. It is a figure which shows the target discharge pressure of the compressor which concerns on embodiment. It is a figure explaining the adjustment method of the target pressure which concerns on embodiment. It is a figure explaining the other adjustment method of the target pressure which concerns on embodiment. It is a flowchart which shows an example of the switching operation | movement of the target pressure which concerns on embodiment. It is a flowchart which shows the other example of the switching operation | movement of the target pressure which concerns on embodiment. It is a flowchart which shows the other example of the switching operation | movement of the target pressure which concerns on embodiment. It is a figure which shows the relationship between the target boiling temperature which concerns on embodiment, and the discharge refrigerant | coolant temperature of a compressor. It is a flowchart explaining the rotation speed control of the compressor in the boiling operation which concerns on embodiment, and the amount-of-throttling control of a decompression device.

Embodiment.
(System configuration of heat pump water heater)
FIG. 1 is a system configuration diagram of a heat pump hot water supply apparatus according to an embodiment of the present invention. The heat pump hot water supply apparatus includes a heat pump unit 100, a tank unit 200, and an operation unit 11 for a user to set a hot water supply temperature, an amount of water, and the like.

  The heat pump unit 100 includes a refrigerant circulation circuit in which the compressor 1, the refrigerant-water heat exchanger 2, the decompression device 3, and the evaporator 4 are connected in a ring shape by a refrigerant pipe 15. A pressure detection device 5 that detects the discharge pressure of the compressor 1 is provided on the outlet side of the compressor 1. The evaporator 4 is provided with a fan 7 driven by a fan motor 6.

The tank unit 200 includes a hot water tank 14 that stores hot water heated by the refrigerant-water heat exchanger 2, and a hot water (including water) circulation device that is disposed between the refrigerant-water heat exchanger 2 and the hot water tank 14. 10 are connected by a hot water circulation pipe 16 to constitute a hot water circulation circuit.
Moreover, the tank unit control part 12 which controls the rotation speed of the hot water circulation apparatus 10 based on the signal from the operation part 11 is provided.

  On the water supply side to the refrigerant-water heat exchanger 2, that is, on the side where water flows from the hot water circulation pipe 16 into the refrigerant-water heat exchanger 2, water supply temperature detection means 9 for detecting the temperature of the flowing water is provided. Yes. A boiling temperature detecting means 8 for detecting the temperature of the flowing warm water (hereinafter referred to as the boiling temperature) is provided on the side where the warm water flows out of the refrigerant-water heat exchanger 2. In the vicinity of the discharge side pipe of the compressor 1, a discharge temperature detecting means 18 for detecting the refrigerant temperature discharged from the compressor 1 is provided. In addition, an outside air temperature detecting means 17 for detecting the outside air temperature around the heat pump unit 100 is provided at or near the outer periphery of the heat pump unit 100.

  Signals of detection results from the pressure detection device 5, the feed water temperature detection means 9, the boiling temperature detection means 8, the outside air temperature detection means 17, and the discharge temperature detection means 18 are transmitted to the heat pump unit control unit 13. A signal from the operation unit 11 is also transmitted to the heat pump unit control unit 13 via the tank unit control unit 12. The heat pump unit control unit 13 has a function of receiving the signal, and controls the rotational speed of the compressor 1, the amount of throttle of the decompression device 3, and the rotational speed of the fan motor 6. The tank unit control part 12 and the heat pump unit control part 13 are comprised by CPU and a microcomputer and the program memorize | stored in them, for example.

(Overview of boiling operation)
Next, the boiling operation operation of the heat pump hot water supply apparatus according to the present embodiment will be described. When a boiling operation instruction from the operation unit 11 based on an input from the user or a boiling operation instruction from the tank unit 200 is received, the heat pump unit 100 performs the boiling operation. Specifically, the heat pump unit control unit 13 performs the rotational speed control of the compressor 1, the throttle amount control of the decompression device 3, and the rotational speed control of the fan motor 6. Furthermore, the tank unit control unit 12 sets the rotation speed of the hot water circulation device 10 based on the signal from the heat pump unit control unit 13 so that the boiling temperature detected by the boiling temperature detection means 8 becomes the target boiling temperature. Control. Here, it is assumed that the target boiling temperature is set by an input from the user to the operation unit 11.

  By such control, the high-pressure / high-temperature refrigerant discharged from the compressor 1 dissipates heat in the refrigerant-water heat exchanger 2 to become a high-pressure / low-temperature refrigerant. And the refrigerant | coolant which came out of the refrigerant | coolant-water heat exchanger 2 is pressure-reduced by the decompression device 3, and becomes a low voltage | pressure low temperature refrigerant | coolant. The refrigerant that has passed through the decompression device 3 circulates back to the compressor 1 after exchanging heat with air in the evaporator 4. On the other hand, the water in the lower part of the hot water tank 14 flows into the refrigerant-water heat exchanger 2 by the hot water circulation device 10, where it is heated by heat exchange with the refrigerant in the refrigerant circulation circuit, and passes through the hot water circulation pipe 16. Circulate to enter the hot water tank 14. In this way, the heated warm water is stored in the warm water tank 14.

Next, a boiling operation (hereinafter referred to as start-up operation) immediately after the start of boiling of the heat pump water heater and a boiling operation (hereinafter referred to as steady operation) performed after the start-up operation will be further described.
When the heat pump hot water supply apparatus according to the present embodiment receives an instruction to start a boiling operation, it first performs a startup operation. When the transition condition from the startup operation to the steady operation is satisfied, the operation shifts to the steady operation.

(Target discharge pressure for start-up operation and steady operation)
FIG. 2 is a diagram showing a target discharge pressure (hereinafter referred to as a target pressure) of the compressor 1 in the start-up operation and the steady operation. As shown in FIG. 2, the heat pump water heater of the present embodiment sets different target pressures for the start-up operation and the steady operation. Then, the target pressure during start-up operation (hereinafter referred to as start-up target pressure P1) is set higher than the target pressure during steady-state operation (hereinafter referred to as steady-state target pressure P2).

  Thus, by setting the startup target pressure P1 higher than the steady-state target pressure P2, it is possible to speed up the rise in the capacity of the refrigeration cycle during startup operation. Therefore, it is possible to shorten the time until the capacity of the refrigeration cycle is stabilized after the start-up operation is started.

(Target pressure adjustment method)
Furthermore, in this embodiment, the startup target pressure P1 shown in FIG. 2 is adjusted according to the target boiling temperature and the outside air temperature. Hereinafter, a method for adjusting the target pressure will be described with reference to FIGS. 3 and 4.

FIG. 3 is a diagram illustrating a method for adjusting the target pressure. The heat pump unit control unit 13 adjusts the target pressure based on the boiling temperature detected by the boiling temperature detection means 8. Specifically, the target pressure is adjusted higher as the target boiling temperature becomes higher.
Since the refrigeration cycle takes a longer time to start up as the target boiling temperature increases, the refrigeration cycle needs to start up by setting the target pressure P1 at startup higher as the target boiling temperature increases as shown in FIG. Time can be further reduced.

FIG. 4 is a diagram illustrating another method for adjusting the target pressure. The heat pump unit control unit 13 adjusts the target pressure based on the outside air temperature detected by the outside air temperature detecting means 17. Specifically, the target pressure is adjusted lower as the outside air temperature becomes higher, and conversely, the target pressure is adjusted higher as the outside air temperature becomes lower.
In the heat pump cycle, the time required for the start-up becomes longer as the outside air temperature becomes lower. Therefore, when the outside air temperature is low as shown in FIG. It can be shortened. Further, since the refrigerant pressure is likely to rise when the outside air temperature is high, the load on the compressor 1 can be reduced by setting the target pressure P1 at the start-up low when the outside air temperature is high, and the compression is performed. The reliability of the machine 1 can be increased.

3 and 4 each show an example in which the startup target pressure P1 is adjusted based on the target boiling temperature and the outside air temperature. However, the startup target is based on both the target boiling temperature and the outside air temperature. The pressure P1 may be adjusted. By doing in this way, while being able to shorten the rise time of a heat pump cycle, the load to the compressor 1 can also be reduced.
Similarly, the steady-state target pressure P2 may be adjusted based on the target boiling temperature and / or the outside air temperature.

(Conditions for switching from startup target pressure P1 to steady-state target pressure P2)
Next, three embodiments of the conditions for switching from the startup target pressure P1 to the steady-state target pressure P2, that is, the transition conditions when shifting from the startup operation to the steady operation will be described with reference to FIGS. .

FIG. 5 is a diagram illustrating an example of a switching condition from the startup target pressure P1 to the steady-state target pressure P2.
When the start of boiling is instructed and the startup operation is started, the heat pump unit controller 13 sets the startup target pressure P1 as the target pressure of the compressor 1 and performs the boiling operation (S1). Next, it is determined whether or not the predetermined time T1 has elapsed from the start of the start-up operation. If the predetermined time T1 has elapsed (S2: Yes), the target pressure of the compressor 1 is changed to the steady-state target pressure P2 ( S3). When the predetermined time T1 has not elapsed since the start of the start operation (S2: No), the boiling operation is performed with the start target pressure P1 being maintained (S1). The predetermined time T1 is, for example, 10 minutes to 20 minutes. Although this predetermined time T1 is influenced by environmental factors such as the outside air temperature at the start of operation and whether it is a cold start or a hot start, it is a time until the discharged refrigerant temperature and the boiling temperature are substantially stabilized, such as a test in advance. To determine.

  That is, when a predetermined time T1 has elapsed since the start-up operation was started, the target pressure of the compressor 1 is changed from the start-time target pressure P1 to the steady-state target pressure P2. As described above, by switching the target pressure depending on whether or not the predetermined time T1 has elapsed, it is possible to limit the operation time at the startup target pressure P1, which is a high target pressure. For this reason, the load to the compressor 1 due to the high target pressure can be suppressed, and the reliability of the compressor 1 can be improved.

FIG. 6 is a diagram illustrating another example of the switching condition from the startup target pressure P1 to the steady-state target pressure P2. In FIG. 6, the difference from FIG. 5 will be mainly described, and the same reference numerals are given to the same processes as in FIG. 5.
In step S21 of FIG. 6, the heat pump unit controller 13 determines whether or not the boiling temperature detected by the boiling temperature detection means 8 has reached the target boiling temperature Q, and if not (S21: No) ), The boiling operation is performed with the target pressure P1 at the start. If the boiling temperature has reached the target boiling temperature Q (S21: Yes), it is determined whether or not a predetermined time T2 has elapsed since the boiling temperature reached the target boiling temperature Q (S22). If the predetermined time T2 has elapsed (S22: Yes), the target pressure of the compressor 1 is changed to the steady-state target pressure P2 (S3). When the predetermined time T2 has not elapsed (S22: No), the boiling operation is performed with the start time target pressure P1 being maintained.

  That is, when the boiling temperature reaches the target boiling temperature Q and the predetermined time T2 has passed in that state, it is determined that the boiling temperature has become stable, and the target pressure of the compressor 1 is set to the startup target. The pressure P1 is changed to the steady target pressure P2. Thus, the stability of the boiling temperature after changing the target pressure can be increased by changing the target pressure to the steady-state target pressure P2 after the boiling temperature reaches the target value. Further, by waiting for the elapse of the predetermined time T2 after the boiling temperature reaches the target value, the detection error of the boiling temperature by the boiling temperature detection means 8 can be absorbed, and the target pressure can be accurately changed. Can do.

FIG. 7 is a diagram illustrating another example of the switching condition from the startup target pressure P1 to the steady-state target pressure P2. In FIG. 7, the difference from FIG. 5 will be mainly described, and the same reference numerals are given to the processes similar to those in FIG. 5.
In step S31 of FIG. 7, the heat pump unit controller 13 determines whether or not the discharge refrigerant temperature of the compressor 1 detected by the discharge temperature detection means 18 has reached the target discharge temperature R (S31). : No), the boiling operation is performed with the target pressure P1 at the start. If the discharge refrigerant temperature has reached the target discharge temperature R (S31: Yes), it is determined whether or not a predetermined time T3 has elapsed since the discharge refrigerant temperature reached the target discharge temperature R (S32). If the predetermined time T3 has elapsed (S32: Yes), the target pressure of the compressor 1 is changed to the steady-state target pressure P2 (S3). When the predetermined time T3 has not elapsed (S32: No), the boiling operation is performed with the start time target pressure P1 being maintained.

  That is, when the discharge refrigerant temperature reaches the target discharge temperature R and the predetermined time T3 has passed in that state, it is determined that the boiling temperature has become stable, and the target pressure of the compressor 1 is set as the start target pressure. The target pressure P2 is changed from P1 to the steady target pressure P2. As described above, the stability of the discharge temperature after switching the target pressure can be increased by changing the target pressure to the low constant target pressure P2 after the discharge refrigerant temperature reaches the target value. Further, by waiting for the elapse of the predetermined time T3 after the discharge refrigerant temperature reaches the target value, the detection error of the discharge refrigerant temperature by the discharge temperature detection means 18 can be absorbed, and the target pressure can be accurately changed. it can.

(Control of compressor and decompressor)
Next, the rotational speed control of the compressor 1 and the throttle amount control of the decompression device 3 for performing the boiling operation of the heat pump water heater at the target pressure as described above will be described. FIG. 8 is a diagram illustrating a relationship between the target boiling temperature and the refrigerant temperature discharged from the compressor 1. In the present embodiment, the discharge refrigerant temperature of the compressor 1 falls within a preset discharge temperature range with respect to the startup target pressure P1 determined as shown in FIG. 2, FIG. 3 or FIG. In addition, the throttle amount of the decompression device 3 and the rotational speed of the compressor 1 are controlled. The upper limit value and the lower limit value of the discharge temperature range shown in FIG. 8 are determined in advance according to the target boiling temperature.

  In this way, by limiting the upper limit of the refrigerant discharge temperature of the compressor 1, abnormal heating of the drive motor of the compressor 1 can be prevented, and the reliability of the compressor 1 can be improved. Moreover, by restrict | limiting the minimum of the discharge refrigerant | coolant temperature of the compressor 1, the suction | inhalation of the liquid refrigerant to the compressor 1 can be suppressed, and the reliability of the rotating shaft of the compressor 1 can be improved.

  Next, the rotation speed control of the compressor 1 and the throttle amount control of the decompression device 3 will be further described. FIG. 9 is a flowchart for explaining the rotational speed control of the compressor 1 and the throttle amount control of the decompression device 3 in the boiling operation. Roughly, first, the rotational speed of the compressor 1 is determined based on the outside air temperature, and then the rotational speed of the compressor 1 and the throttle amount of the decompression device 3 are corrected according to the target pressure and the discharge temperature range.

  First, when the boiling operation is started, the heat pump unit controller 13 determines the rotational speed of the compressor 1 based on the outside air temperature detected by the outside air temperature detecting means 17 (S41).

  Here, the process of step S41 in FIG. 9 will be further described. FIG. 10 is a diagram for explaining a method for determining the rotational speed of the compressor 1 and shows the relationship between the outside air temperature and the rotational speed of the compressor 1. As shown in FIG. 10, the rotation speed of the compressor 1 is determined in accordance with the outside air temperature within a range between a predetermined upper limit value and lower limit value. More specifically, the rotational speed of the compressor 1 is lowered as the outside air temperature becomes higher, and the rotational speed of the compressor 1 is raised as the outside air temperature becomes lower.

  Returning to FIG. 9, the description will be continued. Operation is performed at the number of rotations of the compressor 1 determined in step S41, and it is determined whether or not the target pressure has been reached (S42). If the target pressure has been reached (S42: Yes), it is determined whether or not the discharge refrigerant temperature of the compressor 1 detected by the discharge temperature detection means 18 is within a predetermined discharge temperature setting range (S43). ). If the discharge refrigerant temperature of the compressor 1 is within a predetermined discharge temperature setting range (S43: Yes), the operation of the compressor 1 is maintained at the same rotation speed. That is, if both the discharge refrigerant pressure and the discharge refrigerant temperature of the compressor 1 are values in a predetermined range, the state is maintained.

  If the discharge refrigerant temperature of the compressor 1 is not within the predetermined discharge temperature range (S43: No), the rotation speed of the compressor 1 is decreased by a predetermined value (S45), and the process returns to step S42. That is, when the discharge refrigerant pressure of the compressor 1 reaches the target pressure but the discharge refrigerant temperature is outside the set range, the discharge refrigerant temperature of the compressor 1 is reduced by decreasing the rotation speed of the compressor 1. I try to lower it.

  In step S42, if the discharge pressure detected by the pressure detection device 5 has not reached the target pressure (S42: No), the discharge refrigerant temperature of the compressor 1 detected by the discharge temperature detection means 18 is a predetermined value. It is determined whether or not the upper limit has been reached (S46). If the discharged refrigerant temperature has reached the predetermined upper limit (S46: Yes), the rotational speed of the compressor 1 is increased (S47), and the process returns to step S42. That is, when the discharge refrigerant pressure of the compressor 1 has not reached the target pressure, but the discharge refrigerant temperature has reached the upper limit value, the discharge refrigerant pressure is reduced by increasing the rotation speed of the compressor 1. It tries to be close to the target pressure.

  If the discharge refrigerant temperature of the compressor 1 has not reached the upper limit value (S46: No), the throttle amount of the decompression device 3 is increased by a predetermined amount (S48), and the process returns to step S42. That is, when the discharge refrigerant pressure of the compressor 1 does not reach the target pressure and the discharge refrigerant temperature does not reach the upper limit value, the refrigerant circulation is increased by increasing the throttle amount of the decompression device 3. The discharge refrigerant pressure is increased by adjusting the amount.

  In addition, when the discharge refrigerant | coolant pressure detected with the pressure detection apparatus 5 in step S42 is larger than a target pressure, you may make the amount of throttling of the decompression device 3 small, and may reduce discharge refrigerant pressure.

  Further, the control interval of the decompression device 3 and the flow rate change amount (throttle amount) of the refrigerant may be changed between the start-up operation and the steady operation. That is, the control interval is made shorter during start-up operation than during steady operation. In addition, during the start-up operation, the amount of change in the refrigerant flow rate is made larger than that during the steady operation. By doing in this way, at the time of start-up operation, it becomes possible to advance the rise of the discharge refrigerant temperature and the discharge refrigerant pressure of the compressor 1, and it is possible to advance the rise of the boiling temperature and the boiling ability.

  DESCRIPTION OF SYMBOLS 1 Compressor, 2 Refrigerant-water heat exchanger, 3 Pressure reducing device, 4 Evaporator, 5 Pressure detection device, 6 Fan motor, 7 Fan, 8 Boiling temperature detection means, 9 Feed water temperature detection means, 10 Hot water circulation device, DESCRIPTION OF SYMBOLS 11 Operation part, 12 Tank unit control part, 13 Heat pump unit control part, 14 Hot water tank, 15 Refrigerant piping, 16 Hot water circulation piping, 17 Outside air temperature detection means, 18 Discharge temperature detection means, 100 Heat pump unit, 200 Tank unit.

Claims (10)

A heat pump unit having a refrigerant circuit in which a compressor, a refrigerant-water heat exchanger, a decompression device, and an evaporator are sequentially connected; and a high-pressure detecting unit that detects a discharge refrigerant pressure discharged from the compressor;
A tank unit having a hot water tank for storing hot water heated by the refrigerant-water heat exchanger;
A hot water circulation device connected between the refrigerant-water heat exchanger and the hot water tank;
In the heat pump water heater with
A heat pump unit control means for controlling at least one of the rotational speed of the compressor and the throttle amount of the decompression device so that the discharged refrigerant pressure detected by the high pressure detection means becomes a preset target pressure ;
A discharge temperature detecting means for detecting a discharge refrigerant temperature discharged from the compressor ,
Two types of target pressures are set in advance in a start-up operation and a steady operation performed following the start-up operation, and the target pressure is set higher in the start-up operation than in the normal operation ,
The heat pump unit control means includes
When the discharge refrigerant pressure has not reached the target pressure during the start-up operation, the rotation speed of the compressor is increased when the discharge refrigerant temperature has reached a predetermined upper limit value, and the discharge refrigerant temperature is set to a predetermined upper limit value. The heat pump hot water supply apparatus is characterized in that control is performed to increase the throttle amount of the pressure reducing device when the pressure has not reached . The heat pump hot water supply apparatus according to claim 1, wherein a target pressure during the start-up operation is adjusted according to a target boiling temperature of hot water heated by the refrigerant-water heat exchanger. An outside air temperature detecting means for detecting the outside air temperature around the heat pump unit;
The heat pump hot-water supply apparatus according to claim 1, wherein a target pressure during the start-up operation is adjusted according to an outside air temperature detected by the outside air temperature detecting means. The heat pump hot-water supply apparatus according to any one of claims 1 to 3, wherein after a predetermined time has elapsed since the start of the start-up operation, the target pressure during the start-up operation is switched to a target pressure during steady operation. Boiling temperature detection means for detecting the temperature of hot water heated by the refrigerant-water heat exchanger,
When the boiling temperature detected by the boiling temperature detecting means reaches a target boiling temperature and becomes stable, the target pressure at the start-up operation is switched to the target pressure at the steady operation. The heat pump hot-water supply apparatus as described in any one of Claims 1-3 which do. A discharge temperature detecting means for detecting a refrigerant temperature discharged from the compressor;
The refrigerant temperature detected by the discharge temperature detecting means is switched from the target pressure at the start-up operation to the target pressure at the steady operation when the refrigerant temperature reaches the target discharge temperature and becomes stable. The heat pump hot-water supply apparatus as described in any one of Claims 1-3. The said control means controls the amount of throttling of the said decompression device so that the discharge refrigerant temperature of the compressor becomes a value within a preset discharge temperature range. The heat pump hot water supply apparatus according to claim 1. The said control means controls the rotation speed of the said compressor so that the discharge refrigerant | coolant temperature of the said compressor may become a value within the preset discharge temperature range. The any one of Claims 1-6 characterized by the above-mentioned. The heat pump hot water supply apparatus according to claim 1. The heat pump hot-water supply apparatus according to any one of claims 1 to 8, wherein a control interval of a throttle amount of the decompression device is shorter during the start-up operation than during the steady operation. 10. The throttle amount of the decompression device is controlled during the start-up operation so that the amount of change in the refrigerant flow rate is greater than during the steady operation. 10. Heat pump water heater.

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