JP2020153632A - Chiller unit - Google Patents

Abstract

To provide a chiller unit capable of being quickly switched in changing a flowing direction of water in a water pipe connected to a water heat exchanger, and suppressing occurrence of problems.SOLUTION: A chiller unit includes first and second refrigeration cycle systems R1, R2 having first and second water heat exchangers 9A, 9B, a water pipe 18 connected to the first and second water heat exchangers 9A, 9B to circulate the water, and a four-way valve 20 disposed in the water pipe 18. A second connection port 22 and a connection port at one end side, of the first water heat exchanger 9A are connected by a water pipe 18b, a third connection port 23 and a connection port at the other end side, of the second heat exchanger 9B are connected by a water pipe 18c, and the four way vale 20 has a constitution switchable between a first mode in which the first connection port 21 and the second connection port 22, and the third connection port 23 and the fourth connection port 24 can be respectively communicated, and a second mode in which the first connection port 21 and the third connection port 23, and the second connection port 22 and the fourth connection port 24 can be respectively communicated.SELECTED DRAWING: Figure 2

Description

The present invention relates to a chiller unit.

The chiller unit comprises one or more refrigeration cycles and produces cold or hot water by exchanging heat between the refrigerant and water in a water heat exchanger connected to the refrigeration cycle. The generated cold water or hot water is guided to the outside and used for indoor heating and cooling and hot water supply.

The heat exchanger of the chiller unit is configured so that the refrigerant circulating in the refrigeration cycle and the water flowing through the water pipe can exchange heat. In a heat exchanger, heat exchange can be performed more efficiently in a countercurrent flow in which the refrigerant flow direction and the water flow direction face each other than in a parallel flow in which the refrigerant flow direction and the water flow direction are the same.

Japanese Unexamined Patent Publication No. 2014-130003

In the refrigeration cycle in the chiller unit, the flow direction of the refrigerant is opposite between the cooling operation and the heating operation, so the flow direction of the refrigerant and the flow direction of the water in the heat exchanger are parallel according to the switching of the operation. Or it becomes a countercurrent.

In the chiller unit, a plate heat exchanger is generally used. As a method of determining the inlet and outlet of the heat exchanger, the liquefied refrigerant among the refrigerants flowing in the refrigeration cycle flows in and out at the lower connection port of the heat exchanger, and the gasified refrigerant flows in and out of the upper connection port of the heat exchanger. It is decided to flow in and out from. That is, in the cooling operation, since the heat exchanger functions as an evaporator, it is determined that the liquid refrigerant flows in from the lower side and the gas refrigerant flows out from the upper side. Further, in the heating operation, since the heat exchanger functions as a condenser, it is determined that the gas refrigerant flows in from the upper side and the liquid refrigerant flows out from the lower side.

Therefore, the connection ports of the liquid refrigerant and the gas refrigerant in the heat exchanger cannot be changed according to the switching of the refrigeration cycle operation. That is, the flow direction of the refrigerant in the heat exchanger and the flow direction of the water pipe can be changed by changing the connection ports of the liquid refrigerant and the gas refrigerant according to the switching of the refrigeration cycle operation while keeping the flow of the water pipe constant. Cannot always be countercurrent.

Therefore, in Patent Document 1, the connection ports of the liquid refrigerant and the gas refrigerant in the refrigeration cycle are kept constant, and the flow direction of the refrigerant in the heat exchanger and the flow direction of the water pipe are changed according to the switching of the refrigeration cycle operation. The flow direction of the water pipe is changed so that the flow is always countercurrent. Patent Document 1 discloses that a three-way valve and a branch pipe branched from the three-way valve are installed in the water pipe in order to change the flow direction of the water pipe in the heat exchanger, and the three-way valve is switched.

However, in a configuration in which a three-way valve and a branch pipe are installed in a water pipe, when water flows in one direction, water flows through the branch pipe and the main pipe branched from the three-way valve, whereas the water flows in one direction. When flowing in the opposite direction, water flows only in the main pipe and no water flows in the branch pipe. Therefore, in either the cooling operation or the heating operation, in the water pipe, a state in which water does not always flow to the branch pipe may occur. As a result, rust is generated in the pipe, and maintenance work such as draining the water in the branch pipe is required when switching the operation.

The present invention has been made in view of such circumstances, and when the water flow direction in the water pipe connected to the water heat exchanger is changed, the water flow direction can be changed quickly, and a problem occurs. It is intended to provide a chiller unit that can be made difficult.

In order to solve the above problems, the chiller unit of the present invention employs the following means.
That is, the chiller unit according to the present invention has a water heat exchanger and is installed in a refrigeration cycle system in which a refrigerant circulates, a water pipe connected to the water heat exchanger and in which water flows, and the water pipe. A four-way valve having a first connection port, a second connection port, a third connection port, and a fourth connection port is provided, and the water flowing through the water pipe at the first connection port always flows into the four-way valve. The water flowing through the water heat exchanger at the fourth connection port always flows out from the four-way valve, and the second connection port and the connection port on one end side of the water heat exchanger are connected by the water pipe. The third connection port and the connection port on the other end side of the water heat exchanger are connected by the water pipe, and the four-way valve allows the first connection port and the second connection port to flow. , The first mode in which the third connection port and the fourth connection port can be distributed, or the first connection port and the third connection port can be distributed, and the second connection port and the fourth connection port can be distributed. It has a configuration in which the connection port can be switched to the second mode in which distribution is possible.

According to this configuration, when the four-way valve is switched to the first mode, the water flowing through the water pipe flows in at the first connection port, and after the water flows from the first connection port to the second connection port, the first 2 Water is supplied to the water heat exchanger from the connection port. Further, in the first mode, the water flowing through the water heat exchanger flows in from the third connection port, the water flows from the third connection port to the fourth connection port, and then the water flows out from the fourth connection port to the outside. To do. Further, when the four-way valve is switched to the second mode, water flowing through the water pipe flows in at the first connection port, water flows from the first connection port to the third connection port, and then from the third connection port. Water is supplied to the water heat exchanger. Further, in the second mode, the water flowing through the water heat exchanger flows in from the second connection port, the water flows from the second connection port to the fourth connection port, and then the water flows out from the fourth connection port to the outside. To do.

Therefore, it is possible to change the flow direction of the water pipe connected to the heat exchanger by switching the four-way valve. Therefore, by switching the four-way valve according to the switching between the cooling operation and the heating operation of the refrigeration cycle system, the flow direction of the refrigerant in the refrigeration cycle system and the flow direction of the water pipe can always be countercurrent. In addition, regardless of the switching of the four-way valve, water always flows in the water pipe, and there is no system in which water does not flow. Therefore, when changing the flow direction of the water pipe connected to the heat exchanger, the water flow direction can be quickly switched, and problems can be less likely to occur.

Further, since the number of installed four-way valves is one, which is smaller than the number of installed three-way valves, the number of parts can be reduced. Further, when a three-way valve is installed, a plurality of three-way valves need to operate, whereas one four-way valve only needs to operate, so that a switching problem due to an operation error is unlikely to occur.

In the above invention, the four-way valve may be installed inside the unit body.

According to this configuration, since the four-way valve is installed inside the unit body, the flow direction of the refrigerant in the refrigeration cycle system and the flow direction of the water pipe can always be changed simply by connecting the chiller unit to the external water pipe. A system that can be countercurrent can be configured.

In the above invention, the four-way valve may be installed outside the unit body and connected to the water pipe installed inside the unit body.

According to this configuration, since the four-way valve is installed outside the unit body, by connecting the four-way valve to the water pipe installed inside the unit body, the flow direction of the refrigerant in the refrigeration cycle system can be determined. It is possible to construct a system in which the flow direction of the water pipe can always be countercurrent. Since the four-way valve is not installed inside the unit body, the unit body can be applied to a configuration in which the flow direction of the water pipe does not need to be switched.

In the above invention, in the refrigeration cycle system, a temperature detection unit installed on the upstream side or the downstream side of the connection port of the water heat exchanger to detect the temperature of the refrigerant flowing through the refrigeration cycle system, and the temperature detection unit. A control unit that switches the four-way valve based on the temperature detected by the unit may be provided.

According to this configuration, in the refrigeration cycle system, the temperature of the refrigerant flowing through the refrigeration cycle system is detected by the temperature detection unit installed on the upstream side or the downstream side of the connection port of the water heat exchanger, and the detected temperature. Based on, the four-way valve is switched. The temperature of the refrigerant flowing upstream or downstream of the connection port of the water heat exchanger is changed according to the switching between the cooling operation and the heating operation of the refrigeration cycle system. As a result, the four-way valve is automatically switched according to the detected temperature of the refrigerant, and the flow direction of the refrigerant in the refrigeration cycle system and the flow direction of the water pipe can always be countercurrent.

In the above invention, the pressure detection unit installed in the refrigeration cycle system and detecting the pressure of the refrigerant flowing through the refrigeration cycle system, and the control unit are the four-way valve based on the pressure detected by the pressure detection unit. The success or failure of valve switching may be determined.

According to this configuration, the pressure detection unit installed in the refrigeration cycle system detects the pressure of the refrigerant flowing through the refrigeration cycle system, and the success or failure of the four-way valve switching is determined based on the detected pressure. Therefore, by detecting the temperature of the refrigerant, it can be determined whether or not the four-way valve is correctly switched.

According to the present invention, when changing the flow direction of water in the water pipe connected to the water heat exchanger, it is possible to quickly switch the water flow direction and to prevent problems from occurring.

It is a circuit diagram which shows the schematic structure of the chiller unit which concerns on one Embodiment of this invention. It is the schematic which shows the structure of the water pipe of the chiller unit which concerns on one Embodiment of this invention, and shows the state which the four-way valve is switched to the 1st mode. It is the schematic which shows the structure of the water pipe of the chiller unit which concerns on one Embodiment of this invention, and shows the state which the four-way valve is switched to the 2nd mode. It is the schematic which shows the modification of the structure of the water pipe of the chiller unit which concerns on one Embodiment of this invention.

Hereinafter, the chiller unit 1 according to the embodiment of the present invention will be described. FIG. 1 is a circuit diagram showing a schematic configuration of a chiller unit 1 according to an embodiment of the present invention.
The chiller unit 1 has a configuration in which two refrigeration cycle systems, that is, first and second refrigeration cycle systems R1 and R2, and a water system unit 3 are housed inside a housing (not shown). Further, the first refrigeration cycle system R1 and the second refrigeration cycle system R2 are arranged in series in the water pipe 18. The configuration of the water pipe 18 according to the present embodiment is shown in FIGS. 2 and 3, and FIG. 1 shows the configuration of the water pipe 18 in a simplified manner.

The number of refrigeration cycle systems included in the chiller unit 1 and the arrangement relationship of the refrigeration cycle system with respect to the water pipe 18 are not limited to the examples described in this embodiment. For example, the refrigeration cycle system may be one or three or more. Further, the plurality of refrigeration cycle systems may be arranged in parallel in the water pipe 18, or a series arrangement and a parallel arrangement may be combined.

The first and second refrigeration cycle systems R1 and R2 consist of a compressor 5, an oil separator 6, a check valve 7, a four-way valve 8, and a water heat exchanger 9 (first and second water heat exchanges, respectively). The vessels 9A and 9B), the receiver 10, the electronic expansion valve 11, the air-cooled heat exchanger 12, and the gas-liquid separator 13 are provided. The air-cooled heat exchanger 12 is provided with a cooling fan 12a.

The compressor 5 sucks in the gas refrigerant, compresses the sucked gas refrigerant, and discharges the gas refrigerant. The oil separator 6 separates the oil in the compressed refrigerant discharged from the compressor 5 and returns it to the compressor 5. The check valve 7 prevents the backflow of the compressed refrigerant.

The four-way valve 8 is a valve in which two positions are selected: a heating operation mode in which the compressed refrigerant discharged from the compressor 5 is sent to the water heat exchanger 9, and a cooling operation mode in which the compressed refrigerant is sent to the air cooling heat exchanger 12. In FIG. 1, the four-way valve 8 is in the heating operation mode position.

The water heat exchanger 9 is a heat exchanger that functions as a condenser by condensing the compressed refrigerant in the heating operation mode and as an evaporator that vaporizes the condensed refrigerant in the cooling operation mode. Then, the heat of condensation or the heat of vaporization heats or cools the water flowing through the water system portion 3 as described later to generate hot water for heating, hot water or hot water for hot water supply, or cold water for cooling.

The first refrigeration cycle system R1 has a first water heat exchanger 9A, and the second refrigeration cycle system R2 has a second water heat exchanger 9B.

The receiver 10 is a tank that stores a predetermined amount of condensed liquid refrigerant. The electronic expansion valve 11 reduces the pressure of the condensed refrigerant to promote vaporization. The air-cooled heat exchanger 12 is supplied with outside air by a cooling fan 12a. The air-cooled heat exchanger 12 is a heat exchanger that functions as an evaporator that vaporizes the condensed refrigerant in the heating operation mode and functions as a condenser that condenses the compressed refrigerant in the cooling operation mode. The gas-liquid separator 13 separates the refrigerant before being sucked into the compressor 5 into gas-liquid and causes the compressor 5 to suck only the gas refrigerant.

The water system portion 3 includes a water inlet portion 15, a water pump 16, a water outlet portion 17, and a water pipe 18. A water pump 16 is installed in the water pipe 18 extending from the water inlet portion 15.

Next, the configuration of the water pipe 18 according to the present embodiment will be described with reference to FIGS. 2 and 3.
The water pipe 18 is composed of, for example, water pipes 18a to 18e. One four-way valve 20 is installed in the water pipe 18. The four-way valve 20 has a first connection port 21, a second connection port 22, a third connection port 23, and a fourth connection port 24.

The four-way valve 20 has a configuration that can be switched to the first mode or the second mode. In the first mode, as shown in FIG. 2, the first connection port 21 and the second connection port 22 can be distributed, and the third connection port 23 and the fourth connection port 24 can be distributed. In the second mode, as shown in FIG. 3, the first connection port 21 and the third connection port 23 can be distributed, and the second connection port 22 and the fourth connection port 24 can be distributed.

The water pipe 18a is connected to the first connection port 21 of the four-way valve 20, and at the first connection port 21, water flowing through the water pipe 18a sent from the supply source always flows into the four-way valve 20.

The water pipe 18d is connected to the fourth connection port 24 of the four-way valve 20, and at the fourth connection port 24, the water flowing through the first and second water heat exchangers 9A and 9B always flows out from the four-way valve 20. , Sent to the supplier.

One end of the water pipe 18b is connected to the second connection port 22 of the four-way valve 20, and the other end is connected to the connection port on one end side of the first water heat exchanger 9A. When the four-way valve 20 is in the first mode in which the first connection port 21 and the second connection port 22 can flow, in the water pipe 18b, water is supplied from the second connection port 22 of the four-way valve 20 to the first water heat exchanger 9A. Is sent. When the four-way valve 20 is in the second mode in which the second connection port 22 and the fourth connection port 24 can flow, in the water pipe 18b, water is supplied from the first water heat exchanger 9A to the second connection port 22 of the four-way valve 20. Is sent.

One end of the water pipe 18e is connected to the connection port on the other end side of the first water heat exchanger 9A, and the other end is connected to the connection port on the one end side of the second water heat exchanger 9B.

One end of the water pipe 18c is connected to the third connection port 23, and the other end is connected to the connection port on the other end side of the second water heat exchanger 9B. When the four-way valve 20 is in the first mode in which the third connection port 23 and the fourth connection port 24 can be distributed, in the water pipe 18c, water is supplied from the second water heat exchanger 9B to the third connection port 23 of the four-way valve 20. Is sent. When the four-way valve 20 is in the second mode in which the first connection port 21 and the third connection port 23 can be distributed, in the water pipe 18c, water is supplied from the third connection port 23 of the four-way valve 20 to the second water heat exchanger 9B. Is sent.

When the four-way valve 20 is switched to the first mode, water flowing through the water pipe 18a flows in at the first connection port 21, water flows from the first connection port 21 to the second connection port 22, and then the second Water is supplied from the connection port 22 to the first water heat exchanger 9A. Further, in the first mode, the water flowing through the second water heat exchanger 9B passes through the first water heat exchanger 9A and the second water heat exchanger 9B in order, flows in from the third connection port 23, and is connected to the third. After the water flows from the port 23 to the fourth connection port 24, the water flows out from the fourth connection port 24 through the water pipe 18d.

When the four-way valve 20 is switched to the second mode, water flowing through the water pipe 18a flows in at the first connection port 21, water flows from the first connection port 21 to the third connection port 23, and then the third Water is supplied from the connection port 23 to the second water heat exchanger 9B. Further, in the second mode, the water flowing through the first water heat exchanger 9A passes through the second water heat exchanger 9B and the first water heat exchanger 9A in order, flows in from the second connection port 22, and is connected to the second. After the water flows from the port 22 to the fourth connection port 24, the water flows out from the fourth connection port 24 through the water pipe 18d.

By switching the four-way valve 20, it is possible to change the water flow direction of the water pipe 18 connected to the first and second water heat exchangers 9A and 9B. Therefore, by switching the four-way valve 20 according to the switching between the cooling operation and the heating operation of the first and second refrigeration cycle systems R1 and R2, the flow direction of the refrigerant in the first and second refrigeration cycle systems R1 and R2 can be determined. The water flow direction of the water pipe 18 can always be countercurrent. Further, regardless of the switching of the four-way valve 20, water always flows in the water pipe 18, and there is no system in which water does not flow. Therefore, when changing the water flow direction of the water pipes 18 connected to the first and second water heat exchangers 9A and 9B, the water flow direction can be quickly switched and problems are less likely to occur. be able to.

Further, since the number of installed four-way valves 20 is one, which is smaller than the number of installed three-way valves, the number of parts can be reduced. Further, when a three-way valve is installed, a plurality of three-way valves need to operate, whereas one four-way valve 20 only needs to operate, so that a switching problem due to an operation error is unlikely to occur.

The four-way valve 20 is installed inside the unit body (housing) of the chiller unit 1. In this case, since the four-way valve 20 is installed inside the unit body, the water inlet portion 15 and the water outlet portion 17 are connected to the external water pipes, respectively. As a result, by simply connecting the chiller unit 1 to the external water pipe, the flow direction of the refrigerant in the first and second refrigeration cycle systems R1 and R2 and the water flow direction in the water pipe 18 can always be countercurrent. A possible system can be constructed.

In the present embodiment, the four-way valve 20 is not limited to the case where it is installed inside the unit main body, and the four-way valve 20 may be installed outside the unit main body (housing) of the chiller unit 1. In this case, one end of the unit body is connectable to an external water pipe, and the other end is a water pipe 18b connected to the first water heat exchanger 9A, the first water heat exchanger 9A and the second water heat. A water pipe 18e connecting the exchanger 9B and a water pipe 18c having one end connected to the second water heat exchanger 9B and the other end connectable to an external water pipe are installed. The four-way valve 20 is connected to the water pipes 18b and 18c installed inside the main body of these units, and by installing the water pipes 18a and 18d having the above-described configuration, the chiller unit 1 according to the present embodiment is installed. Is configured. As a result, it is possible to configure a system in which the flow direction of the refrigerant in the first and second refrigeration cycle systems R1 and R2 and the flow direction of water in the water pipe 18 can always be countercurrent. Since the four-way valve 20 is not installed inside the unit body, the unit body can be applied to a configuration in which the water flow direction of the water pipe 18 does not need to be switched.

As shown in FIG. 1, the chiller unit 1 according to the present embodiment may include a temperature detection unit 31, a pressure detection unit 32, and a control unit 33.

The temperature detection unit 31 is installed on the upstream side and / or downstream side of the connection ports of the first and second water heat exchangers 9A and 9B in the first and second refrigeration cycle systems R1 and R2, and the first and first The temperature of the refrigerant flowing through the second refrigeration cycle system R1 and R2 is detected.

The pressure detection unit 32 is installed on the suction side and the discharge side of the compressor 5 in the first and second refrigeration cycle systems R1 and R2, respectively, and measures the pressure of the refrigerant flowing through the first and second refrigeration cycle systems R1 and R2. To detect.

The control unit 33 switches the four-way valve 20 based on the temperature detected by the temperature detection unit 31. The first and second refrigeration cycle systems R1 are based on the temperature of the refrigerant flowing into the first and second water heat exchangers 9A and 9B or the refrigerant flowing out of the first and second water heat exchangers 9A and 9B. , R2 determines whether it is a cooling operation or a heating operation.

Since the first and second water heat exchangers 9A and 9B function as evaporators during the cooling operation, if the detected temperature is lower than a predetermined threshold value, it can be determined that the cooling operation is performed, and the four-way valve 20 To switch to the mode corresponding to the cooling operation. Since the first and second water heat exchangers 9A and 9B function as condensers during the heating operation, if the detected temperature is higher than a predetermined threshold, it can be determined that the heating operation is performed, and the four-way valve 20 To switch to the mode corresponding to the heating operation. As a result, in both the cooling operation and the heating operation, in the first and second water heat exchangers 9A and 9B, the flow direction of the refrigerant in the first and second refrigeration cycle systems R1 and R2 and the flow of water in the water pipe 18 The direction is countercurrent.

Further, the control unit 33 determines the success or failure of switching the four-way valve 20 based on the pressure detected by the pressure detection unit 32. If the four-way valve 20 is not switched correctly, in the first and second water heat exchangers 9A and 9B, the flow direction of the refrigerant in the first and second refrigeration cycle systems R1 and R2 and the flow direction of water in the water pipe 18. Is a parallel flow, so that the heat exchange efficiency in the first and second water heat exchangers 9A and 9B is lowered. Therefore, for example, when the pressure detection unit 32 detects the pressure of the refrigerant sucked into the compressor 5 and the pressure of the refrigerant discharged from the compressor 5, and the pressure difference becomes lower than a predetermined threshold value, the four-way valve 20 is correctly used. Judge that it has not been switched. On the other hand, if the pressure difference exceeds a predetermined threshold value, it is determined that the four-way valve 20 is properly switched.

The control unit 33 is composed of, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a computer-readable storage medium, and the like. As an example, a series of processes for realizing various functions are stored in a storage medium or the like in the form of a program, and the CPU reads this program into a RAM or the like to execute information processing / arithmetic processing. As a result, various functions are realized. The program is installed in a ROM or other storage medium in advance, is provided in a state of being stored in a computer-readable storage medium, or is distributed via a wired or wireless communication means. Etc. may be applied. Computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, semiconductor memories, and the like.

According to the present embodiment, in the first and second refrigeration cycle systems R1 and R2, the temperature detection unit 31 installed on the upstream side or the downstream side of the connection ports of the first and second water heat exchangers 9A and 9B. The temperature of the refrigerant flowing through the first and second refrigeration cycle systems R1 and R2 is detected, and the four-way valve 20 is switched based on the detected temperature. The temperature of the refrigerant flowing upstream or downstream of the connection ports of the first and second water heat exchangers 9A and 9B according to the switching between the cooling operation and the heating operation of the first and second refrigeration cycle systems R1 and R2. Is changed. Therefore, the four-way valve 20 is automatically switched according to the detected refrigerant temperature, so that the refrigerant flow direction of the first and second refrigeration cycle systems R1 and R2 and the water flow direction of the water pipe 18 can be changed. It can always be countercurrent.

Further, the pressure detection units 32 installed in the first and second refrigeration cycle systems R1 and R2 detect the pressure of the refrigerant flowing through the first and second refrigeration cycle systems R1 and R2, and based on the detected pressure. , The success or failure of switching the four-way valve 20 is determined. Therefore, when the four-way valve 20 is automatically switched, it can be determined whether or not the four-way valve 20 is correctly switched.

The chiller unit 1 configured as described above operates as follows. In the following, an example will be described in which the four-way valve 20 switches to the first mode shown in FIG. 2 during the heating operation, and the four-way valve 20 switches to the second mode shown in FIG. 3 during the cooling operation.

First, the operation during the heating operation will be described.
During the heating operation, the four-way valves 8 of the first and second refrigeration cycle systems R1 and R2 are in the position of the heating operation mode shown in FIG.

Then, at least one compressor 5 is activated. The high-temperature and high-pressure compressed refrigerant compressed by the compressor 5 is separated by an oil separator 6 and passed through a four-way valve 8 to any or all of the first and second water heat exchangers 9A and 9B. It flows. At this time, the compressed refrigerant exchanges heat with the water flowing through the water pipe 18 of the water system unit 3. Further, the temperature is detected by the temperature detection unit 31, and the four-way valve 20 switches to the first mode.

That is, the compressed refrigerant compressed by the compressor 5 of the first refrigeration cycle system R1 flows to the first water heat exchanger 9A and exchanges heat with the water flowing through the water pipe 18, and the compressor 5 of the second refrigeration cycle system R2 The compressed refrigerant compressed by the above flows into the second water heat exchanger 9B and exchanges heat with the water flowing through the water pipe 18.

That is, in the first refrigeration cycle system R1 and the second refrigeration cycle system R2, heat exchange between the refrigerant and water is individually performed by the first water heat exchanger 9A and the second water heat exchanger 9B, respectively. The water that has been heat-exchanged with the high-temperature compressed refrigerant in the first and second water heat exchangers 9A and 9B becomes hot water or hot water, and is supplied from the water outlet portion 17 to a predetermined heating location or hot water supply location.

When the four-way valve 20 is switched to the first mode, water flowing through the water pipe 18a flows into the first connection port 21, water flows from the first connection port 21 to the second connection port 22, and then the second connection port 22. Water is supplied from 22 to the first water heat exchanger 9A. Further, in the first mode, water flows in the order of the first water heat exchanger 9A and the second water heat exchanger 9B, and the water flowing through the second water heat exchanger 9B flows in from the third connection port 23, and the first 3 After water flows from the connection port 23 to the fourth connection port 24, water flows out from the fourth connection port 24 via the water pipe 18d. In the first and second water heat exchangers 9A and 9B, the flow direction of the refrigerant in the first and second refrigeration cycle systems R1 and R2 and the flow direction of water in the water pipe 18 are countercurrent.

Further, the compressed refrigerant that has exchanged heat with water in the first and second water heat exchangers 9A and 9B is condensed and liquefied, passes through the electronic expansion valve 11 via the receiver 10, and the pressure is reduced here to provide air-cooled heat. It flows through the exchanger 12 and vaporizes by exchanging heat with air to become a gas refrigerant, which is sucked into the compressor 5 again via the four-way valve 8 and the gas-liquid separator 13.

Next, the operation during the cooling operation will be described.
During the cooling operation, the four-way valves 8 of the first and second refrigeration cycle systems R1 and R2 are changed from the directions shown in FIG. 1 to be in the cooling operation mode position. Therefore, the high-temperature and high-pressure compressed refrigerant compressed by the compressor 5 flows through the four-way valve 8 to the air-cooled heat exchanger 12, and the outside air is supplied by the cooling fan 12a to exchange heat with the air to condense and liquefy. .. The generated condensed refrigerant flows through the receiver 10 to any or all of the first and second water heat exchangers 9A and 9B. At this time, the condensed refrigerant exchanges heat with the water flowing through the water pipe 18 of the water system unit 3 and vaporizes. Further, the temperature is detected by the temperature detection unit 31, and the four-way valve 20 switches to the second mode.

In this way, the water that has been heat-exchanged with the low-temperature refrigerant in the first and second water heat exchangers 9A and 9B becomes cold water and is supplied from the water outlet portion 17 to a predetermined cooling location.

When the four-way valve 20 is switched to the second mode, water flowing through the water pipe 18a flows in at the first connection port 21, water flows from the first connection port 21 to the third connection port 23, and then the third connection port 23. Water is supplied from 23 to the second water heat exchanger 9B. Further, in the second mode, water flows in the order of the second water heat exchanger 9B and the first water heat exchanger 9A, and the water flowing through the second water heat exchanger 9B flows in from the second connection port 22 and is second. After the water flows from the 2 connection port 22 to the 4th connection port 24, the water flows out from the 4th connection port 24 to the outside through the water pipe 18d. In the first and second water heat exchangers 9A and 9B, the flow direction of the refrigerant in the first and second refrigeration cycle systems R1 and R2 and the flow direction of water in the water pipe 18 are countercurrent.

Further, the gas refrigerant vaporized by heat exchange with water in the first and second water heat exchangers 9A and 9B is sucked into the compressor 5 again through the four-way valve 8 and the gas-liquid separator 13.

Next, a modified example of the chiller unit 1 according to the embodiment of the present invention will be described with reference to FIG. The configuration of the first refrigeration cycle system R1 and the second refrigeration cycle system R2 in the chiller unit 1 is the same as that of the above-described embodiment. In addition, the description of the configuration and the action and effect overlapping with the above-described embodiment will be omitted.

In the configuration according to the above-described embodiment, the water flowing through the first water heat exchanger 9A and the second water heat exchanger 9B is changed by switching the four-way valve 20, and as shown in FIG. 2, the first water heat exchanger 9A Is first, or as shown in FIG. 3, the second water heat exchanger 9B comes first, and the order of water flow is changed.

On the other hand, when a plurality of first and second water heat exchangers 9A and 9B are arranged in series, the first water heat exchanger 9A or the second water heat exchange is performed regardless of the switching of the four-way valve 20. In some cases, a configuration in which the vessel 9B always comes first is required.

In the above-described embodiment, only one set of the four-way valve 20 and the water pipes 18a to 18e is installed for the first water heat exchanger 9A and the second water heat exchanger 9B. On the other hand, in the water pipe 18 in this modification, unlike the above-described embodiment, the four-way valve 20 and the water pipe 18 are provided in one set for each of the first refrigeration cycle system R1 and the second refrigeration cycle system R2. It will be installed one by one.

By switching each of the four-way valves 20, it is possible to change the water flow direction of the water pipe 18 connected to the first and second water heat exchangers 9A and 9B. Therefore, by switching each of the four-way valves 20 according to the switching between the cooling operation and the heating operation of the first and second refrigeration cycle systems R1 and R2, the flow direction of the refrigerant in the first and second refrigeration cycle systems R1 and R2 And the water flow direction of the water pipe 18 can always be countercurrent. Further, as shown in FIG. 4, when a plurality of first and second water heat exchangers 9A and 9B are arranged in series, the first water heat exchanger 9A is used regardless of the switching of the four-way valve 20. It can always be the first configuration.

1: Chiller unit 3: Water system part 5: Compressor 6: Oil separator 7: Check valve 8: Four-way valve 9: Water heat exchanger 9A: First water heat exchanger 9B: Second water heat exchanger 10: Receiver 11: Electronic expansion valve 12: Air-cooled heat exchanger 12a: Cooling fan 13: Gas-liquid separator 15: Water inlet 16: Water pump 17: Water outlet 18, 18a, 18b, 18c, 18d, 18e: Water piping 20: Four-way valve 21: First connection port 22: Second connection port 23: Third connection port 24: Fourth connection port 31: Temperature detection unit 32: Pressure detection unit 33: Control unit R1: First refrigeration cycle system R2 : Second refrigeration cycle system

Claims (5)

A refrigeration cycle system that has a water heat exchanger and circulates refrigerant,
A water pipe connected to the water heat exchanger and through which water flows,
A four-way valve installed in the water pipe and having a first connection port, a second connection port, a third connection port, and a fourth connection port.
With
The water flowing through the water pipe at the first connection port always flows into the four-way valve, and the water flowing through the water heat exchanger at the fourth connection port always flows out from the four-way valve.
The second connection port and the connection port on one end side of the water heat exchanger are connected by the water pipe, and the third connection port and the connection port on the other end side of the water heat exchanger are connected by the water pipe. Connected
The four-way valve has a first mode in which the first connection port and the second connection port can be distributed, and the third connection port and the fourth connection port can be distributed, or the first connection port. A chiller unit having a configuration in which the third connection port can be distributed and the second mode can be switched to a second mode in which the second connection port and the fourth connection port can be distributed. The chiller unit according to claim 1, wherein the four-way valve is installed inside the unit body. The chiller unit according to claim 1, wherein the four-way valve is installed outside the unit body and is connected to the water pipe installed inside the unit body. In the refrigeration cycle system, a temperature detection unit installed on the upstream side or the downstream side of the connection port of the water heat exchanger and detecting the temperature of the refrigerant flowing through the refrigeration cycle system.
A control unit that switches the four-way valve based on the temperature detected by the temperature detection unit, and
The chiller unit according to any one of claims 1 to 3. A pressure detection unit installed in the refrigeration cycle system and detecting the pressure of the refrigerant flowing through the refrigeration cycle system.
The chiller unit according to claim 4, wherein the control unit determines the success or failure of switching of the four-way valve based on the pressure detected by the pressure detection unit.

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