WO2018116404A1

WO2018116404A1 - Heat pump utilization equipment

Info

Publication number: WO2018116404A1
Application number: PCT/JP2016/088107
Authority: WO
Inventors: 康巨鈴木; 一隆鈴木; 博和南迫; 服部　太郎
Original assignee: 三菱電機株式会社
Priority date: 2016-12-21
Filing date: 2016-12-21
Publication date: 2018-06-28
Also published as: EP3358273B1; EP3358273A4; US20190301750A1; CN110073152A; EP3358273A1; JP6664516B2; JPWO2018116404A1; CN110073152B

Abstract

This heat pump utilization equipment comprises a refrigerant circuit, a heat medium circuit, and a heat exchanger which performs heat exchange between a refrigerant and a heat medium. The main circuit of the heat medium circuit has a branch section and a merging section. A pressure protection device and a refrigerant leakage detection device are connected to the main circuit. The pressure protection device is connected to a connection section which is located between the heat exchanger and one of the branch section and the merging section in the main circuit. A first shut-off device capable of shutting off the flow from the heat exchanger to the connection section is provided between the heat exchanger and the connection section in the main circuit. A second shut-off device capable of shutting off the flow from the heat exchanger to the other of the branch section and the merging section is provided between the heat exchanger and said section in the main circuit.

Description

Heat pump equipment

The present invention relates to a heat pump device having a refrigerant circuit and a heat medium circuit.

Patent Document 1 describes an outdoor unit of a heat pump cycle device using a combustible refrigerant. This outdoor unit includes a refrigerant circuit in which a compressor, an air heat exchanger, a throttling device, and a water heat exchanger are connected by piping, and excess water pressure in the water circuit for supplying water heated by the water heat exchanger. And a pressure relief valve for preventing the ascent. As a result, even when the partition separating the refrigerant circuit and the water circuit is destroyed in the water heat exchanger and the flammable refrigerant is mixed into the water circuit, the flammable refrigerant is discharged to the outside through the pressure relief valve. Can do.

JP 2013-167398 A

In heat pump equipment such as a heat pump cycle device, generally, a pressure relief valve for a water circuit is provided in an indoor unit. There are various combinations of the outdoor unit and the indoor unit in the heat pump device. Not only the outdoor unit and the indoor unit of the same manufacturer are combined, but also the outdoor unit and the indoor unit of different manufacturers may be combined. Therefore, the outdoor unit described in Patent Document 1 may be combined with an indoor unit provided with a pressure relief valve.

However, in this case, when the refrigerant leaks into the water circuit, the refrigerant mixed in the water in the water circuit is discharged not only from the pressure relief valve provided in the outdoor unit but also from the pressure relief valve provided in the indoor unit. There is a case. Therefore, there existed a subject that a refrigerant | coolant might leak in a room | chamber interior via a water circuit.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a heat pump-utilizing device that can prevent the refrigerant from leaking into the room.

A heat pump utilization device according to the present invention includes a refrigerant circuit that circulates a refrigerant, a heat medium circuit that circulates a heat medium, and a heat exchanger that performs heat exchange between the refrigerant and the heat medium. The circuit has a main circuit that passes through the heat exchanger, and the main circuit is provided at a downstream end of the main circuit, and a branch unit to which a plurality of branch circuits branching from the main circuit are connected. A merging portion provided at an upstream end of the main circuit and connected to the plurality of branch circuits merging with the main circuit. The main circuit includes a pressure protection device and refrigerant leakage detection. And the pressure protection device is connected to a connection part located between the heat exchanger and one of the branch part or the junction part in the main circuit, Between the heat exchanger and the connection part of the main circuit, the heat A first shut-off device capable of shutting off a flow from the exchanger toward the connection portion is provided, and the heat exchanger is disposed between the heat exchanger and the other of the branch portion or the junction portion in the main circuit. A second shutoff device capable of shutting off the flow from the exchanger toward the other side is provided.

According to the present invention, even if the refrigerant leaks into the heat medium circuit, the flow of the refrigerant mixed in the heat medium can be blocked by the blocking device. Therefore, the refrigerant can be prevented from leaking into the room from the pressure protection device.

It is a circuit diagram which shows schematic structure of the heat pump utilization apparatus which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows schematic structure of the heat pump utilization apparatus which concerns on the modification of Embodiment 1 of this invention. It is explanatory drawing which shows the example of the arrangement position of the refrigerant | coolant leak detection apparatus 98 in the heat pump utilization apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the example of the arrangement position of the refrigerant | coolant leak detection apparatus 98 in the heat pump utilization apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the example of the arrangement position of the refrigerant | coolant leak detection apparatus 98 in the heat pump utilization apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the example of the arrangement position of the refrigerant | coolant leak detection apparatus 98 in the heat pump utilization apparatus which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows schematic structure of the heat pump utilization apparatus which concerns on Embodiment 2 of this invention.

Embodiment 1 FIG.
The heat pump utilization apparatus which concerns on Embodiment 1 of this invention is demonstrated. FIG. 1 is a circuit diagram showing a schematic configuration of a heat pump utilizing device according to the present embodiment. In the present embodiment, a heat pump hot water supply / room heating device 1000 is illustrated as an example of a heat pump using device. In the following drawings including FIG. 1, the dimensional relationship and shape of each component may differ from the actual ones.

As shown in FIG. 1, the heat pump hot water supply and heating device 1000 includes a refrigerant circuit 110 that circulates a refrigerant and a water circuit 210 that circulates water. In addition, the heat pump hot water supply and heating device 1000 includes an outdoor unit 100 installed outdoors (for example, outdoors) and an indoor unit 200 installed indoors. The indoor unit 200 is installed, for example, in a storage space such as a storage room in a building, in addition to a kitchen, a bathroom, and a laundry room.

The refrigerant circuit 110 includes a compressor 3, a refrigerant flow switching device 4, a load side heat exchanger 2, a first pressure reducing device 6, an intermediate pressure receiver 5, a second pressure reducing device 7, and a heat source side heat exchanger 1. Are sequentially connected in a ring shape. In the refrigerant circuit 110 of the heat pump hot water supply and heating device 1000, the refrigerant flows in the reverse direction with respect to the normal operation (for example, heating hot water supply operation) for heating the water flowing in the water circuit 210 and the normal operation, and the heat source side heat exchanger 1 The defrosting operation for performing the defrosting is possible.

The compressor 3 is a fluid machine that compresses sucked low-pressure refrigerant and discharges it as high-pressure refrigerant. The compressor 3 of this example includes an inverter device and the like, and can change the capacity (the amount of refrigerant sent out per unit time) by arbitrarily changing the drive frequency.

The refrigerant flow switching device 4 switches the flow direction of the refrigerant in the refrigerant circuit 110 between the normal operation and the defrosting operation. For example, a four-way valve is used as the refrigerant flow switching device 4.

The load-side heat exchanger 2 is a water-refrigerant heat exchanger that performs heat exchange between the refrigerant flowing through the refrigerant circuit 110 and the water flowing through the water circuit 210. As the load-side heat exchanger 2, for example, a plate heat exchanger is used. The load-side heat exchanger 2 is a thin plate that separates the refrigerant flow path through which the refrigerant flows as part of the refrigerant circuit 110, the water flow path through which water flows as part of the water circuit 210, and the refrigerant flow path from the water flow path. And a partition wall. The load-side heat exchanger 2 functions as a condenser (heat radiator) that heats water during normal operation, and functions as an evaporator (heat absorber) during defrosting operation.

The first decompression device 6 adjusts the flow rate of the refrigerant, and for example, adjusts the pressure of the refrigerant flowing through the load-side heat exchanger 2. The intermediate pressure receiver 5 is located between the first decompression device 6 and the second decompression device 7 in the refrigerant circuit 110 and stores excess refrigerant. A suction pipe 11 connected to the suction side of the compressor 3 passes inside the intermediate pressure receiver 5. In the intermediate pressure receiver 5, heat exchange between the refrigerant passing through the suction pipe 11 and the refrigerant in the intermediate pressure receiver 5 is performed. For this reason, the intermediate pressure receiver 5 has a function as an internal heat exchanger in the refrigerant circuit 110. The second decompression device 7 adjusts the flow rate of the refrigerant to adjust the pressure. The first decompression device 6 and the second decompression device 7 of this example are electronic expansion valves that can change the opening degree based on an instruction from the control device 101 described later.

The heat source side heat exchanger 1 is an air-refrigerant heat exchanger that performs heat exchange between the refrigerant flowing through the refrigerant circuit 110 and outdoor air blown by an outdoor blower (not shown) or the like. The heat source side heat exchanger 1 functions as an evaporator (heat absorber) during normal operation and functions as a condenser (heat radiator) during defrosting operation.

As the refrigerant circulating in the refrigerant circuit 110, for example, a slightly flammable refrigerant such as R1234yf and R1234ze (E) or a strong flammable refrigerant such as R290 and R1270 is used. These refrigerants may be used as a single refrigerant, or may be used as a mixed refrigerant in which two or more kinds are mixed. Hereinafter, a refrigerant having a flammability that is equal to or higher than the slight combustion level (for example, 2 L or more according to the ASHRAE 34 classification) may be referred to as “flammable refrigerant” or “flammable refrigerant”. Further, as the refrigerant circulating in the refrigerant circuit 110, nonflammable refrigerants such as R407C and R410A having nonflammability (for example, 1 in the classification of ASHRAE 34) may be used. These refrigerants have a density higher than that of air at atmospheric pressure (for example, the temperature is room temperature (25 ° C.)). Further, as the refrigerant circulating in the refrigerant circuit 110, a toxic refrigerant such as R717 (ammonia) can be used.

The refrigerant circuit 110 including the compressor 3, the refrigerant flow switching device 4, the load side heat exchanger 2, the first pressure reducing device 6, the intermediate pressure receiver 5, the second pressure reducing device 7, and the heat source side heat exchanger 1 are all outdoor. It is accommodated in the machine 100.

The outdoor unit 100 mainly controls the operation of the refrigerant circuit 110 (for example, the compressor 3, the refrigerant flow switching device 4, the first decompression device 6, the second decompression device 7, an outdoor blower not shown). A control device 101 is provided. The control device 101 has a microcomputer equipped with a CPU, ROM, RAM, I / O port, and the like. The control device 101 can communicate with a control device 201 and an operation unit 202 described later via a control line 102.

Next, an example of the operation of the refrigerant circuit 110 will be described. In FIG. 1, the flow direction of the refrigerant during normal operation in the refrigerant circuit 110 is indicated by solid line arrows. During normal operation, the refrigerant flow path switching device 4 switches the refrigerant flow path as indicated by solid arrows, and the refrigerant circuit 110 is configured such that high-temperature and high-pressure refrigerant flows into the load-side heat exchanger 2.

The high-temperature and high-pressure gas refrigerant discharged from the compressor 3 flows into the refrigerant flow path of the load-side heat exchanger 2 via the refrigerant flow switching device 4. During normal operation, the load side heat exchanger 2 functions as a condenser. That is, in the load side heat exchanger 2, heat exchange between the refrigerant flowing through the refrigerant flow path and the water flowing through the water flow path is performed, and the condensation heat of the refrigerant is radiated to the water. Thereby, the refrigerant | coolant which flows through the refrigerant | coolant flow path of the load side heat exchanger 2 is condensed, and turns into a high voltage | pressure liquid refrigerant. Moreover, the water which flows through the water flow path of the load side heat exchanger 2 is heated by the heat radiation from the refrigerant.

The high-pressure liquid refrigerant condensed in the load-side heat exchanger 2 flows into the first decompression device 6 and is slightly decompressed to become a two-phase refrigerant. The two-phase refrigerant flows into the intermediate pressure receiver 5 and is cooled by heat exchange with the low-pressure gas refrigerant flowing through the suction pipe 11 to become a liquid refrigerant. This liquid refrigerant flows into the second decompression device 7 and is decompressed to become a low-pressure two-phase refrigerant. The low-pressure two-phase refrigerant flows into the heat source side heat exchanger 1. During normal operation, the heat source side heat exchanger 1 functions as an evaporator. That is, in the heat source side heat exchanger 1, heat exchange is performed between the refrigerant circulating in the interior and the outdoor air blown by the outdoor blower, and the heat of evaporation of the refrigerant is absorbed from the outdoor air. Thereby, the refrigerant flowing into the heat source side heat exchanger 1 evaporates to become a low-pressure gas refrigerant. The low-pressure gas refrigerant flows into the suction pipe 11 via the refrigerant flow switching device 4. The low-pressure gas refrigerant flowing into the suction pipe 11 is heated by heat exchange with the refrigerant in the intermediate-pressure receiver 5 and is sucked into the compressor 3. The refrigerant sucked into the compressor 3 is compressed into a high-temperature and high-pressure gas refrigerant. In normal operation, the above cycle is continuously repeated.

Next, an example of the operation during the defrosting operation will be described. In FIG. 1, the flow direction of the refrigerant during the defrosting operation in the refrigerant circuit 110 is indicated by a broken line arrow. During the defrosting operation, the refrigerant channel 110 is configured such that the refrigerant channel is switched by the refrigerant channel switching device 4 as indicated by the broken-line arrows, and the high-temperature and high-pressure refrigerant flows into the heat source side heat exchanger 1.

The high-temperature and high-pressure gas refrigerant discharged from the compressor 3 flows into the heat source side heat exchanger 1 through the refrigerant flow switching device 4. During the defrosting operation, the heat source side heat exchanger 1 functions as a condenser. That is, in the heat source side heat exchanger 1, the heat of condensation of the refrigerant flowing inside is radiated to the frost attached to the surface of the heat source side heat exchanger 1. Thereby, the refrigerant | coolant which distribute | circulates the inside of the heat source side heat exchanger 1 is condensed, and turns into a high voltage | pressure liquid refrigerant. Moreover, the frost adhering to the surface of the heat source side heat exchanger 1 is melted by heat radiation from the refrigerant.

The high-pressure liquid refrigerant condensed in the heat source side heat exchanger 1 becomes a low-pressure two-phase refrigerant via the second decompression device 7, the intermediate pressure receiver 5, and the first decompression device 6, and the refrigerant in the load-side heat exchanger 2. It flows into the flow path. During the defrosting operation, the load side heat exchanger 2 functions as an evaporator. That is, in the load side heat exchanger 2, heat exchange between the refrigerant flowing through the refrigerant flow path and the water flowing through the water flow path is performed, and the evaporation heat of the refrigerant is absorbed from the water. Thereby, the refrigerant | coolant which flows through the refrigerant | coolant flow path of the load side heat exchanger 2 evaporates, and becomes a low voltage | pressure gas refrigerant. This gas refrigerant is sucked into the compressor 3 via the refrigerant flow switching device 4 and the suction pipe 11. The refrigerant sucked into the compressor 3 is compressed into a high-temperature and high-pressure gas refrigerant. In the defrosting operation, the above cycle is continuously repeated.

Next, the water circuit 210 will be described. The water circuit 210 of the present embodiment is a closed circuit that circulates water. In FIG. 1, the flow direction of water is represented by a thick white arrow. The water circuit 210 is configured by connecting a water circuit on the outdoor unit 100 side and a water circuit on the indoor unit 200 side. The water circuit 210 includes a main circuit 220, a branch circuit 221 that constitutes a hot water supply circuit, and a branch circuit 222 that constitutes a part of the heating circuit. The main circuit 220 constitutes a part of a closed circuit. The

branch circuits

221 and 222 are branched and connected to the main circuit 220, respectively. The

branch circuits

221 and 222 are provided in parallel with each other. The branch circuit 221 forms a closed circuit together with the main circuit 220. The branch circuit 222 forms a closed circuit together with the main circuit 220, the heating device 300 connected to the branch circuit 222, and the like. The heating device 300 is provided indoors separately from the indoor unit 200. As the heating device 300, a radiator or a floor heating device is used.

In this embodiment, water is used as an example of the heat medium flowing through the water circuit 210, but other liquid heat medium such as brine can be used as the heat medium.

The main circuit 220 has a configuration in which a strainer 56, a flow switch 57, a load-side heat exchanger 2, a booster heater 54, a pump 53, and the like are connected via a water pipe. A drain outlet 62 for draining the water in the water circuit 210 is provided in the middle of the water pipe constituting the main circuit 220. The downstream end of the main circuit 220 is connected to an inlet of a three-way valve 55 (an example of a branching portion) having one inlet and two outlets. In the three-way valve 55, the

branch circuits

221 and 222 are branched from the main circuit 220. The upstream end of the main circuit 220 is connected to the junction unit 230. In the junction unit 230, the

branch circuits

221 and 222 join the main circuit 220. The water circuit 210 from the junction 230 to the three-way valve 55 via the load side heat exchanger 2 and the like becomes the main circuit 220.

The load side heat exchanger 2 of the main circuit 220 is provided in the outdoor unit 100. Devices other than the load-side heat exchanger 2 in the main circuit 220 are provided in the indoor unit 200. That is, the main circuit 220 of the water circuit 210 is provided across the outdoor unit 100 and the indoor unit 200. A part of the main circuit 220 is provided in the outdoor unit 100, and another part of the main circuit 220 is provided in the indoor unit 200. The outdoor unit 100 and the indoor unit 200 are connected via two

connection pipes

211 and 212 that constitute a part of the main circuit 220.

The pump 53 is a device that pressurizes the water in the water circuit 210 and circulates the water circuit 210. The booster heater 54 is a device that further heats the water in the water circuit 210 when the heating capacity of the outdoor unit 100 is insufficient. The three-way valve 55 is a device for switching the flow of water in the water circuit 210. For example, the three-way valve 55 switches whether the water in the main circuit 220 is circulated on the branch circuit 221 side or the branch circuit 222 side. The strainer 56 is a device that removes the scale in the water circuit 210. The flow switch 57 is a device for detecting whether or not the flow rate of water circulating in the water circuit 210 is a certain amount or more. A flow sensor can be used in place of the flow switch 57.

A pressure relief valve 70 (an example of a pressure protection device) is connected to the booster heater 54. That is, the booster heater 54 becomes a connection part of the pressure relief valve 70 (an example of a pressure protection device). Hereinafter, the connection portion of the pressure relief valve 70 may be simply expressed as “connection portion”. The pressure relief valve 70 is a protection device that prevents an excessive increase in pressure in the water circuit 210 due to a change in the temperature of water. The pressure relief valve 70 discharges water to the outside of the water circuit 210 based on the pressure in the water circuit 210. For example, when the pressure in the water circuit 210 becomes higher than the pressure control range of the expansion tank 52 (described later), the pressure relief valve 70 is opened, and the water in the water circuit 210 is discharged from the pressure relief valve 70 to the outside. To be released. The pressure relief valve 70 is provided in the indoor unit 200. The reason why the pressure relief valve 70 is provided in the indoor unit 200 is to perform pressure protection in the water circuit 210 in the indoor unit 200.

One end of a pipe 72 serving as a water flow path branched from the main circuit 220 is connected to the casing of the booster heater 54. A pressure relief valve 70 is attached to the other end of the pipe 72. That is, the pressure relief valve 70 is connected to the booster heater 54 via the pipe 72. The booster heater 54 serves as a connection portion where the pressure relief valve 70 is connected to the main circuit 220. The highest water temperature in the main circuit 220 is in the booster heater 54. For this reason, the booster heater 54 is optimal as a connection part to which the pressure relief valve 70 is connected. Further, if the pressure relief valve 70 is connected to the

branch circuits

221, 222, the pressure relief valve 70 needs to be provided for each

branch circuit

221, 222. In the present embodiment, since the pressure relief valve 70 is connected to the main circuit 220, the number of the pressure relief valves 70 may be one.

In the middle of the pipe 72, a branch part 72a is provided. One end of a pipe 75 is connected to the branch part 72a. An expansion tank 52 is connected to the other end of the pipe 75. That is, the expansion tank 52 is connected to the booster heater 54 via the

pipes

75 and 72. The expansion tank 52 is a device for controlling the pressure change in the water circuit 210 accompanying the water temperature change within a certain range.

A shut-off device 77 is provided on the downstream side of the load-side heat exchanger 2 as a first shut-off device. The shut-off device 77 is provided in the main circuit 220 between the load-side heat exchanger 2 and the booster heater 54 (that is, the connection portion to which the pressure relief valve 70 is connected). As the shut-off device 77, an on-off valve such as an electromagnetic valve, a flow rate adjusting valve or an electronic expansion valve is used. The shut-off device 77 is in an open state during normal operation. When the shut-off device 77 is in the closed state, the shut-off device 77 blocks the flow from the load-side heat exchanger 2 toward the booster heater 54. The blocking device 77 is controlled by the control device 201 described later. If the connection part to which the pressure relief valve 70 is connected is provided between the load-side heat exchanger 2 and the junction part 230, the shut-off device 77 serves as the second shut-off device as the main circuit 220. Among these, it is provided between the load side heat exchanger 2 and the three-way valve 55 (branch part).

On the upstream side of the load-side heat exchanger 2, a shut-off device 78 is provided as a second shut-off device. The shut-off device 78 is provided between the load-side heat exchanger 2 and the junction 230 in the main circuit 220. As the shut-off device 78, a check valve that allows the flow of water from the junction 230 to the load-side heat exchanger 2 and blocks the flow from the load-side heat exchanger 2 to the junction 230 can be used. Further, as the shut-off device 78, an on-off valve such as an electromagnetic valve, a flow rate adjusting valve or an electronic expansion valve can be used. When an on-off valve is used as the shut-off device 78, the shut-off device 78 is controlled by the control device 201 described later or operates in conjunction with the shut-off device 77. If the connection part to which the pressure relief valve 70 is connected is provided between the load-side heat exchanger 2 and the merge part 230, the shut-off device 78 serves as the first shut-off device as the main circuit 220. It is provided between the load side heat exchanger 2 and the said connection part.

A refrigerant leak detection device 98 is provided on the downstream side of the shutoff device 77. The refrigerant leak detection device 98 is connected between the shut-off device 77 and the booster heater 54 (connection part) in the main circuit 220. The refrigerant leakage detection device 98 is a device that detects refrigerant leakage from the refrigerant circuit 110 to the water circuit 210. When the refrigerant leaks from the refrigerant circuit 110 to the water circuit 210, the pressure in the water circuit 210 increases. Therefore, the refrigerant leakage detection device 98 can detect the leakage of the refrigerant to the water circuit 210 based on the pressure in the water circuit 210 (pressure value or temporal change in pressure). As the refrigerant leakage detection device 98, for example, a pressure sensor or a pressure switch (high pressure switch) for detecting the pressure in the water circuit 210 is used. For example, the pressure switch may be an electric type or a mechanical type using a diaphragm. The refrigerant leak detection device 98 outputs a detection signal to the control device 201.

In this example, the shut-off

devices

77 and 78 and the refrigerant leak detection device 98 are all provided in the indoor unit 200. Thereby, since the control apparatus 201, interruption | blocking

apparatus

77, 78, and the refrigerant | coolant leakage detection apparatus 98 can be connected in the indoor unit 200 via a control line, cost reduction is attained. Any of the blocking

devices

77 and 78 and the refrigerant leakage detection device 98 may be provided in the outdoor unit 100. Thereby, since the control apparatus 101, the interruption | blocking

apparatus

77, 78, and the refrigerant | coolant leak detection apparatus 98 can be connected in the outdoor unit 100 via a control line, cost reduction is attained.

The branch circuit 221 constituting the hot water supply circuit is provided in the indoor unit 200. The upstream end of the branch circuit 221 is connected to one outlet of the three-way valve 55. The downstream end of the branch circuit 221 is connected to the merge unit 230. The branch circuit 221 is provided with a coil 61. The coil 61 is built in a hot water storage tank 51 that stores water therein. The coil 61 is a heating unit that heats the water stored in the hot water storage tank 51 by heat exchange with water (hot water) circulating through the branch circuit 221 of the water circuit 210. In addition, the hot water storage tank 51 has a built-in submerged heater 60. The submerged heater 60 is a heating means for further heating the water stored in the hot water storage tank 51.

A sanitary circuit side pipe 81 a (for example, a hot water supply pipe) connected to, for example, a shower or the like is connected to the upper part of the hot water storage tank 51. A sanitary circuit side pipe 81 b (for example, a makeup water pipe) is connected to the lower part in the hot water storage tank 51. A drainage port 63 for draining the water in the hot water storage tank 51 is provided in the lower part of the hot water storage tank 51. The hot water storage tank 51 is covered with a heat insulating material (not shown) in order to prevent the temperature of internal water from decreasing due to heat radiation to the outside. For the heat insulating material, for example, felt, cinsalate (registered trademark), VIP (Vacuum Insulation Panel), or the like is used.

The branch circuit 222 constituting a part of the heating circuit is provided in the indoor unit 200. The branch circuit 222 has an outward pipe 222a and a return pipe 222b. The upstream end of the forward pipe 222 a is connected to the other outlet of the three-way valve 55. The downstream end of the forward pipe 222a and the upstream end of the return pipe 222b are connected to the heating

circuit side pipes

82a and 82b, respectively. The downstream end of the return pipe 222b is connected to the junction 230. Thus, the forward pipe 222a and the return pipe 222b are connected to the heating device 300 via the heating

circuit side pipes

82a and 82b, respectively. The heating

circuit side pipes

82a and 82b and the heating device 300 are provided outside the indoor unit 200 although they are indoors. The branch circuit 222 constitutes a heating circuit together with the heating

circuit side pipes

82a and 82b and the heating device 300.

A pressure relief valve 301 is connected to the heating circuit side pipe 82a. The pressure relief valve 301 is a protection device that prevents an excessive increase in pressure in the water circuit 210, and has, for example, the same structure as the pressure relief valve 70. For example, when the pressure in the heating circuit side pipe 82a becomes higher than the set pressure, the pressure relief valve 301 is opened, and the water in the heating circuit side pipe 82a is discharged from the pressure relief valve 301 to the outside. The pressure relief valve 301 is provided outside the indoor unit 200 although it is indoors.

The heating device 300, the heating

circuit side pipes

82a and 82b, and the pressure relief valve 301 in the present embodiment are not part of the heat pump hot water supply and heating device 1000, but are facilities constructed by a local contractor according to the circumstances of each property. is there. For example, in an existing facility in which a boiler is used as a heat source device of the heating device 300, the heat source device may be updated to the heat pump hot water supply and heating device 1000. In such a case, if there is no particular inconvenience, the heating device 300, the heating

circuit side pipes

82a and 82b, and the pressure relief valve 301 are used as they are. Therefore, it is desirable that the heat pump hot water supply and heating apparatus 1000 can be connected to various facilities regardless of the presence or absence of the pressure relief valve 301.

The indoor unit 200 is provided with a control device 201 that mainly controls the operation of the water circuit 210 (for example, the pump 53, the booster heater 54, the three-way valve 55, the shut-off device 77, etc.). The control device 201 has a microcomputer provided with a CPU, ROM, RAM, I / O port, and the like. The control device 201 can communicate with the control device 101 and the operation unit 202. For example, when the control device 201 detects the leakage of the refrigerant to the water circuit 210 based on the detection signal from the refrigerant leakage detection device 98, the control device 201 sets the shut-off device 77 in the closed state. When the refrigerant leak detection device 98 outputs a contact signal when the refrigerant leaks, the refrigerant leak detection device 98 and the blocking device 77 may be directly connected without the control device 201 being interposed.

The operation unit 202 allows the user to perform operations and various settings of the heat pump hot water supply and heating device 1000. The operation unit 202 of this example includes a display unit 203. The display unit 203 can display various information such as the state of the heat pump hot water supply and heating device 1000. The operation unit 202 is provided on the surface of the casing of the indoor unit 200, for example.

Next, in the load side heat exchanger 2, an operation when the partition wall that separates the refrigerant flow path and the water flow path is damaged will be described. The load side heat exchanger 2 functions as an evaporator during the defrosting operation. For this reason, the partition wall of the load-side heat exchanger 2 may be damaged due to freezing of water or the like particularly during the defrosting operation. Generally, the pressure of the refrigerant flowing through the refrigerant flow path of the load-side heat exchanger 2 is higher than the pressure of water flowing through the water flow path of the load-side heat exchanger 2 in both the normal operation and the defrosting operation. For this reason, when the partition wall of the load-side heat exchanger 2 is damaged, the refrigerant in the refrigerant channel flows out into the water channel in both the normal operation and the defrosting operation, and the refrigerant is mixed into the water in the water channel. At this time, the refrigerant mixed in the water is gasified by a decrease in pressure. Moreover, the pressure in the water circuit 210 rises when refrigerant having a pressure higher than that of water mixes in the water.

The refrigerant mixed in the water of the water circuit 210 in the load side heat exchanger 2 not only flows in the direction along the normal water flow (that is, the direction from the load side heat exchanger 2 toward the booster heater 54), but also in the pressure Due to the difference, the water flows in the direction opposite to the normal flow of water (that is, the direction from the load-side heat exchanger 2 toward the junction 230). When the pressure relief valve 70 is provided in the main circuit 220 of the water circuit 210 as in this example, the refrigerant mixed in the water can be discharged from the pressure relief valve 70 into the room together with water. Moreover, when the pressure relief valve 301 is provided in the heating circuit side piping 82a or the heating circuit side piping 82b as in this example, the refrigerant mixed in water can be discharged together with water from the pressure relief valve 301 into the room. . That is, both of the

pressure relief valves

70 and 301 function as valves that discharge the refrigerant mixed in the water in the water circuit 210 to the outside of the water circuit 210. When the refrigerant has flammability, if the refrigerant is released into the room, a combustible concentration range may be generated in the room.

However, in the present embodiment, since the shut-off device 77 is provided between the load-side heat exchanger 2 and the booster heater 54, the refrigerant flow from the load-side heat exchanger 2 toward the booster heater 54 is shut off. be able to. Therefore, it is possible to prevent the refrigerant from leaking from the pressure relief valve 70 into the room. Moreover, in this Embodiment, since the interruption | blocking apparatus 78 is provided between the load side heat exchanger 2 and the junction part 230, the flow of the refrigerant | coolant which goes to the junction part 230 from the load side heat exchanger 2 is interrupted | blocked. be able to. Therefore, the refrigerant can be prevented from leaking from the pressure relief valve 301 into the room.

FIG. 2 is a circuit diagram showing a schematic configuration of a heat pump utilizing device according to a modification of the present embodiment. As shown in FIG. 2, the present modification is different from the configuration shown in FIG. 1 in that the load side heat exchanger 2 is accommodated in the indoor unit 200. The refrigerant circuit 110 is provided across the outdoor unit 100 and the indoor unit 200. A part of the refrigerant circuit 110 is provided in the outdoor unit 100, and the other part of the refrigerant circuit 110 is provided in the indoor unit 200. The outdoor unit 100 and the indoor unit 200 are connected via two

connection pipes

111 and 112 that constitute a part of the refrigerant circuit 110. Also by this modification, the same effect as the structure shown in FIG. 1 can be acquired. Further, in this modification, the shut-off

devices

apparatus

77, 78, and the refrigerant | coolant leakage detection apparatus 98 can be connected in the indoor unit 200 via a control line, cost reduction is attained.

Next, the arrangement position of the refrigerant leak detection device 98 will be described. 3 to 6 are explanatory diagrams showing examples of arrangement positions of the refrigerant leakage detection device 98 in the heat pump utilization device according to the present embodiment. In FIG. 3, four arrangement positions A to D are shown as examples of the arrangement positions of the refrigerant leak detection device 98. In the case of the arrangement positions A and B, the refrigerant leak detection device 98 is connected to the pipe 72. That is, the refrigerant leak detection device 98 is connected to the main circuit 220 by the booster heater 54 (connection portion), similarly to the pressure relief valve 70. In such a case, before the refrigerant leaked into the water circuit 210 in the load side heat exchanger 2 is discharged from the pressure relief valve 70, the refrigerant leakage detection device 98 can reliably detect the refrigerant leakage. The same effect is obtained when the refrigerant leak detection device 98 is connected to the load side heat exchanger 2, between the load side heat exchanger 2 and the booster heater 54, or to the booster heater 54 in the main circuit 220. Can also be obtained.

The refrigerant is gasified when it leaks into the water circuit 210. For this reason, the mass velocity when the refrigerant leaks from the pressure relief valve 70 is reduced to about 1/1000 when the liquid refrigerant leaks due to the difference in the specific volume of the gas and the liquid. Therefore, the amount of the refrigerant that can be released from the pressure relief valve 70 in the time from when the refrigerant leakage is detected until the flow is interrupted by the shut-off device 77 is such that the combustible concentration region is generated indoors. Absent.

On the other hand, in the arrangement positions C and D, the refrigerant leak detection device 98 is connected between the booster heater 54 (connection part) and the three-way valve 55 in the main circuit 220. In this case, the refrigerant may be discharged from the pressure relief valve 70 before the refrigerant leakage detection device 98 detects the refrigerant leakage. However, due to the difference in specific volume between the gas and the liquid as described above, the amount of refrigerant that can be released from the pressure relief valve 70 does not reach such an amount that a combustible concentration region is generated indoors.

Also, as shown in FIG. 4, if the refrigerant leak detection device 98 is provided between the load-side heat exchanger 2 and the shut-off device 77, the shut-off device 77 is closed immediately after the refrigerant leak is detected. By doing so, the discharge amount of the refrigerant from the pressure relief valve 70 can be made substantially zero. Similarly, as shown in FIG. 5, if the refrigerant leak detection device 98 is provided between the load-side heat exchanger 2 and the shut-off device 78, the amount of refrigerant discharged from the pressure relief valve 301 is almost zero. can do. That is, it is desirable that the refrigerant leakage detection device 98 be connected between the shut-off device 77 and the shut-off device 78 in the main circuit 220 in order to make the amount of refrigerant released into the room substantially zero.

As shown in FIG. 6, when the shut-off device 78 is not a check valve but an on-off valve, the refrigerant leak detection device 98 is connected between the shut-off device 78 and the junction 230 in the main circuit 220. May be.

In all the configurations shown in FIGS. 1 to 6, the refrigerant leak detection device 98 is not a branch circuit (for example, the heating

circuit side pipes

82a and 82b and the heating device 300) constructed by a local contractor, but the main circuit 220. It is connected to the. For this reason, the manufacturer of the indoor unit 200 can attach the refrigerant leakage detection device 98 and connect the refrigerant leakage detection device 98 and the control device 201. Accordingly, human errors such as forgetting to attach the refrigerant leakage detection device 98 and forgetting to connect the refrigerant leakage detection device 98 can be avoided.

As described above, the heat pump hot water supply and heating apparatus 1000 (an example of a heat pump using device) according to the present embodiment includes the refrigerant circuit 110 that circulates the refrigerant and the water circuit 210 (heat) that circulates water (an example of a heat medium). An example of a medium circuit) and a load-side heat exchanger 2 (an example of a heat exchanger) that performs heat exchange between the refrigerant and water. The water circuit 210 has a main circuit 220 that passes through the load-side heat exchanger 2. The main circuit 220 is provided at the downstream end of the main circuit 220, and is connected to a three-way valve 55 (an example of a branch portion) to which a plurality of

branch circuits

221 and 222 branching from the main circuit 220 are connected, and And a junction unit 230 to which a plurality of

branch circuits

221 and 222 that join the main circuit 220 are connected. The main circuit 220 includes a pressure relief valve 70 (an example of a pressure protection device) that discharges water to the outside of the water circuit 210 based on the pressure in the water circuit 210, and refrigerant leakage from the refrigerant circuit 110 to the water circuit 210. And a refrigerant leakage detection device 98 for detecting The pressure relief valve 70 is connected to a booster heater 54 (an example of a connecting portion) located between the load-side heat exchanger 2 and one of the three-way valve 55 or the merging portion 230 in the main circuit 220. Between the load side heat exchanger 2 and the booster heater 54 in the main circuit 220, a shut-off device 77 (an example of a first shut-off device) capable of shutting off the flow from the load-side heat exchanger 2 to the booster heater 54 is provided. Is provided. Between the load side heat exchanger 2 and the other side of the three-way valve 55 or the junction part 230 in the main circuit 220, the interruption | blocking apparatus 78 (2nd interruption | blocking) which can interrupt | block the flow which goes to the said other from the load side heat exchanger 2 An example of an apparatus) is provided.

According to this configuration, even if the refrigerant leaks to the water circuit 210 in the load side heat exchanger 2, the flow of the refrigerant mixed in the water can be blocked by the blocking

devices

77 and 78. Therefore, it is possible to prevent the refrigerant from leaking from the pressure relief valve 70 into the room. Furthermore, it is possible to prevent the refrigerant from leaking into the room from the pressure relief valve 301 that may be provided in a circuit (for example, the heating

circuit side pipes

82a and 82b) ahead of the branch portion.

In the heat pump hot water supply and heating device 1000 according to the present embodiment, the shut-off

devices

77 and 78 are on-off valves that are closed when refrigerant leakage to the water circuit 210 is detected. According to this configuration, when the refrigerant leaks into the water circuit 210, the flow of the refrigerant mixed in the water can be blocked more reliably.

In heat pump hot water supply and heating apparatus 1000 according to the present embodiment, refrigerant leak detection apparatus 98 is connected to junction section 230, junction section 230 and booster heater 54, or to booster heater 54 in main circuit 220. . According to this configuration, the leakage of the refrigerant can be reliably detected before the refrigerant that has leaked into the water circuit 210 is released into the room.

In the heat pump hot water supply and heating apparatus 1000 according to the present embodiment, the shut-off device 78 provided between the load-side heat exchanger 2 and the merging portion 230 among the shut-off

devices

77 and 78 is a check valve. The refrigerant leak detection device 98 is connected to the booster heater 54 or between the check valve and the booster heater 54 in the main circuit 220. According to this configuration, the leakage of the refrigerant can be reliably detected before the refrigerant that has leaked into the water circuit 210 is released into the room.

In the heat pump hot water supply and heating device 1000 according to the present embodiment, the refrigerant leakage detection device 98 is connected between the cutoff device 77 and the cutoff device 78 in the main circuit 220. According to this configuration, the amount of refrigerant released from the pressure relief valve can be made substantially zero.

In the heat pump hot water supply and heating apparatus 1000 according to the present embodiment, the refrigerant leakage detection device 98 detects refrigerant leakage to the water circuit 210 based on the pressure in the water circuit 210. According to this configuration, leakage of the refrigerant can be reliably detected.

Heat pump hot water supply and heating apparatus 1000 according to the present embodiment includes an outdoor unit 100 that houses refrigerant circuit 110, a part of water circuit 210, and load-side heat exchanger 2, and an indoor unit 200 that houses the other part of water circuit 210. And further. One of the outdoor unit 100 or the indoor unit 200 accommodates shut-off

devices

77 and 78 and a refrigerant leak detection device 98. According to this configuration, since the control device 101 or the control device 201 can be connected to each of the shut-off

devices

77 and 78 and the refrigerant leakage detection device 98 in the outdoor unit 100 or the indoor unit 200, the cost can be reduced. Become.

The heat pump hot water supply and heating apparatus 1000 according to the present embodiment includes an outdoor unit 100 that houses a part of the refrigerant circuit 110, and an indoor unit 200 that houses the other part of the refrigerant circuit 110, the water circuit 210, and the load-side heat exchanger 2. And further. The indoor unit 200 houses shut-off

devices

77 and 78 and a refrigerant leak detection device 98. According to this configuration, since the control device 201, the shut-off

devices

77 and 78, and the refrigerant leakage detection device 98 can be connected within the indoor unit 200, the cost can be reduced.

In the heat pump hot water supply and heating apparatus 1000 according to the present embodiment, the refrigerant may be a combustible refrigerant or a toxic refrigerant.

Embodiment 2. FIG.
A heat pump utilizing device according to Embodiment 2 of the present invention will be described. FIG. 7 is a circuit diagram showing a schematic configuration of the heat pump utilizing device according to the present embodiment. FIG. 7 mainly shows the configuration of the indoor unit 200. In addition, about the component which has the function and effect | action same as Embodiment 1, the same code | symbol is attached | subjected and the description is abbreviate | omitted. As shown in FIG. 7, in the present embodiment, a boiling circuit 240 that heats the water stored in the hot water storage tank 51 is provided outside the hot water storage tank 51. The boiling circuit 240 has a water flow path that connects the lower part and the upper part of the hot water storage tank 51. The boiling circuit 240 is provided with a boiling pump 241 and a boiling heat exchanger 242 that performs heat exchange between water flowing in the boiling circuit 240 and water flowing in the branch circuit 221. When the boiling pump 241 operates, the water below the hot water storage tank 51 flows into the boiling circuit 240. The water flowing into the boiling circuit 240 is heated by heat exchange in the boiling heat exchanger 242 and returns to the upper part of the hot water storage tank 51. Also in the present embodiment, the same effect as in the first embodiment can be obtained.

The present invention is not limited to the above embodiment, and various modifications can be made.
For example, in the above embodiment, a plate-type heat exchanger has been exemplified as the load-side heat exchanger 2, but the load-side heat exchanger 2 can perform heat exchange between the refrigerant and the heat medium, Other than the plate-type heat exchanger such as a double-pipe heat exchanger may be used.

Moreover, in the said embodiment, although the heat pump hot water supply and heating apparatus 1000 was mentioned as an example as a heat pump utilization apparatus, this invention is applicable also to other heat pump utilization apparatuses, such as a chiller.

In the above embodiment, the indoor unit 200 provided with the hot water storage tank 51 is taken as an example, but the hot water storage tank may be provided separately from the indoor unit 200.

The above embodiments and modifications can be implemented in combination with each other.

1. Heat source side heat exchanger, 2. Load side heat exchanger, 3. Compressor, 4. Refrigerant flow path switching device, 5. Medium pressure receiver, 6. First decompression device, 7. Second decompression device, 11. Intake pipe, 51. Hot water storage tank. 52 expansion tank, 53 pump, 54 booster heater, 55 three-way valve, 56 strainer, 57 flow switch, 60 submerged heater, 61 coil, 62, 63 drain, 70 pressure relief valve, 72 piping, 72a branch, 75 piping, 77, 78 Shut-off device, 81a, 81b Sanitary circuit side piping, 82a, 82b Heating circuit side piping, 98 Refrigerant leak detection device, 100 Outdoor unit, 101 Control device, 102 Control line, 110 Refrigerant circuit, 111, 112 Connection piping, 200 indoor units, 201 control device, 202 operation unit, 203 display unit, 210 Water circuit, 211, 212 connection pipe, 220 main circuit, 221, 222 branch circuit, 222a forward pipe, 222b return pipe, 230 junction, 240 boiling circuit, 241 boiling pump, 242 boiling heat exchanger, 300 heating Equipment, 301 pressure relief valve, 1000 heat pump hot water heater.

Claims

A refrigerant circuit for circulating the refrigerant;
A heat medium circuit for circulating the heat medium;
A heat exchanger that performs heat exchange between the refrigerant and the heat medium,
The heat medium circuit has a main circuit via the heat exchanger,
The main circuit is:
A branch portion provided at a downstream end of the main circuit and connected to a plurality of branch circuits branching from the main circuit;
A merging portion provided at an upstream end of the main circuit and connected to the plurality of branch circuits merging with the main circuit;
A pressure protection device and a refrigerant leakage detection device are connected to the main circuit,
The pressure protection device is connected to a connection part located between the heat exchanger and one of the branch part or the junction part in the main circuit,
Between the heat exchanger and the connection part in the main circuit, a first shut-off device capable of interrupting the flow from the heat exchanger toward the connection part is provided,
Use of heat pump in which a second shutoff device capable of shutting off the flow from the heat exchanger toward the other side is provided between the heat exchanger and the other of the branching section or the joining section in the main circuit machine.
The heat pump utilizing device according to claim 1, wherein the first shut-off device and the second shut-off device are on-off valves that are closed when leakage of the refrigerant to the heat medium circuit is detected.
3. The heat pump utilization device according to claim 1, wherein the refrigerant leakage detection device is connected to the junction, the junction and the connection, or the connection in the main circuit. .
Of the first shut-off device and the second shut-off device, the shut-off device provided between the heat exchanger and the junction is a check valve,
The said refrigerant | coolant leakage detection apparatus is a heat pump utilization apparatus of Claim 1 connected between the said non-return valve and the said connection part among the said main circuits, or the said connection part.
The heat pump utilization device according to any one of claims 1 to 4, wherein the refrigerant leakage detection device is connected between the first shut-off device and the second shut-off device in the main circuit. .
6. The heat pump utilization device according to claim 1, wherein the refrigerant leakage detection device detects leakage of the refrigerant to the heat medium circuit based on a pressure in the heat medium circuit.
An outdoor unit that houses the refrigerant circuit, a part of the heat medium circuit, and the heat exchanger;
An indoor unit that accommodates the other part of the heat medium circuit,
The heat pump utilization according to any one of claims 1 to 6, wherein one of the outdoor unit or the indoor unit accommodates the first shut-off device, the second shut-off device, and the refrigerant leak detection device. machine.
An outdoor unit that houses a part of the refrigerant circuit;
An indoor unit that houses the other part of the refrigerant circuit, the heat medium circuit, and the heat exchanger;
The heat pump using device according to any one of claims 1 to 6, wherein the indoor unit houses the first shut-off device, the second shut-off device, and the refrigerant leak detection device.
The heat pump using device according to any one of claims 1 to 8, wherein the refrigerant is a combustible refrigerant or a toxic refrigerant.