JP2021001718A - Heat pump type hot water heating system - Google Patents

Abstract

To provide a heat pump type hot water heating system preventing deterioration of indoor comfort during a heating operation while shortening a defrosting time.SOLUTION: During a heating operation, when a temperature of hot water supplied to a heat exchange terminal in operation out of a plurality of heat exchange terminals reaches a set temperature level, a flow control valve corresponding to at least one of stopped heat exchange terminals is opened to perform a heat accumulation operation for causing the hot water to flow in the stopped heat exchange terminal to accumulate heat. During a defrosting operation of an air heat exchanger of a heat pump type heat source machine, a flow control valve corresponding to the heat exchange terminal in operation out of the plurality heat exchange terminals is closed and the flow control valve corresponding to the stopped heat exchange terminal that has accumulated heat during the heat accumulation operation out of the plurality of the heat exchange terminals is opened. Therefore, during the defrosting operation, this configuration enables slow reduction of a room temperature of an air-conditioned space corresponding to the heat exchange terminal in operation, and enables the heat accumulated in the stopped heat exchange terminal to be used for defrosting so as to shorten a defrosting time.SELECTED DRAWING: Figure 7

Description

The present invention relates to a heat pump type hot water heating system capable of performing hot water heating.

Conventionally, in this type of equipment, when multiple heat exchange terminals (for example, floor heating panels) are installed indoors, it is necessary to defrost the air heat exchanger of the heat pump type heat source machine during heating operation. Among the plurality of heat exchange terminals, the heat valve corresponding to the operating heat exchange terminal is closed, and among the plurality of heat exchange terminals, the heat valve corresponding to the stopped heat exchange terminal is opened. (See, for example, Patent Document 1.)

When the air heat exchanger is defrosted, the circulation direction of the refrigerant is reversed, the air heat exchanger becomes a condenser, the liquid refrigerant heat exchanger becomes an evaporator, and the liquid refrigerant heat exchanger becomes low temperature during defrosting. However, in this conventional one, the heat valve corresponding to the heat exchange terminal during the heating operation is closed at the time of defrosting, and the heat valve corresponding to the stopped heat exchange terminal is opened to perform the heating operation. Since cold water with a low temperature does not flow to the heat exchange terminal inside, the temperature drop in the room during heating is suppressed and comfort is improved, while cold water with a low temperature flows to the heat exchange terminal that is stopped. As a result, the stopped heat exchange terminal absorbs heat from the corresponding room and uses the heat to defrost the air heat exchanger.

Japanese Unexamined Patent Publication No. 2016-20302

By the way, in this conventional one, during the defrosting operation, the heat valve corresponding to the stopped heat exchange terminal is opened to allow cold water to flow, but the room where the heating operation is not performed is of course cold. Even if cold water is passed through the stopped heat exchange terminal, the amount of heat that can be absorbed from the room corresponding to the stopped heat exchange terminal is very small, and the heat required for defrosting the air heat exchanger cannot be removed, so defrosting operation However, there is a problem that it takes a long time, and the heating operation cannot be returned until the defrosting is completed, and the hot water cannot be supplied to the room during the heating operation for a long time, which may impair the comfort.

Therefore, an object of the present invention is to provide a heat pump type hot water heating system that does not impair the comfort of the room during the heating operation while shortening the defrosting time.

In order to solve the above problems, in claim 1, the present invention includes a compressor for compressing a refrigerant, a liquid refrigerant heat exchanger for heat exchange between a circulating liquid and the refrigerant, a decompression means, and an air heat exchanger. Corresponds to the heat pump type heat source machine having the above, the liquid refrigerant heat exchanger of the heat pump type heat source machine, a plurality of heat exchange terminals that heat the air-conditioned space using the circulating liquid as a heat source, and the plurality of heat exchange terminals. The temperature level of the circulating fluid supplied to the heat exchange terminal and the circulating circuit formed by connecting the individual flow control valves to the circulating fluid and the circulating pump for circulating the circulating fluid with a pipe. The setting means for setting and the control unit that controls the heat pump type heat source machine and the flow control valve to perform the heating operation so that the temperature of the circulating liquid supplied to the heat exchange terminal becomes the temperature level. In the heat pump type hot water heating system provided, when the temperature of the circulating fluid supplied to the heat exchange terminal being operated among the plurality of heat exchange terminals reaches the temperature level during the heating operation, the said A heat storage control means for performing a heat storage operation in which the flow control valve corresponding to at least one of the stopped heat exchange terminals among the plurality of heat exchange terminals is opened and the circulating liquid is allowed to flow through the stopped heat exchange terminals to store heat. During the defrosting operation of the air heat exchanger of the heat pump type heat source machine, the flow control valve corresponding to the heat exchange terminal being operated is closed among the plurality of heat exchange terminals, and the heat exchange terminals of the plurality of heat exchange terminals are closed. A defrost control means for opening the flow control valve corresponding to the stopped heat exchange terminal in which the heat storage operation was performed was provided.

Further, in claim 2, the heat storage control means stores in advance heat storage preparation conditions set based on the outside air temperature and the refrigerant temperature of the air heat exchanger, and operates in the plurality of heat exchange terminals. When the temperature of the circulating fluid supplied to the heat exchange terminal inside reaches the temperature level and the heat storage preparation conditions are satisfied, the heat storage operation is performed.

Further, in claim 3, in the heat storage control means, the temperature of the circulating fluid supplied to the operating heat exchange terminal among the plurality of heat exchange terminals reaches the temperature level, and the compressor The heat storage operation is performed when the number of rotations of

Further, in claim 4, the heat storage control means stores in advance heat storage preparation conditions set based on the outside air temperature and the refrigerant temperature of the air heat exchanger, and operates in the plurality of heat exchange terminals. When the temperature of the circulating fluid supplied to the heat exchange terminal inside reaches the temperature level, the rotation speed of the compressor is equal to or less than the predetermined rotation speed, and the heat storage preparation condition is satisfied, the heat storage operation is performed. Was supposed to be done.

Further, according to claim 5, during the heat storage operation, the temperature level of the circulating fluid supplied to the stopped heat exchange terminal among the plurality of heat exchange terminals can be set during the normal heating operation. It was assumed to be set lower than the temperature level.

Further, in claim 6, the heat storage control means closes the flow control valve corresponding to the stopped heat exchange terminal after a certain time has elapsed from the start of the heat storage operation.

According to claim 1 of the present invention, the circulating fluid is circulated only to the operating heat exchange terminal until the temperature of the circulating fluid supplied to the operating heat exchange terminal reaches the temperature level, and the circulating fluid is circulated only to the operating heat exchange terminal during operation. The air-conditioned space corresponding to the heat exchange terminal can be quickly heated. Further, when the temperature of the circulating fluid supplied to the heat exchange terminal during operation reaches the set temperature level, that is, the load on the air-conditioned space corresponding to the heat exchange terminal during operation is reduced, and the air-conditioned space is reduced. When the room temperature becomes stable, the flow control valve corresponding to the stopped heat exchange terminal is also opened and the circulating fluid flows there, so that the room temperature of the air-conditioned space corresponding to the operating heat exchange terminal is reached. Heat for defrosting can be stored in the stopped heat exchange terminal while maintaining a stable state. During the defrosting operation, the flow control valve corresponding to the heat exchange terminal during operation is closed, so that the circulating fluid whose temperature has dropped due to the defrosting operation does not flow to the heat exchange terminal during operation. The temperature drop of the air-conditioned space corresponding to the heat exchange terminal inside can be moderated, and the comfort is not impaired. On the other hand, the heat exchange during the stoppage that has stored heat during the heat storage operation Since the flow control valve corresponding to the terminal is opened and the circulating liquid in the heat exchange terminal is circulated, the retained heat held by the circulating liquid is pumped up to the refrigerant side for defrosting by the liquid refrigerant heat exchanger. , The temperature of the refrigerant can be raised, and the defrosting operation time when defrosting the air heat exchanger can be shortened.

Further, according to claim 2, the heat storage preparation conditions presumed to start the defrosting operation directly from the outside air temperature and the refrigerant temperature of the air heat exchanger are stored in advance, and the heat exchange during the operation is performed. When the temperature of the circulating fluid supplied to the terminal reaches the set temperature level and the heat storage preparation condition is satisfied, the heat storage operation is performed, so that the heat storage operation is performed immediately before the defrosting operation is started. It can be operated, and the heat stored in the stopped heat exchange terminal before the defrosting operation is started is less time to be wasted, and much of the stored heat is defrosted in the air heat exchanger. Can be used for.

Further, according to claim 3, the load on the air-conditioned space corresponding to the heat exchange terminal during operation is large, and the temperature of the circulating fluid supplied to the heat exchange terminal during operation can be raised to a set temperature level. However, when the space to be air-conditioned is full to heat and the output of the compressor is not so large, that is, when the rotation speed of the compressor is higher than the predetermined rotation speed, the heat storage operation is not performed. When the comfort is maintained by devoting itself to heating the air-conditioned space corresponding to the heat exchange terminal during operation and there is a margin in the output of the compressor, that is, when the rotation speed of the compressor is less than or equal to the predetermined rotation speed. By performing the heat storage operation, it is possible to store the amount of heat required for defrosting the air heat exchanger in the stopped heat exchange terminal.

Further, according to claim 4, the comfort of the air-conditioned space corresponding to the heat exchange terminal during operation can be maintained, the output of the compressor has a margin, and the defrosting operation is started. Immediately before, heat storage operation can be performed, and while maintaining the comfort of the air-conditioned space corresponding to the heat exchange terminal during operation, the amount required for defrosting the air heat exchanger at the stopped heat exchange terminal. The amount of heat can be stored, and the time for wastefully dissipating the amount of heat stored in the stopped heat exchange terminal before the defrosting operation is started is reduced, and a large amount of stored heat is transferred to the air heat exchanger. Can be used for defrosting.

Further, according to claim 5, the temperature level of the hot water supplied to the heat exchange terminal stopped among the plurality of heat exchange terminals during the heat storage operation is set to be higher than the temperature level that can be set during the normal heating operation. Since it is set low, it is possible to store as much heat as necessary for defrosting the air heat exchanger without unnecessarily heating the air-conditioned space corresponding to the stopped heat exchange terminal.

Further, according to claim 6, after a certain period of time has elapsed from the start of the heat storage operation, the flow control valve corresponding to the stopped heat exchange terminal is closed to end the heat storage operation, so that the stopped heat exchange terminal is supported. It is possible to store the amount of heat required for defrosting the air heat exchanger without unnecessarily heating the air-conditioned space.

The schematic block diagram of the heat pump type hot water heating system of one Embodiment of this invention. The figure which shows the screen display example of a remote controller. The figure which shows the screen display example of a remote controller at the time of a heating operation. The figure explaining the operation at the time of a heating operation. The figure explaining the operation at the time of a heat storage operation during a heating operation. The figure explaining the operation at the time of defrosting operation. The flowchart which shows the control procedure at the time of a heating operation. Another flowchart showing the control procedure during heating operation. Yet another flowchart showing the control procedure during heating operation. Another flowchart showing the control procedure during heating operation.

Next, the configuration of the heat pump type hot water heating system 1 according to the embodiment of the present invention will be described in detail with reference to the drawings.

Reference numeral 2 denotes a heat pump unit as a heat pump type heat source machine for supplying the heated circulating fluid. The heat pump unit 2 is a compressor 3 having a variable rotation speed for compressing the refrigerant in the housing, and a four-way valve as a flow path switching means. 4. Liquid refrigerant heat exchanger 5 that exchanges heat between the refrigerant and circulating fluid, expansion valve 6 as a decompression means, and air heat exchanger 8 that exchanges heat with the air (outside air) sent by the operation of the blower fan 7. The heat pump circuit 10 is formed by connecting them in a ring shape with a refrigerant pipe 9 to circulate the refrigerant. As the refrigerant that circulates in the heat pump circuit 10, any refrigerant such as an HFC refrigerant or a carbon dioxide refrigerant can be used. The liquid refrigerant heat exchanger 5 is composed of, for example, a plate type heat exchanger. In the plate type heat exchanger, a plurality of heat transfer plates are laminated, and a refrigerant flow path through which the refrigerant flows and a liquid through which the circulating liquid flows. The flow paths are alternately formed with each heat transfer plate as a boundary. Further, 11 is an outside air temperature sensor for detecting the outside air temperature, and 12 is provided in the refrigerant pipe 9 from the expansion valve 6 to the air heat exchanger 8, and the refrigerant passing through the air heat exchanger 8 on the low pressure side during the heating operation. It is a refrigerant temperature sensor that detects the temperature and also detects the temperature of the refrigerant that has passed through the air heat exchanger 8 that is on the high pressure side during the defrosting operation. The refrigerant temperature detected by the refrigerant temperature sensor 12 can be regarded as the temperature of the refrigerant flowing through the air heat exchanger 8.

The four-way valve 4 provided in the refrigerant pipe 9 has a function of switching the flow direction of the refrigerant in the heat pump circuit 10, and uses the refrigerant discharged from the compressor 3 as a liquid refrigerant heat exchanger 5, an expansion valve 6, and air. A state in which the heat exchanger 8 is circulated in this order to form a flow path for returning to the compressor 3 (state during heating operation), and a state in which the refrigerant discharged from the compressor 3 is passed through the air heat exchanger 8, the expansion valve 6, and the liquid. It is possible to switch to a state in which the refrigerant heat exchanger 5 is circulated in this order and a flow path for returning to the compressor 3 is formed (state during defrosting operation).

13 is connected to the heat pump unit 2 via an forward pipe 14 and a return pipe 15 as pipes, and the circulating liquid heated by the heat pump unit 2 is supplied, and the supplied circulating liquid is used as a heat source to heat the air-conditioned space. It is a heat exchange terminal. As the heat exchange terminal 13, a radiant terminal such as a floor heating panel, a radiant panel, or a radiator can be used. In FIG. 1, three heat exchange terminals 13A, 13B, and 13C are provided, but the number of heat exchange terminals 13 may be two or a plurality of three or more.

Here, one forward header 16 is provided in the middle of the forward pipe 14 extending from the liquid refrigerant heat exchanger 5 of the heat pump unit 2 toward the heat exchange terminal 13, and the forward header 16 of the forward pipe 14 is provided. The upstream portion is configured as one common going pipe 14a, and is a circulating fluid (for example, water, antifreeze, etc., which is heated by the liquid refrigerant heat exchanger 5 of the heat pump unit 2 and is hereinafter heated. Is appropriately expressed as hot water) is supplied. Then, in the portion of the outgoing pipe 14 on the downstream side of the outgoing header 16, individual outgoing pipes 14b of the number of heat exchange terminals 13 (three in the illustrated example) are branched. Thermal valves 17 (17A, 17B, 17C) as flow rate control valves are attached to the branched individual going pipes 14b, respectively.

Similarly, one return header 18 is provided in the middle of the return pipe 15 extending from the heat exchange terminal 13 toward the liquid refrigerant heat exchanger 5 of the heat pump unit 2, and the return header 18 of the return pipe 15 is provided. In the upstream portion, individual return pipes 15b are branched by the number of heat exchange terminals 13 (three in the illustrated example). The portion of the return pipe 15 downstream of the return header 18 is configured as one common return pipe 15a, and the circulating liquid introduced via the individual return pipes 15b is transferred to the liquid refrigerant heat exchanger 5 of the heat pump unit 2. And return.

The forward header 16 and the return header 18 may be provided inside the housing of the heat pump unit 2 as shown in the drawing, or may be provided outside the heat pump unit 2 housing.

Reference numeral 19 denotes a circulation circuit formed by connecting the liquid refrigerant heat exchanger 5 of the heat pump unit 2 and the heat exchange terminal 13 with the forward pipe 14 and the return pipe 15, and the circulating liquid circulates in the common return pipe 15a. The circulation circuit 19 includes a circulation pump 20 having a variable rotation speed for circulating the circulation liquid, and a systurn 21 for storing the circulation liquid and adjusting the pressure of the circulation circuit 19. Each of the individual return pipes 15b of the return pipe 15 has a return temperature sensor 22 (22A) as a return temperature detecting means for detecting the return temperature of the circulating liquid flowing into the liquid flow path of the liquid refrigerant heat exchanger 5. , 22B, 22C) are provided.

Reference numeral 23 denotes a remote controller installed on the indoor wall surface of a living room or the like. The remote controller 23 includes a display unit 24, an operation / stop switch 25 for instructing operation start / stop of the heat exchange terminal 13 as an operation switch, and heat exchange. A timer switch 26 for instructing the terminal 13 to operate with a timer, an operation changeover switch 27 for instructing the switching of the operation mode (normal mode, save mode, etc.) of the heat exchange terminal 13, and the screen display immediately before. A return switch 28 for returning to the screen, a menu / decision switch 29, and a cross key 30 in the up / down / left / right directions are provided. The remote controller 23 has a built-in CPU as a control means for performing various displays, a memory as a storage means, and the like, and transmits information by bidirectional communication with the control unit 31 described later. The remote controller 23 has a function as a setting means for setting the temperature level of the circulating fluid supplied to the heat exchange terminal 13, and in the present embodiment, the temperature levels 1 to 9 can be set.

Here, the display of the remote controller 23 will be described with reference to FIG. 2. The display unit 24 can switchably display a plurality of setting screens (screens 100 to 101) under the control of the CPU. That is, in the example shown in FIG. 2A, the display unit 24 displays the overall setting screen 100 for making settings related to the entire heat pump type hot water heating system 1. When the overall setting screen 100 is displayed on the display unit 24, the operating state of the heat pump unit 2 (heat source) is displayed in the center of the overall setting screen 100 (stopped in this example), and the heat pump unit 2 is in the main tab TM. A status display indicating the operating status of is displayed (in this example, "OFF", which is a stopped status, is displayed).

On the other hand, in the example shown in FIG. 2B, the display unit 24 displays a terminal setting screen 101 for making settings related to the heat exchange terminal 13, including the operation start / stop setting of the heat exchange terminal 13. .. The terminal setting screen 101 can be provided as many as the number corresponding to the number of heat exchange terminals 13 to be connected (three in this embodiment). When the terminal setting screen 101 is displayed on the display unit 24, the room name and operating state of the corresponding heat exchange terminal 13 are displayed in the center of the terminal setting screen 101, and the heat exchange terminal 13 is supplied to the right side of the screen. The temperature level of the hot water and the indicator showing the temperature level are displayed. In this example, the terminal setting screen 101 of the heat exchange terminal 13A corresponding to room A is displayed as the air-conditioned space, the hot water heating in room A is stopped in the center of the screen, and the temperature level of hot water is on the right side of the screen. It is displayed that it is set to 5. In the tab TA, a state display (“OFF” notation) indicating the operating state of the heat exchange terminal 13A corresponding to the room A is made. Although detailed description is omitted, the contents displayed on the terminal setting screen 101 of the heat exchange terminal 13B corresponding to room B and the terminal setting screen 101 of the heat exchange terminal 13C corresponding to room C correspond to the above room A. This is the same as the content displayed on the terminal setting screen 101 of the heat exchange terminal 13A.

In the present embodiment, one remote controller 23 can be used to set the operation of the three heat exchange terminals 13A, 13B, and 13C. However, the remote controller 23 is provided for each heat exchange terminal 13, and one remote controller 23 can be used. It may be such that the operation setting of one heat exchange terminal 13 can be performed.

Reference numeral 31 denotes a control unit including a storage means for storing various data and programs and a control means for performing calculation / control processing. The control unit 31 is a signal from various sensors in the heat pump unit 2 and a signal from the remote control 23. In response to this, it controls the drive of the compressor 3, the four-way valve 4, the expansion valve 6, the blower fan 7, the thermal valve 17, and the circulation pump 20, and the temperature of the hot water supplied to the heat exchange terminal 13 is the temperature of the remote control 23. The heat pump unit 2 (compressor 3, four-way valve 4, expansion valve 6, blower fan 7), thermal valve 17, and circulation pump 20 are controlled to perform heating operation so that the temperature level is set in. is there.

When the temperature of the hot water supplied to the heat exchange terminal 13 during the heating operation reaches the temperature level among the plurality of heat exchange terminals 13 during the heating operation, the control unit 31 may perform the plurality of heat exchange terminals 13. A heat storage control means for opening a heat valve 17 corresponding to at least one of the stopped heat exchange terminals 13 and performing a heat storage operation in which hot water is allowed to flow through the stopped heat exchange terminal 13 to store heat. It has 32. The details of the heat storage operation will be described later.

Further, the control unit 31 closes the heat valve 17 corresponding to the heat exchange terminal 13 during the heating operation among the plurality of heat exchange terminals 13 during the defrosting operation of the air heat exchanger 8 of the heat pump unit 2. It has a defrost control means 33 that controls to open the heat valve 17 corresponding to the stopped heat exchange terminal 13 that has performed the heat storage operation among the plurality of heat exchange terminals 13. The details of the defrosting operation will be described later.

Next, the operation of the heat pump type hot water heating system 1 during the heating operation will be described with reference to the drawings. Here, a scene in which the heating operation is performed by the heat exchange terminal 13A will be described.

First, when the operation / stop switch 25 of the remote controller 23 is operated by the user while the terminal setting screen 101 is displayed on the display unit 24 of the remote controller 23, and an instruction to start the heating operation of the heat exchange terminal 13A is given, the control unit At 31, the instruction signal is received. At this time, as shown in FIG. 3B, the operating state (A room temperature water heating operation) and the temperature level (level 5) are displayed on the display unit 24 of the remote controller 23, and the inside of the tab TA is displayed. It becomes "ON" notation. On the overall setting screen 100, as shown in FIG. 3A, the operating state (during operation) of the heat pump unit 2 (heat source) is displayed in the center of the screen, and the tab TM is marked with “ON”. Become.

When the instruction to start the heating operation is issued, the control unit 31 starts the operation of the heat pump circuit 10. Specifically, the control unit 31 switches the four-way valve 4 to the flow path during heating, and the compressor 3 and the blower fan 7 are used. The heating operation is started by starting the driving of the circulation pump 20 by opening the thermal valve 17A corresponding to the heat exchange terminal 13A by the control unit 31. During the heating operation, in the heat pump circuit 10, a high-temperature, high-pressure gaseous refrigerant compressed by the compressor 3 is discharged from the compressor 3, and the refrigerant is circulated by the liquid refrigerant heat exchanger 5 functioning as a condenser. It exchanges heat with the hot water flowing through the circuit 19, releases heat to the circulating fluid, and changes to a high-pressure refrigerant in a gas-liquid mixed state while heating. Then, the refrigerant in this state is depressurized by the expansion valve 6 to become a low-pressure refrigerant and easily evaporate, and in the air heat exchanger 8 functioning as an evaporator, the outside air and heat blown by the drive of the blower fan 7 After exchanging, heat is absorbed from the outside air to become a low-temperature, low-pressure gaseous refrigerant, which is returned to the compressor 3 again. (See the flow of refrigerant indicated by the arrow in FIG. 4).

In the circulation circuit 19, the hot water flowing into the liquid refrigerant heat exchanger 5 driven by the circulation pump 20 driven at a constant rotation speed is heat-exchanged with the refrigerant in the liquid refrigerant heat exchanger 5 functioning as a condenser and heated. After that, the heated hot water was supplied to the heat exchange terminal 13A to heat the air-conditioned space (room A) corresponding to the heat exchange terminal 13A, and was dissipated by the heat exchange terminal 13A to lower the temperature. The hot water returns to the liquid refrigerant heat exchanger 5 and is heated. Here, since the heating by the heat exchange terminal 13B and the heat exchange terminal 13C is stopped, the heat valve 17B corresponding to the heat exchange terminal 13B and the heat valve 17C corresponding to the heat exchange terminal 13C are closed. As shown in FIG. 4, the hot water heated by the liquid refrigerant heat exchanger 5 is circulated only to the heat exchange terminal 13A. (See the flow of hot water indicated by the arrow in Fig. 4.)

During the heating operation, the control unit 31 opens the thermal valve 17A and controls the rotation speed of the compressor 3 according to the detected value of the return temperature sensor 22A. That is, the rotation speed of the compressor 3 is controlled so that the hot water temperature detected by the return temperature sensor 22A becomes the target hot water temperature determined based on the temperature level set by the remote controller 23. As described above, the heat is controlled by controlling the rotation speed of the compressor 3 so that the hot water temperature detected by the return temperature sensor 22A becomes the target hot water temperature determined based on the temperature level set by the remote control 23. The temperature of the hot water supplied to the exchange terminal 13A is set to the temperature level. Here, when the hot water temperature detected by the return temperature sensor 22A reaches the target hot water temperature, it is determined that the temperature of the hot water supplied to the heat exchange terminal 13A has reached the temperature level set by the remote controller 23. To.

Explaining the rotation speed control of the compressor 3 in more detail, the control unit 31 determines the magnitude of the load from the temperature difference between the hot water temperature detected by the return temperature sensor 22A and the target hot water temperature, and determines the magnitude of the load. According to this, the rotation speed of the compressor 3 is controlled to increase or decrease, and when the hot water temperature detected by the return temperature sensor 22A does not reach the target hot water temperature, the rotation speed of the compressor 3 is increased. .. On the other hand, when the hot water temperature detected by the return temperature sensor 22A reaches the target hot water temperature, the rotation speed of the compressor 3 is reduced in order to maintain the hot water temperature detected by the return temperature sensor 22A at the target hot water temperature. It is something that makes you.

The heating operation was continued, and the hot water temperature detected by the return temperature sensor 22A reached the target hot water temperature (= the temperature of the hot water supplied to the heat exchange terminal 13A reached the temperature level set by the remote control 23. In that case, the heat storage control means 32 opens the heat valve 17 (17B, 17C) corresponding to the heat exchange terminal 13 (13B, 13C) currently stopped in the heat exchange terminal 13 and stops the heat exchange terminal 13. Hot water is passed through the heat exchange terminals 13 (13B, 13C) inside, and heat to be used for defrosting the air heat exchanger 8 is stored in the stopped heat exchange terminals 13 (13B, 13C). Have the heat storage operation performed. In the present embodiment, as shown in FIG. 5, the thermal valves 17 (17B, 17C) of all the stopped heat exchange terminals 13 (13B, 13C) are opened, but a plurality of heat exchange terminals are opened. It suffices to open the thermal valve 17 corresponding to at least one of the stopped heat exchange terminals 13 in 13.

As described above, the heat storage control means 32 performs the heat storage operation when the hot water temperature detected by the return temperature sensor 22A reaches the target hot water temperature, but the heat storage control means 32 is detected by the return temperature sensor 22A. When the hot water temperature reaches the target hot water temperature, the hot water temperature detected by the return temperature sensor 22A reaches the target hot water temperature, or the hot water temperature detected by the return temperature sensor 22A reaches the target hot water temperature. After that, the case where the hot water temperature detected by the return temperature sensor 22A continuously for a predetermined time is detected to be equal to or higher than the target hot water temperature is included.

The temperature level of the hot water supplied to the stopped heat exchange terminals 13 (13B, 13C) during the heat storage operation is set lower than the lower limit (level 1) of the temperature level that can be set during the normal heating operation. The heat storage control means 32 closes the heat valve 17 (17B, 17C) corresponding to the stopped heat exchange terminal 13 (13B, 13C) after a certain period of time has elapsed from the start of the heat storage operation. And end the heat storage operation. The method of ending the heat storage operation is not limited to the elapse of a certain period of time from the start of the heat storage operation as described above. For example, during the heat storage operation, the heat exchange is circulated to the stopped heat exchange terminal 13 and the stopped heat exchange When the hot water temperature detected by the return temperature sensor 22 corresponding to the terminal 13 reaches the target hot water temperature corresponding to the heat storage level, the thermal valve 17 corresponding to the stopped heat exchange terminal 13 is closed. The heat storage operation may be terminated.

Further, when a predetermined time has elapsed after the end of the heat storage operation and the temperature of the hot water supplied to the heat exchange terminal 13 during the heating operation reaches the temperature level, the heat storage operation is executed again. As described above, the heat storage operation may be performed periodically.

When the outside air temperature is low during the heating operation, the air heat exchanger 8 gradually frosts. If it is determined that frost has adhered to the air heat exchanger 8 during the heating operation, the defrost control means 33 executes a defrosting operation to melt the frost of the air heat exchanger 8.

The mode of the defrosting operation is a form in which the refrigerant is circulated in the direction opposite to that during the heating operation. Specifically, in the defrosting operation, the expansion valve 6 is expanded to a predetermined opening degree (for example, fully open) as compared with the heating operation. At the same time, the four-way valve 4 is switched to the state during the defrosting operation so that the flow direction of the refrigerant is opposite to the flow direction of the refrigerant during the heating operation, and the refrigerant discharged from the compressor 3 is used in the air heat exchanger. It is directly supplied to 8 to melt the frost generated in the air heat exchanger 8. The refrigerant whose temperature has dropped due to heat exchange with frost in the air heat exchanger 8 passes through the expansion valve 6 without being depressurized by the expansion valve 6, is heated by hot water in the liquid refrigerant heat exchanger 5, and is again compressed by the compressor. It returns to 3. (Refer to the flow of the refrigerant indicated by the arrow in FIG. 6.) The temperature of the hot water circulating in the circulation circuit 19 is lowered by heat exchange with the refrigerant in the liquid refrigerant heat exchanger 5.

The start of the defrosting operation is, for example, defrosting control of whether or not the outside air temperature detected by the outside air temperature sensor 11 and the refrigerant temperature detected by the refrigerant temperature sensor 12 have reached preset defrosting start temperatures. The means 33 determines, that is, whether or not the predetermined defrosting start condition is satisfied, and the defrosting control means 33 determines, and when it is determined that the defrosting start condition is satisfied, the defrosting operation can be started.

Further, when the defrosting operation is completed, the defrosting control means determines whether or not the temperature of the refrigerant flowing through the air heat exchanger 8 detected by the refrigerant temperature sensor 12 has reached a preset defrosting end temperature. 33 determines, that is, whether or not the predetermined defrosting end condition is satisfied is determined by the defrosting control means 33, and when it is determined that the defrosting end condition is satisfied, the defrosting operation can be terminated.

During the defrosting operation, the defrosting control means 33 closes the heat valve 17A corresponding to the heat exchange terminal 13A during the heating operation while driving the circulation pump 20, and heat exchange is stopped during the heat storage operation. The heat valve 17B corresponding to the terminal 13B and the heat valve 17C corresponding to the stopped heat exchange terminal 13C that stores heat during the heat storage operation are opened. By doing so, the heat valve 17A corresponding to the heat exchange terminal 13A being operated during the defrosting operation is closed, and the hot water whose temperature has dropped due to the defrosting operation does not flow to the heat exchange terminal 13A. (See the flow of hot water indicated by the arrow line in FIG. 6), it is possible to prevent the room temperature of the room A corresponding to the heat exchange terminal 13A from dropping, and the comfort is not impaired. On the other hand, the heat valve 17B corresponding to the heat exchange terminal 13B that is stopped during the defrosting operation and the heat valve 17C corresponding to the heat exchange terminal 13C that is stopped during the operation are opened to exchange heat stored during the heat storage operation. Hot water in the terminal 13B and the heat exchange terminal 13C is circulated (see the flow of hot water indicated by the arrow in FIG. 6), and the heat held by the hot water in the liquid refrigerant heat exchanger 5 is used as a refrigerant for defrosting. Since it is pumped to the side, the temperature of the refrigerant is high, and the defrosting operation time for defrosting the air heat exchanger 8 can be significantly shortened as compared with the conventional case. When all the heat exchange terminals 13 (13A, 13B, 13C) are in the heating operation at the start of the defrosting operation (when the defrosting start condition is satisfied), the defrosting control means 33 uses those heat exchange terminals. The defrosting operation is performed while all the thermal valves 17 (17A, 17B, 17C) corresponding to 13 (13A, 13B, 13C) are opened.

Next, the control procedure of the operation during the heating operation will be described with reference to the flowchart of FIG. Here, as shown in FIGS. 4 to 6, the description will be made based on the situation where the heating operation is performed by the heat exchange terminal 13A among the plurality of heat exchange terminals 13.

The heating operation by the heat exchange terminal 13 (heat exchange terminal 13A) is started, and in step S1, the control unit 31 sets the temperature of the hot water supplied to the heat exchange terminal 13 (heat exchange terminal 13A) by the remote control 23. It is determined whether or not the temperature level has been reached (= whether or not the hot water temperature detected by the return temperature sensor 22A has reached the target hot water temperature). The determination in step S1 is not satisfied (S1: NO) until the hot water temperature reaches the set temperature level, and the loop waits. When the hot water temperature reaches the set temperature level, the determination in step S1 is satisfied (S1: NO). S1: YES), the process proceeds to step S2.

In step S2, the heat storage control means 32 determines whether or not there is a heat exchange terminal 13 currently stopped among the plurality of heat exchange terminals 13. When there is no stopped heat exchange terminal 13, that is, when all the heat exchange terminals 13 are in the heating operation, the determination in step S2 is not satisfied (S2: NO), and the process returns to the process of S1. On the other hand, if there is a stopped heat exchange terminal 13 (heat exchange terminals 13B, 13C), the determination in step S2 is satisfied (S2: YES), and the process proceeds to step S3.

In step S3, the heat storage control means 32 starts the heat storage operation, and specifically, the heat operation corresponding to the heat exchange terminals 13 (heat exchange terminals 13B, 13C) currently stopped among the plurality of heat exchange terminals 13. The valves 17 (heat exchange valves 17B, 17C) are opened, hot water is circulated to the stopped heat exchange terminals 13 (heat exchange terminals 13B, 13C), and the process proceeds to step S4. In step S3, the temperature level of the hot water supplied to the stopped heat exchange terminals 13 (13B, 13C) is lower than the lower limit of the temperature level (level 1) that can be set during normal heating operation. It is set to the set heat storage level.

In step 4, the heat storage control means 32 determines whether or not a certain time (for example, 10 minutes) has elapsed since the start of the heat storage operation. Until a certain time elapses, the determination in step S4 is not satisfied (S4: NO), and the loop waits. When a certain time elapses, the determination in step S4 is satisfied (S4: YES), and the process proceeds to step S5.

In step S5, the heat storage control means 32 closes the heat valve 17 (heat valve 17B, 17C) corresponding to the stopped heat exchange terminal 13 (heat exchange terminals 13B, 13C), and heat is stopped. The hot water circulation to the exchange terminals 13 (heat exchange terminals 13B and 13C) is stopped to end the heat storage operation, and the process proceeds to step 6.

In step S6, the defrost control means 33 determines whether or not the predetermined defrost start condition is satisfied. Until the predetermined defrosting start condition is satisfied, the determination in step S6 is not satisfied (S6: NO), and the loop waits. When the predetermined defrosting start condition is satisfied, the determination in step S6 is satisfied (S6: YES). , Step S7.

In step S7, the defrost control means 33 controls the heat pump unit 2 at the same time, such as switching the four-way valve 4 so that the circulation direction of the refrigerant circulating in the heat pump circuit 10 is opposite to that during the heating operation. In the heat exchange terminal 13, the heat valve 17 (heat valve 17A) corresponding to the heat exchange terminal 13 (heat exchange terminal 13A) during the heating operation is closed, and the heat exchange terminal 13 (heat) during the heating operation is closed. The heat valve 17 (heat valve) corresponding to the stopped heat exchange terminals 13 (heat exchange terminals 13B, 13C) that stopped the hot water circulation to the exchange terminal 13A) and stored the heat for defrosting by the heat storage operation. 17B, 17C) is opened, hot water circulation to the stopped heat exchange terminals 13 (heat exchange terminals 13B, 13C) is started, and the process proceeds to step S8. In step S7, the defrost control means 33 is also at the timing when the stopped heat exchange terminals 13 (heat exchange terminals 13B and 13C) that have stored heat for defrosting during the heat storage operation start the defrost operation. When it is determined that the system is stopped, the heat valve 17 (heat valve 17B, 13C) corresponding to the stopped heat exchange terminal 13 (heat exchange terminals 13B, 13C) that stores heat for defrosting by the heat storage operation. 17C) is opened.

In step S8, the defrost control means 33 determines whether or not the predetermined defrost end condition is satisfied. Until the predetermined defrosting end condition is satisfied, the determination in step S8 is not satisfied (S8: NO), and the loop waits. When the predetermined defrosting end condition is satisfied, the determination in step S8 is satisfied (S8: YES). , Step S9.

In step S9, the defrost control means 33 is a thermal valve 17 corresponding to the heat exchange terminal 13 (heat exchange terminal 13A) that was in the heating operation before the defrost operation was performed among the plurality of heat exchange terminals 13. (Thermal valve 17A) is opened to restart the hot water circulation to the heat exchange terminal 13 (heat exchange terminal 13A), and the thermal operation corresponding to the stopped heat exchange terminal 13 (heat exchange terminals 13B, 13C). The valves 17 (heat-driven valves 17B, 17C) are closed, the hot water circulation to the stopped heat exchange terminals 13 (heat exchange terminals 13B, 13C) is stopped, and the defrosting operation is terminated. Further, the defrost control means 33 controls the heat pump unit 2 to restart the heating operation, such as switching the four-way valve 4 so that the circulation direction of the refrigerant circulating in the heat pump circuit 10 is the direction during the heating operation.

As described above, according to the heat pump type hot water heating system 1 of the present embodiment, the temperature of the hot water supplied to the heat exchange terminal 13 being operated among the plurality of heat exchange terminals 13 during the heating operation is the temperature. When the level is reached, the heat valve 17 corresponding to the stopped heat exchange terminal 13 among the plurality of heat exchange terminals 13 is opened, and hot water is allowed to flow through the stopped heat exchange terminal 13 to store heat. When the defrosting operation is performed during the heating operation, the heat valve 17 corresponding to the heat exchange terminal 13 in operation is closed among the plurality of heat exchange terminals 13, and heat is stored during the heat storage operation. The heat valve 17 corresponding to the stopped heat exchange terminal 13 is opened.

As a result, until the temperature of the hot water supplied to the heat exchange terminal 13 during the heating operation reaches the temperature level, the hot water is circulated only to the heat exchange terminal 13 during the heating operation, and the heat exchange terminal 13 during the heating operation is circulated. It is possible to quickly heat the air-conditioned space corresponding to. Further, when the temperature of the hot water supplied to the heat exchange terminal 13 during operation reaches the temperature level, that is, the load on the air-conditioned space corresponding to the heat exchange terminal 13 during operation is reduced, and the air-conditioned space becomes When the room temperature becomes stable, the heat valve 17 corresponding to the stopped heat exchange terminal 13 other than the heat valve 17 corresponding to the operating heat exchange terminal 13 is also opened to allow hot water to flow. It is possible to store heat for defrosting in the stopped heat exchange terminal 13 while maintaining a stable state (comfort) of the room temperature of the air-conditioned space corresponding to the heat exchange terminal 13 during the heating operation. Then, during the defrosting operation, the heat valve 17 corresponding to the heat exchange terminal 13 during the heating operation is closed, so that the hot water whose temperature has dropped due to the defrosting operation does not flow to the heat exchange terminal 13 during the operation. It is possible to moderate the decrease in the room temperature of the air-conditioned space corresponding to the heat exchange terminal 13 during operation without impairing comfort, and on the other hand, the stop heat is stored during the heat storage operation. Since the heat valve 17 corresponding to the heat exchange terminal 13 inside is opened and the hot water in the heat exchange terminal 13 is circulated, the heat held by the hot water in the liquid refrigerant heat exchanger 5 is used for defrosting. As a result, the temperature of the refrigerant can be raised, and the defrosting operation time when defrosting the air heat exchanger 8 can be shortened.

Further, in the present embodiment, in particular, during the heat storage operation, the temperature level of the hot water supplied to the heat exchange terminal 13 that is stopped among the plurality of heat exchange terminals 13 can be set to a temperature level that can be set during the normal heating operation. Since the heat storage level is set to be lower than the lower limit (level 1), the air heat exchanger 8 can be defrosted without wastefully heating the air-conditioned space corresponding to the stopped heat exchange terminal 13. The required amount of heat can be stored.

Further, in the present embodiment, particularly during the heat storage operation, the heat storage control means 32 closes the heat valve 17 corresponding to the stopped heat exchange terminal 13 after a certain time has elapsed from the start of the heat storage operation, and performs the heat storage operation. Since it is terminated, the amount of heat required for defrosting the air heat exchanger 8 can be stored without wastefully heating the air-conditioned space corresponding to the stopped heat exchange terminal 13.

The present invention is not limited to the above embodiment, and various modifications can be made without changing the gist of the invention.

For example, in the above embodiment, the heat storage operation is performed when the temperature of the hot water supplied to the heat exchange terminal 13 during operation reaches the temperature level, but as another modification, the heat storage control means In 32, the defrosting operation is started directly from the heat storage preparation conditions set based on the outside air temperature and the refrigerant temperature of the air heat exchanger 8, that is, the outside air temperature and the refrigerant temperature of the air heat exchanger 8. The condition presumed to be (the condition that is satisfied before the defrosting start condition is satisfied) is stored in advance, and the flowchart of FIG. 8 (processing other than step S100 described later is the same as the flowchart of FIG. 7). As shown in), the heat storage control means 32 is in the case where the temperature of the hot water supplied to the heat exchange terminal 13 during operation reaches the temperature level (S1: YES), and the outside air temperature. When it is determined that the heat storage preparation condition is satisfied based on the outside air temperature detected by the sensor 11 and the refrigerant temperature detected by the refrigerant temperature sensor 12 (S100: YES), the heat storage operation may be performed. By doing so, the heat storage operation can be performed immediately before the defrosting operation is started, and the amount of heat stored in the stopped heat exchange terminal 13 is wasted before the defrosting operation is started. A large amount of heat stored can be used for defrosting the air heat exchanger 8.

Further, in the above embodiment, the heat storage operation is performed when the temperature of the hot water supplied to the heat exchange terminal 13 during operation reaches the temperature level, but as another modification, FIG. 9 As shown in the flowchart (the processing other than step S200 described later is the same as the flowchart of FIG. 7, the description thereof will be omitted), the temperature of the hot water supplied by the heat storage control means 32 to the heat exchange terminal 13 during operation. Is when the temperature level is reached (S1: YES), and when it is determined that the rotation speed of the compressor 3 being driven is lower than the upper limit rotation speed and is equal to or less than a preset predetermined rotation speed (for example, 70 rps) (for example). The heat storage operation may be performed in S200: YES), and by doing so, the load on the air-conditioned space corresponding to the heat exchange terminal 13 during the heating operation is large, and the heat exchange terminal 13 during operation is large. Although it was possible to raise the temperature of the hot water supplied to the engine to the set temperature level, when the air-conditioned space was fully heated and there was not much room in the output of the compressor 3 (the number of revolutions of the compressor 3). Is higher than the predetermined number of revolutions), the heat storage operation is not performed, and the comfort is maintained by concentrating on heating the air-conditioned space corresponding to the heat exchange terminal 13 during operation, and the output of the compressor 3 has a margin. In a certain state (when the rotation speed of the compressor 3 is equal to or less than the predetermined rotation speed), the heat storage operation can be performed, and the amount of heat required for defrosting the air heat exchanger 8 at the stopped heat exchange terminal 13 Can store heat.

Further, in the above embodiment, the heat storage operation is performed when the temperature of the hot water supplied to the heat exchange terminal 13 during operation reaches the temperature level, but as yet another modification, heat storage control is performed. The defrosting operation is directly started in the means 32 from the heat storage preparation conditions set based on the outside air temperature and the refrigerant temperature of the air heat exchanger 8, that is, the outside air temperature and the refrigerant temperature of the air heat exchanger 8. The condition presumed to be (condition that is satisfied before the defrosting start condition is satisfied) is stored in advance, and the flowchart of FIG. 10 (processing other than steps S300 and S400 described later is the flowchart of FIG. 7). As shown in (S1: YES), the heat storage control means 32 is in the case where the temperature of the hot water supplied to the heat exchange terminal 13 during operation reaches the temperature level (S1: YES). Further, when it is determined that the rotation speed of the compressor 3 being driven is lower than the upper limit rotation speed and is equal to or less than a preset predetermined rotation speed (for example, 70 rps) (S300: YES), the outside air temperature sensor 11 detects it. When it is determined that the heat storage preparation condition is satisfied based on the outside air temperature and the refrigerant temperature detected by the refrigerant temperature sensor 12 (S400: YES), the heat storage operation may be performed. By doing so, the heat storage operation may be performed. The heat storage operation is performed when the comfort of the air-conditioned space corresponding to the heat exchange terminal 13 during operation can be maintained, the output of the compressor 3 has a margin, and immediately before the defrosting operation is started. This can be done, and while maintaining the comfort of the air-conditioned space corresponding to the operating heat exchange terminal 13, heat is stored in the stopped heat exchange terminal 13 as much as necessary for defrosting the air heat exchanger 8. Further, the time for wastefully dissipating the amount of heat stored in the heat exchange terminal 13 that is stopped before the defrosting operation is started is reduced, and a large amount of the stored heat is transferred to the air heat exchanger 8. Can be used for defrosting.

In the present embodiment, it has been described that the heat exchange terminal 13A is in operation and the heat exchange terminals 13B and 13C are stopped among the plurality of heat exchange terminals 13, but the present invention is applied to this combination. For example, the heat exchange terminal 13B may be in operation and the heat exchange terminals 13A and 13C may be stopped in the plurality of heat exchange terminals 13, and the heat in the plurality of heat exchange terminals 13 may be stopped. Two of the exchange terminals 13A and 13B may be in operation, and only one of the heat exchange terminals 13C may be stopped.

In addition, although not illustrated one by one, the present invention is carried out with various modifications within a range not deviating from the gist thereof.

1 Heat pump type hot water heating system 2 Heat pump unit 3 Compressor 5 Liquid refrigerant heat exchanger 6 Expansion valve 8 Air heat exchanger 13A, 13B, 13C Heat exchange terminal 14 Outgoing pipe 15 Return pipe 17A, 17B, 17C Thermal valve 19 Circulation Circuit 20 Circulation pump 23 Remote control 31 Control unit 32 Heat storage control means 33 Defrost control means

Claims (6)

A heat pump type heat source machine having a compressor for compressing the refrigerant, a liquid refrigerant heat exchanger for heat exchange between the circulating liquid and the refrigerant, a decompression means, and an air heat exchanger.
The liquid refrigerant heat exchanger of the heat pump type heat source machine, a plurality of heat exchange terminals that heat the air-conditioned space using the circulating liquid as a heat source, and individual flow control valves corresponding to the plurality of heat exchange terminals. A circulation circuit for circulating the circulating fluid, which is formed by connecting the circulating pump for circulating the circulating fluid with a pipe,
A setting means for setting the temperature level of the circulating fluid supplied to the heat exchange terminal, and
A control unit that controls the heat pump type heat source machine and the flow rate control valve to perform a heating operation so that the temperature of the circulating fluid supplied to the heat exchange terminal becomes the temperature level.
In a heat pump type hot water heating system equipped with
During the heating operation, when the temperature of the circulating fluid supplied to the heat exchange terminals operating in the plurality of heat exchange terminals reaches the temperature level, the heat exchange terminals stop in the plurality of heat exchange terminals. A heat storage control means for performing a heat storage operation in which the flow control valve corresponding to at least one of the heat exchange terminals inside is opened and the circulating liquid is allowed to flow through the stopped heat exchange terminal to store heat.
During the defrosting operation of the air heat exchanger of the heat pump type heat source machine, the flow control valve corresponding to the operating heat exchange terminal is closed in the plurality of heat exchange terminals, and the inside of the plurality of heat exchange terminals is closed. The defrost control means for opening the flow control valve corresponding to the stopped heat exchange terminal in which the heat storage operation was performed in
A heat pump type hot water heating system characterized by the provision of. The heat storage control means stores in advance heat storage preparation conditions set based on the outside air temperature and the refrigerant temperature of the air heat exchanger, and supplies the heat storage terminal to the operating heat exchange terminal among the plurality of heat exchange terminals. The heat pump type hot water heating system according to claim 1, wherein the heat storage operation is performed when the temperature of the circulating liquid reaches the temperature level and the heat storage preparation condition is satisfied. In the heat storage control means, the temperature of the circulating fluid supplied to the operating heat exchange terminal among the plurality of heat exchange terminals reaches the temperature level, and the rotation speed of the compressor reaches a predetermined rotation speed. The heat pump type hot water heating system according to claim 1, wherein the heat storage operation is performed in the following cases. The heat storage control means stores in advance heat storage preparation conditions set based on the outside air temperature and the refrigerant temperature of the air heat exchanger, and supplies the heat storage terminal to the operating heat exchange terminal among the plurality of heat exchange terminals. When the temperature of the circulating liquid reaches the temperature level, the rotation speed of the compressor is equal to or less than the predetermined rotation speed, and the heat storage preparation condition is satisfied, the heat storage operation is performed. The heat pump type hot water heating system according to claim 1. During the heat storage operation, the temperature level of the circulating fluid supplied to the stopped heat exchange terminal among the plurality of heat exchange terminals is set lower than the temperature level that can be set during the normal heating operation. The heat pump type hot water heating system according to any one of claims 1 to 4, wherein the heat pump type hot water heating system is provided. Any one of claims 1 to 5, wherein the heat storage control means closes the flow control valve corresponding to the stopped heat exchange terminal after a certain time has elapsed from the start of the heat storage operation. Heat pump type hot water heating system described in.

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