JP2023064884A - Hot water storage type hot water supply device - Google Patents

Abstract

To provide a hot water storage type hot water supply device capable of suppressing adverse influences caused by an excessive coolant in a case where an incoming water temperature rises, while avoiding additional installation of an apparatus.SOLUTION: A hot water storage type hot water supply device comprises: an air heat exchanger including a plurality of coolant passages; an inlet-side coolant valve provided at an inlet side of a partial coolant passage in the plurality of coolant passages of the air heat exchanger; an outlet-side coolant valve provided at an outlet side of the partial coolant passage; and control means for implementing hot water storage operation. The hot water storage type hot water supply device is capable of implementing first hot water storage operation in which the inlet-side coolant valve and the outlet-side coolant valve are opened and a coolant flows into the plurality of coolant passages of the air heat exchanger, and second hot water storage operation in which the inlet-side coolant valve and the outlet-side coolant valve are closed in a state where the coolant is encapsulated in the partial coolant passage of the air heat exchanger, and the coolant flows into the other coolant passages other than the partial coolant passage in the plurality of coolant passages of the air heat exchanger.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a hot water storage type hot water supply apparatus.

A heat pump water heater is disclosed in FIG. 2 of Patent Document 1 listed below. Reference numerals in Patent Document 1 are shown in parentheses below. In this heat pump water heater, the piping between the compressor (31) and the main hot water supply heat exchanger (32) is branched to include an on-off valve (50), an auxiliary heat exchanger (51) that exchanges heat with outside air, A sub-circuit is connected to the piping between the evaporator (34) and the compressor (31) through the sub-throttling device (52) in order. When the temperature of incoming water detected by the incoming water temperature sensor (53) for detecting the temperature of incoming water flowing into the heat exchanger (32) for main hot water supply rises above the temperature preset in the control device (54), the opening/closing is performed. Operate the valve (50) in the direction of opening. As a result, part of the high-temperature, high-pressure refrigerant discharged from the compressor (31) flows through the on-off valve (50) into the auxiliary heat exchanger (51). By operating the on-off valve (50) in the direction of opening, part of the high-temperature, high-pressure refrigerant discharged from the compressor (31) flows through the on-off valve (50) into the auxiliary heat exchanger (51). Since the refrigerant temperature is lowered and a large amount of refrigerant can be retained therein, the amount of refrigerant existing in the main circuit is reduced, and the discharge pressure and discharge temperature of the compressor (31) can be reduced.

JP 2005-300057 A

In the invention of Patent Document 1, it is necessary to additionally install a refrigerant pipe of the sub circuit, an on-off valve (50), an auxiliary heat exchanger (51), and a sub expansion device (52). Costs are likely to rise significantly. In addition, the additional installation of equipment tends to increase the size of the apparatus.

The present disclosure has been made to solve the above-described problems, and provides a hot water storage type hot water supply apparatus that can suppress the adverse effects of excess refrigerant when the temperature of incoming water rises while avoiding the installation of additional equipment. for the purpose.

A hot water storage type hot water supply apparatus according to the present disclosure includes a hot water storage tank, a compressor that compresses refrigerant, a water heat exchanger that exchanges heat between water and the refrigerant compressed by the compressor, and a water heat exchanger. an air heat exchanger having a plurality of refrigerant passages and exchanging heat between the air and the refrigerant decompressed by the decompressor; and a plurality of air heat exchangers An inlet-side refrigerant valve provided on the inlet side of some of the refrigerant passages, an outlet-side refrigerant valve provided on the outlet side of some of the refrigerant passages, and water heating the water flowing out of the hot water storage tank. and a control means for performing a hot water storage operation in which the hot water heated by the water heat exchanger flows into the hot water storage tank, the inlet side refrigerant valve and the outlet side refrigerant valve are opened, and the air heat exchanger The first hot water storage operation in which the refrigerant flows through the plurality of refrigerant passages, and the inlet side refrigerant valve and the outlet side refrigerant valve are closed with the refrigerant trapped in a part of the refrigerant passage of the air heat exchanger, and the air heat is exchanged. a second hot water storage operation in which the refrigerant flows through refrigerant passages other than some of the plurality of refrigerant passages of the device.

Advantageous Effects of Invention According to the present disclosure, it is possible to provide a hot water storage type hot water supply apparatus capable of suppressing the adverse effects of excess refrigerant when the temperature of incoming water rises while avoiding the installation of additional equipment.

1 is a diagram showing a hot water storage type hot water supply apparatus according to Embodiment 1. FIG. 4 is a perspective view showing another example of the air heat exchanger included in the hot water storage type hot water supply apparatus according to Embodiment 1. FIG. 4 is a flow chart relating to the operation of sealing the surplus refrigerant performed by the hot water storage type hot water supply apparatus according to Embodiment 1. FIG.

Embodiments will be described below with reference to the drawings. Elements that are common or correspond to each figure are denoted by the same reference numerals, and their explanations are simplified or omitted. In the following description, the terms "water", "hot water", and "hot water" basically mean liquid water, and can include cold water to hot water.

Embodiment 1.
FIG. 1 is a diagram showing a hot water storage type hot water supply apparatus according to Embodiment 1. FIG. As shown in FIG. 1 , hot water storage type hot water supply apparatus 1 according to the present embodiment includes heat pump unit 101 and hot water storage unit 102 . The heat pump unit 101 includes a compressor 107 , a water heat exchanger 106 , a pressure reducer 105 , an air heat exchanger 104 and an outdoor fan 103 . The heat pump unit 101 is installed outdoors.

Compressor 107 compresses the refrigerant. Water heat exchanger 106 heats water by exchanging heat between the water and the refrigerant compressed by compressor 107 . The pressure reducer 105 reduces the pressure of the refrigerant that has passed through the water heat exchanger 106 . The pressure reducer 105 may be, for example, an expansion valve or a capillary tube. The air heat exchanger 104 exchanges heat between the outdoor air and the refrigerant decompressed by the decompressor 105, thereby causing the refrigerant to absorb the heat of the outdoor air. The outdoor fan 103 blows outdoor air to the air heat exchanger 104 .

The air heat exchanger 104 has multiple refrigerant passages 111 . In the example of FIG. 1, air heat exchanger 104 has four refrigerant passages 111 . FIG. 2 is a perspective view showing another example of air heat exchanger 104 included in hot water storage type hot water supply apparatus 1 according to Embodiment 1. As shown in FIG. In the example of FIG. 2, air heat exchanger 104 has six refrigerant passages 111 .

An inlet-side refrigerant valve 110 is provided on the inlet side of some of the plurality of refrigerant passages 111 of the air heat exchanger 104 . The part of the refrigerant passage 111 may be hereinafter referred to as a "refrigerant sealing passage 120". In the illustrated example, the number of refrigerant sealing passages 120 is one. That is, one of the plurality of refrigerant passages 111 of the air heat exchanger 104 corresponds to the refrigerant sealing passage 120 . An outlet-side refrigerant valve 121 is provided on the outlet side of the refrigerant sealing passage 120 .

A liquid header 109 is provided at the refrigerant inlet of the air heat exchanger 104 . A refrigerant pipe 122 connects the outlet of the pressure reducer 105 to the inlet of the liquid header 109 . Each inlet side of the plurality of refrigerant passages 111 is connected to the liquid header 109 . An inlet side refrigerant valve 110 is provided in the refrigerant sealing passage 120 between the liquid header 109 and the air heat exchanger 104 .

A gas header 119 is provided at the refrigerant outlet of the air heat exchanger 104 . Each outlet side of the plurality of refrigerant passages 111 is connected to a gas header 119 . An outlet-side refrigerant valve 121 is provided in the refrigerant sealing passage 120 between the air heat exchanger 104 and the gas header 119 .

As shown in FIG. 1, refrigerant pipe 123 connects the outlet of gas header 119 to the inlet of compressor 107 . The hot water storage unit 102 includes a hot water storage tank 108 , a branch valve 112 , a hot water supply temperature adjusting mixing valve 113 , a pressure reducing valve 114 , a tank bottom temperature sensor 115 and a circulation pump 118 .

Inside the hot water storage tank 108, a temperature stratification is formed in which the upper side has a high temperature and the lower side has a low temperature due to the difference in water density according to the temperature. Hot water storage tank 108 in the present embodiment is composed of a single container. As a modification, the hot water storage tank 108 may have a structure in which a plurality of containers are connected in series via pipes. In the plurality of containers, the lower part of the container on the upper layer side of the temperature stratification, ie, the high temperature side, communicates with the upper part of the container on the lower layer side of the temperature stratification, ie, the low temperature side, by a pipe.

A water supply pipe 124 is connected to the lower portion of the hot water storage tank 108 . For example, water supplied from a water source such as tap water flows into the hot water storage tank 108 through the water supply pipe 124, so that the inside of the hot water storage tank 108 is maintained in a full water state. A pressure reducing valve 114 provided in the water supply pipe 124 reduces the water pressure from the water source to a predetermined pressure.

The tank bottom temperature sensor 115 is installed at the bottom of the hot water storage tank 108 . A tank bottom temperature sensor 115 detects the water temperature at the bottom of the hot water storage tank 108 . In the present disclosure, the water temperature before being heated by the water heat exchanger 106 is referred to as "pre-heating temperature." The tank bottom temperature sensor 115 corresponds to pre-heating temperature detection means for detecting the pre-heating temperature.

A water channel 125 connects the lower part of the hot water storage tank 108 to the water inlet of the water heat exchanger 106 . A circulation pump 118 is connected in the middle of the water channel 125 . A water line 126 connects the hot water outlet of the water heat exchanger 106 to the inlet of the branch valve 112 . A first outlet of the branch valve 112 is connected to the top of the hot water tank 108 . A second outlet of the branch valve 112 communicates with a first inlet of the hot water supply temperature adjusting mixing valve 113 . A first inlet of hot water supply temperature adjusting mixing valve 113 also communicates with the upper portion of hot water storage tank 108 . The water supply pipe 127 branches from the water supply pipe 124 on the downstream side of the pressure reducing valve 114 and is connected to the second inlet of the hot water supply temperature adjusting mixing valve 113 . A hot water supply pipe 128 is connected to the outlet of the hot water supply temperature adjusting mixing valve 113 .

The hot water storage type hot water supply apparatus 1 includes a control means 130 that controls the operation of the hot water storage type hot water supply apparatus 1 . The control means 130 can carry out the hot water storage operation. The hot water storage operation is an operation in which the water flowing out of the hot water storage tank 108 flows into the water heat exchanger 106 and the hot water heated by the water heat exchanger 106 flows into the hot water storage tank 108 . The control means 130 in the present embodiment includes a valve control section 116 that sends signals to the inlet-side refrigerant valve 110 and the outlet-side refrigerant valve 121, and a calculation section that determines the opening degrees of the inlet-side refrigerant valve 110 and the outlet-side refrigerant valve 121. 117.

During the hot water storage operation, the operation is as follows. Compressor 107 and circulation pump 118 are driven. The water flowing out from the lower part of the hot water storage tank 108 flows into the water heat exchanger 106 through the water channel 125 and the circulation pump 118 . The high-temperature and high-pressure refrigerant compressed by the compressor 107 flows into the water heat exchanger 106 . The refrigerant exchanges heat with water in the water heat exchanger 106 to generate hot water. The hot water flows from the water heat exchanger 106 into the upper part of the hot water storage tank 108 through the water channel 126 and the branch valve 112 . During the hot water storage operation, the temperature boundary layer between the hot water on the upper side in the hot water storage tank 108 and the water on the lower side in the hot water storage tank 108 gradually moves downward.

The high-pressure refrigerant that has passed through the water heat exchanger 106 is decompressed by the decompressor 105 to become low-pressure refrigerant. Low-pressure refrigerant is distributed through the liquid header 109 to each of the plurality of refrigerant passages 111 of the air heat exchanger 104 . In the air heat exchanger 104, the low-pressure refrigerant exchanges heat with the outside air sent by the outdoor fan 103 to evaporate. The low-pressure refrigerant gas that has flowed out of the air heat exchanger 104 flows through the gas header 119 and refrigerant pipes 123 into the compressor 107 .

The downstream side of hot water supply pipe 128 is connected to a hot water supply destination. The hot water supply destination may be, for example, a bathtub, a shower, a sink faucet, a washbasin faucet, or the like. When hot water is supplied to the hot water supply destination, the hot water flowing out from the upper part of the hot water storage tank 108 flows into the first inlet of the hot water supply temperature adjusting mixing valve 113, and the water in the water supply pipe 127 flows into the second inlet of the hot water supply temperature adjusting mixing valve 113. flow into the entrance. Hot water supply temperature adjusting mixing valve 113 mixes the hot water flowing in from the first inlet and the water flowing in from the second inlet, and causes the mixture to flow into hot water supply pipe 128 . When the opening degree of the hot water supply temperature adjusting mixing valve 113 is adjusted, the mixing ratio between the hot water flowing in from the first inlet and the water flowing in from the second inlet changes, thereby changing the temperature of the hot water flowing out to the hot water supply pipe 128. . The control means 130 controls the operation of the hot water supply temperature adjusting mixing valve 113 so that the temperature of the hot water passing through the hot water supply pipe 128 becomes equal to the set temperature.

The temperature of the hot water flowing out of the water heat exchanger 106 during the hot water storage operation is called the boiling temperature. During the hot water storage operation, the control means 130 may adjust the rotation speed of the circulation pump 118 so that the boiling temperature becomes equal to the target value. The boiling temperature may be, for example, a relatively high temperature of about 60°C to 80°C, but is preferably a relatively low temperature of, for example, about 50°C to 60°C. This is because the lower the boiling temperature, the lower the discharge temperature of the compressor, so that the input energy of the compressor 107 can be reduced, and the power consumption can be suppressed.

In the present disclosure, storing hot water with a relatively high boiling temperature in the hot water storage tank 108 is referred to as "high temperature storage", and storing hot water with a relatively low boiling temperature in the hot water storage tank 108 is referred to as "low temperature storage". Also, the temperature of the water flowing into the water heat exchanger 106 is called "inlet water temperature". Also, the temperature of the refrigerant flowing out of the water heat exchanger 106 is called "outlet refrigerant temperature". Also, the amount of heat exchanged between the water and the refrigerant in the water heat exchanger 106 is referred to as "water-refrigerant heat exchange amount". Also, the pressure on the high pressure side of the refrigerant circuit is referred to as "high pressure side refrigerant pressure". The high pressure side refrigerant pressure corresponds to the pressure of the refrigerant inside the water heat exchanger 106 .

In order to store the same amount of heat in the hot water storage tank 108 as in the case of high temperature storage, the volume of hot water stored in the hot water storage tank 108 must be larger than in the case of high temperature storage. Therefore, in the case of low-temperature hot water storage, it is necessary to store hot water up to the lower portion of the hot water storage tank 108 . Therefore, in the case of low-temperature hot water storage, the water temperature in the lower part of hot water storage tank 108 tends to be higher at the end of the hot water storage operation than at the start of the hot water storage operation. As the water temperature in the lower part of the hot water storage tank 108 rises, the incoming water temperature rises. When the incoming water temperature rises, the outlet refrigerant temperature of the water heat exchanger 106 rises, and the water-refrigerant heat exchange amount of the water heat exchanger 106 decreases. When the amount of water-refrigerant heat exchange in the water heat exchanger 106 decreases, the amount of refrigerant required by the refrigerant circuit decreases, resulting in surplus refrigerant in the refrigerant circuit.

The hot water storage type hot water supply apparatus 1 of the present embodiment can perform a first hot water storage operation and a second hot water storage operation as the hot water storage operation. The first hot water storage operation is an operation in which the inlet-side refrigerant valve 110 and the outlet-side refrigerant valve 121 are opened and refrigerant flows through all of the plurality of refrigerant passages 111 of the air heat exchanger 104 . During the first hot water storage operation, the control means 130 opens the inlet side refrigerant valve 110 and the outlet side refrigerant valve 121 . The first hot water storage operation corresponds to a normal hot water storage operation.

In the second hot water storage operation, the inlet-side refrigerant valve 110 and the outlet-side refrigerant valve 121 are closed with excess refrigerant trapped in the refrigerant sealing passage 120 of the air heat exchanger 104, and the plurality of air heat exchangers 104 are closed. This is an operation in which the refrigerant flows through the refrigerant passages 111 other than the refrigerant sealing passage 120 among the refrigerant passages 111 . During the first hot water storage operation, the control means 130 closes the inlet-side refrigerant valve 110 and the outlet-side refrigerant valve 121 .

In the present embodiment, when the incoming water temperature is high, the amount of refrigerant circulating in the refrigerant circuit is adjusted to an appropriate amount by executing the second hot water storage operation in which the surplus refrigerant is confined in the refrigerant sealing passage 120. becomes possible. Therefore, it is possible to reliably suppress an increase in the pressure of the high-pressure side refrigerant due to the influence of the surplus refrigerant, and it is possible to perform hot water storage operation while suppressing a decrease in energy efficiency. Moreover, since the surplus refrigerant is stored in the refrigerant sealing passage 120 in the air heat exchanger 104, which is an existing device, there is no need to additionally provide a reservoir for storing the surplus refrigerant. Therefore, the number of devices installed in the heat pump unit 101 can be reduced, the manufacturing cost can be suppressed, and the hot water storage type hot water supply apparatus 1 can be provided at a low price. Since the size of the heat pump unit 101 does not increase, the installation location of the heat pump unit 101 is less restricted.

In the present embodiment, when performing the second hot water storage operation, the control means 130 operates the inlet side refrigerant valve 110 and the outlet side refrigerant valve 121 according to the pre-heating temperature detected by the tank lower portion temperature sensor 115. . Since the water flowing out from the lower part of the hot water storage tank 108 flows into the water heat exchanger 106, the temperature before heating detected by the tank lower part temperature sensor 115 before starting the hot water storage operation is equal to the incoming water temperature after the hot water storage operation is started. It can be assumed that they are approximately equal. That is, before starting the second hot water storage operation, the temperature of the incoming water can be predicted by the tank bottom temperature sensor 115 . Therefore, when performing the second hot water storage operation, the inlet side refrigerant valve 110 and the outlet side refrigerant valve 121 are operated according to the pre-heating temperature detected by the tank bottom temperature sensor 115, thereby performing the second hot water storage operation. It becomes possible to implement it more appropriately.

In the present embodiment, control means 130 performs the first hot water storage operation when the preheating temperature is lower than the reference, and performs the second hot water storage operation when the preheating temperature is higher than the reference. This makes it possible to properly use the first hot water storage operation and the second hot water storage operation. Before starting the hot water storage operation, the control means 130 determines whether to perform the first hot water storage operation or the second hot water storage operation according to the pre-heating temperature detected by the tank bottom temperature sensor 115. good.

In the present embodiment, the control means 130 operates the compressor 107 before performing the second hot water storage operation to move the refrigerant from the water heat exchanger 106 into the refrigerant sealing passage 120 of the air heat exchanger 104. Carry out the surplus refrigerant sealing operation to be moved. The operating speed of the compressor 107 during the surplus refrigerant sealing operation may be lower than the operating speed of the compressor 107 during the hot water storage operation. During the excessive refrigerant sealing operation, the control means 130 may fully open the pressure reducer 105 . During the surplus refrigerant sealing operation, after the liquid refrigerant in the water heat exchanger 106 moves into the refrigerant sealing passage 120, the control means 130 closes the inlet side refrigerant valve 110 and the outlet side refrigerant valve 121 to Liquid refrigerant may be confined within the sealing passage 120 . By performing the surplus refrigerant sealing operation before performing the second hot water storage operation, it is possible to reliably confine the surplus refrigerant in the refrigerant sealing passage 120 .

In the surplus refrigerant sealing operation, the control means 130 may adjust the amount of refrigerant confined in the refrigerant sealing passage 120 of the air heat exchanger 104 according to the pre-heating temperature. For example, the control means 130 may increase the amount of refrigerant confined in the refrigerant sealing passage 120 in the excess refrigerant sealing operation as the pre-heating temperature increases. The higher the incoming water temperature, the more excess refrigerant is generated. Therefore, the higher the temperature before heating, the more the amount of refrigerant confined in the refrigerant sealing passage 120, thereby making the amount of refrigerant circulating in the refrigerant circuit during the second hot water storage operation more appropriate. becomes possible.

As described above, in the illustrated example, the number of refrigerant sealing passages 120 is one. In the present disclosure, the number of refrigerant sealing passages 120 may be two or more. That is, when N is an integer of 2 or more and M is an integer larger than N, the air heat exchanger 104 has M refrigerant passages 111, and among the M refrigerant passages 111 , the N refrigerant passages 111 may serve as the passages 120 for sealing the refrigerant. When the number of refrigerant sealing passages 120 is two or more, it is possible to confine a larger amount of surplus refrigerant in the refrigerant sealing passages 120 than when the number of refrigerant sealing passages 120 is one. When the air heat exchanger 104 has N refrigerant-sealing passages 120, N inlet-side refrigerant valves 110 and N outlet-side refrigerant valves 121 are provided corresponding to the N refrigerant-sealing passages 120. may be provided. By doing so, it is possible to easily increase the number of the refrigerant sealing passages 120 .

A plurality of models of hot water storage type hot water supply apparatuses 1 with different amounts of refrigerant filled in the refrigerant circuit may be produced. The larger the amount of refrigerant charged in the refrigerant circuit of the model, the larger the amount of surplus refrigerant generated when the temperature of incoming water is high. According to the present disclosure, by increasing the number of the refrigerant sealing passages 120, it is possible to appropriately cope with a model with a large amount of refrigerant filled in the refrigerant circuit, that is, a model with a large amount of surplus refrigerant. becomes.

The calculation unit 117 of the control means 130 determines the valve opening degree of the inlet side refrigerant valve 110 and the valve opening of the outlet side refrigerant valve 121 at the time of the surplus refrigerant sealing operation according to the pre-heating temperature detected by the tank bottom temperature sensor 115. You can calculate degrees. The valve control unit 116 of the control unit 130 transmits information on the valve opening degree calculated by the calculation unit 117 to the inlet-side refrigerant valve 110 and the outlet-side refrigerant valve 121, thereby controlling the inlet-side refrigerant valve 110 and the outlet-side refrigerant valve. 121 may be controlled.

The calculation unit 117 may calculate the water-refrigerant heat exchange amount of the water heat exchanger 106 according to the pre-heating temperature detected by the tank bottom temperature sensor 115 . The calculation unit 117 calculates the water-refrigerant heat exchange amount of the water heat exchanger 106 in the steady state, which is the state before the incoming water temperature rises, and the water-refrigerant heat exchange amount of the water heat exchanger 106 when the incoming water temperature rises. A ratio to the amount of heat exchange may be calculated. The ratio is called "heat exchange amount ratio". The calculation unit 117 calculates the required sealed refrigerant amount, which is the amount of refrigerant confined in the refrigerant sealing passage 120, from the amount of refrigerant existing in the water heat exchanger 106 in the steady state and the heat exchange amount ratio. may In the surplus refrigerant sealing operation, the valve control unit 116 sends a signal for controlling the degree of opening of the inlet side refrigerant valve so that the amount of refrigerant corresponding to the calculated required amount of refrigerant to be sealed is confined in the refrigerant sealing passage 120. 110 and outlet side refrigerant valve 121 . The control means 130 can estimate the moving speed or mass flow rate of the liquid refrigerant from the water heat exchanger 106 to the refrigerant sealing passage 120 according to the operating speed of the compressor 107 . In the surplus refrigerant sealing operation, the control means 130 operates the compressor 107 with the inlet side refrigerant valve 110 open and the outlet side refrigerant valve 121 closed, and the liquid refrigerant from the water heat exchanger 106 is used for refrigerant sealing. It may flow into passageway 120 . The control means 130 calculates the amount of refrigerant flowing into the refrigerant sealing passage 120 according to the movement speed or mass flow rate of the liquid refrigerant, and when the amount of refrigerant flowing into the refrigerant sealing passage 120 reaches the required amount of refrigerant to be sealed. Then, the inlet side refrigerant valve 110 may be closed to end the surplus refrigerant sealing operation.

FIG. 3 is a flowchart relating to the surplus refrigerant sealing operation performed by the hot water storage type hot water supply apparatus 1 according to the first embodiment. In step S1 of FIG. 3, the control means 130 calculates the water-refrigerant heat exchange amount of the water heat exchanger 106 in the steady state, which is the state before the incoming water temperature rises. For example, the control means 130 calculates the water-refrigerant heat exchange amount of the water heat exchanger 106 in the steady state based on the compressor discharge temperature, the inlet water temperature, the high-pressure side refrigerant pressure, and the refrigerant flow rate. may

Proceeding from step S1 to step S2, the control means 130 compares the pre-heating temperature detected by the tank bottom temperature sensor 115 with the reference temperature. The reference temperature value may be, for example, a value within the range of 30°C to 50°C. When the pre-heating temperature is equal to or lower than the reference temperature, the first hot water storage operation is performed instead of the second hot water storage operation, so there is no need to perform the surplus refrigerant sealing operation. If the pre-heating temperature is equal to or lower than the reference temperature, the control means 130 executes the process of step S2 again. When the temperature before heating is higher than the reference temperature, the process proceeds from step S2 to step S3.

At step S3, the control means 130 determines whether or not there is a request to perform the hot water storage operation. For example, when the amount of stored heat detected by a stored hot water temperature sensor (not shown) for detecting the amount of stored heat in the hot water storage tank 108 falls below a predetermined amount of heat set in preparation for the hot water supply load, a request to perform the hot water storage operation is issued. served. If a request to perform the hot water storage operation has not been issued, the control means 130 returns from step S3 to step S2 and executes the process of step S2 again.

If there is a request to perform the hot water storage operation in step S3, the control means 130 proceeds to step S4 and performs the surplus refrigerant sealing operation prior to performing the second hot water storage operation. In the surplus refrigerant sealing operation in step S4, as described above, the control unit 130 causes the calculation unit 117 to determine the necessary The amount of refrigerant to be sealed is calculated, and the amount of refrigerant flowing into the refrigerant sealing passage 120 is calculated according to the moving speed or mass flow rate of the liquid refrigerant corresponding to the operating speed of the compressor 107, and the opening degree of the inlet side refrigerant valve 110 is calculated. The amount of refrigerant confined in the refrigerant sealing passage 120 may be adjusted by adjusting the opening degree of the outlet-side refrigerant valve 121 . After the surplus refrigerant sealing operation is finished, the control means 130 performs the second hot water storage operation.

In the present disclosure, the pre-heating temperature detection means is not limited to the tank bottom temperature sensor 115 . In the present disclosure, a pre-heating temperature sensing means may be placed in the passage of water entering the water heat exchanger 106 . For example, an inlet water temperature sensor arranged near the water inlet of the water heat exchanger 106 may be used as the pre-heating temperature detection means. When the distance from the outlet of the hot water storage tank 108 to which the water channel 125 is connected to the water inlet of the water heat exchanger 106 is long, heat is dissipated from the water channel 125 to the surroundings, causing the tank bottom temperature sensor 115 to detect the temperature. There may be a large difference between the temperature and the actual incoming water temperature. In such a case, by using an incoming water temperature sensor arranged near the water inlet of the water heat exchanger 106 as pre-heating temperature detection means, the second hot water storage operation and the surplus refrigerant sealing operation can be performed more appropriately.

In the present disclosure, the control means may be configured as follows. Each function of the control means may be accomplished by a processing circuit. The processing circuitry of the control means may comprise at least one processor and at least one memory. When the processing circuit comprises at least one processor and at least one memory, each function of the control means may be achieved by software, firmware or a combination of software and firmware. At least one of software and firmware may be written as a program. Software and/or firmware may be stored in the at least one memory. At least one processor may accomplish each function of the control means by reading and executing a program stored in at least one memory. The at least one memory may include non-volatile or volatile semiconductor memory, magnetic disks, or the like.

The processing circuitry of the control means may comprise at least one piece of dedicated hardware. If the processing circuit comprises at least one piece of dedicated hardware, the processing circuit may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field- Programmable Gate Array), or a combination thereof. The functions of each part of the control means may be accomplished respectively by processing circuitry. Also, the functions of each section of the control means may be collectively achieved by a processing circuit. For each function of the control means, a part may be achieved by dedicated hardware and another part may be achieved by software or firmware. The processing circuitry may accomplish each function of the control means by means of hardware, software, firmware, or a combination thereof.

The configuration is not limited to a configuration in which the operation is controlled by a single control means, and may be a configuration in which a plurality of control means cooperate to control the operation.

1 hot water storage type hot water supply device 101 heat pump unit 102 hot water storage unit 103 outdoor fan 104 air heat exchanger 105 pressure reducer 106 water heat exchanger 107 compressor 108 hot water storage tank 109 liquid header 110 inlet side refrigerant Valve 111 Refrigerant passage 112 Branch valve 113 Mixing valve for hot water supply temperature adjustment 114 Pressure reducing valve 115 Tank lower part temperature sensor 116 Valve control unit 117 Operation unit 118 Circulation pump 119 Gas header 120 Refrigerant sealing passage , 121 outlet-side refrigerant valve, 122 refrigerant pipe, 123 refrigerant pipe, 124 water supply pipe, 125 water channel, 126 water channel, 127 water supply pipe, 128 hot water supply pipe, 130 control means

Claims (7)

a water storage tank;
a compressor that compresses a refrigerant;
a water heat exchanger that exchanges heat between water and the refrigerant compressed by the compressor;
a decompressor that decompresses the refrigerant that has passed through the water heat exchanger;
an air heat exchanger that has a plurality of refrigerant passages and exchanges heat between air and the refrigerant decompressed by the decompressor;
an inlet-side refrigerant valve provided on an inlet side of some of the plurality of refrigerant passages of the air heat exchanger;
an outlet-side refrigerant valve provided on the outlet side of the part of the refrigerant passage;
a control means for performing a hot water storage operation in which the water flowing out of the hot water storage tank flows into the water heat exchanger and the hot water heated by the water heat exchanger flows into the hot water storage tank;
with
a first hot water storage operation in which the inlet-side refrigerant valve and the outlet-side refrigerant valve are opened and the refrigerant flows through the plurality of refrigerant passages of the air heat exchanger;
The inlet-side refrigerant valve and the outlet-side refrigerant valve are closed with the refrigerant confined in the part of the refrigerant passage of the air heat exchanger, and one of the plurality of refrigerant passages of the air heat exchanger is a second hot water storage operation in which the refrigerant flows through refrigerant passages other than the part of the refrigerant passages of
A hot water storage type hot water supply device capable of implementing Pre-heating temperature detection means for detecting a pre-heating temperature, which is the water temperature before being heated by the water heat exchanger,
2. The hot water storage type hot water supply apparatus according to claim 1, wherein said control means operates said inlet side refrigerant valve and said outlet side refrigerant valve according to said pre-heating temperature. Pre-heating temperature detection means for detecting a pre-heating temperature, which is the water temperature before being heated by the water heat exchanger,
The first hot water storage operation is performed when the pre-heating temperature is lower than the reference, and the second hot water storage operation is performed when the pre-heating temperature is higher than the reference. The hot water storage type hot water supply device described. The control means moves the refrigerant from the water heat exchanger into the portion of the refrigerant passage of the air heat exchanger by operating the compressor before performing the second hot water storage operation. The hot water storage type hot water supply apparatus according to any one of claims 1 to 3, wherein a refrigerant sealing operation is performed. Pre-heating temperature detection means for detecting a pre-heating temperature, which is the water temperature before being heated by the water heat exchanger,
5. The hot water storage type according to claim 4, wherein in the surplus refrigerant sealing operation, the control means adjusts the amount of the refrigerant confined in the part of the refrigerant passage of the air heat exchanger according to the pre-heating temperature. water heater. The hot water storage type hot water supply apparatus according to any one of claims 1 to 5, wherein the number of refrigerant passages in the part of the air heat exchanger is two or more. 6. The hot water storage type hot water supply apparatus according to any one of claims 2, 3 and 5, wherein the pre-heating temperature detecting means is arranged in a passage of water flowing into the water heat exchanger.

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