JP4839141B2 - Heat pump water heater - Google Patents

Description

  The present invention relates to a heat pump hot water supply apparatus.

  The heat pump hot water supply apparatus is roughly classified into a hot water storage type heat pump hot water supply apparatus and an instantaneous heat pump hot water supply apparatus. In the conventional example of the hot water storage type heat pump water heater among them, the heating capacity is 4.5 to 6 kW, and it is heated to 65 to 90 ° C. hot water using cheap nighttime power in the midnight hours, and 300 to 480 L in the hot water storage tank. Store hot water. During hot water supply during the day, water is mixed with high-temperature hot water stored in a hot water storage tank. An example of such a hot water storage type heat pump hot water supply apparatus is described in Patent Document 1.

  An example of an instantaneous heat pump water heater is described in Patent Document 2. In the heat pump hot water supply apparatus described in this publication, the temperature of water introduced from a water supply pipe is raised by a water heat exchanger and hot water is supplied to a use terminal as it is, and a large hot water storage tank is not required. Until the pressure condition immediately after the start of operation of the heat pump circuit is stabilized, sufficient heat of condensation cannot be generated to warm the water, so the hot water stored in the small hot water supply tank can be Hot water is mixed with water from the exchanger.

  Another example of a conventional instantaneous heat pump water heater is described in Patent Document 3. The heat pump hot water supply apparatus described in this publication is required in a heat exchanger having a water flow path for exchanging heat with a refrigerant flow path of a heat radiator of a heat pump cycle in order to enable hot water supply having both responsiveness and stability. Load setting means for setting the heating amount and heating control means for controlling the heating amount of the heat exchanger according to the set value of the load setting means.

Japanese Patent Laying-Open No. 2005-147608 JP 2003-279133 A JP 2003-240344 A

  In the hot water storage type heat pump hot water supply device described in Patent Document 1, high-temperature hot water that has been heated and stored in advance is used. Therefore, if the same amount of hot water is consumed, the energy efficiency does not change depending on the hot water supply pattern. This is because energy efficiency and the hot water supply pattern are independent of each other. As a result, the energy efficiency of hot water supply is the same regardless of whether it is a hot water supply pattern such as hand-washing or a hot water supply pattern with a long continuous hot water supply such as a hot water bath. When the hot water stored in the hot water storage tank is used up, it is possible to use the energy efficiency constant regardless of the length of time from the start of hot water supply to the stop of hot water supply. However, when the hot water in the hot water storage tank is used up, the heating capacity is small, so that it cannot be heated up immediately and a problem of running out of hot water occurs.

  On the other hand, in the instantaneous heat pump device described in Patent Document 2, for example, it has a heating capacity about 5 times that of a hot water storage type, and when it is desired to use hot water, it can be boiled as much as necessary. Small size and space saving is possible without the need for a large hot water storage tank. In addition, when the water heating by the heat pump reaches the set temperature, the hot water from the hot water supply tank is stopped and the hot water is supplied only from the heat pump, so that hot water can be continuously supplied and there is no fear of running out of hot water.

  However, in the instantaneous heat pump hot water supply device described in Patent Document 2, the refrigerant gas pressurized and heated by the compressor at the start of the heat pump is also consumed to warm the compressor and the water refrigerant heat exchanger, The amount of heating to the hot water that is originally required is reduced. As a result, the COP, which is the ratio of the water heating capacity to the power consumption of the heat pump, so-called energy efficiency is lowered. In a hot water supply pattern in which the operation is stopped when the heat pump starts up, energy efficiency decreases.

  Also, in the instantaneous water heater type heat pump water heater described in Patent Document 3, immediately after the start of hot water supply, the heat of the refrigerant compressed to a high temperature by the compressor is transferred to the compressor and the water refrigerant heat exchanger. It is spent heating the compressor and water refrigerant heat exchanger. As a result, the COP of the heat pump hot water supply apparatus immediately after the start of hot water supply is lowered, and it may be difficult to supply hot water at a temperature desired by the user in an amount desired.

  The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to prevent hot water shortage and maintain high energy efficiency regardless of the usage pattern of hot water in a heat pump hot water supply apparatus.

The present invention relates to a heat pump water heater having a heat pump refrigerant circuit and a hot water storage tank for storing hot water heated by the heat pump refrigerant circuit, wherein the heat pump refrigerant circuit has two water refrigerant heats for heat exchange between the refrigerant and water. A plurality of on-off valves having an exchanger, and capable of switching between a serial connection and a parallel connection of the water flow paths and the refrigerant flow paths of the two water-refrigerant heat exchangers, and a heating target in the heat pump refrigerant circuit. A control device that controls according to temperature, two hot water refrigerant heat exchangers are connected in series when hot water is supplied at a high target temperature, and two hot water refrigerant heat exchanges when hot water is supplied at a low target temperature The devices are connected in parallel.

In addition, when the control device operates the heat pump refrigerant circuit to supply hot water to the hot water storage tank, two water refrigerant heat exchangers are connected in series, and when the heat pump refrigerant circuit operates to supply hot water to the hot water supply terminal, 2 It is desirable to connect the water refrigerant heat exchangers in parallel. In addition , it has a flow rate detection means for detecting the use of hot water at a hot water supply terminal connected to the heat pump hot water supply device, the control device can control the heat pump refrigerant circuit, and the flow rate detection means detects the use of hot water at the hot water supply terminal. It is desirable to control the heat pump refrigerant circuit so that hot water is supplied only from the hot water storage tank until a predetermined time elapses. Furthermore, it is desirable that when the hot water supply terminal is connected to the bathtub and fills the bathtub, the control device controls to start the heat pump refrigerant circuit as soon as the flow rate detecting means detects the hot water supply. Also, the control device includes a Turkey to paralleling control a plurality of the on-off valve two coolant-refrigerant heat exchanger before operating the heat pump refrigerant circuit is desirable.

Alternatively, the present invention provides a heat pump refrigerant circuit having a water refrigerant heat exchanger that exchanges heat between refrigerant compressed by a compressor and water, a hot water storage tank that stores hot water heated by the water refrigerant heat exchanger, and water refrigerant heat. a water supply means for supplying water to the exchanger and the hot water storage tank, the heat pump water heater with a hot water supply means for supplying hot water sent from the water-refrigerant heat exchanger and the hot water storage tank, the less water-refrigerant heat exchanger also refrigerant flow path are formed in plural, when the parallel connection and the series connection of the plurality forming refrigerant flow path and can be switched in accordance with a target temperature of the heating in the heat pump refrigerant circuit and hot water at a high target temperature When the refrigerant flow paths are connected in series and hot water is supplied at a low target temperature, the refrigerant flow paths are connected in parallel.

Also, when the store hot water that is heated in the hot water storage tank, refrigerant flow path formed a plurality of coolant-refrigerant heat exchanger connected in series, when the hot water in the hot-water supply terminal by operating a heat pump refrigerant circuit, refrigerant it is desirable to parallel connection of the flow path. Moreover, it is desirable to provide a control means for starting the compressor after a predetermined time has elapsed since the hot water supply was started. Also, there are a plurality of hot water supply means, one hot water supply means is connected to the bath, and the other hot water supply means is connected to other than the bath, and hot water is supplied from the hot water supply means connected to the bath. It is desirable that the control means can change the time for starting the compressor depending on the time and when hot water is supplied from a hot water supply means connected to other than the bath.

Alternatively, the present invention provides a heat pump water heater having a heat pump refrigerant circuit and a hot water storage tank for storing hot water heated by the heat pump refrigerant circuit, wherein the heat pump refrigerant circuit includes two waters for heat exchange between the refrigerant and water. A plurality of on-off valves that have a refrigerant heat exchanger and that can switch between series connection and parallel connection of the two water refrigerant heat exchangers and control the on-off valves according to the target temperature of heating in the heat pump refrigerant circuit When the hot water is supplied at a high target temperature, two water refrigerant heat exchangers are connected in series, and when the hot water is supplied at a low target temperature, the two water refrigerant heat exchangers are connected in parallel. A heat pump hot water supply device having flow rate detecting means for detecting use of hot water at a hot water supply terminal connected to the heat pump hot water supply device, and the control device can control the heat pump refrigerant circuit. Both control the heat pump refrigerant circuit to supply hot water only from the hot water storage tank until a predetermined time has elapsed after the flow rate detecting means detects use of the hot water supply at the hot water supply terminal, while the control device connects the hot water supply terminal to the bathtub. When the hot water is filled in the lever, the heat pump refrigerant circuit is controlled to start as soon as the flow rate detecting means detects hot water supply.

Alternatively, the present invention provides a heat pump refrigerant circuit having a water refrigerant heat exchanger that exchanges heat between refrigerant compressed by a compressor and water, a hot water storage tank that stores hot water heated by the water refrigerant heat exchanger, and water refrigerant heat. In a heat pump water heater comprising a water supply means for supplying water to the exchanger and the hot water storage tank, and a hot water supply means for supplying hot water sent from the water refrigerant heat exchanger and the hot water storage tank, at least the water flow path of the water refrigerant heat exchanger And a plurality of the refrigerant flow paths are formed, and the parallel connection and series connection of the plurality of formed flow paths can be switched according to the target temperature of heating in the heat pump refrigerant circuit, and at a high target temperature. When supplying hot water, the flow path is connected in series, and when supplying hot water at a low target temperature, the heat pump hot water supply apparatus is connected in parallel with the flow path. It has a control means for starting the machine, has a plurality of hot water supply means, one hot water supply means is connected to the bath, and the other hot water supply means is connected to something other than the bath, connected to the bath The control means can change the time for starting the compressor depending on whether the hot water is supplied from the hot water supply means or the hot water supply means connected to other than the bath.

  According to the present invention, since the start timing of the compressor included in the heat pump hot water supply apparatus is adjusted, the heat pump hot water supply apparatus can be prevented from running out of hot water, and the heat pump hot water supply apparatus can maintain high energy efficiency regardless of the hot water usage pattern.

Hereinafter, an embodiment of a heat pump hot water supply apparatus according to the present invention will be described with reference to the drawings. 1 and 2 are system diagrams of the heat pump water heater 100. FIG. The heat pump hot water supply apparatus 100 is roughly divided into a heat pump refrigerant circuit 90 and a water supply circuit 91, a hot water supply circuit 92, a bath hot water filling circuit 93, a bath reheating heating circuit 94, a bath reheating heat absorption circuit 95, and a tank boiling back circuit 96. Yes. The refrigerant of the heat pump refrigerant circuit 90 is carbon dioxide, so that hot water can be supplied.

Next, the configuration of each circuit will be described below. The heat pump refrigerant circuit 90 includes a compressor 1 that compresses the refrigerant into a high-temperature refrigerant, heat exchange between the refrigerant that has been compressed by the compressor 1 and has reached a high temperature and water (water supply) supplied for hot water supply. 1 water refrigerant heat exchanger 2 and second water refrigerant heat exchanger 3, expansion valve 4 for decompressing the refrigerant exiting these water refrigerant heat exchangers 2, 3 and low temperature and low pressure refrigerant exiting expansion valve 4 The evaporator 5 for evaporating the water is connected by a refrigerant pipe. The compressor 1 is capable of capacity control by inverter control, and the rotation speed is variable from a low speed (for example, 1000 rpm) to a high speed (for example, 6000 rpm). The evaporator 5 is an air refrigerant heat exchanger, and exchanges heat between a large amount of outdoor air and the decompressed refrigerant by the outdoor fan 6.

The first water refrigerant heat exchanger 2 and the second water refrigerant heat exchanger 3 have refrigerant side heat transfer tubes 2a, 3a and water side heat transfer tubes 2b, 3b, and the refrigerant side heat transfer tubes 2a, 3a. The refrigerant flow and the water flow in the water-side heat transfer tubes 2b and 3b are opposed to each other. Then, the high-temperature and high-pressure refrigerant and the low-temperature water exchange heat. Here, in order to switch whether the refrigerant side heat transfer tubes 2a and 3a of the first and second water refrigerant heat exchangers 2 and 3 are connected in series or in parallel, the second water is provided in the refrigerant circuit. A first refrigerant side electromagnetic valve 40 a is arranged on the inlet side of the refrigerant heat exchanger 3, and a refrigerant side electromagnetic valve 41 a is arranged on the outlet side of the first water refrigerant heat exchanger 2. Moreover, the refrigerant | coolant side check valve 42a is arrange | positioned at the bypass flow path of the 1st water refrigerant | coolant heat exchanger.

  More specifically, the inlet side of the refrigerant side heat transfer tube 2a of the first water refrigerant heat exchanger 2 is connected to the compressor 1 by a refrigerant pipe. Furthermore, the inlet side of the refrigerant side heat transfer tube 2a is connected to the inlet side of the refrigerant side heat transfer tube 3a of the second water refrigerant heat exchanger 3 via the first refrigerant side electromagnetic valve 40a. The outlet side of the refrigerant-side heat transfer tube 3a of the second water-refrigerant heat exchanger 3 is connected to the expansion valve 4 through a refrigerant pipe. Further, the outlet side of the refrigerant side heat transfer tube 3a is connected to the outlet side of the refrigerant side heat transfer tube 2a of the first water refrigerant heat exchanger 2 via the second refrigerant side electromagnetic valve 41a. The outlet side of the refrigerant side heat transfer tube 2a of the first water refrigerant heat exchanger 2 is connected to the inlet side of the refrigerant side heat transfer tube 3a of the second water refrigerant heat exchanger 3 via the refrigerant side check valve 42a. ing. The check valve 42a acts so that the refrigerant flows only in the direction from the refrigerant side heat transfer tube 2a to the refrigerant side heat transfer tube 3a.

  The first and second water refrigerant heat exchangers 2 and 3 have water-side heat transfer tubes 2b and 3b, and the water-side heat transfer tubes 2b and 3b can be switched between being connected in series and being connected in parallel. Thus, the water side solenoid valve 40b is arrange | positioned at the exit side of the water side heat exchanger tube 3b of the 2nd water refrigerant heat exchanger 3, and the water side heat exchanger tube 2b of the 1st water refrigerant heat exchanger 2 is arrange | positioned. A second water side electromagnetic valve 41b is arranged on the inlet side. A check valve 42 b is disposed in the bypass flow path of the second water refrigerant heat exchanger 2.

More specifically, the inlet side of the water side heat transfer tube 3b of the second water refrigerant heat exchanger 3 is connected to the water supply circuit 91 by a water pipe. Furthermore, the inlet side of the water side heat transfer tube 3b is connected to the inlet side of the water side heat transfer tube 2b of the first water refrigerant heat exchanger 2 via the second water side electromagnetic valve 41b. The outlet side of the water side heat transfer tube 2b of the first water refrigerant heat exchanger 2 is connected to the hot water supply circuit 92 by a water pipe. Further, the outlet side of the water side heat transfer tube 2b is connected to the outlet side of the water side heat transfer tube 3b of the second water refrigerant heat exchanger 3 via the first water side electromagnetic valve 40b. The outlet side of the water side heat transfer tube 3b of the second water refrigerant heat exchanger 3 is connected to the inlet side of the water side heat transfer tube 2b of the first water refrigerant heat exchanger 2 via the water side check valve 42b. ing. The check valve 42b acts so that water flows only in the direction from the water side heat transfer tube 3b to the water side heat transfer tube 2b.

When the water refrigerant heat exchangers 2 and 3 are connected in parallel, the low temperature water at the inlets of the water refrigerant heat exchangers 2 and 3 is gradually heated when passing through the water side heat transfer tubes 2b and 3b. At the outlets of the water-refrigerant heat exchangers 2 and 3, the temperature is raised to a predetermined temperature set by the operation control means described later. When the water refrigerant heat exchangers 2 and 3 are connected in series, the low temperature water at the inlet of the water refrigerant heat exchanger 3 is gradually heated when passing through the water side heat transfer tubes 3b and 2b , At the outlet of the heat exchanger 2, the temperature is raised to a predetermined temperature set by the operation control means.

  The water supply circuit 91 includes a water supply fitting 11 for taking in clean water from the outside, a pressure reducing valve 12 for adjusting the picked-up clean water to an appropriate water pressure, a feed water flow rate sensor 13 for measuring the amount of feed water, and how much the feed water is water-refrigerant heat exchange A water refrigerant heat exchanger flow sensor 15 for measuring whether the water is flowing in the water heaters 2 and 3, and a check valve 14 for preventing the water from flowing back from the water refrigerant heat exchangers 2 and 3 to the water supply fitting 11 side. Have. From the water supply fitting 11 to the water side heat transfer pipes 2b and 3b of the water refrigerant heat exchangers 2 and 3 are connected by a water pipe, and these members are provided in the water pipe.

The hot water supply circuit 92 includes a water pipe from the water side heat transfer pipes 2b and 3b of the water refrigerant heat exchangers 2 and 3 to the hot water supply fitting 19 connected to the hot water supply pipe outside the apparatus, and each member. Between the water refrigerant heat exchangers 2 and 3 and the hot water supply fitting 19, a hot water storage tank 21 for storing hot water heated by the water side heat transfer tubes 2b and 3b, and hot water and hot water heated by the water side heat transfer tubes 2b and 3b are stored. The first hot water mixing valve 16 used for mixing the hot water stored in the tank 21 and the second hot water used for mixing the water supplied from the water supply circuit 91 with the hot water passing through the first hot water mixing valve 16. A mixing valve 17 and a flow rate adjusting valve 18 that adjusts the flow rate of the hot water passing through the second hot water mixing valve 17 are arranged.

  One inlet of the first hot water mixing valve 16 is connected to the hot water storage tank 21. The hot water storage tank 21 is used for storing hot water previously heated by the water refrigerant heat exchangers 2 and 3 of the tank boiling back circuit 96. The first hot / cold water mixing valve 16 mixes hot water of about 60 to 90 ° C. stored in the hot water storage tank 21 with hot water supplied from the water / refrigerant heat exchangers 2 and 3 according to a command from the operation control means. Used for. Specifically, from the first hot water / water mixing valve 16, hot water at a predetermined temperature set by the operation control means until the hot water heated by the water / refrigerant heat exchangers 2 and 3 is heated to a desired temperature. Is leaked.

  When the temperature desired by the user and the amount of hot water (hot water supply load) exceed the heating capacity of the heat pump refrigerant circuit 90, the hot water that has not reached the desired temperature supplied from the water refrigerant heat exchangers 2 and 3 is used. The hot water stored in the hot water storage tank 21 is always mixed. Then, hot water having a predetermined temperature set by the operation control means is supplied to the user.

  One inlet of the second hot water / mixing valve 17 is connected to a water pipe. This water pipe is branched from the water supply circuit 91. In the second hot water mixing valve 17, hot water mixed by the first hot water mixing valve 16 and water branched and supplied from the water supply circuit 91 are mixed according to a command from the operation control means. The operation control means opens and closes the first hot water mixing valve 16 and the second hot water mixing valve 17 in order to discharge hot water having a predetermined hot water supply temperature (about 35 to 60 ° C.) to the hot water terminal through the hot water supply fitting 19. To control.

The bath hot water filling circuit 93 branches off from a pipe line connecting the flow rate adjusting valve 18 of the hot water supply circuit 92 and the hot water supply fitting 19, and from the branching portion 19 a to the incoming / outgoing hot metal fitting 35 for supplying hot water to the bathtub 36. Contains. In the piping of the bath hot water circuit 93, a hot water solenoid valve 31, a flow switch 32, a bath circulation pump 33, and a water level sensor 34 are sequentially arranged.

  The hot water solenoid valve 31 is used to guide hot water from the branch portion 19a to the bathtub 36 side. The flow switch 32 detects the flow of hot water in the bath hot water filling circuit 93. The bath circulation pump 33 is used to supply hot water from the bathtub 36 to the water-refrigerant heat exchanger 2 when reheating. The water level sensor 34 detects the water level of the hot water poured into the bathtub 36. The bath metal fitting 35 and the bath circulation adapter 36a attached to the bathtub 36 are connected by a water pipeline.

  The bath reheating heating circuit 94 is a circuit for reheating the hot water in the bathtub 36, and has a bath reheating heat exchanger 29. The in-machine circulation pump 23 connected to the outlet side of the secondary refrigerant side heat transfer tube 29a of the bath reheating heat exchanger 29 pressurizes the water in the water pipe line and the water side heat transfer tubes of the water refrigerant heat exchangers 2 and 3. 2b and 3b. Water is heated in the water side heat transfer tubes 2b and 3b. Heated and heated water (high temperature water) passes through a follow-up electromagnetic valve 27 and a check valve 28 provided in a pipe branched from the hot water supply circuit 92. Here, while the bath reheating heating circuit 94 is in operation, the reheating electromagnetic valve 27 is in an open state.

  After passing through the check valve, the high-temperature water flows into the secondary refrigerant-side heat transfer tube 29a of the bath chase heat exchanger 29. In the bath reheating heat exchanger 29, the flow of high temperature water in the secondary refrigerant side heat transfer tube 29a and the flow of hot water in the bathtub water side heat transfer tube 29b form a counter flow. The high-temperature water that has exchanged heat with the hot water in the bathtub water-side heat transfer tube 29 b is lowered in temperature to become low-temperature water, and flows into the in-machine circulation pump 23. Thereafter, the low-temperature water is returned to the water-refrigerant heat exchangers 2 and 3 from the water pipe connected to the downstream side of the check valve 14 of the water supply circuit 91. Thereafter, water continues to circulate through the bath reheating heating circuit 94 while the bath renewal operation is continued.

The bath reheating heat absorption circuit 95 is a circuit that heats the hot water in the bathtub 36, and guides the bath water from the bath circulation adapter 36 a provided in the bathtub 36 to the bath reheating heat exchanger 29 through the inlet / outlet hot water fitting 35. The bathtub water taken out from the bathtub 36 is guided to the bath circulation pump 33 through the water level sensor 34. The bath circulation pump 33 pressurizes the bath water and supplies it to the bath reheating heat exchanger 29 via the flow switch 32. Here, the hot water solenoid valve 31 provided in the bath hot water filling circuit 93 is closed, and the bath water is guided to the bath reheating heat exchanger 29. The bath water is heated when flowing through the bath water side heat transfer tube 29 b of the bath reheating heat exchanger 29, and is returned to the bath circulation adapter 36 a via the hot water inlet / outlet fitting 37.

  The tank boiling back circuit 96 is a circuit that guides the hot water heated by the water / refrigerant heat exchangers 2 and 3 to the hot water storage tank 21. The tank boiling back circuit 96 includes a hot water storage tank 21, an in-machine circulation pump 23 for feeding hot water to the hot water storage tank, and a first hot water mixing valve 16. When the tank boiling back circuit 96 is operated, the reheating electromagnetic valve 27 of the bath reheating heating circuit 94 is closed. In the first hot water / water mixing valve 16, the water / refrigerant heat exchangers 2 and 3 and the hot water storage tank 21 are communicated with each other. The second hot water / mixing valve 17 shuts off the first hot water / mixing valve 16 and the water supply side. In this state, the in-machine circulation pump 23 is operated to supply the water in the hot water storage tank 21 from the lower part of the hot water storage tank 21 to the water / refrigerant heat exchangers 2 and 3. The hot water stored in the hot water storage tank 21 is heated to about 60 to 90 ° C. by the water refrigerant heat exchangers 2 and 3, and is returned to the upper part of the hot water storage tank 21 through the first hot water / water mixing valve 16.

  In addition, when starting up the heat pump refrigerant circuit 90, the heating capability of the heat pump refrigerant circuit 90 is not sufficient. Therefore, a preheating operation is performed using the bath reheating heating circuit 94 until the water refrigerant heat exchangers 2 and 3 can heat water at a predetermined temperature. Specifically, the reheating electromagnetic valve 27 is opened, and the water refrigerant heat exchangers 2 and 3 side of the first hot water mixing valve 16 and the hot water storage tank 21 are shut off. The first hot water mixing valve 16 and the water supply side of the second hot water mixing valve 17 are also shut off. In this state, the in-machine circulation pump 23 is operated so that water circulates between the water-refrigerant heat exchangers 2 and 3 and the bath reheating heat exchanger 29.

  A switching operation using a control device (not shown) when operating each circuit will be described below. The control device operates / stops the heat pump refrigerant circuit 90. Moreover, the rotational speed of the compressor 1 and the opening degree of the expansion valve 4 are controlled. Further, it controls water-related equipment such as hot and cold mixing valves 16 and 17 and a flow rate adjusting valve 18 of the hot water supply circuit.

  The heat pump hot water supply apparatus 100 shown in the present embodiment is provided with a compressor discharge pressure sensor 51 on the discharge side of the compressor 1 of the heat pump refrigerant circuit 90. Furthermore, the heat pump hot water supply apparatus 100 has a large number of temperature sensors.

In the heat pump refrigerant circuit 90, the compressor discharge temperature sensor 50 is disposed on the discharge side of the compressor 1, the evaporator refrigerant inlet temperature sensor 52 is disposed on the refrigerant inlet side of the evaporator 5, and the evaporator refrigerant outlet temperature sensor is disposed on the refrigerant outlet side. 53 and an outside air temperature sensor 54 are provided in the vicinity of the evaporator 5. In the water supply circuit 91, a water supply temperature sensor 60 is provided in the vicinity of the water supply fitting 11, and a water refrigerant heat exchanger water inlet temperature sensor 61 is provided in the water supply line and upstream of the water inlet side of the water refrigerant heat exchangers 2 and 3. Each is provided. In the hot water supply circuit 92, the water refrigerant heat exchanger water outlet temperature sensor 62 is provided downstream of the water outlet side of the water refrigerant heat exchangers 2 and 3, and the hot water supply between the first hot water mixing valve 16 and the second hot water mixing valve 17. The mixing temperature sensor 63 in the line, the hot water supply temperature sensor 64 in the hot water supply line downstream of the second hot water mixing valve 17, and the tank temperature sensors 65a, 65b, 65c in the hot water storage tank 21 are changed in the height direction. Is provided.

In heat pump hot water supply apparatus 100 in which various sensors are arranged in this way, when a user sets a desired hot water supply temperature Tws using a remote controller (not shown) disposed in the house, the control device supplies hot water at a desired temperature from the hot water supply facility. Each valve is controlled so that hot water can be supplied. That is, the control device sets the target temperature of the hot water supply temperature sensor 64 provided downstream of the second hot water / water mixing valve 17 to a temperature (Tws + α0) higher by α0 than the set hot water supply temperature. The target temperature of the mixing temperature sensor 63 provided between the first hot water mixing valve 16 and the second hot water mixing valve 17 is set to a temperature (Tws + α0 + α1) higher by α1 than this temperature. The target temperature of the water-refrigerant heat exchanger water outlet temperature sensor 62 is set to a temperature (Tws + α0 + α1 + α2) that is higher by α2.

  In this embodiment, in consideration of heat radiation in the water pipeline, the target temperature is set higher as the upstream side of the hot water supply circuit 92 becomes closer to the water refrigerant heat exchangers 2 and 3. Even if the outlet temperature of the water-side heat transfer tubes 2b, 3b of the water-refrigerant heat exchangers 2, 3 and the mixing temperature of the hot water flowing out of the first hot water / water mixing valve 16 fluctuate somewhat due to disturbance or the like, the desired hot water supply temperature Since the temperature is set slightly higher, it can be adjusted to a desired temperature by controlling the amount of water mixed with the hot water flowing into the second hot water mixing valve 17. As a result, hot water supply with little temperature fluctuation can be realized.

  In the operation for operating the tank boiling back circuit 96, the target temperature of the water / refrigerant heat exchanger water outlet temperature sensor 62 is set to a temperature of 60 to 90 ° C. in accordance with conditions such as the season and the amount of hot water used.

  When operating the heat pump refrigerant circuit 90, the rotation speed of the compressor 1 is controlled. Since the heat capacity of the refrigerant circulation system including the water refrigerant heat exchangers 2 and 3 is large, even if the rotation speed of the compressor 1 is changed, the water outlet temperature of the water refrigerant heat exchangers 2 and 3 does not change immediately. The response speed of this water outlet temperature is slow. Therefore, the discharge pressure of the compressor 1, which has characteristics related to the water outlet temperature of the water-refrigerant heat exchangers 2 and 3 and has a fast response speed, is determined as a control target. In the case of a hot water storage type heat pump hot water supply apparatus, hot water having a desired temperature can be instantaneously supplied. However, in the instantaneous type heat pump hot water supply apparatus, the supply timing depends on the rising characteristics of the heat pump refrigerant circuit 90. Therefore, the rising characteristics are improved as follows.

The discharge pressure of the compressor 1 is higher as the water outlet temperature of the water refrigerant heat exchangers 2 and 3 is higher. The target discharge pressure Pd0 is expressed as (Equation 1) as a function of the water outlet temperature target value Twh (= Tws + α0 + α1 + α2) of the water refrigerant heat exchangers 2 and 3.
Pd0 = f (Twh) (Formula 1)
The rotational speed of the compressor 1 is controlled so that the deviation ΔEpd (= Pd0−Pd) between the target discharge pressure Pd0 and the actual discharge pressure Pd becomes zero. At this time, for example, the rotational speed of the compressor 1 is increased or decreased as a function of the deviation ΔEpd and (deviation ΔEpd−previous deviation ΔEpd).

  Even if the flow rate of water flowing through the heat pump refrigerant circuit 90 changes and the actual discharge pressure Pd reaches the target discharge pressure Pd0, it is also expected that the water outlet temperature of the water refrigerant heat exchanger 2 is deviated from the target value. Therefore, the target discharge pressure Pd0 is corrected as needed so that the water outlet temperature of the water-refrigerant heat exchanger 2 approaches the target value.

  That is, when the rotational speed of the compressor 1 is controlled, a desired flow rate is determined by the opening of a user's faucet, etc., and a desired hot water supply temperature Tws is set from the remote controller, and the water refrigerant is based on these set temperature and flow rate. Control is performed so that the water outlet temperature target value Twh of the heat exchanger 2 is realized. The degree of superheat of the opening degree of the expansion valve 4 is controlled. That is, the opening degree of the expansion valve 4 is controlled so that the degree of superheat that is the temperature difference between the refrigerant outlet temperature and the refrigerant inlet temperature of the evaporator 5 becomes a predetermined value.

  During the hot water supply operation for operating the hot water supply circuit 92, the valves 40a to 42b of the water-refrigerant heat exchangers 2 and 3 are switched as follows. FIG. 3 shows a hot water supply operation in which the water-refrigerant heat exchangers 2 and 3 are connected in parallel. The refrigerant and water flow paths are indicated by bold lines. During the hot water supply operation, the first refrigerant side electromagnetic valve 40a and the second refrigerant side electromagnetic valve 41a are opened. When these solenoid valves 40a and 41a are opened, a refrigerant flow is generated in the refrigerant pipe, and a pressure drop due to the refrigerant flow occurs. As a result, the pressure on the solenoid valve 41a side of the refrigerant check valve 42a is lower than the pressure on the solenoid valve 40a side. The check valve 42a is in a closed state, and the refrigerant side heat transfer tubes 2a and 3a of the water refrigerant heat exchangers 2 and 3 are in a parallel connection state.

  The first water side solenoid valve 40b and the second water side solenoid valve 41b are opened. When these solenoid valves 40b and 41b are opened, a flow of water is generated in the water-side pipeline, and a pressure drop due to the flow of water occurs. As a result, the pressure on the electromagnetic valve 40b side of the water-side check valve 42b becomes lower than the pressure on the electromagnetic valve 41b side. The check valve 42b is closed, and the water-side heat transfer tubes 2b and 3b of the water refrigerant heat exchangers 2 and 3 are also connected in parallel. Accordingly, both the refrigerant flow path and the water flow path of the water refrigerant heat exchangers 2 and 3 are connected in parallel.

  By the way, when the hot water storage operation is performed at 60 ° C., the water-side flow rate and the refrigerant-side flow rate are set to be about one half or less than those when the hot water supply operation is performed at 42 ° C. If the flow paths of the water and refrigerant heat exchangers 2 and 3 are not changed without operating each solenoid valve as in the hot water storage operation after the hot water supply operation, the water side The flow velocity of water or refrigerant in the heat transfer tubes 2b and 3b and the refrigerant side heat transfer tubes 2a and 3a is decreased. As a result, the water side heat transfer coefficient and the refrigerant side heat transfer coefficient also decrease.

  In order to avoid this performance degradation, the water / refrigerant heat exchangers 2 and 3 are changed from parallel connection to series connection during hot water storage operation as shown in FIG. Thick lines indicate refrigerant and water flow paths. When the first refrigerant side solenoid valve 40a and the second refrigerant side solenoid valve 41a are closed during the hot water storage operation, the pressure on the solenoid valve 40a side of the refrigerant check valve 42a is reduced by the pressure drop due to the refrigerant flow. Therefore, the check valve 42a is opened. As a result, the refrigerant side heat transfer tubes 2a, 3a of the water refrigerant heat exchangers 2, 3 are connected in series.

  When the first water-side solenoid valve 40b and the second water-side solenoid valve 41b are closed, the pressure on the solenoid valve 41b side of the water-side check valve 42b is less than the pressure on the solenoid valve 40b side due to the pressure drop due to the flow of water. The check valve 42b is in an open state. The water-side heat transfer tubes 2b and 3b of the water-refrigerant heat exchangers 2 and 3 are connected in series. Therefore, the water refrigerant heat exchangers 2 and 3 are configured in series with the refrigerant and the water flow path. Since the water-refrigerant heat exchangers 2 and 3 are connected in series, the flow velocity of water or refrigerant in the water-side heat transfer tubes 2b and 3b and the refrigerant-side heat transfer tubes 2a and 3a is increased, and the heat transfer coefficient is improved.

In FIG. 5, the performance calculation result of the heat pump hot water supply apparatus 100 at the time of the hot water supply operation at 42 ° C. and the hot water storage operation at 60 ° C. is shown in a table. During hot water storage operation, the flow path of the water-refrigerant heat exchangers 2 and 3 is switched from parallel connection to series connection, so that the heat transfer rate is improved and the refrigerant pressure is reduced.
COP is improved by about 4%. In addition, although pressure loss will increase if it connects in series, the effect by the improvement of a heat transfer rate is larger, and COP which is the efficiency of the heat pump hot-water supply apparatus 100 is improving.

  When the hot water usage time from the hot water supply terminal connected to the hot water supply metal fitting 19, the pouring electromagnetic valve 31, the bathtub metal fitting 37, or the like is as short as several tens of seconds, the compressor 1 is not started. Then, hot water is supplied from the hot water storage tank 21 to the hot water supply terminal. FIG. 6 is a timing chart showing how the heat pump refrigerant circuit 90 is operated / stopped when the hot water supply terminal is opened and closed.

  When a faucet (not shown) connected to the hot water supply fitting 19 is opened, the clean water flowing in from the water supply fitting 11 due to the water pressure becomes the pressure reducing valve 12, the water supply flow rate sensor 13, the check valve 14, and the water refrigerant heat exchanger flow rate. The water flows out from the faucet through the sensor 15, the water refrigerant heat exchanger 2, 3, the first hot / cold water mixing valve 16, the second hot / cold water mixing valve 17, the flow rate adjusting valve 18, and the hot water supply fitting 19. At that time, the compressor 1 of the heat pump refrigerant circuit 90 is not started, for example, only for 30 seconds after the water supply flow rate sensor 13 provided in the hot water supply line detects the water flow. The length of the detection time of the feed water flow sensor 13 is measured by a timer provided in the control device. It goes without saying that this timer may be provided in the water supply flow rate sensor 13.

  Further, a controller (not shown) controls the opening degree of the first hot water mixing valve 16 so that the temperature of the mixed temperature sensor 63 becomes the target temperature (Tws + α0 + α1), and the hot water in the hot water storage tank 21 is controlled by the first hot water mixing valve 16. And unheated water flowing out of the water refrigerant heat exchangers 2 and 3 are mixed. Then, the control device controls the amount of water to be mixed by the downstream second hot water / water mixing valve 17 so that the temperature of the hot water supply temperature sensor 64 becomes the target temperature (Tws + α0). The amount of hot water mixed is adjusted by the second hot water mixing valve 17, and hot water of an appropriate temperature is supplied to the faucet.

According to the present embodiment, the compressor 1 is not started if the hot water supply terminal such as a faucet is used within 30 seconds. Only the hot water in the hot water storage tank 21 made by the hot water storage operation using the tank boiling back circuit 96 is used. Therefore, when the water flow is detected, the use time of the compressor is shortened and frequent start / stop of the compressor 1 can be prevented as compared with the conventional method of starting the compressor 1. Note that the hot water storage tank 21 stores the heat pump refrigerant circuit 90 and the in-machine circulation pump 23 when there is no hot water supply request. At that time, the water in the hot water storage tank 21 circulates in the water path in the order of the in-machine circulation pump 23, the water / refrigerant heat exchangers 2 and 3, and the first hot water / water mixing valve 16. If the hot water supply terminal is used within 30 seconds, only the hot water in the hot water storage tank 21 is used, so that the ratio of the hot water storage operation becomes large in the total hot water supply load. According to this embodiment, since the water refrigerant heat exchangers 2 and 3 are switched and used, the energy efficiency of the hot water storage operation is improved.

When using hot water continuously for 30 seconds or more from the hot water supply terminal, the heat pump refrigerant circuit 90 is operated. That is, the compressor 1 is started when 30 seconds have elapsed after the water supply flow rate sensor 13 detects the water flow. Until the heat pump refrigerant circuit 90 starts up, the hot water supplied from the heat pump refrigerant circuit 90 does not reach the predetermined target temperature set by the control device. Therefore, hot water heated by the water / refrigerant heat exchangers 2 and 3 and hot water stored in the hot water storage tank 21, for example, about 60 ° C. are mixed, and the temperature detected by the mixing temperature sensor 63 is a predetermined target temperature. The opening degree of the first hot and cold water mixing valve 16 is adjusted so that

  When the compressor 1 is started, the heating capacity of the heat pump refrigerant circuit 90 gradually increases as time elapses. As a result, in the first hot water / water mixing valve 16, the flow rate on the water / refrigerant heat exchangers 2 and 3 side gradually increases, and the flow rate on the hot water storage tank 21 side gradually decreases. If the user's desired temperature and amount of hot water are less than the heating capacity of the heat pump refrigerant circuit 90, when the temperature on the water refrigerant heat exchanger 2, 3 side reaches a predetermined temperature, the hot water from the hot water storage tank 21 side Supply is stopped and hot water is continuously supplied only from the heat pump refrigerant circuit 90 side.

  On the other hand, when the user's desired temperature and amount of hot water exceeds the heating capacity of the heat pump refrigerant circuit 90, hot water that has not reached the predetermined temperature is supplied from the water refrigerant heat exchangers 2 and 3, Hot water stored in the hot water storage tank 21 is mixed with this hot water, and hot water is supplied to the hot water supply terminal at the temperature and amount of hot water desired by the user. When the hot water stored in the hot water storage tank 21 is exhausted, the flow rate adjustment valve 18 reduces the flow rate to a flow rate that can be supplied by the heating capacity of the heat pump refrigerant circuit 90 while keeping the hot water supply temperature. In this state, hot water is continuously supplied from the heat pump refrigerant circuit 90 to the hot water supply terminal.

  When the hot water supply sensor 13 detects that the hot water supply terminal has been closed and the hot water temperature detected by the temperature sensor 65a of the hot water storage tank 21 is less than the set value, it is determined that the remaining hot water amount is small and the boil-back circuit 96 Use the to boil back. If the hot water temperature detected by the temperature sensor 65a of the hot water storage tank 21 is equal to or higher than the set value, it is determined that the remaining hot water amount is large, and the compressor 1 is stopped.

  In the present embodiment, the water supply flow rate sensor 13 detects that the hot water supply terminal has been opened, and the compressor 1 is started after 30 seconds. However, the start time of the compressor may be changed for each user. Further, this time may be changed depending on the use time zone. Further, the user's hot water supply pattern may be learned using learning control, and the start time of the compressor may be determined by statistically analyzing the cases where the hot water supply time is short and long.

The heat pump hot water supply apparatus 100 described in the present embodiment also has a bath automatic hot water filling function. When the user sets the bath temperature to 42 ° C., for example, using a remote controller (not shown) and turns on the bath hot water filling button, the hot water solenoid valve 31 of the bath water filling circuit 93 is opened. At this time, the water flowing in from the water supply fitting 11 due to the water supply pressure is supplied to the pressure reducing valve 12, the water supply flow rate sensor 13, the check valve 14, the water refrigerant heat exchanger flow rate sensor 15, the water refrigerant heat exchanger 2, and the first hot water mixing valve. 16, the second hot water / water mixing valve 17, the flow rate adjusting valve 18, the pouring solenoid valve 31, the flow switch 32, the bath circulation pump 33, the water level sensor 34, the hot water fitting 35, and the bath circulation adapter 36a, and heated and bathed. 36. In this automatic bath filling, the water supply flow rate sensor 13 detects the supply of clean water, but since the automatic bath filling button is ON, the control device automatically determines that the hot water supply time is long and supplies the water. The compressor 1 of the heat pump refrigerant circuit 90 is activated within 30 seconds after the flow sensor 13 detects the water flow.

  Here, the control device controls the opening degree of the flow rate adjusting valve 18 so that the flow rate of the feed water flow rate sensor 13 becomes a predetermined value. The temperature of the hot water until the heat pump refrigerant circuit 90 rises is lower than a predetermined target temperature set in the control device. Therefore, hot water heated by the water / refrigerant heat exchanger 2 and hot water of about 60 ° C. stored in the hot water storage tank 21 are mixed by the first hot water / water mixing valve 16, and the temperature detected by the mixing temperature sensor 63 becomes the target temperature. As described above, the control device controls the mixing amount in the first hot water mixing valve 16. Reheating or storing hot water in the hot water storage tank 21 is the same as after hot water supply from the hot water supply terminal. Further, the control circuit switches and controls each valve when the heat pump refrigerant circuit 90 is activated, similarly to the hot water supply from the hot water supply terminal.

  When the water level sensor 34 detects that the hot water in the bathtub 36 has reached a predetermined water level, the control device turns off the hot water solenoid valve 31. The remote control notifies you that bathing has been completed with a melody. At this time, if the hot water temperature of the temperature sensor 65 a attached to the hot water storage tank 21 is less than the set value, the control device determines that the remaining hot water amount is small, and performs a boil-back operation using the boil-back circuit 96. If the hot water temperature of the temperature sensor 65a is equal to or higher than the set value, the control device determines that the remaining hot water amount is large, and stops the compressor 1.

  As described above, according to the present embodiment, since the compressor can be started after a predetermined time has elapsed since the start of hot water supply, it is not necessary to start the heat pump refrigerant circuit when supplying hot water only for a short time, The operation time of start-up operation with low energy efficiency can be reduced. In addition, even if the amount of hot water discharged from the hot water storage tank increases and the tank hot water storage operation increases, the water refrigerant heat exchanger can be switched between parallel connection and series connection. Efficiency can be improved. Therefore, the energy efficiency of the heat pump water heater can be improved.

It is a circuit diagram of one Example of the heat pump hot-water supply apparatus which concerns on this invention. It is a circuit diagram of one Example of the heat pump hot-water supply apparatus which concerns on this invention. It is a figure explaining the hot water supply operation of the heat pump hot water supply apparatus shown in FIG. It is a figure explaining the hot water supply operation of the heat pump hot water supply apparatus shown in FIG. It is a table | surface which shows an example of the performance of the heat pump hot-water supply apparatus when changing hot-water supply temperature. It is a figure explaining the relationship between opening and closing of a hot water supply terminal, and the operation stop of a heat pump.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Compressor, 2, 3 ... Water refrigerant heat exchanger, 4 ... Expansion valve, 5 ... Evaporator, 13 ... Feed water flow sensor, 15 ... Water refrigerant heat exchanger flow sensor, 16 ... 1st hot water mixing valve, 17 2nd hot water / water mixing valve, 18 ... flow rate adjustment valve, 21 ... hot water storage tank, 31 ... pouring solenoid valve, 36 ... bathtub, 40a, 41a ... refrigerant side solenoid valve, 40b, 41b ... water side solenoid valve, 42a ... refrigerant Side check valve, 50 ... Water side check valve, 50 ... Discharge temperature sensor, 51 ... Discharge pressure sensor, 52 ... Evaporator refrigerant inlet temperature sensor, 53 ... Evaporator refrigerant outlet temperature sensor, 61 ... Water refrigerant heat exchanger Water inlet temperature sensor, 62 ... water refrigerant heat exchanger water outlet temperature sensor, 63 ... mixing temperature sensor, 64 ... hot water supply temperature sensor, 100 ... heat pump hot water supply device.

Claims (10)

In a heat pump water heater comprising a heat pump refrigerant circuit and a hot water storage tank for storing hot water heated by the heat pump refrigerant circuit, the heat pump refrigerant circuit includes two water refrigerant heat exchangers for exchanging heat between the refrigerant and water. A plurality of on-off valves that enable switching between a series connection and a parallel connection of the water flow paths and the refrigerant flow paths of the two water-refrigerant heat exchangers, and the on-off valves to a target temperature for heating in the heat pump refrigerant circuit. The two water refrigerant heat exchangers are connected in series when hot water is supplied at a high target temperature, and the two water refrigerant heat exchanges are provided when hot water is supplied at a low target temperature. A heat pump hot water supply device, characterized in that the appliances are connected in parallel.   When the control device operates the heat pump refrigerant circuit to supply hot water to the hot water storage tank, the two water refrigerant heat exchangers are connected in series, and the heat pump refrigerant circuit operates to supply hot water to the hot water supply terminal. The heat pump hot water supply apparatus according to claim 1, wherein the two water refrigerant heat exchangers are connected in parallel.   It has flow rate detection means for detecting the use of hot water supply at a hot water supply terminal connected to the heat pump hot water supply device, the control device can control the heat pump refrigerant circuit, and the flow rate detection means uses hot water supply at the hot water supply terminal. 3. The heat pump hot water supply apparatus according to claim 1, wherein the heat pump refrigerant circuit is controlled so that hot water is supplied only from the hot water storage tank until a predetermined time elapses after detection.   The control device controls the heat pump refrigerant circuit to be activated as soon as the flow rate detection means detects hot water when the hot water supply terminal is connected to the bathtub and fills the bathtub. The heat pump hot water supply apparatus according to claim 3. A heat pump refrigerant circuit having a water refrigerant heat exchanger for exchanging heat between the refrigerant compressed by the compressor and water; a hot water storage tank for storing hot water heated by the water refrigerant heat exchanger; the water refrigerant heat exchanger; In a heat pump hot water supply apparatus comprising a water supply means for supplying water to a hot water storage tank, and a hot water supply means for supplying hot water sent from the water refrigerant heat exchanger and the hot water storage tank, at least the refrigerant flow of the water refrigerant heat exchanger. A plurality of paths are formed, and the parallel connection and series connection of the plurality of formed refrigerant flow paths can be switched according to the target temperature of heating in the heat pump refrigerant circuit, and when hot water is supplied at a high target temperature, A heat pump hot water supply apparatus characterized in that when the refrigerant flow paths are connected in series and hot water is supplied at a low target temperature, the refrigerant flow paths are connected in parallel. When hot water is stored in the hot water storage tank, a plurality of formed refrigerant flow paths of the water refrigerant heat exchanger are connected in series, and when the heat pump refrigerant circuit is operated to supply hot water to the hot water supply terminal, the refrigerant flow The heat pump hot water supply apparatus according to claim 5, wherein the paths are connected in parallel. The heat pump hot water supply apparatus according to claim 5, further comprising a control unit that activates the compressor after a predetermined time has elapsed since the hot water supply was started. When there are a plurality of hot water supply means, one hot water supply means is connected to a bath, the other hot water supply means is connected to something other than a bath, and hot water is supplied from a hot water supply means connected to the bath 8. The heat pump hot water supply apparatus according to claim 7, wherein the control means can change the time for starting the compressor when hot water is supplied from a hot water supply means connected to a place other than the bath. In a heat pump water heater comprising a heat pump refrigerant circuit and a hot water storage tank for storing hot water heated by the heat pump refrigerant circuit, the heat pump refrigerant circuit includes two water refrigerant heat exchangers for exchanging heat between the refrigerant and water. A plurality of on-off valves that enable switching between serial connection and parallel connection of the two water refrigerant heat exchangers, and a control device that controls the on-off valves according to a target temperature of heating in the heat pump refrigerant circuit; When the hot water supply is performed at a high target temperature, the two water refrigerant heat exchangers are connected in series, and when the hot water supply is performed at a low target temperature, the two water refrigerant heat exchangers are connected in parallel. A device,
It has flow rate detection means for detecting the use of hot water supply at a hot water supply terminal connected to the heat pump hot water supply device, the control device can control the heat pump refrigerant circuit, and the flow rate detection means uses hot water supply at the hot water supply terminal. Until the predetermined time has passed since the detection, while controlling the heat pump refrigerant circuit to supply hot water only from the hot water storage tank,
The control device controls the heat pump refrigerant circuit to be activated as soon as the flow rate detection means detects hot water when the hot water supply terminal is connected to the bathtub and fills the bathtub. Heat pump water heater. A heat pump refrigerant circuit having a water refrigerant heat exchanger for exchanging heat between the refrigerant compressed by the compressor and water; a hot water storage tank for storing hot water heated by the water refrigerant heat exchanger; the water refrigerant heat exchanger; In a heat pump hot water supply apparatus comprising a water supply means for supplying water to a hot water storage tank, and a hot water supply means for supplying hot water sent from the water refrigerant heat exchanger and the hot water storage tank, at least a water flow path of the water refrigerant heat exchanger And a plurality of the refrigerant flow paths are formed, and the parallel connection and the series connection of the plurality of formed flow paths can be switched according to the target temperature of heating in the heat pump refrigerant circuit, and a high target temperature When supplying hot water with, the flow path is connected in series, and when supplying hot water at a low target temperature, a heat pump hot water supply apparatus with the flow path connected in parallel,
After a lapse of a predetermined time from the start of hot water supply, comprising a control means for starting the compressor,
When there are a plurality of hot water supply means, one hot water supply means is connected to a bath, the other hot water supply means is connected to something other than a bath, and hot water is supplied from a hot water supply means connected to the bath A heat pump hot water supply apparatus characterized in that the control means can change the time for starting the compressor when hot water is supplied from hot water supply means connected to other than the bath.

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