JPWO2013111180A1 - Refrigerant charging method for air conditioner, air conditioner - Google Patents

Abstract

The difference between the saturated gas temperature on the inlet side of the first refrigerant in the heating heat exchanger 15c and the saturated liquid temperature on the outlet side is defined as a first temperature difference, and the outlet side of the second refrigerant in the heating heat exchanger 15c is determined. When the difference between the saturated gas temperature and the inlet side temperature is the second temperature difference, the second refrigeration cycle includes the second refrigeration cycle so that a plurality of single refrigerants constituting the second refrigerant have a predetermined mixing ratio. Two refrigerants are charged, and the difference between the first temperature difference and the second temperature difference is kept below a predetermined value.

Description

  The present invention relates to a refrigerant filling method of an air conditioner applied to, for example, a building multi-air conditioner, and the like, and an air conditioner filled with a refrigerant by the method.

  Conventionally, an intermediate heat exchanger having a first refrigeration cycle on a high-source side and a second refrigeration cycle on a low-source side and for exchanging heat in a counterflow with the refrigerant circulating through these refrigeration cycles is mounted. In addition, there is a binary air conditioner (see, for example, Patent Document 1). The technology described in Patent Document 1 employs non-azeotropic refrigerant mixtures with different temperature gradients as refrigerant circulating in the first and second refrigeration cycles.

  In addition, in consideration of the fact that the circulation composition of the refrigerant changes depending on the amount of liquid refrigerant stored in the accumulator, it is possible to control the condensation temperature and the evaporation temperature and to improve the heat exchange efficiency. An apparatus has also been proposed (see, for example, Patent Document 2).

  Furthermore, a building multi-air conditioner has been proposed that has a first refrigeration cycle and a second refrigeration cycle, and is capable of generating hot water by exchanging heat between the refrigerant circulating through them (for example, And Patent Document 3).

JP-A-7-269964 (see, for example, page 6 of the specification and FIG. 3) Japanese Patent Laid-Open No. 11-182951 (see, for example, pages 5 and 6 of the specification and FIG. 1) WO2009 / 098751 (see, for example, page 5 of the specification and FIG. 1)

  The technology described in Patent Document 1 can improve the heat exchange efficiency by making the refrigerant supplied to the intermediate heat exchanger counterflow, but the temperature gradient of the non-azeotropic refrigerant mixture in the ph diagram From this point of view, the heat exchange efficiency was not improved. That is, the technique described in Patent Document 1 is caused by the fact that the temperature gradient between the non-azeotropic refrigerant mixture flowing in the first refrigeration cycle and the non-azeotropic refrigerant mixture flowing in the second refrigeration cycle is greatly different. There was a problem that the heat exchange efficiency would be reduced.

  The technology described in Patent Document 2 can improve the heat exchange efficiency by considering that the circulation composition of the refrigerant changes, but from the viewpoint of the temperature gradient of the non-azeotropic refrigerant mixture in the ph diagram It did not improve the heat exchange efficiency. That is, the technique described in Patent Document 2 does not consider that the heat exchange efficiency is reduced if the temperature gradients of the non-azeotropic refrigerants in different refrigeration cycles are different. When the refrigerant is applied, there is a problem that the heat exchange efficiency is reduced.

  In the technique described in Patent Document 3, since the refrigerant circulating in the first refrigeration cycle and the second refrigeration cycle is not a non-azeotropic refrigerant mixture, heat exchange is performed by the temperature gradient of the non-azeotropic refrigerant mixture in the ph diagram. The efficiency did not decrease. That is, since the technique described in Patent Document 3 does not improve the heat exchange efficiency from the viewpoint of the temperature gradient of the non-azeotropic refrigerant mixture in the ph diagram, when the non-azeotropic refrigerant mixture is applied as the refrigerant, There was a problem that efficiency was reduced.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a refrigerant charging method for an air-conditioning apparatus that can improve heat exchange efficiency.

  The refrigerant filling method of the air conditioner according to the present invention includes the first compressor, the heat source side heat exchanger, the first expansion device, the first heat exchanger related to heat medium, and the first flow path of the heating heat exchanger. A first refrigerating pipe is connected to form a first refrigeration cycle, and the second compressor, the second flow path of the heating heat exchanger, the second expansion device, and the second heat exchanger related to heat medium are secondly connected. The refrigerant pipe is connected to form a second refrigeration cycle, and the first refrigerant that fills the first refrigeration cycle and the second refrigerant that fills the second refrigeration cycle are saturated gas temperature and saturated liquid temperature at the same pressure. In the refrigerant charging method of the air conditioner in which the first refrigerant and the second refrigerant are heat-exchanged by the heating heat exchanger, the heating heat exchanger is the heating heat exchanger. The first refrigerant supplied to the first flow path and the second refrigerant supplied to the second flow path are opposed to each other. A difference between a saturated gas temperature on the inlet side and a saturated liquid temperature on the outlet side of the first refrigerant in the heating heat exchanger connected to the first refrigerant pipe and the second refrigerant pipe is defined as a first temperature difference. When the difference between the saturated gas temperature on the outlet side of the second refrigerant in the heat exchanger and the temperature on the inlet side is the second temperature difference, the plurality of single refrigerants constituting the second refrigerant are at a predetermined mixing ratio. In this way, the second refrigerant is filled in the second refrigeration cycle, and the difference between the first temperature difference and the second temperature difference is kept below a predetermined value.

According to the refrigerant filling method of the air conditioner of the present invention, the second refrigerant is charged into the second refrigeration cycle so that the plurality of single refrigerants constituting the second refrigerant have a predetermined mixing ratio, and the first refrigerant is charged. By keeping the difference between the temperature difference and the second temperature difference below a predetermined value, the heat exchange efficiency between the first refrigerant and the second refrigerant flowing into the heat exchanger for heating can be improved.
Moreover, according to the refrigerant | coolant filling method of the air conditioning apparatus of this invention, energy saving can be achieved by the part which can improve heat exchange efficiency.

It is the schematic which shows the example of installation of the air conditioning apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the circuit structural example of the air conditioning apparatus which concerns on Embodiment 1 of this invention. It is a figure explaining the flow of the refrigerant | coolant and heat medium at the time of the cooling only operation | movement of the air conditioning apparatus shown in FIG. It is a figure explaining the flow of the refrigerant | coolant and heat medium at the time of the all heating operation of the air conditioning apparatus shown in FIG. It is a figure explaining the flow of the refrigerant | coolant and heat medium at the time of the cooling main operation | movement of the air conditioning apparatus shown in FIG. It is a figure explaining the flow of the refrigerant | coolant and heat medium at the time of heating main operation | movement of the air conditioning apparatus shown in FIG. It is explanatory drawing of the ph diagram of a predetermined non-azeotropic refrigerant. It is a case where a non-azeotropic refrigerant is adopted as the first heat source side refrigerant and a single refrigerant is adopted as the second heat source side refrigerant, and is an explanatory diagram of both refrigerant temperatures in the heat exchanger for heating. It is a case where a non-azeotropic refrigerant is adopted as the first heat source side refrigerant and the second heat source side refrigerant, and is an explanatory diagram of both refrigerant temperatures in the heat exchanger for heating. It is explanatory drawing of the temperature difference of the saturated gas and saturated liquid in the same pressure of the non-azeotropic refrigerant mixture supplied to a heat exchanger between heat media. It is a circuit structural example of the air conditioning apparatus which concerns on Embodiment 2 of this invention.

Embodiment 1 FIG.
1 is a schematic diagram illustrating an installation example of an air-conditioning apparatus according to Embodiment 1. FIG. Based on FIG. 1, the installation example of an air conditioning apparatus is demonstrated. In addition, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one.

In FIG. 1, the air conditioner according to the present embodiment includes one outdoor unit 1 that is a heat source unit, a plurality of indoor units 2, and heat that is interposed between the outdoor unit 1 and the indoor unit 2. It has a medium converter 3 and a hot water supply device 14.
The outdoor unit 1 and the heat medium relay unit 3 are connected by a refrigerant pipe 4 that conducts the first heat source side refrigerant. The heat medium relay unit 3 and the indoor unit 2 are connected by a pipe (heat medium pipe) 5 that conducts the first heat medium. The hot water supply device 14 and the heat medium relay unit 3 are connected by a refrigerant pipe 4 that conducts the first heat source side refrigerant.
The hot water supply device 14 is connected to a hot water storage tank 24 which will be described later, and the heat generated by the outdoor unit 1 is used to heat water stored in the hot water storage tank 24.

The outdoor unit 1 is normally disposed in an outdoor space 6 that is a space outside a building 9 such as a building (for example, a rooftop), and supplies cold or hot heat to the indoor unit 2 via the heat medium converter 3. It is. The indoor unit 2 is disposed at a position where cooling air or heating air can be supplied to the indoor space 7 which is a space (for example, a living room) inside the building 9, and the cooling air is supplied to the indoor space 7 as the air-conditioning target space. Alternatively, heating air is supplied.
The heat medium relay unit 3 is configured as a separate housing from the outdoor unit 1 and the indoor unit 2 and is configured to be installed at a position different from the outdoor space 6 and the indoor space 7. Is connected to the refrigerant pipe 4 and the heat medium pipe 5, respectively, and transmits cold heat or hot heat supplied from the outdoor unit 1 to the indoor unit 2.
The hot water supply device 14 supplies hot water to a load side such as hot water supply. In FIG. 1, the hot water supply device 14 is illustrated as being installed in the indoor space 7, but is not limited thereto, and is installed, for example, at any position inside the building 9. Good.

As shown in FIG. 1, in the air-conditioning apparatus according to Embodiment 1, an outdoor unit 1 and a heat medium converter 3 are connected via a refrigerant pipe 4, and the heat medium converter 3 and a hot water supply device. 14 is connected through the refrigerant pipe 4. The heat medium converter 3 and each indoor unit 2 are connected via a heat medium pipe 5.
As described above, the air conditioner according to the present embodiment is configured by connecting each unit (the outdoor unit 1, the indoor unit 2, the hot water supply device 14, and the heat medium converter 3) by the refrigerant pipe 4 and the heat medium pipe 5. Construction is easy.

  In FIG. 1, the heat medium converter 3 is installed in a space such as the back of the ceiling (hereinafter simply referred to as a space 8) that is inside the building 9 but is different from the indoor space 7. The state is shown as an example. The heat medium relay 3 can also be installed in a common space where there is an elevator or the like. Moreover, in FIG. 1, although the case where the indoor unit 2 is a ceiling cassette type | mold is shown as an example, it is not limited to this, It is directly or directly in the indoor space 7, such as a ceiling embedded type and a ceiling suspended type. Any type of air may be used as long as heating air or cooling air can be blown out by a duct or the like.

  In FIG. 1, the case where the outdoor unit 1 is installed in the outdoor space 6 is shown as an example, but the present invention is not limited to this. For example, the outdoor unit 1 may be installed in an enclosed space such as a machine room with a ventilation opening. If the waste heat can be exhausted outside the building 9 by an exhaust duct, the outdoor unit 1 may be installed inside the building 9. It may be installed, or may be installed inside the building 9 when the water-cooled outdoor unit 1 is used. Even if the outdoor unit 1 is installed in such a place, no particular problem occurs.

  Further, the heat medium relay unit 3 can be installed in the vicinity of the outdoor unit 1. However, it should be noted that if the distance from the heat medium relay unit 3 to the indoor unit 2 is too long, the power for transporting the first heat medium becomes considerably large, and thus the energy saving effect is diminished. Furthermore, the number of connected outdoor units 1, indoor units 2, and heat medium converters 3 is not limited to the number shown in FIG. 1, but in building 9 where the air conditioner according to the present embodiment is installed. The number of units may be determined accordingly.

FIG. 2 is a diagram illustrating a circuit configuration example of the air-conditioning apparatus (hereinafter referred to as the air-conditioning apparatus 100) according to the embodiment of the present invention. Based on FIG. 2, the detailed structure of the air conditioning apparatus 100 is demonstrated.
As shown in FIG. 2, the outdoor unit 1 and the heat medium converter 3 are connected to each other by inter-heat medium heat exchangers 15 a and 15 b through a refrigerant pipe 4 to constitute a first refrigeration cycle. And the indoor unit 2 are connected to the heat exchangers 15a, 15b and the like by the heat medium pipe 5 to constitute a first heat medium cycle.
The hot water supply device 14 is connected to a heating heat exchanger 15c or the like by a refrigerant pipe 4c to form a second refrigeration cycle. It is connected by a pipe 5a to constitute a second heat medium cycle.

[Outdoor unit 1]
In the outdoor unit 1, a compressor 10 a, a first refrigerant flow switching device 11 such as a four-way valve, a heat source side heat exchanger 12, and an accumulator 19 are connected and mounted via a refrigerant pipe 4. Yes. The outdoor unit 1 is also provided with a first connection pipe 4a, a second connection pipe 4b, a check valve 13a, a check valve 13b, a check valve 13c, and a check valve 13d. Regardless of the operation that the indoor unit 2 requires, the heat medium is provided by providing the first connection pipe 4a, the second connection pipe 4b, the check valve 13a, the check valve 13b, the check valve 13c, and the check valve 13d. The flow of the first heat source side refrigerant flowing into the converter 3 can be in a certain direction.

The compressor 10a sucks the first heat source side refrigerant and compresses the first heat source side refrigerant to a high temperature / high pressure state. For example, the compressor 10a may be composed of an inverter compressor capable of capacity control. The compressor 10 a has a discharge side connected to the first refrigerant flow switching device 11 and a suction side connected to the accumulator 19. The compressor 10a corresponds to the first compressor.
The first refrigerant flow switching device 11 is configured so that the flow of the first heat source side refrigerant during the heating operation (in the heating only operation mode and the heating main operation mode) and the cooling operation (in the all cooling operation mode and the cooling main operation mode). ) To switch the flow of the first heat source side refrigerant. In FIG. 2, the first refrigerant flow switching device 11 connects the discharge side of the compressor 10 and the first connection pipe 4 a and connects the heat source side heat exchanger 12 and the accumulator 19. The state is illustrated.

The heat source side heat exchanger 12 functions as an evaporator during heating operation, functions as a condenser (or radiator) during cooling operation, and generates heat between air and refrigerant supplied from a blower such as a fan (not shown). Exchange is performed, and the refrigerant is evaporated or condensed and liquefied. One of the heat source side heat exchangers 12 is connected to the first refrigerant flow switching device 11, and the other is connected to the refrigerant pipe 4 provided with the check valve 13a.
The accumulator 19 stores excess refrigerant. One of the accumulators 19 is connected to the first refrigerant flow switching device 11, and the other is connected to the suction side of the compressor 10a.

  The check valve 13a is provided in the refrigerant pipe 4 between the heat source side heat exchanger 12 and the heat medium converter 3, and the check valve 13a is used only in a predetermined direction (direction from the outdoor unit 1 to the heat medium converter 3). It allows flow. The check valve 13b is provided in the first connection pipe 4a, and causes the refrigerant discharged from the compressor 10a during the heating operation to flow to the heat medium relay unit 3. The check valve 13c is provided in the second connection pipe 4b, and causes the refrigerant returned from the heat medium relay unit 3 to flow to the suction side of the compressor 10 during the heating operation. The check valve 13d is provided in the refrigerant pipe 4 between the heat medium converter 3 and the first refrigerant flow switching device 11, and only in a predetermined direction (direction from the heat medium converter 3 to the outdoor unit 1). The refrigerant flow is allowed.

In the outdoor unit 1, the first connection pipe 4a is a refrigerant pipe 4 between the first refrigerant flow switching device 11 and the check valve 13d, and a refrigerant between the check valve 13a and the heat medium relay unit 3. The pipe 4 is connected.
In the outdoor unit 1, the second connection pipe 4b includes a refrigerant pipe 4 between the check valve 13d and the heat medium relay unit 3, and a refrigerant pipe 4 between the heat source side heat exchanger 12 and the check valve 13a. Are connected to each other.
In addition, although the air conditioning apparatus 100 shown in FIG. 2 is provided with the 1st connection piping 4a, the 2nd connection piping 4b, and the check valves 13a-13d, it is not limited to it. That is, the first connection pipe 4a, the second connection pipe 4b, and the check valves 13a to 13d are not necessarily provided in the air conditioner 100.

[Indoor unit 2]
Each indoor unit 2 is equipped with a use side heat exchanger 26. The use side heat exchanger 26 is connected to the heat medium flow control device 25 and the second heat medium flow switching device 23 of the heat medium converter 3 by the heat medium pipe 5. The use-side heat exchanger 26 exchanges heat between air supplied from a blower such as a fan (not shown) and the first heat medium, and supplies heating air or cooling air to the indoor space 7. Is generated.

  FIG. 2 shows an example in which four indoor units 2 are connected to the heat medium relay unit 3, and are illustrated as an indoor unit 2a, an indoor unit 2b, an indoor unit 2c, and an indoor unit 2d from the bottom of the page. Show. Further, in accordance with the indoor unit 2a to the indoor unit 2d, the use side heat exchanger 26 also uses the use side heat exchanger 26a, the use side heat exchanger 26b, the use side heat exchanger 26c, and the use side heat exchange from the lower side of the drawing. It is shown as a container 26d. As in FIG. 1, the number of indoor units 2 connected is not limited to four as shown in FIG.

[Heat medium converter 3]
The heat medium relay 3 includes two heat medium heat exchangers 15, two expansion devices 16, two opening / closing devices 17, two second refrigerant flow switching devices 18, and two pumps 21. Four first heat medium flow switching devices 22, four second heat medium flow switching devices 23, and four heat medium flow control devices 25 are mounted.
In addition, the heat medium relay 3 is provided with various detection devices (two first temperature sensors 31, four second temperature sensors 34, four third temperature sensors 35, and a pressure sensor 36).

  The two heat exchangers between heat mediums 15 (heat medium heat exchanger 15a, heat medium heat exchanger 15b) function as a condenser (heat radiator) or an evaporator, and the first heat source side refrigerant and the first heat Heat exchange is performed with the medium, and the cold or warm heat generated in the outdoor unit 1 and stored in the first heat source side refrigerant is transmitted to the first heat medium. The heat exchanger related to heat medium 15a is provided between the expansion device 16a and the second refrigerant flow switching device 18a in the refrigerant circuit A, and serves to cool the first heat medium in the cooling / heating mixed operation mode. Is. Further, the heat exchanger related to heat medium 15b is provided between the expansion device 16b and the second refrigerant flow switching device 18b in the refrigerant circuit A, and heats the first heat medium in the cooling / heating mixed operation mode. It is for use. The heat exchangers related to heat medium 15a and 15b correspond to the first heat exchanger related to heat medium.

  The two expansion devices 16 (the expansion device 16a and the expansion device 16b) have functions as pressure reducing valves and expansion valves, and expand the first heat source side refrigerant by reducing the pressure. The expansion device 16a is provided on the upstream side of the heat exchanger related to heat medium 15a in the flow of the first heat source side refrigerant during the cooling operation. The expansion device 16b is provided on the upstream side of the heat exchanger related to heat medium 15b in the flow of the first heat source side refrigerant during the cooling operation. The two expansion devices 16 may be configured by a device whose opening degree can be variably controlled, for example, an electronic expansion valve. The diaphragm devices 16a and 16b correspond to the first diaphragm device.

  The two opening / closing devices 17 (the opening / closing device 17a and the opening / closing device 17b) are configured by a two-way valve or the like, and open / close the refrigerant pipe 4. The opening / closing device 17a is provided in the refrigerant pipe 4 on the inlet side of the first heat source side refrigerant. The opening / closing device 17b is provided in a pipe connecting the refrigerant pipe 4 on the inlet side and the outlet side of the first heat source side refrigerant. The two second refrigerant flow switching devices 18 (second refrigerant flow switching device 18a and second refrigerant flow switching device 18b) are configured by four-way valves or the like, and the flow of the first heat source side refrigerant according to the operation mode. Is to switch. The second refrigerant flow switching device 18a is provided on the downstream side of the heat exchanger related to heat medium 15a in the flow of the first heat source side refrigerant during the cooling operation. The second refrigerant flow switching device 18b is provided on the downstream side of the heat exchanger related to heat medium 15b in the flow of the first heat source side refrigerant during the cooling operation.

  The two pumps 21 (pump 21 a and pump 21 b) circulate the first heat medium that conducts the heat medium pipe 5. The pump 21 a is provided in the heat medium pipe 5 between the heat exchanger related to heat medium 15 a and the second heat medium flow switching device 23. The pump 21 b is provided in the heat medium pipe 5 between the heat exchanger related to heat medium 15 b and the second heat medium flow switching device 23. The two pumps 21 may be constituted by, for example, pumps capable of capacity control.

The four first heat medium flow switching devices 22 (the first heat medium flow switching device 22a to the first heat medium flow switching device 22d) are configured by a three-way valve or the like. Is to switch. The first heat medium flow switching device 22 is provided in a number (here, four) according to the number of indoor units 2 installed.
The first heat medium flow switching device 22 is provided on the outlet side of the heat medium flow path of the use side heat exchanger 26. Specifically, the first heat medium flow switching device 22 is connected to the heat exchanger related to heat medium 15 a, the heat exchanger related to heat medium 15 b, and the heat medium flow control device 25.

The four second heat medium flow switching devices 23 (second heat medium flow switching device 23a to second heat medium flow switching device 23d) are configured by a three-way valve or the like, and the flow path of the first heat medium. Is to switch. The number of the second heat medium flow switching devices 23 is set according to the number of installed indoor units 2 (here, four).
The second heat medium flow switching device 23 is provided on the inlet side of the flow path of the first heat medium of the use side heat exchanger 26. Specifically, the second heat medium flow switching device 23 is connected to the heat exchanger related to heat medium 15 a, the heat exchanger related to heat medium 15 b, and the use side heat exchanger 26.

The four heat medium flow control devices 25 (heat medium flow control device 25a to heat medium flow control device 25d) are configured by a two-way valve or the like capable of controlling the opening area, and control the flow rate flowing through the heat medium pipe 5. Is. The number of the heat medium flow control devices 25 is set according to the number of indoor units 2 installed (four in this case).
The heat medium flow control device 25 is provided on the outlet side of the heat medium flow path of the use side heat exchanger 26. Specifically, one of the heat medium flow control devices 25 is connected to the use side heat exchanger 26 and the other is connected to the first heat medium flow switching device 22. The heat medium flow control device 25 may be provided on the inlet side of the flow path of the first heat medium of the use side heat exchanger 26.

The two first temperature sensors 31 (the first temperature sensor 31a and the first temperature sensor 31b) are the first heat medium that has flowed out of the heat exchanger related to heat medium 15, that is, the first heat medium at the outlet of the heat exchanger related to heat medium 15. The temperature of the heat medium is detected, and for example, a thermistor may be used.
The first temperature sensor 31a is provided in the heat medium pipe 5 on the inlet side of the pump 21a. The first temperature sensor 31b is provided in the heat medium pipe 5 on the inlet side of the pump 21b.

The four second temperature sensors 34 (second temperature sensor 34a to second temperature sensor 34d) are provided between the first heat medium flow switching device 22 and the heat medium flow control device 25, and use side heat exchangers. 26, the temperature of the first heat medium flowing out from the heater 26 is detected, and it may be constituted by a thermistor or the like.
The number of the second temperature sensors 34 (four here) according to the number of indoor units 2 installed is provided. The second temperature sensor 34 may be provided in a flow path between the heat medium flow control device 25 and the use side heat exchanger 26. Further, the heat medium flow control device 25 may be provided on the inlet side of the flow path of the first heat medium of the use side heat exchanger 26.

The four third temperature sensors 35 (third temperature sensor 35a to third temperature sensor 35d) are provided on the inlet side or the outlet side of the first heat source side refrigerant of the heat exchanger related to heat medium 15 to perform heat exchange between heat media. The temperature of the 1st heat source side refrigerant | coolant which flows in into the container 15 or the temperature of the 1st heat source side refrigerant | coolant which flowed out from the heat exchanger 15 between heat media is detected, and it is good to comprise with a thermistor etc.
The third temperature sensor 35a is provided between the heat exchanger related to heat medium 15a and the second refrigerant flow switching device 18a. The third temperature sensor 35b is provided between the heat exchanger related to heat medium 15a and the expansion device 16a. The third temperature sensor 35c is provided between the heat exchanger related to heat medium 15b and the second refrigerant flow switching device 18b. The third temperature sensor 35d is provided between the heat exchanger related to heat medium 15b and the expansion device 16b.

  Similar to the installation position of the third temperature sensor 35d, the pressure sensor 36 is provided between the heat exchanger related to heat medium 15b and the expansion device 16b, and between the heat exchanger related to heat medium 15b and the expansion device 16b. The pressure of the flowing first heat source side refrigerant is detected.

  The heat medium pipe 5 that conducts the heat medium is composed of one connected to the heat exchanger related to heat medium 15a and one connected to the heat exchanger related to heat medium 15b. The heat medium pipe 5 is branched (here, four branches each) according to the number of indoor units 2 connected to the heat medium converter 3. The heat medium pipe 5 is connected by a first heat medium flow switching device 22 and a second heat medium flow switching device 23. By controlling the first heat medium flow switching device 22 and the second heat medium flow switching device 23, the heat medium from the heat exchanger related to heat medium 15a flows into the use-side heat exchanger 26, or the heat medium Whether the heat medium from the intermediate heat exchanger 15b flows into the use side heat exchanger 26 is determined.

[Hot water supply device 14, pump 21c, hot water storage tank 24]
The hot water supply device 14 transmits the temperature of the first heat source side refrigerant to the second heat source side refrigerant, and further transmits the temperature of the second heat source side refrigerant to the second heat medium.
The hot water supply device 14 includes a compressor 10b that compresses the second heat source side refrigerant, a heat exchanger related to heat medium 15d that functions as a condenser, and a second heat source side refrigerant that constitute the second refrigeration cycle. An expansion device 16d for reducing the pressure and a heating heat exchanger 15c functioning as an evaporator are mounted.
In addition, the hot water supply device 14 is equipped with a throttle device 16c that forms part of the first refrigeration cycle and depressurizes the first heat source side refrigerant.
In addition, the hot water supply device 14 is connected to a pump 21c for conveying the second heat medium and a hot water storage tank 24 capable of storing the second heat medium, as constituting the second heat medium cycle. ing.

The hot water supply device 14 further includes a second pressure sensor 37 that detects the pressure of the second heat source side refrigerant, a third pressure sensor 39 that detects the pressure of the first heat source side refrigerant, and a temperature of the second heat source side refrigerant. The fourth temperature sensor 38, the fifth temperature sensor 40 for detecting the temperature of the first heat source side refrigerant, and the sixth temperature sensor 41 for detecting the temperature of the second heat medium are provided.
In addition, as shown in FIG. 2, the air-conditioning harmony device 100 is not limited to the structure provided with one hot-water supply apparatus 14, and multiple units may be provided. In addition, when the air conditioning apparatus 100 is provided with two or more hot water supply apparatuses 14, it is good for the hot water supply apparatus 14 to be connected in parallel with the heat medium converter 3 via the refrigerant | coolant piping 4. FIG.

  The compressor 10b sucks the second heat source side refrigerant and compresses the second heat source side refrigerant to a high temperature and high pressure state, and may be configured by an inverter compressor whose capacity can be controlled, for example. The compressor 10b has a discharge side connected to the heat exchanger related to heat medium 15d and a suction side connected to the heat exchanger 15c for heating. The compressor 10b corresponds to a second compressor.

The heat exchanger for heating 15c functions as an evaporator, and heat is exchanged between the first heat source side refrigerant and the second heat source side refrigerant, thereby being generated in the outdoor unit 1 and stored in the first heat source side refrigerant. Heat is transmitted to the second heat source side refrigerant. One side of the second heat source side of the heating heat exchanger 15c is connected to the suction side of the compressor 10b, and the other side is connected to the expansion device 16d.
In the heating heat exchanger 15c, the flow direction of the first heat source side refrigerant and the flow direction of the second heat source side refrigerant in the heating heat exchanger 15c are opposed to each other regardless of the operation mode. Are connected to the refrigerant pipe 4 and the refrigerant pipe 4c. Thereby, the heat exchange efficiency in the heat exchanger 15c for heating is improved.

The expansion device 16d has a function as a pressure reducing valve or an expansion valve, and expands the second heat source side refrigerant by reducing the pressure. One of the expansion devices 16d is connected to the intermediate heat exchanger 15d, and the other is connected to the heating heat exchanger 15c. The expansion device 16d may be capable of adjusting the opening by providing a stepping motor, for example. The diaphragm device 16c corresponds to the first diaphragm device, similarly to the diaphragm devices 16a and 16b.
The heat exchanger related to heat medium 15d functions as a condenser (heat radiator) and performs heat exchange between the second heat source side refrigerant and the second heat medium, thereby generating the second heat source side refrigerant generated in the hot water supply device 14. The heat stored in is transferred to the second heat medium. One side of the second heat source side of the heat exchanger related to heat medium 15d is connected to the discharge side of the compressor 10b, and the other side is connected to the expansion device 16d. Note that the heat exchanger related to heat medium 15d corresponds to a second heat exchanger related to heat medium.

  The expansion device 16c functions as a pressure reducing valve or an expansion valve, and expands the first heat source side refrigerant by reducing the pressure. The expansion device 16c is provided on the downstream side of the heating heat exchanger 15c in the flow of the first heat source side refrigerant during the heating only operation, the heating main operation, and the cooling main operation. The expansion device 16c may be capable of adjusting the opening by providing a stepping motor, for example. The diaphragm device 16c corresponds to the first diaphragm device.

  The pump 21c circulates the second heat medium that is conducted through the heat medium pipe 5a. The pump 21 c is provided in the heat medium pipe 5 a between the heat exchanger related to heat medium 15 d and the hot water storage tank 24. The pump 21c may be constituted by a pump whose capacity can be controlled, for example.

  The hot water storage tank 24 stores the second heat medium that is conducted through the heat medium pipe 5a. One of the hot water storage tanks 24 is connected to the discharge side of the pump 21c, and the other is connected to the heat exchanger related to heat medium 15d.

The second pressure sensor 37 detects the pressure of the second heat source side refrigerant flowing out of the heating heat exchanger 15c. The second pressure sensor 37 is provided between the heating heat exchanger 15c and the suction side of the compressor 10b, similarly to the installation position of the fourth temperature sensor 38.
The 3rd pressure sensor 39 detects the pressure of the 1st heat source side refrigerant which flowed out of heat exchanger 15c for heating. The third pressure sensor 39 is provided on the downstream side of the heating heat exchanger 15c, similarly to the installation position of the fifth temperature sensor 40.

The fourth temperature sensor 38 detects the temperature of the second heat source side refrigerant flowing out of the heating heat exchanger 15c. Similar to the installation position of the second pressure sensor 37, the fourth temperature sensor 38 is provided between the heating heat exchanger 15c and the suction side of the compressor 10b.
The fifth temperature sensor 40 detects the temperature of the first heat source side refrigerant flowing out of the heating heat exchanger 15c. The fifth temperature sensor 40 is provided on the downstream side of the heat exchanger 15c for heating, similarly to the installation position of the third pressure sensor 39.
The sixth temperature sensor 41 detects the temperature of the second heat medium that has flowed out of the heat exchanger related to heat medium 15d. The sixth temperature sensor 41 is provided between the heat exchanger related to heat medium 15d and the suction side of the pump 21c.
In addition, the 4th temperature sensor 38, the 5th temperature sensor 40, and the 6th temperature sensor 41 are good to comprise, for example with a thermistor etc.

[First control device 80 and second control device 81]
The 1st control apparatus 80 and the 2nd control apparatus 81 are comprised by the microcomputer etc., the information (temperature information, pressure information) detected with the various detection apparatuses of the heat carrier converter 3, and the various detection apparatuses of the hot water supply apparatus 14 The operation of the compressors 10a, 10b, etc. can be comprehensively controlled based on the information detected in the above and instructions from the remote controller, and each operation mode to be described later can be executed. The first control device 80 and the second control device 81 can perform mutual control by exchanging information with each other.

Specifically, detection results of the first temperature sensor 31, the second temperature sensor 34, the third temperature sensor 35, and the pressure sensor 36 are output to the first control device 80, and the second control device 81 is output to the second control device 81. The detection results of the fourth temperature sensor 38, the fifth temperature sensor 40, the sixth temperature sensor 41, the second pressure sensor 37, and the third pressure sensor 39 are output. Then, the first control device 80 and the second control device 81 mutually exchange the detection result output to the first control device and the detection result output to the second control device 81, and perform overall control of the following operations. To do.
That is, the first control device 80 includes the driving frequency of the compressor 10a, the rotational speed (including ON / OFF) of a blower (not shown) attached to the heat source side heat exchanger 12, the opening degree of the expansion device 16, and the opening / closing device 17. Switching, switching of the first refrigerant flow switching device 11 and the second refrigerant flow switching device 18, driving frequency of the pump 21, switching of the first heat medium flow switching device 22, and second heat medium flow switching device 23 Switching, and the overall control of the opening degree of the heat medium flow control device 25 and the like. The second control device 81 performs overall control such as the drive frequency of the compressor 10b and the opening degrees of the expansion devices 16c and 16d.

  Although the installation position of the first control device 80 is described as being provided in the heat medium relay unit 3 in FIG. 2, it is not limited thereto, and may be provided for each unit, for example, outdoor It may be provided in the machine 1. Further, the installation position of the second control device 81 is preferably provided, for example, in the hot water supply device 14 as shown in FIG. Note that the first control device 80 and the second control device 81 are configured to be able to communicate with each other by wired or wireless communication so as to perform cooperative control.

In the air conditioner 100, the compressor 10a, the first refrigerant flow switching device 11, the heat source side heat exchanger 12, the switching device 17, the second refrigerant flow switching device 18, the heat exchanger related to heat medium 15 and heating The refrigerant circuit A is configured by connecting the first heat source side refrigerant flow path, the expansion device 16, the expansion device 16 c, and the accumulator 19 of the heat exchanger 15 c with the refrigerant pipe 4.
Further, the first heat medium flow path of the heat exchanger related to heat medium 15, the pump 21, the first heat medium flow path switching device 22, the heat medium flow control device 25, the use side heat exchanger 26, and the second heat medium flow The path switching device 23 is connected by the heat medium pipe 5 to constitute the heat medium circulation circuit B.
Then, a plurality of use side heat exchangers 26 are connected in parallel to each of the heat exchangers 15 between heat mediums, and the heat medium circulation circuit B is made into a plurality of systems.

Further, the compressor 10b, the second heat source side refrigerant flow path of the heating heat exchanger 15c, the second heat source side refrigerant flow path of the heat exchanger related to heat medium 15d, and the expansion device 16d are connected by a refrigerant pipe 4c. A refrigerant circulation circuit A2 is configured.
Furthermore, the heat medium circulation circuit B2 is configured by connecting the second heat medium flow path of the pump 21c, the hot water storage tank 24, and the heat exchanger related to heat medium 15d with the heat medium pipe 5a.

Therefore, in the air conditioner 100, the outdoor unit 1 and the heat medium relay unit 3 are connected via the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b provided in the heat medium converter 3. The heat medium relay unit 3 and the indoor unit 2 are also connected via the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b. Furthermore, the heat medium converter 3 and the hot water supply device 14 are connected via a heat exchanger 15c for heating provided in the hot water supply device 24, and the hot water supply device 14 and the hot water storage tank 24 are connected to the heat exchanger between heat media. 15d is connected.
That is, in the air conditioner 100, the first heat source side refrigerant circulating in the refrigerant circulation circuit A and the first heat medium circulating in the heat medium circulation circuit B in the intermediate heat exchanger 15a and the intermediate heat exchanger 15b. Heat exchange, the first heat source side refrigerant circulating in the refrigerant circulation circuit A in the heating heat exchanger 15c exchanges heat with the second heat source side refrigerant circulating in the refrigerant circulation circuit A2, and the intermediate heat exchanger 15d. Thus, the second heat source side refrigerant circulating in the refrigerant circuit A2 and the second heat medium circulating in the heat medium circuit B2 exchange heat.

  And the flow path of the 1st heat source side refrigerant | coolant and the flow path of the 2nd heat source side refrigerant | coolant are independent, and do not mutually mix. Also, the flow path of the first heat medium and the flow path of the second heat medium are independent and do not mix with each other.

  Next, each operation mode executed by the air conditioner 100 will be described. The air conditioner 100 can perform a cooling operation or a heating operation in the indoor unit 2 based on an instruction from each indoor unit 2. That is, the air conditioning apparatus 100 can perform the same operation for all the indoor units 2 and can perform different operations for each of the indoor units 2. In addition, the air conditioner 100 uses the heat of the first heat source side refrigerant in the first refrigeration cycle and the heat of the second heat source side refrigerant in the second refrigeration cycle to be stored in the hot water storage tank 24. 2 Heating medium can be heated.

  The operation mode executed by the air conditioner 100 includes a cooling only operation mode in which all the driven indoor units 2 execute a cooling operation, and a heating only operation in which all the driven indoor units 2 execute a heating operation. There are a cooling main operation mode in which the mode and the cooling load are larger, and a heating main operation mode in which the heating load is larger. In the heating only operation mode, the heating main operation mode, and the cooling main operation mode, the hot water supply device 14 is operated to heat the second heat medium. Below, each operation mode is demonstrated with the flow of a heat-source side refrigerant | coolant and a heat medium.

[Cooling operation mode]
FIG. 3 is a diagram for explaining the flow of the refrigerant and the heat medium during the cooling only operation of the air-conditioning apparatus 100 shown in FIG. In FIG. 3, the cooling only operation mode will be described by taking as an example a case where a cooling load is generated only in the use side heat exchanger 26a and the use side heat exchanger 26b. In FIG. 3, the pipes represented by thick lines indicate the pipes through which the refrigerant (first heat source side refrigerant) and the heat medium (first heat medium) flow. Moreover, in FIG. 3, the flow direction of the refrigerant is indicated by a solid line arrow, and the flow direction of the heat medium is indicated by a broken line arrow.

  In the cooling only operation mode shown in FIG. 3, in the outdoor unit 1, the first refrigerant flow switching device 11 is switched so that the heat source side refrigerant discharged from the compressor 10 a flows into the heat source side heat exchanger 12. In the heat medium converter 3, the pump 21a and the pump 21b are driven, the heat medium flow control device 25a and the heat medium flow control device 25b are opened, and the heat medium flow control device 25c and the heat medium flow control device 25d are fully closed. The first heat medium circulates between the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b and the use side heat exchanger 26a and the use side heat exchanger 26b. Note that the hot water supply device 14 is stopped in the cooling only operation mode.

First, the flow of the heat source side refrigerant in the refrigerant circuit A will be described.
The low-temperature / low-pressure first heat source side refrigerant is compressed by the compressor 10a and discharged as a high-temperature / high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 10 a flows into the heat source side heat exchanger 12 through the first refrigerant flow switching device 11. Then, the heat source side heat exchanger 12 condenses and liquefies while radiating heat to the outdoor air, and becomes a high-pressure liquid refrigerant. The high-pressure liquid refrigerant that has flowed out of the heat source side heat exchanger 12 flows out of the outdoor unit 1 through the check valve 13a, and flows into the heat medium relay unit 3 through the refrigerant pipe 4. The high-pressure liquid refrigerant that has flowed into the heat medium relay unit 3 is branched after passing through the opening / closing device 17a and expanded by the expansion device 16a and the expansion device 16b to become a low-temperature / low-pressure two-phase refrigerant.

  This two-phase refrigerant flows into each of the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b acting as an evaporator, and absorbs heat from the heat medium circulating in the heat medium circulation circuit B. It becomes a low-temperature, low-pressure gas refrigerant while cooling. The gas refrigerant flowing out of the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b flows out of the heat medium converter 3 via the second refrigerant flow switching device 18a and the second refrigerant flow switching device 18b. Then, the refrigerant flows into the outdoor unit 1 again through the refrigerant pipe 4. The refrigerant flowing into the outdoor unit 1 passes through the check valve 13d and is sucked into the compressor 10a again via the first refrigerant flow switching device 11 and the accumulator 19.

  At this time, the opening of the expansion device 16a is such that the superheat (superheat degree) obtained as the difference between the temperature detected by the third temperature sensor 35a and the temperature detected by the third temperature sensor 35b is constant. Be controlled. Similarly, the opening degree of the expansion device 16b is controlled so that the superheat obtained as the difference between the temperature detected by the third temperature sensor 35c and the temperature detected by the third temperature sensor 35d is constant. The opening / closing device 17a is open and the opening / closing device 17b is closed.

Next, the flow of the first heat medium in the heat medium circuit B will be described.
In the cooling only operation mode, the cold heat of the heat source side refrigerant is transmitted to the heat medium in both the heat exchanger 15a and the heat exchanger 15b, and the cooled heat medium is heated by the pump 21a and the pump 21b. The inside of the pipe 5 is allowed to flow. The heat medium pressurized and discharged by the pump 21a and the pump 21b passes through the second heat medium flow switching device 23a and the second heat medium flow switching device 23b, and the use side heat exchanger 26a and the use side heat exchange. Flows into the vessel 26b. The heat medium absorbs heat from the indoor air in the use side heat exchanger 26a and the use side heat exchanger 26b, thereby cooling the indoor space 7.

  Then, the heat medium flows out of the use side heat exchanger 26a and the use side heat exchanger 26b and flows into the heat medium flow control device 25a and the heat medium flow control device 25b. At this time, the heat medium flow control device 25a and the heat medium flow control device 25b control the flow rate of the heat medium to a flow rate necessary to cover the air conditioning load required in the room, so that the use-side heat exchanger 26a. And it flows into the use side heat exchanger 26b. The heat medium flowing out from the heat medium flow control device 25a and the heat medium flow control device 25b passes through the first heat medium flow switching device 22a and the first heat medium flow switching device 22b, and the heat exchanger related to heat medium 15a. And flows into the heat exchanger related to heat medium 15b, and is sucked into the pump 21a and the pump 21b again.

  In addition, in the heat medium pipe 5 of the use side heat exchanger 26, heat is generated in a direction from the second heat medium flow switching device 23 to the first heat medium flow switching device 22 via the heat medium flow control device 25. The medium is flowing. The air conditioning load required in the indoor space 7 includes the temperature detected by the first temperature sensor 31a, the temperature detected by the first temperature sensor 31b, and the temperature detected by the second temperature sensor 34. It is possible to cover by controlling so that the difference between the two is kept at the target value. As the outlet temperature of the heat exchanger related to heat medium 15, either the temperature of the first temperature sensor 31a or the first temperature sensor 31b may be used, or the average temperature thereof may be used. At this time, the first heat medium flow switching device 22 and the second heat medium flow switching device 23 ensure a flow path that flows to both the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b. In addition, the intermediate opening is set.

  When the cooling only operation mode is executed, it is not necessary to flow the heat medium to the use side heat exchanger 26 (including the thermo-off) without the heat load. The heat medium is prevented from flowing to the heat exchanger 26. In FIG. 3, a heat medium flows because there is a heat load in the use side heat exchanger 26a and the use side heat exchanger 26b, but in the use side heat exchanger 26c and the use side heat exchanger 26d, the heat load is passed. The corresponding heat medium flow control device 25c and heat medium flow control device 25d are fully closed. When a heat load is generated from the use side heat exchanger 26c or the use side heat exchanger 26d, the heat medium flow control device 25c or the heat medium flow control device 25d is opened to circulate the heat medium. That's fine.

[Heating operation mode]
FIG. 4 is a diagram for explaining the flow of the refrigerant and the heat medium during the heating only operation of the air-conditioning apparatus 100 shown in FIG. In FIG. 4, the heating only operation mode will be described by taking as an example a case where a thermal load is generated only in the use side heat exchanger 26a and the use side heat exchanger 26b. In FIG. 4, pipes represented by thick lines indicate the pipes through which the refrigerant (first heat source side refrigerant and second heat source side refrigerant) and the heat medium (first heat medium and second heat medium) flow. Moreover, in FIG. 4, the flow direction of the refrigerant is indicated by a solid line arrow, and the flow direction of the heat medium is indicated by a broken line arrow.

  In the heating only operation mode shown in FIG. 4, in the outdoor unit 1, the first refrigerant flow switching device 11 is used so that the first heat source side refrigerant discharged from the compressor 10 a does not pass through the heat source side heat exchanger 12. It switches so that it may flow in into the heat carrier converter 3. In the heat medium converter 3, the pump 21a and the pump 21b are driven, the heat medium flow control device 25a and the heat medium flow control device 25b are opened, and the heat medium flow control device 25c and the heat medium flow control device 25d are fully closed. The heat medium circulates between the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b and the use side heat exchanger 26a and the use side heat exchanger 26b. In the heating only operation mode, the operation of the hot water supply device 14 to heat the second heat medium is also included. In the description of the heating only operation mode here, it is assumed that the hot water supply device 14 is operating.

First, the flow of the heat source side refrigerant in the refrigerant circuit A will be described.
The low-temperature / low-pressure first heat source side refrigerant is compressed by the compressor 10a and discharged as a high-temperature / high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 10a passes through the first refrigerant flow switching device 11, conducts through the first connection pipe 4a, passes through the check valve 13b, and flows out of the outdoor unit 1. The high-temperature and high-pressure gas refrigerant that has flowed out of the outdoor unit 1 flows into the heat medium relay unit 3 through the refrigerant pipe 4. One of the high-temperature and high-pressure gas refrigerant that flows into the heat medium relay unit 3 and branches off before the opening / closing device 17 passes through the second refrigerant flow switching device 18a and the second refrigerant flow switching device 18b, It flows into each of the heat exchanger 15a and the heat exchanger 15b.

  The high-temperature and high-pressure gas refrigerant flowing into the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b is condensed and liquefied while dissipating heat to the heat medium circulating in the heat medium circulation circuit B, and becomes a high-pressure liquid refrigerant. . The liquid refrigerant flowing out of the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b is expanded by the expansion device 16a and the expansion device 16b to become a low-temperature, low-pressure two-phase refrigerant. The two-phase refrigerant flows out of the heat medium relay unit 3 through the opening / closing device 17b, and flows into the outdoor unit 1 through the refrigerant pipe 4 again. The two-phase refrigerant that has flowed into the outdoor unit 1 is conducted through the second connection pipe 4b, passes through the check valve 13c, and flows into the heat source side heat exchanger 12 that functions as an evaporator.

  Then, the two-phase refrigerant that has flowed into the heat source side heat exchanger 12 absorbs heat from the outdoor air in the heat source side heat exchanger 12 and becomes a low-temperature and low-pressure gas refrigerant. The low-temperature and low-pressure gas refrigerant that has flowed out of the heat source side heat exchanger 12 is again sucked into the compressor 10 a via the first refrigerant flow switching device 11 and the accumulator 19.

  At this time, the expansion device 16a has a constant subcool (degree of subcooling) obtained as a difference between a value obtained by converting the pressure detected by the pressure sensor 36 into a saturation temperature and a temperature detected by the third temperature sensor 35b. Thus, the opening degree is controlled. Similarly, the expansion device 16b has an opening degree so that a subcool obtained as a difference between a value obtained by converting the pressure detected by the pressure sensor 36 into a saturation temperature and a temperature detected by the third temperature sensor 35d is constant. Be controlled. The opening / closing device 17a is closed and the opening / closing device 17b is open. When the temperature at the intermediate position of the heat exchanger related to heat medium 15 can be measured, the temperature at the intermediate position may be used instead of the pressure sensor 36, and the system can be configured at low cost.

In addition, the other of the high-temperature and high-pressure gas refrigerant that has flowed into the heat medium converter 3, that is, the first heat source side refrigerant branched in front of the switchgear 17a that is closed of the heat medium converter 3, It flows out of the machine 3 and flows into the hot water supply device 14 through the refrigerant pipe 4. And the 1st heat source side refrigerant | coolant which flowed into the hot-water supply apparatus 14 transfers heat to the 2nd heat source side refrigerant | coolant with the heat exchanger 15c for a heating, is condensed and liquefied, and becomes a liquid refrigerant. The liquid refrigerant flowing out of the heating heat exchanger 15c is expanded by the expansion device 16c and becomes a gas-liquid two-phase refrigerant.
The gas-liquid two-phase refrigerant that has flowed out of the expansion device 16c flows out of the hot water supply device 14, flows into the heat medium relay unit 3 again through the refrigerant pipe 4, and merges with the refrigerant that has flowed out of the expansion device 16a and the expansion device 16b. .

  At this time, the opening degree of the expansion device 16c is controlled so that the subcool, which is the temperature difference between the detected temperature of the fifth temperature sensor 40 and the saturation temperature converted from the detected pressure of the third pressure sensor 39, is constant. The

The flow of the second heat source side refrigerant in the refrigerant circuit A2 will be described.
The second heat source side refrigerant is compressed by the compressor 10b and discharged as a high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 10b flows into the heat exchanger related to heat medium 15d. Then, the heat exchanger with heat exchanger 15d condenses while radiating heat to the second heat medium, and becomes a two-phase refrigerant. In the heat exchanger related to heat medium 15d, the second heat source side refrigerant dissipates heat to the second heat medium and heats the second heat medium.
The two-phase refrigerant that has flowed out of the heat exchanger related to heat medium 15d flows into the heating heat exchanger 15c through the expansion device 16d. The two-phase refrigerant that has flowed into the heating heat exchanger 15c is transferred with heat from the first heat source side refrigerant. In the heating heat exchanger 15c, the heat absorbed by the second heat source side refrigerant from the first heat source side refrigerant is consumed as the amount of heat for evaporating the second heat source side refrigerant. The gas refrigerant flowing out of the heating heat exchanger 15c is again sucked into the compressor 10b.

  At this time, the expansion device 16d controls the degree of opening so that the degree of superheat, which is the temperature difference between the detected temperature of the fourth temperature sensor 38 and the saturation temperature converted from the detected pressure of the second pressure sensor 37, is constant. Is done. Further, the rotation frequency of the compressor 10b is controlled so that the temperature detected by the sixth temperature sensor 41 becomes the target temperature.

The flow of the heat medium in the heat medium circuit B will be described.
In the heating only operation mode, the heat of the first heat source side refrigerant is transmitted to the first heat medium in both the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b, and the warmed first heat medium is transferred to the pump 21a. Then, the heat medium pipe 5 is caused to flow by the pump 21b. The first heat medium pressurized and discharged by the pump 21a and the pump 21b passes through the second heat medium flow switching device 23a and the second heat medium flow switching device 23b, and the utilization side heat exchanger 26a and utilization side It flows into the heat exchanger 26b. Then, the first heat medium radiates heat to the indoor air in the use side heat exchanger 26a and the use side heat exchanger 26b, thereby heating the indoor space 7.

  Then, the first heat medium flows out of the use-side heat exchanger 26a and the use-side heat exchanger 26b and flows into the heat medium flow control device 25a and the heat medium flow control device 25b. At this time, the flow rate of the first heat medium is controlled to a flow rate necessary to cover the load required indoors by the action of the heat medium flow rate adjusting device 25a and the heat medium flow rate adjusting device 25b, and the use side heat exchanger 26a, it flows into the use side heat exchanger 26b. The first heat medium flowing out of the heat medium flow control device 25a and the heat medium flow control device 25b passes through the first heat medium flow switching device 22a and the first heat medium flow switching device 22b, and performs heat exchange between heat media. Flows into the heat exchanger 15a and the heat exchanger related to heat medium 15b, and is sucked into the pump 21a and the pump 21b again.

  In the heat medium pipe 5 of the use side heat exchanger 26, the second heat medium flow switching device 23 passes through the heat medium flow control device 25 and reaches the first heat medium flow switching device 22. 1 Heat medium is flowing. The air conditioning load required in the indoor space 7 includes the temperature detected by the first temperature sensor 31a, the temperature detected by the first temperature sensor 31b, and the temperature detected by the second temperature sensor 34. It is possible to cover by controlling so that the difference between the two is kept at the target value. As the outlet temperature of the heat exchanger related to heat medium 15, either the temperature of the first temperature sensor 31a or the first temperature sensor 31b may be used, or the average temperature thereof may be used.

  At this time, the first heat medium flow switching device 22 and the second heat medium flow switching device 23 ensure a flow path that flows to both the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b. In addition, the intermediate opening is set. In addition, the usage-side heat exchanger 26a should be controlled by the temperature difference between the inlet and the outlet, but the temperature of the heat medium on the inlet side of the usage-side heat exchanger 26 is detected by the first temperature sensor 31b. By using the first temperature sensor 31b, the number of temperature sensors can be reduced and the system can be configured at low cost.

  When performing the heating only operation mode, since it is not necessary to flow the first heat medium to the use side heat exchanger 26 (including the thermo-off) without heat load, the flow path is closed by the heat medium flow control device 25, It is only necessary to prevent the heat medium from flowing to the use side heat exchanger 26.

The flow of the second heat medium in the heat medium circuit B2 will be described.
The heat of the second heat source side refrigerant is transmitted to the second heat medium by the heat exchanger related to heat medium 15d, and the heated second heat medium is caused to flow in the heat medium pipe 5a by the pump 21c. The second heat medium that has been pressurized and discharged by the pump 21 c flows into the hot water storage tank 24. The second heat medium that has flowed into the hot water storage tank 24 again flows into the heat exchanger related to heat medium 15d, and is then sucked into the pump 21c.

[Cooling operation mode]
FIG. 5 is a diagram for explaining the flow of the refrigerant and the heat medium during the cooling main operation of the air-conditioning apparatus 100 shown in FIG. In FIG. 5, the cooling main operation mode will be described by taking as an example a case where a cooling load is generated in the use side heat exchanger 26a and a heating load is generated in the use side heat exchanger 26b. In FIG. 5, pipes represented by bold lines indicate pipes through which the refrigerant (first heat source side refrigerant and second heat source side refrigerant) and the heat medium (first heat medium and second heat medium) circulate. . Further, in FIG. 5, the flow direction of the refrigerant is indicated by a solid line arrow, and the flow direction of the heat medium is indicated by a broken line arrow.

  In the cooling main operation mode shown in FIG. 5, in the outdoor unit 1, the first refrigerant flow switching device 11 is switched so that the heat source side refrigerant discharged from the compressor 10 a flows into the heat source side heat exchanger 12. In the heat medium converter 3, the pump 21a and the pump 21b are driven, the heat medium flow control device 25a and the heat medium flow control device 25b are opened, and the heat medium flow control device 25c and the heat medium flow control device 25d are fully closed. The first heat medium circulates between the heat exchanger related to heat medium 15a and the use side heat exchanger 26a, and between the heat exchanger related to heat medium 15b and the use side heat exchanger 26b. . The cooling main operation mode includes operating the hot water supply device 14 to heat the second heat medium. In the description of the cooling main operation mode here, it is assumed that the hot water supply device 14 is operated.

First, the flow of the first heat source side refrigerant in the refrigerant circuit A will be described.
The low-temperature / low-pressure first heat source side refrigerant is compressed by the compressor 10a and discharged as a high-temperature / high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 10 a flows into the heat source side heat exchanger 12 through the first refrigerant flow switching device 11. Then, the heat source side heat exchanger 12 condenses while radiating heat to the outdoor air, and becomes a two-phase refrigerant. The two-phase refrigerant that has flowed out of the heat source side heat exchanger 12 flows out of the outdoor unit 1 through the check valve 13a, and flows into the heat medium relay unit 3 through the refrigerant pipe 4. One of the two-phase refrigerant that has flowed into the heat medium relay unit 3 flows into the heat exchanger related to heat medium 15b that acts as a condenser through the second refrigerant flow switching device 18b.

  The two-phase refrigerant that has flowed into the heat exchanger related to heat medium 15b is condensed and liquefied while radiating heat to the first heat medium circulating in the heat medium circuit B, and becomes a liquid refrigerant. The liquid refrigerant flowing out of the heat exchanger related to heat medium 15b is expanded by the expansion device 16b and becomes a low-pressure two-phase refrigerant. This low-pressure two-phase refrigerant flows into the heat exchanger related to heat medium 15a acting as an evaporator via the expansion device 16a. The low-pressure two-phase refrigerant that has flowed into the heat exchanger related to heat medium 15a absorbs heat from the first heat medium circulating in the heat medium circuit B, and becomes a low-pressure gas refrigerant while cooling the first heat medium. The gas refrigerant flows out of the heat exchanger related to heat medium 15a, flows out of the heat medium converter 3 via the second refrigerant flow switching device 18a, and flows into the outdoor unit 1 again through the refrigerant pipe 4. The refrigerant flowing into the outdoor unit 1 passes through the check valve 13d and is sucked into the compressor 10a again via the first refrigerant flow switching device 11 and the accumulator 19.

  At this time, the opening degree of the expansion device 16b is controlled so that the superheat obtained as the difference between the temperature detected by the third temperature sensor 35c and the temperature detected by the third temperature sensor 35d becomes constant. The expansion device 16a is fully open, the opening / closing device 17a is closed, and the opening / closing device 17b is closed. The expansion device 16b controls the opening degree so that a subcool obtained as a difference between a value obtained by converting the pressure detected by the pressure sensor 36 into a saturation temperature and a temperature detected by the third temperature sensor 35d is constant. May be. Alternatively, the expansion device 16b may be fully opened, and the superheat or subcool may be controlled by the expansion device 16a.

In addition, the other of the two-phase refrigerant that has flowed into the heat medium converter 3, that is, the first heat source side refrigerant branched before the opening / closing device 17 a that is closed of the heat medium converter 3 is transferred from the heat medium converter 3. It flows out and flows into the hot water supply device 14 through the refrigerant pipe 4. And the 1st heat source side refrigerant | coolant which flowed into the hot-water supply apparatus 14 transfers heat to the 2nd heat source side refrigerant | coolant with the heat exchanger 15c for a heating, is condensed and liquefied, and becomes a liquid refrigerant. The liquid refrigerant flowing out of the heating heat exchanger 15c is expanded by the expansion device 16c and becomes a gas-liquid two-phase refrigerant.
The gas-liquid two-phase refrigerant that has flowed out of the expansion device 16c flows out of the hot water supply device 14, flows into the heat medium relay unit 3 again through the refrigerant pipe 4, and merges with the refrigerant that has flowed out of the expansion device 16b.

  At this time, the opening degree of the expansion device 16c is controlled so that the subcool, which is the temperature difference between the detected temperature of the fifth temperature sensor 40 and the saturation temperature converted from the detected pressure of the third pressure sensor 39, is constant. The

The flow of the second heat source side refrigerant in the refrigerant circuit A2 will be described.
The second heat source side refrigerant is compressed by the compressor 10b and discharged as a high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 10b flows into the heat exchanger related to heat medium 15d. Then, the heat exchanger with heat exchanger 15d condenses while radiating heat to the second heat medium, and becomes a two-phase refrigerant. In the heat exchanger related to heat medium 15d, the second heat source side refrigerant dissipates heat to the second heat medium and heats the second heat medium.
The two-phase refrigerant that has flowed out of the heat exchanger related to heat medium 15d flows into the heating heat exchanger 15c via the expansion device 16d, and the heat is transferred from the first heat source side refrigerant. In the heating heat exchanger 15c, the heat absorbed by the second heat source side refrigerant from the first heat source side refrigerant is consumed as the amount of heat for evaporating the second heat source side refrigerant. The gas refrigerant flowing out of the heating heat exchanger 15c is again sucked into the compressor 10b.

  At this time, the expansion device 16d controls the degree of opening so that the degree of superheat, which is the temperature difference between the detected temperature of the fourth temperature sensor 38 and the saturation temperature converted from the detected pressure of the second pressure sensor 37, is constant. Is done. Further, the rotation frequency of the compressor 10b is controlled so that the temperature detected by the sixth temperature sensor 41 becomes the target temperature.

The flow of the first heat medium in the heat medium circuit B will be described.
In the cooling main operation mode, the heat of the first heat source side refrigerant is transmitted to the first heat medium in the heat exchanger related to heat medium 15b, and the heated first heat medium is caused to flow in the heat medium pipe 5 by the pump 21b. It will be. In the cooling main operation mode, the heat of the heat source side refrigerant is transmitted to the first heat medium in the heat exchanger related to heat medium 15a, and the cooled first heat medium is caused to flow in the heat medium pipe 5 by the pump 21a. It will be. The first heat medium pressurized and discharged by the pump 21a and the pump 21b passes through the second heat medium flow switching device 23a and the second heat medium flow switching device 23b, and the utilization side heat exchanger 26a and utilization side It flows into the heat exchanger 26b.

  In the use side heat exchanger 26b, the first heat medium radiates heat to the indoor air, thereby heating the indoor space 7. Further, in the use side heat exchanger 26a, the first heat medium absorbs heat from the indoor air, thereby cooling the indoor space 7. At this time, the flow rate of the first heat medium is controlled to a flow rate necessary to cover the load required indoors by the action of the heat medium flow rate adjusting device 25a and the heat medium flow rate adjusting device 25b, and the use side heat exchanger 26a, it flows into the use side heat exchanger 26b. The first heat medium whose temperature has slightly decreased after passing through the use side heat exchanger 26b passes through the heat medium flow control device 25b and the first heat medium flow switching device 22b and flows into the heat exchanger related to heat medium 15b. It is sucked into the pump 21b again. The first heat medium whose temperature has slightly increased after passing through the use side heat exchanger 26a flows into the heat exchanger related to heat medium 15a through the heat medium flow control device 25a and the first heat medium flow switching device 22a. Then, it is sucked into the pump 21a again.

  In the heat medium pipe 5 of the use side heat exchanger 26, the first heat medium flow switching is performed from the second heat medium flow switching device 23 via the heat medium flow control device 25 on both the heating side and the cooling side. The first heat medium flows in the direction to the device 22. The air conditioning load required in the indoor space 7 is the difference between the temperature detected by the first temperature sensor 31b on the heating side and the temperature detected by the second temperature sensor 34 on the heating side, This can be covered by controlling the difference between the temperature detected by the two temperature sensor 34 and the temperature detected by the first temperature sensor 31a so as to keep the target value.

  When performing the cooling main operation mode, it is not necessary to flow the first heat medium to the use side heat exchanger 26 (including the thermo-off) without the heat load, so the flow path is closed by the heat medium flow control device 25, The first heat medium may be prevented from flowing to the use side heat exchanger 26.

The flow of the second heat medium in the heat medium circuit B2 will be described.
The heat of the second heat source side refrigerant is transmitted to the second heat medium by the heat exchanger related to heat medium 15d, and the heated second heat medium is caused to flow in the heat medium pipe 5a by the pump 21c. The second heat medium that has been pressurized and discharged by the pump 21 c flows into the hot water storage tank 24. The second heat medium that has flowed into the hot water storage tank 24 again flows into the heat exchanger related to heat medium 15d, and is then sucked into the pump 21c.

[Heating main operation mode]
FIG. 6 is a diagram for explaining the flow of the refrigerant and the heat medium during the heating-main operation of the air-conditioning apparatus 100 shown in FIG. In FIG. 6, the heating main operation mode will be described by taking as an example a case where a thermal load is generated only in the use side heat exchanger 26a and the use side heat exchanger 26b. In FIG. 6, pipes represented by thick lines indicate pipes through which the refrigerant (first heat source side refrigerant and second heat source side refrigerant) and the heat medium (first heat medium and second heat medium) flow. In FIG. 6, the flow direction of the refrigerant is indicated by a solid arrow, and the flow direction of the heat medium is indicated by a broken arrow.

  In the heating-main operation mode shown in FIG. 6, in the outdoor unit 1, the first refrigerant flow switching device 11 is used so that the first heat source side refrigerant discharged from the compressor 10 a does not pass through the heat source side heat exchanger 12. It switches so that it may flow in into the heat carrier converter 3. In the heat medium converter 3, the pump 21a and the pump 21b are driven, the heat medium flow control device 25a and the heat medium flow control device 25b are opened, and the heat medium flow control device 25c and the heat medium flow control device 25d are fully closed. The heat medium circulates between the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b and the use side heat exchanger 26a and the use side heat exchanger 26b. The heating main operation mode includes operating the hot water supply device 14 to heat the second heat medium. In the description of the heating main operation mode here, it is assumed that the hot water supply device 14 is operating.

First, the flow of the heat source side refrigerant in the refrigerant circuit A will be described.
The low-temperature / low-pressure first heat source side refrigerant is compressed by the compressor 10a and discharged as a high-temperature / high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 10a passes through the first refrigerant flow switching device 11, conducts through the first connection pipe 4a, passes through the check valve 13b, and flows out of the outdoor unit 1. The high-temperature and high-pressure gas refrigerant that has flowed out of the outdoor unit 1 flows into the heat medium relay unit 3 through the refrigerant pipe 4. One of the high-temperature and high-pressure gas refrigerant that flows into the heat medium relay unit 3 and branches off before the switchgear 17 passes through the second refrigerant flow switching device 18b and acts as a condenser between heat medium heat exchangers. Flows into 15b.

  The gas refrigerant flowing into the heat exchanger related to heat medium 15b is condensed and liquefied while dissipating heat to the first heat medium circulating in the heat medium circuit B, and becomes liquid refrigerant. The liquid refrigerant flowing out of the heat exchanger related to heat medium 15b is expanded by the expansion device 16b and becomes a low-pressure two-phase refrigerant. This low-pressure two-phase refrigerant flows into the heat exchanger related to heat medium 15a acting as an evaporator via the expansion device 16a. The low-pressure two-phase refrigerant flowing into the heat exchanger related to heat medium 15a evaporates by absorbing heat from the first heat medium circulating in the heat medium circulation circuit B, thereby cooling the first heat medium. This low-pressure two-phase refrigerant flows out of the heat exchanger related to heat medium 15a, flows out of the heat medium converter 3 via the second refrigerant flow switching device 18a, and flows again into the outdoor unit 1 through the refrigerant pipe 4. To do.

  The two-phase refrigerant that has flowed into the outdoor unit 1 passes through the check valve 13c and flows into the heat source side heat exchanger 12 that functions as an evaporator. Then, the two-phase refrigerant that has flowed into the heat source side heat exchanger 12 absorbs heat from the outdoor air in the heat source side heat exchanger 12 and becomes a low-temperature and low-pressure gas refrigerant. The low-temperature and low-pressure gas refrigerant that has flowed out of the heat source side heat exchanger 12 is again sucked into the compressor 10 a via the first refrigerant flow switching device 11 and the accumulator 19.

  At this time, the expansion device 16b has an opening degree so that a subcool obtained as a difference between a value obtained by converting the pressure detected by the pressure sensor 36 into a saturation temperature and a temperature detected by the third temperature sensor 35b is constant. Be controlled. Further, the expansion device 16a is fully opened, and the opening / closing devices 17a and 17b are closed. Note that the expansion device 16b may be fully opened, and the subcooling may be controlled by the expansion device 16a.

In addition, the other of the high-temperature and high-pressure gas refrigerant that has flowed into the heat medium converter 3, that is, the first heat source side refrigerant branched in front of the switchgear 17a that is closed of the heat medium converter 3, It flows out of the machine 3 and flows into the hot water supply device 14 through the refrigerant pipe 4. And the 1st heat source side refrigerant | coolant which flowed into the hot-water supply apparatus 14 transfers heat to the 2nd heat source side refrigerant | coolant with the heat exchanger 15c for a heating, is condensed and liquefied, and becomes a liquid refrigerant. The liquid refrigerant flowing out of the heating heat exchanger 15c is expanded by the expansion device 16c and becomes a gas-liquid two-phase refrigerant.
The gas-liquid two-phase refrigerant that has flowed out of the expansion device 16c flows out of the hot water supply device 14, flows into the heat medium relay unit 3 again through the refrigerant pipe 4, and merges with the refrigerant that has flowed out of the expansion device 16b.

  At this time, the opening degree of the expansion device 16c is controlled so that the subcool, which is the temperature difference between the detected temperature of the fifth temperature sensor 40 and the saturation temperature converted from the detected pressure of the third pressure sensor 39, is constant. The

The flow of the second heat source side refrigerant in the refrigerant circuit A2 will be described.
The second heat source side refrigerant is compressed by the compressor 10b and discharged as a high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 10b flows into the heat exchanger related to heat medium 15d. Then, the heat exchanger with heat exchanger 15d condenses while radiating heat to the second heat medium, and becomes a two-phase refrigerant. In the heat exchanger related to heat medium 15d, the second heat source side refrigerant dissipates heat to the second heat medium and heats the second heat medium.
The two-phase refrigerant that has flowed out of the heat exchanger related to heat medium 15d flows into the heating heat exchanger 15c via the expansion device 16d, and the heat is transferred from the first heat source side refrigerant. In the heating heat exchanger 15c, the heat absorbed by the second heat source side refrigerant from the first heat source side refrigerant is consumed as the amount of heat for evaporating the second heat source side refrigerant. The gas refrigerant flowing out of the heating heat exchanger 15c is again sucked into the compressor 10b.

  At this time, the expansion device 16d controls the degree of opening so that the degree of superheat, which is the temperature difference between the detected temperature of the fourth temperature sensor 38 and the saturation temperature converted from the detected pressure of the second pressure sensor 37, is constant. Is done. Further, the rotation frequency of the compressor 10b is controlled so that the temperature detected by the sixth temperature sensor 41 becomes the target temperature.

The flow of the heat medium in the heat medium circuit B will be described.
In the heating main operation mode, the heat of the first heat source side refrigerant is transmitted to the first heat medium by the heat exchanger related to heat medium 15b, and the heated first heat medium is caused to flow in the heat medium pipe 5 by the pump 21b. It will be. In the heating main operation mode, the cold heat of the heat source side refrigerant is transmitted to the first heat medium in the heat exchanger related to heat medium 15a, and the cooled first heat medium is caused to flow in the heat medium pipe 5 by the pump 21a. It will be. The first heat medium pressurized and flowing out by the pump 21a and the pump 21b passes through the second heat medium flow switching device 23a and the second heat medium flow switching device 23b to the use side heat exchanger 26a and the use side. It flows into the heat exchanger 26b.

  In the use side heat exchanger 26b, the first heat medium absorbs heat from the indoor air, thereby cooling the indoor space 7. Further, in the use side heat exchanger 26a, the first heat medium radiates heat to the indoor air, thereby heating the indoor space 7. At this time, the flow rate of the first heat medium is controlled to a flow rate necessary to cover the load required indoors by the action of the heat medium flow rate adjusting device 25a and the heat medium flow rate adjusting device 25b, and the use side heat exchanger 26a, it flows into the use side heat exchanger 26b. The first heat medium whose temperature has slightly increased after passing through the use side heat exchanger 26b flows into the heat exchanger related to heat medium 15a through the heat medium flow control device 25b and the first heat medium flow switching device 22b. Then, it is sucked into the pump 21a again. The first heat medium whose temperature has slightly decreased after passing through the use side heat exchanger 26a passes through the heat medium flow control device 25a and the first heat medium flow switching device 22a, flows into the heat exchanger related to heat medium 15b, It is sucked into the pump 21b again.

  In the heat medium pipe 5 of the use side heat exchanger 26, the first heat medium flow switching is performed from the second heat medium flow switching device 23 via the heat medium flow control device 25 on both the heating side and the cooling side. The first heat medium flows in the direction to the device 22. The air conditioning load required in the indoor space 7 is the difference between the temperature detected by the first temperature sensor 31b on the heating side and the temperature detected by the second temperature sensor 34 on the heating side, This can be covered by controlling the difference between the temperature detected by the two temperature sensor 34 and the temperature detected by the first temperature sensor 31a so as to keep the target value.

  When the heating main operation mode is executed, since it is not necessary to flow the first heat medium to the use side heat exchanger 26 (including the thermo-off) without the heat load, the heat medium flow control device 25 closes the flow path, The first heat medium may be prevented from flowing to the use side heat exchanger 26.

The flow of the second heat medium in the heat medium circuit B2 will be described.
The heat of the second heat source side refrigerant is transmitted to the second heat medium by the heat exchanger related to heat medium 15d, and the heated second heat medium is caused to flow in the heat medium pipe 5a by the pump 21c. The second heat medium that has been pressurized and discharged by the pump 21 c flows into the hot water storage tank 24. The second heat medium that has flowed into the hot water storage tank 24 again flows into the heat exchanger related to heat medium 15d, and is then sucked into the pump 21c.

[Temperature setting of hot water supply device 14]
In the hot water supply device 14, the temperature of the second heat medium is set to be higher than the target temperature of the first heat medium flowing through the use side heat exchangers 26a to 26d. This is because the second heat medium is used mainly to cover the hot water supply load. For example, the target temperature of the first heat medium flowing through the use side heat exchangers 26a to 26d is set to 50 ° C., and the target temperature of the second heat medium flowing through the heat exchanger related to heat medium 15d is set to a value such as 70 ° C.
Therefore, the condensation temperature or pseudo condensation temperature of the second heat source side refrigerant used in the hot water supply device 14 is higher than the condensation temperature or pseudo condensation temperature of the refrigerant circulating between the outdoor unit 1 and the heat medium relay unit 3. Controlled. For example, the condensation temperature or pseudo condensation temperature of the second heat source side refrigerant used in the hot water supply device 14 is 75 ° C., and the condensation temperature or pseudo condensation temperature of the refrigerant circulating between the outdoor unit 1 and the heat medium relay unit 3 is 55. It is controlled to a value such as ° C.

[About non-azeotropic refrigerants]
Inside the refrigerant pipe 4 in the first refrigeration cycle, for example, tetrafluoropropene (for example, HFO1234yf, HFO1234ze (E), etc.) represented by the chemical formula C ₃ H ₂ F ₄ and the chemical formula CH ₂ F are used. A mixed refrigerant containing difluoromethane (R32) represented by ₂ is mixed and circulated. As for HFO1234ze, there are two geometric isomers. There are a trans type in which F and CF ₃ are symmetrical with respect to a double bond, and a cis type on the same side. The physical properties are different. HFO1234ze (E) in this embodiment is a transformer type.

Since tetrafluoropropene has a double bond in the chemical formula, it is easily decomposed in the atmosphere, and has a low global warming potential (GWP) of about 4 (in the case of HFO1234yf), for example, and is an environmentally friendly refrigerant. However, since tetrafluoropropene has a lower density than the refrigerant such as R410A that has been adopted in the conventional air conditioner, if it is used alone as a refrigerant, a compressor is required to exert a large heating capacity and cooling capacity. Must be very large. Moreover, in order to prevent an increase in pressure loss in the piping, the refrigerant piping must also be made thick, resulting in an expensive air conditioner.
Thus, it is conceivable to employ a refrigerant in which R32 is mixed with tetrafluoropropene. This R32 is a refrigerant that is relatively easy to use because the characteristics of the refrigerant are close to those of conventional refrigerants. However, although it is smaller than the GWP 2088 of R410A, the GWP of R32 is relatively high at about 675. That is, from the viewpoint of environmental load, R32 is a refrigerant that is not suitable for use alone without being mixed with other refrigerants.

  Therefore, by using a refrigerant in which tetrafluoropropene and R32 are mixed, the characteristics of the refrigerant are improved without increasing the GWP so much, and an air conditioner that is easy for the global environment and efficient is obtained. be able to. As a mixing ratio of tetrafluoropropene and R32, it is conceivable to use the mixture by mass%, for example, 70% to 30%. However, the mixing ratio is not limited to this.

  However, since the boiling point of HFO1234yf is −29 (° C.) and the boiling point of R32 is −53.2 (° C.), the refrigerant obtained by mixing tetrafluoropropene and R32 is a non-azeotropic refrigerant having refrigerants having different boiling points. It becomes. For example, when this non-azeotropic refrigerant flows into a liquid reservoir such as the accumulator 19, a component having a lower boiling point stays as the liquid refrigerant. Thereby, the circulation composition of the refrigerant | coolant circulated through the piping of an air conditioning apparatus changes every moment.

[Temperature gradient in ph diagram of non-azeotropic refrigerant]
FIG. 7 is an explanatory diagram of a ph diagram (pressure-enthalpy diagram) of a predetermined non-azeotropic refrigerant. FIG. 8 is a case where a non-azeotropic refrigerant is employed as the first heat source side refrigerant and a single refrigerant is employed as the second heat source side refrigerant, and is an explanatory diagram of both refrigerant temperatures in the heating heat exchanger 15c. It is. FIG. 9 is an explanatory diagram of the temperature of both refrigerants in the heating heat exchanger 15c in the case where a non-azeotropic refrigerant is employed as the first heat source side refrigerant and the second heat source side refrigerant.
8 and 9 correspond to the flow path of the first heat source side refrigerant and the flow path of the second heat source side refrigerant of the heat exchanger 15c for heating. That is, the positive direction of the horizontal axis corresponds to the inlet side of the flow path of the first heat source side refrigerant, and the negative direction corresponds to the outlet side of the flow path of the first heat source side refrigerant. The positive direction of the horizontal axis corresponds to the outlet side of the flow path of the second heat source side refrigerant, and the negative direction corresponds to the inlet side of the flow path of the second heat source side refrigerant. The vertical axis | shaft of FIG.8 and FIG.9 has shown the temperature of the 1st heat source side refrigerant | coolant and the 2nd heat source side refrigerant | coolant.
In the following description, “the first heat source side refrigerant on the inlet side” refers to the first heat source side refrigerant flowing into the heating heat exchanger 15c, and “the first heat source side refrigerant on the outlet side” The 1st heat source side refrigerant | coolant which flows out out of the heat exchanger 15c for water shall be pointed out. The same applies to the second heat source side refrigerant.

As shown in FIG. 7, since non-azeotropic refrigerants have different boiling points, when the ph diagram is drawn, the saturated liquid temperature and the saturated gas temperature at the same pressure are different. That is, the saturated liquid temperature _{T L1} at the pressure P1 becomes lower temperature than the saturation gas temperature _{T G1} in the pressure P1. Thereby, the isotherm in the two-phase region of the ph diagram is inclined with a predetermined temperature gradient.
When the ratio of the mixed refrigerant is changed, the ph diagram becomes different and the temperature gradient changes. For example, when the mixing ratio of HFO1234yf and R32 is 70% to 30%, the temperature gradient is about 5.6 ° C. on the high pressure side and about 6.8 ° C. on the low pressure side. When the mixing ratio of HFO1234yf and R32 is 50% to 50%, the temperature gradient is about 2.5 ° C. on the high pressure side and about 2.8 ° C. on the low pressure side.
That is, assuming that the pressure loss is small, when the first heat source side refrigerant having the above mixing ratio is supplied to the heating heat exchanger 15c of the hot water supply device 14, the inlet of the heating heat exchanger 15c is obtained. The refrigerant temperature gradually decreases from the outlet toward the outlet.

  In the case of a refrigerant other than an azeotropic refrigerant, that is, a refrigerant such as a single refrigerant or a pseudo-azeotropic refrigerant, the circulatory composition of the refrigerant does not change. Is used for the phase change of the refrigerant and no temperature gradient occurs. That is, in the case of a refrigerant that is not a non-azeotropic refrigerant, the refrigerant temperature does not gradually decrease from the inlet to the outlet of the heat exchanger 15c for heating.

[Effect of non-azeotropic refrigerant mixture 1]
In the heat exchanger for heating 15c, the first heat source side refrigerant and the second heat source side refrigerant are counterflowing. That is, as for the positional relationship of the refrigerant, the first heat source side refrigerant on the inlet side corresponds to the second heat source side refrigerant on the outlet side, and the first heat source side refrigerant on the outlet side corresponds to the second heat source side refrigerant on the inlet side. It will be.

Here, it is assumed that a single refrigerant or a pseudo-azeotropic refrigerant mixture (for example, HFO1234yf) is adopted as the second heat source side refrigerant. In this case, as described in [Temperature gradient in ph diagram of non-azeotropic refrigerant], the saturated gas temperature and the saturated liquid temperature at the same pressure in the single refrigerant or the pseudo-azeotropic refrigerant are the same or nearly the same (temperature Therefore, the temperature of the second heat source side refrigerant passage in the heat exchanger 15c for heating is almost constant.
Specifically, the inlet side first heat source side refrigerant temperature and the outlet side second heat source side refrigerant temperature, the outlet side first heat source side refrigerant temperature, and the inlet side second heat source side refrigerant temperature are shown in FIG. As shown in Here, from the temperature difference between the saturated gas temperature on the inlet side and the outlet side saturated liquid temperature of the first heat source side refrigerant in the heating heat exchanger 15c, the outlet side of the second heat source side refrigerant in the heating heat exchanger 15c. The value obtained by subtracting the temperature difference between the saturated gas temperature and the inlet side temperature is large.
As described above, when a single refrigerant or a pseudo-azeotropic refrigerant mixture is used as the second heat source side refrigerant, the “subtracted value” becomes large and the heat exchange efficiency of the heat exchanger 15c for heating is reduced. The operating efficiency of the apparatus 14 will deteriorate.

Therefore, the air-conditioning apparatus 100 according to Embodiment 1 employs a non-azeotropic refrigerant mixture (for example, a refrigerant mixture of HFO1234yf and R32) as the second heat source side refrigerant. In a non-azeotropic refrigerant mixture, the saturated gas temperature at the same pressure is higher than the saturated liquid temperature (has a temperature gradient). Therefore, the second heat source side refrigerant temperature on the outlet side is higher than the second heat source side refrigerant temperature on the inlet side in the heat exchanger 15c for heating.
Specifically, the inlet side first heat source side refrigerant temperature and the outlet side second heat source side refrigerant temperature, the outlet side first heat source side refrigerant temperature, and the inlet side second heat source side refrigerant temperature are shown in FIG. As shown in
Here, from the temperature difference between the saturated gas temperature on the inlet side and the outlet side saturated liquid temperature of the first heat source side refrigerant in the heating heat exchanger 15c, the outlet side of the second heat source side refrigerant in the heating heat exchanger 15c. The “subtracted value” of the temperature difference between the saturated gas temperature and the inlet side temperature is smaller than the “subtracted value” in FIG. In addition, the “subtracted value” in FIG. 9 corresponds to the temperature difference between the two-phase portions of the first heat source side refrigerant and the second heat source side refrigerant (when the superheat degree is zero in the evaporator).
As described above, when a non-azeotropic refrigerant mixture is used as the second heat source side refrigerant, the “subtracted value” can be reduced and the heat exchange efficiency of the heat exchanger 15c for heating can be improved. Driving efficiency can be improved.

  However, since the gas-liquid mixed state two-phase refrigerant having a dryness of, for example, about 0.1 to 0.2 flows into the second heat source side refrigerant on the inlet side of the heating heat exchanger 15c, the heat exchange for heating The temperature difference between the outlet side temperature of the second heat source side refrigerant and the inlet side temperature of the second heat source side refrigerant in the vessel 15c is smaller than the temperature difference between the saturated gas temperature and the saturated liquid temperature.

[Effect 2 of non-azeotropic refrigerant mixture]
Next, the state of the first heat source side refrigerant and the second heat source side refrigerant in the heat exchanger 15c for heating will be described.
The first heat source side refrigerant becomes a gas part (gas phase) on the inlet side of the heating heat exchanger 15c and a liquid part (liquid phase) on the outlet side of the heating heat exchanger 15c. It is a two-phase part (gas-liquid two-phase). In addition, since the length of a gas part and a liquid part is not so long (compared with a two-phase part), and a heat transfer rate is also small, the contribution with respect to the total heat exchange amount is small. Therefore, most of the heat exchange of the heating heat exchanger 15c is performed in the two-phase portion of the first heat source side refrigerant.
Further, in the flow path of the second heat source side refrigerant in the heating heat exchanger 15c, the degree of superheat on the outlet side of the second heat source side refrigerant is controlled to a small value. Since the value of the degree of superheat is small and the heat transfer coefficient of the gas phase is small, most of the heat exchange of the heating heat exchanger 15c is performed in the two-phase portion of the second heat source side refrigerant.
Therefore, in the heat exchanger for heating 15c, the heat exchange between the two-phase portion of the first heat source side refrigerant and the two-phase portion of the second heat source side refrigerant accounts for most of the total heat exchange amount in the heat exchanger for heating 15c. is occupying.

Therefore, by reducing the temperature difference when the first heat source side refrigerant and the second heat source side refrigerant are in the two-phase state, the heat exchange efficiency of the heat exchanger 15c for heating can be improved. The operating efficiency of the device 14 can be improved. It should be noted that reducing the temperature difference in the two-phase state means that “the saturated gas temperature on the inlet side of the first heat source side refrigerant (the point at which the gas changes into two phases)” and “the saturated liquid temperature on the outlet side ( The temperature difference (the first temperature difference) between the two-phase to the liquid) and the saturated gas temperature on the outlet side of the second heat source side refrigerant in the heating heat exchanger 15c (the point where the two-phase changes to the gas). ) ”And“ inlet side temperature (for example, dryness of 0.1 to 0.2) ”, and the temperature difference between the first temperature difference and the first temperature difference is set to a small value. 2).
This state may be realized by adjusting the opening of the expansion device 16d so that the difference between the first temperature difference and the second temperature difference is less than or equal to a predetermined value. You may implement | achieve by adjusting the opening degree of the expansion apparatus 16d so that a difference may approach a 1st temperature difference. The “predetermined value” will be described later.

  Further, when the dryness of the two-phase refrigerant on the inlet side of the second heat source side refrigerant is not so large, for example, 0.1 to 0.2, the above-mentioned first temperature difference and “second” It is also possible to make the temperature difference between the “saturated gas of the heat source side refrigerant (point changing from two phase to gas) temperature” and the “saturated liquid of the second heat source side refrigerant (point changing from two phase to liquid) temperature” close to the value. The heat exchange efficiency of the heat exchanger 15c for heating can be improved, and the operating efficiency of the hot water supply device 14 can be improved.

[Effect 3 of non-azeotropic refrigerant mixture]
FIG. 10 is an explanatory diagram of the temperature difference (corresponding to the temperature gradient shown in FIG. 7) between the saturated gas and the saturated liquid at the same pressure of the non-azeotropic refrigerant (HFO1234yf and R32) supplied to the heating heat exchanger 15c. It is.
In FIG. 10, the horizontal axis indicates the ratio of R32 in the mixed refrigerant, and the vertical axis indicates the temperature difference of the refrigerant. The “condensation side” corresponds to the side on which the first heat source side refrigerant is condensed in the heat exchanger 15c for heating, and the “condensation side temperature difference” is a saturation gas temperature of 45 at each mixing ratio. The temperature difference between the saturated gas and the saturated liquid at a pressure of ° C is shown.
The “evaporation side” corresponds to the side where the second heat source side refrigerant evaporates in the heating heat exchanger 15c, and the “evaporation side temperature difference” means that the saturation gas temperature is 5 at each mixing ratio. The temperature difference between the saturated gas and the evaporator inlet refrigerant at a pressure of ° C. is shown.
Furthermore, three examples of the temperature difference on the evaporation side of the heat exchanger 15c for heating are shown when the inlet dryness is “0.1”, “0.2”, and “saturated liquid”.

As shown in FIG. 10, in the non-azeotropic refrigerant mixture of HFO1234yf and R32, if the mixing ratio is the same (R32 in FIG. 10 is 0.5), the temperature of the saturated gas and saturated liquid on the evaporation side It can be seen that the difference is larger than the temperature difference between the saturated gas and the saturated liquid on the condensation side.
Even when the dryness of the second heat source side refrigerant is 0.1, the temperature difference on the evaporation side is larger than the temperature difference on the condensation side. That is, in the heating heat exchanger 15c, if the dryness of the inlet of the second heat source side refrigerant on the evaporation side is as small as about 0.1, the saturated gas and the saturated liquid of the second heat source side refrigerant on the evaporation side are reduced. The temperature difference is larger than the temperature difference between the saturated gas and the saturated liquid of the first heat source side refrigerant on the condensing side.
Further, when the dryness of the second heat source side refrigerant on the inlet side is 0.2, the temperature difference on the condensing side is larger than the temperature difference on the evaporating side. That is, in the heat exchanger for heating 15c, the temperature difference between the saturated gas and the saturated liquid of the first heat source side refrigerant on the condensation side is larger than the saturated gas and the saturated liquid of the second heat source side refrigerant on the evaporation side. A value slightly larger than the temperature difference.

Therefore, based on FIG. 10, for example, the ratio of the first heat source side refrigerant and the second heat source side refrigerant may be set as follows.
That is, when the ratio of R32 in the first heat source side refrigerant is 20%, the ratio of R32 in the second heat source side refrigerant is set to about 8% or about 24%. As shown in FIG. 10, when the ratio of R32 in the first heat source side refrigerant is 20%, the temperature difference between the saturated gas and the saturated liquid is 7.3 ° C., and the second heat source When the dryness of the side refrigerant is 0.1, the temperature difference can be set to about 7.3 degrees by setting the ratio of R32 of the second heat source side refrigerant to about 8% or about 24%. Because.

This is the “saturated gas temperature on the inlet side of the first heat source side refrigerant (point where the gas changes into two phases)” in the heating heat exchanger 15c described in [Effect 2 by non-azeotropic refrigerant mixture]. The temperature difference (first temperature difference) from the “saturated liquid temperature on the outlet side (the point at which the liquid phase changes from the two phases)” and the “saturated gas temperature on the outlet side of the second heat source side refrigerant in the heating heat exchanger 15c” Corresponding to making the temperature difference (second temperature difference) between “(point changing from two phases to gas)” and “temperature on the inlet side (for example, dryness 0.1 to 0.2)” close to the value. ing. Thereby, the heat exchange efficiency of the heat exchanger 15c for heating can be improved, and the operating efficiency of the hot water supply apparatus 14 can be improved.
Actually, even if there is a temperature difference within 1 ° C. between the two temperatures, there is no significant difference in the heat exchange efficiency. Therefore, for example, when the ratio of R32 in the first heat source side refrigerant is 20% and the dryness of the second heat source side refrigerant is 0.1, the ratio of R32 in the second heat source side refrigerant is 6 to 6%. What is necessary is just to set to 29%. Thereby, the first temperature difference and the second temperature difference can be kept within 1 ° C.
Moreover, when the inlet dryness of the second heat source side refrigerant is very small, the second heat source side refrigerant may be regarded as a saturated liquid. When the ratio of R32 in the first heat source side refrigerant is 20%, if the ratio of R32 in the second heat source side refrigerant is 6% or 28%, the first temperature difference and the second temperature difference When the ratio of R32 in the second heat source side refrigerant is 5 to 8% and 23 to 32%, the second temperature difference is kept within 1 ° C. of the first temperature difference. Can do.

  In this way, by filling the air conditioner 100 with the refrigerant so that the second temperature difference falls within 1 ° C. of the first temperature difference, and preferably these temperature differences are closer to each other, The heat exchange efficiency of the heat exchanger 15c for heating can be improved, and the operating efficiency of the hot water supply device 14 can be improved.

[Method of filling non-azeotropic refrigerant mixture]
So far, the mixing ratio of R32 and HFO1234yf of the first heat source side refrigerant and the second heat source side refrigerant has been described. Next, a method for filling the air-conditioning apparatus 100 with the refrigerant having the mixing ratio will be described.
As a method of filling the air-conditioning apparatus 100 with the refrigerant having a predetermined mixing ratio, the refrigerant filling the first refrigeration cycle and the refrigerant filling different composition ratios as the refrigerant filling the second refrigeration cycle are used. There is a method of filling using a cylinder.
For example, in a building multi-air conditioner such as the air conditioner 100, the first heat source side refrigerant is filled after the device is installed on site. More specifically, after the device is installed, the first refrigeration cycle is filled with the first heat source side refrigerant by the refrigerant cylinder whose ratio of R32 is 20%.
On the other hand, the second heat source side refrigerant is filled in the device in advance before shipment from the factory. More specifically, when the inlet dryness of the second heat source side refrigerant in the second heat source side refrigerant side flow path of the heat exchanger for heating 15c is 0.1, the second heat source is preliminarily set before shipping from the factory. The second refrigeration cycle is filled with the second heat source side refrigerant by the refrigerant cylinder whose ratio of R32 to the side refrigerant is about 8% or about 24%.

Thus, using the refrigerant cylinder in which R32 has a predetermined ratio, the first refrigeration cycle and the second refrigeration cycle are filled with the first heat source side refrigerant and the second heat source side refrigerant. The simplest. However, in reality, it is rare that two types of refrigerants having a predetermined ratio of R32, that is, a convenient ratio, are commercialized and distributed in the market.
For example, when only a refrigerant cylinder having a ratio of R32 of 20% is distributed in the market as a mixed refrigerant, the air conditioner 100 uses the first heat source side refrigerant and the second heat source side refrigerant as follows. It is good to fill.

For example, when only a refrigerant cylinder having a R32 ratio of 20% is distributed in the market as a mixed refrigerant, the refrigerant is charged into the first refrigeration cycle locally as a first heat source side refrigerant. . Here, it is assumed that the refrigerant having the R32 ratio of 24% is to be charged into the second refrigeration cycle as the second refrigerant.
At this time, the HFO 1234yf refrigerant cylinder and the R32 refrigerant cylinder are used in the factory, and the second refrigeration cycle is first filled with HFO 1234yf of 0.76 times the specified refrigerant amount, and then the specified refrigerant amount of 0 It is good to ship after filling 24 times R32 refrigerant.

Moreover, it may be difficult in a manufacturing process to fill with two types of refrigerant | coolants contained in a 2nd heat-source side refrigerant | coolant at a factory. In such a case, it is preferable to install a filling port in the piping constituting the second refrigeration cycle so that the refrigerant can be additionally charged later. As a result, HFO1234yf, which is 0.76 times the amount of the specified refrigerant, is shipped to the second refrigeration cycle by a refrigerant cylinder at the factory, and is then shipped 0.24 times the amount of the specified refrigerant by the R32 refrigerant cylinder. The R32 refrigerant can be additionally charged.
As described above, the air conditioner 100 fills the second refrigeration cycle with the second heat source side refrigerant so that the plurality of single refrigerants constituting the second heat source side refrigerant have a predetermined mixing ratio. By adopting the method, the difference between the first temperature difference and the second temperature difference can be kept below a predetermined value, and the first heat source side refrigerant flowing into the heating heat exchanger 15c and the second heat source The heat exchange efficiency with the side refrigerant can be improved.

[Refrigerant piping 4]
As described above, the air-conditioning apparatus 100 according to Embodiment 1 has several operation modes. In these operation modes, the heat source side refrigerant flows through the pipe 4 connecting the outdoor unit 1 and the heat medium relay unit 3.

[Heat medium piping 5]
In some operation modes executed by the air-conditioning apparatus 100 according to Embodiment 1, a heat medium such as water or antifreeze flows through the heat medium pipe 5 that connects the heat medium converter 3 and the indoor unit 2. Yes.

[Summary of Embodiment 1]
The air-conditioning apparatus 100 according to Embodiment 1 is a refrigerant that fills the second heat source side refrigerant in the second refrigeration cycle so that the plurality of single refrigerants constituting the second heat source side refrigerant have a predetermined mixing ratio. Since the filling method is adopted, the difference between the first temperature difference and the second temperature difference can be kept below a predetermined value, and the first heat source side refrigerant flowing into the heating heat exchanger 15c and the second temperature difference can be reduced. Heat exchange efficiency with the two heat source side refrigerant can be improved. And energy saving can be aimed at by the part which can improve heat exchange efficiency in this way.

Embodiment 2. FIG.
FIG. 11 is a circuit configuration example of the air-conditioning apparatus 200 according to Embodiment 2. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and differences from the first embodiment will be mainly described.
For example, in the case of the air-conditioning apparatus 100 according to Embodiment 1, the change in the condensation temperature, the change in the refrigerant circulation amount, the outlet temperature (hot water temperature) of the second heat medium supplied to the hot water storage tank 24 of the hot water supply device 14. The frequency of the compressor 10b of the second refrigeration cycle changes according to the target value, the change in the circulation flow rate of the second heat medium, and the like, and the inlet dryness of the second heat source side refrigerant flowing into the heating heat exchanger 15c May change.
Thus, when the inlet dryness of the second heat source side refrigerant changes, the inlet side second heat source side refrigerant temperature may change. That is, the temperature difference between the second heat source side refrigerant temperature on the outlet side and the second heat source side refrigerant temperature on the inlet side in the heat exchanger 15c for heating changes, that is, the second temperature difference may change. That is. And when this 2nd temperature difference changes, it will shift | deviate from the temperature difference of the 1st heat source side refrigerant | coolant, and it will lead to the deterioration of the heat exchange efficiency in the heat exchanger 15c for a heating.
Therefore, the air conditioning apparatus 200 according to Embodiment 2 can improve the heat exchange efficiency of the heating heat exchanger 15c even if the inlet dryness of the second heat source side refrigerant changes, and the hot water supply apparatus 14 It is possible to improve the operation efficiency of the.

  As shown in FIG. 11, in the air conditioner 200, an accumulator 19a is installed between the suction side of the compressor 10b of the second refrigeration cycle and the heat exchanger 15c for heating. The accumulator 19a can change the amount of the second heat source side refrigerant to be stored, thereby changing the circulation composition of the second heat source side refrigerant circulating in the second refrigeration cycle. Yes.

  Since HFO1234yf has a boiling point of −29 ° C. and R32 has a boiling point of −53.2 ° C., R32 evaporates first. Therefore, when the composition ratio at the time of filling is used as a reference, in the gas-liquid two-phase state, the refrigerant gas contains a lot of R32 and the refrigerant liquid contains a lot of HFO1234yf. Accordingly, when the second heat source side refrigerant in the gas-liquid two-phase state flows into the accumulator 19a, the liquid refrigerant is stored, so that HFO 1234yf having a higher boiling point is stored in the accumulator 19a more than R32. Become. That is, when the composition ratio at the time of filling is used as a reference, the circulation composition of the second heat source side refrigerant circulating in the second refrigeration cycle is in a state where there is a large amount of R32.

Therefore, for example, when the ratio of R32 of the first heat source side refrigerant in the first refrigeration cycle is 20%, the second heat source refrigerant of the second refrigeration cycle is charged so that the ratio of R32 is 8%. Sometimes, the refrigerant amount accumulated in the accumulator 19a is adjusted by adjusting the opening of the expansion device 16d, so that the "saturated gas side temperature of the second heat source side refrigerant" and the "two-phase refrigerant temperature on the inlet side of the second heat source side refrigerant". The second temperature difference, which is a temperature difference from “”, can be greatly adjusted.
Further, when the second heat source refrigerant of the second refrigeration cycle is filled so that the ratio of R32 is 24%, the refrigerant amount accumulated in the accumulator 19a is adjusted by adjusting the opening of the expansion device 16d. The temperature difference between the two can be adjusted small.
In other words, the accumulator 19a can adjust the second temperature difference large or the second temperature difference small, so even if the dryness of the second heat source side refrigerant changes. The second temperature difference can be kept within 1 ° C. with respect to the first temperature difference.

In the second embodiment, by using the saturated gas temperature and saturated liquid temperature calculated from the detected pressure of the second pressure sensor 37 and the detected temperature of the fourth temperature sensor 38, the opening degree of the expansion device 16d is changed. The degree of dryness of the second heat source side refrigerant flowing into the accumulator 19a is controlled to control the circulation composition.
At this time, from the temperature difference between the saturated gas temperature and the saturated liquid temperature of the second heat source side refrigerant, the degree of dryness of the inlet refrigerant of the second heat source side refrigerant of the heating heat exchanger 15c is assumed, and the heating heat exchanger A temperature difference between the saturated gas of 15c and the temperature of the inlet refrigerant of the second heat source side refrigerant may be estimated.

Further, the circulation composition can be accurately controlled by using the calculation result of the dryness of the second heat source side refrigerant flowing into the heating heat exchanger 15c.
Therefore, as shown in FIG. 11, a fourth pressure sensor 42 for detecting the pressure of the second heat source side refrigerant flowing out from the heat exchanger related to heat medium 15d, and a second heat source side refrigerant flowing out from the heat exchanger related to heat medium 15d. It is preferable to install a seventh temperature sensor 43 for detecting the temperature of. Then, from the detection results of the fourth pressure sensor 42 and the seventh temperature sensor 43, the enthalpy of the second heat source side refrigerant flowing out from the heat exchanger related to heat medium 15d is calculated, and from this, the second of the heating heat exchanger 15c is calculated. The dryness of the inlet refrigerant of the heat source side refrigerant is calculated and used to control the circulation composition.

In the description so far of the second embodiment, the difference between the first temperature difference and the second temperature difference is shifted due to the change in the dryness of the inlet of the second heat source side refrigerant circulating in the second refrigeration cycle. The case where the heat exchange efficiency in the heat exchanger 15c for heating deteriorates has been described.
On the other hand, the heat exchange efficiency in the heat exchanger 15c for heating may deteriorate due to the first heat source side refrigerant circulating in the first refrigeration cycle.
In the first refrigeration cycle, the amount of refrigerant required for the refrigeration cycle differs between the cooling only operation and the heating only operation. That is, a larger amount of refrigerant is required during the cooling only operation. Accordingly, surplus refrigerant is generated during the all-heating operation, and therefore, the surplus first heat source side refrigerant is stored in the accumulator 19.

Then, the composition of R32 contained in the circulating first heat source side refrigerant changes according to the amount stored in the accumulator 19. That is, as a result of the change in the first temperature difference that is the difference between the first heat source side refrigerant temperature on the outlet side and the first heat source side refrigerant temperature on the inlet side in the heat exchanger for heating 15c, the first temperature difference and There is a possibility that the difference from the second temperature difference is deviated, and the heat exchange efficiency in the heating heat exchanger 15c is deteriorated.
Therefore, the opening amount of the expansion device 16d may be controlled to change the storage amount of the second heat source side refrigerant in the accumulator 19a. As a result, the ratio of R32 and HFO1234yf of the second heat source side refrigerant circulating in the second refrigeration cycle changes, reducing the difference between the first temperature difference and the second temperature difference, and heating The heat exchange efficiency of the heat exchanger for heat 15c can be improved, and the operating efficiency of the hot water supply device 14 can be improved.

  In the first and second embodiments, when only the heating load or the cooling load is generated in the use side heat exchanger 26, the corresponding first heat medium flow switching device 22 and second heat medium flow switching device. 23 is set to an intermediate opening so that the heat medium flows through both the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b. Accordingly, both the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b can be used for the heating operation or the cooling operation, so that the heat transfer area is increased, and an efficient heating operation or cooling operation is performed. Can be done.

  Moreover, when the heating load and the cooling load are mixedly generated in the use side heat exchanger 26, the first heat medium flow switching device corresponding to the use side heat exchanger 26 performing the heating operation. 22 and the second heat medium flow switching device 23 are switched to flow paths connected to the heat exchanger related to heat medium 15b for heating, and the first heat medium corresponding to the use side heat exchanger 26 performing the cooling operation By switching the flow path switching device 22 and the second heat medium flow path switching device 23 to a flow path connected to the heat exchanger related to heat medium 15a for cooling, in each indoor unit 2, heating operation and cooling operation are performed. It can be done freely.

The first heat medium flow switching device 22 and the second heat medium flow switching device 23 described in the first and second embodiments are those that can switch a three-way flow path such as a three-way valve, and two-way such as an on-off valve. What is necessary is just to switch a flow path, such as combining two things which open and close a flow path.
In addition, the first heat medium can be obtained by combining two things that can change the flow rate of the three-way flow path such as a stepping motor drive type mixing valve and two things that can change the flow rate of the two-way flow path such as an electronic expansion valve. The flow path switching device 22 and the second heat medium flow path switching device 23 may be used. In this case, it is possible to prevent water hammer due to sudden opening and closing of the flow path.
Further, in the first and second embodiments, the case where the heat medium flow control device 25 is a two-way valve has been described as an example. You may make it install with a pipe | tube.

  Further, the use side heat medium flow control device 25 may be a stepping motor driven type that can control the flow rate flowing through the flow path, and may be a two-way valve or a device that closes one end of the three-way valve. In addition, as the use side heat medium flow control device 25, a device that opens and closes a two-way flow path such as an open / close valve may be used, and the average flow rate may be controlled by repeating ON / OFF.

  Although the second refrigerant flow switching device 18 is shown as a four-way valve, the present invention is not limited to this, and a plurality of two-way flow switching valves and three-way flow switching valves are used, You may comprise so that it may flow.

  In the first and second embodiments, it goes without saying that the same holds true even when only one use-side heat exchanger 26 and one heat medium flow control device 25 are connected. Of course, there is no problem even if a plurality of the diaphragm devices 16 having the same movement are installed. Further, the case where the heat medium flow control device 25 is built in the heat medium converter 3 has been described as an example. However, the heat medium flow control device 25 is not limited thereto, and may be built in the indoor unit 2. 3 and the indoor unit 2 may be configured separately.

  An example in which a mixed refrigerant of R32 and HFO1234yf is used as the first heat source side refrigerant and the second heat source side refrigerant, and a mixed refrigerant in which R32 is 20% and HFO1234yf is 80% is used as the first heat source side refrigerant. Of course, the mixing ratio is not limited to this, the refrigerant type is not limited to this, and non-azeotropic mixing such as R407C (R32: R125: R134a = 23%: 25%: 52%) A refrigerant or other non-azeotropic refrigerant mixture may be used, and the same effect is obtained.

  The first heat medium and the second heat medium may use the same heat medium or different ones. As the heat medium (the first heat medium and the second heat medium), for example, brine (antifreeze), water, a mixed solution of brine and water, a mixed solution of water and an additive having a high anticorrosion effect, or the like can be used. . Therefore, even if the heat medium leaks into the indoor space 7 through the indoor unit 2, a highly safe heat medium is used, which contributes to an improvement in safety.

  In general, the heat source side heat exchanger 12 and the use side heat exchangers 26a to 26d are equipped with a blower, and in many cases, condensation or evaporation is promoted by blowing air, but the present invention is not limited to this. For example, as the use side heat exchangers 26a to 26d, a panel heater using radiation can be used, and the heat source side heat exchanger 12 is a water-cooled type in which heat is transferred by water or antifreeze. Any material can be used as long as it can dissipate or absorb heat.

  In addition, here, the case where there are four usage-side heat exchangers 26a to 26d has been described as an example, but any number may be connected.

  Further, the case where there are two heat exchangers between heat mediums 15a and 15b has been described as an example, but of course, it is not limited to this, and if the heat medium can be cooled or / and heated, Any number may be installed.

  The number of pumps 21a and 21b is not limited to one, and a plurality of small-capacity pumps may be arranged in parallel.

  In addition, if the first refrigeration cycle or / and the second refrigeration cycle have a function of detecting the circulation composition, the control can be performed with higher accuracy. The circulation composition can be detected by calculation by measuring the pressure and temperature at the inlet and outlet of the expansion devices 16a, 16b, 16c, and 16d. The circulating composition of the refrigerant may be detected by other methods. In addition, the refrigerant circulation composition in the state where the refrigerant is not accumulated in the accumulator 19 or / and 19a is the refrigerant filling composition at the time of installation, etc., and from the operating state (measured values of the temperature and pressure of each part), The amount of refrigerant stored in the accumulator may be estimated, and the circulation composition may be calculated based on the estimated value.

In the first and second embodiments, the following configuration example has been described. That is, the compressor 10, the four-way valve (first refrigerant flow switching device) 11, and the heat source side heat exchanger 12 are accommodated in the outdoor unit 1. Further, the use side heat exchanger 26 is accommodated in the indoor unit 2, and the heat exchanger related to heat medium 15 and the expansion device 16 are accommodated in the heat medium converter 3. Further, the outdoor unit 1 and the heat medium converter 3 are connected by a set of two pipes, the first heat source side refrigerant is circulated between the outdoor unit 1 and the heat medium converter 3, and the indoor unit 2 Are connected to each other by a set of pipes, the first heat medium is circulated between the indoor unit 2 and the heat medium converter 3, and the heat exchanger 15 between the heat medium The description has been given by taking as an example a system for exchanging heat between the first heat source side refrigerant and the first heat medium. However, the air conditioners 100 and 200 are not limited thereto.
For example, the compressor 10, the four-way valve (first refrigerant flow switching device) 11, and the heat source side heat exchanger 12 are accommodated in the outdoor unit 1, and the load exchanges heat between the air in the air-conditioning target space and the first heat source side refrigerant. The side heat exchanger and the expansion device 16 are accommodated in the indoor unit 2, provided with a repeater formed separately from the outdoor unit 1 and the indoor unit 2, and a set of two between the outdoor unit 1 and the repeater Are connected to each other by connecting a pair of pipes between the indoor unit 2 and the relay unit, and the first heat source side refrigerant is circulated between the outdoor unit 1 and the indoor unit 2 via the relay unit. Therefore, the present invention can be applied to a direct expansion system capable of performing a cooling only operation, a heating only operation, a cooling main operation, and a heating main operation, and similar effects are obtained.

  Moreover, although it demonstrated as what can perform the air conditioning heating mixed operation here, it is not limited to this. One heat exchanger 15 and one expansion device 16 are connected to each other, and a plurality of use side heat exchangers 26 and heat medium flow control devices 25 are connected in parallel to perform either a cooling operation or a heating operation. Even if there is no configuration, the same effect is obtained. Moreover, it is a direct expansion system which circulates a refrigerant | coolant to an indoor unit, and the structure which can perform only either a cooling operation or a heating operation may be sufficient.

  DESCRIPTION OF SYMBOLS 1 Heat source machine (outdoor unit), 2 Indoor unit, 2a-2d Indoor unit, 3, 3a, 3b Heat-medium converter, 4 Refrigerant piping, 4a 1st connection piping, 4b 2nd connection piping, 5 Heat-medium piping, 6 Outdoor space, 7 indoor space, 8 space, 9 building, 10a compressor (first compressor), 10b compressor (second compressor), 11 four-way valve (first refrigerant flow switching device), 12 heat source side heat Exchanger, 13a to 13d check valve, 14 hot water supply device, 15a, 15b heat exchanger between heat media (first heat exchanger between heat media), 15c heat exchanger for heating, 15d heat exchanger between heat media (first 2 heat exchanger between heat medium), 16a, 16b, 16c throttle device (first throttle device), 16d throttle device (second throttle device), 17a, 17b switchgear, 18a, 18b second refrigerant flow switching device, 19 Accumulator (1st accumulator -), 19a accumulator (second accumulator), 21a-21c pump (heat medium delivery device), 22a-22d first heat medium flow switching device, 23a-23d second heat medium flow switching device, 24 hot water storage Tank, 25a to 25d Heat medium flow control device, 26a to 26d Use side heat exchanger, 31a and 31b First temperature sensor, 34a to 34d Second temperature sensor, 35a to 35d Third temperature sensor, 36 Pressure sensor, 37 First 2 pressure sensor, 38 4th temperature sensor, 39 3rd pressure sensor, 40 5th temperature sensor, 41 6th temperature sensor, 42 4th pressure sensor, 43 7th temperature sensor, 80 1st control device, 81 2nd control Apparatus, 100, 200 air conditioner, 100A air conditioner, A refrigerant circulation circuit, B heat medium circulation circuit .

The compressor 10a sucks the first heat source side refrigerant and compresses the first heat source side refrigerant to a high temperature / high pressure state. For example, the compressor 10a may be composed of an inverter compressor capable of capacity control. The compressor 10 a has a discharge side connected to the first refrigerant flow switching device 11 and a suction side connected to the accumulator 19. The compressor 10a corresponds to the first compressor.
The first refrigerant flow switching device 11 is configured so that the flow of the first heat source side refrigerant during the heating operation (in the heating only operation mode and the heating main operation mode) and the cooling operation (in the all cooling operation mode and the cooling main operation mode). ) To switch the flow of the first heat source side refrigerant. In FIG. 2, the first refrigerant flow switching device 11 connects the discharge side of the compressor 10 a and the first connection pipe 4 a and connects the heat source side heat exchanger 12 and the accumulator 19. The state is shown.

The check valve 13a is provided in the refrigerant pipe 4 between the heat source side heat exchanger 12 and the heat medium converter 3, and the check valve 13a is used only in a predetermined direction (direction from the outdoor unit 1 to the heat medium converter 3). It allows flow. The check valve 13b is provided in the first connection pipe 4a, and causes the refrigerant discharged from the compressor 10a during the heating operation to flow to the heat medium relay unit 3. The check valve 13c is provided in the second connection pipeline 4b, in which circulates the refrigerant returned from the relay unit 3 during the heating operation to the suction side of the compressor 10 a. The check valve 13d is provided in the refrigerant pipe 4 between the heat medium converter 3 and the first refrigerant flow switching device 11, and only in a predetermined direction (direction from the heat medium converter 3 to the outdoor unit 1). The refrigerant flow is allowed.

Specifically, detection results of the first temperature sensor 31, the second temperature sensor 34, the third temperature sensor 35, and the pressure sensor 36 are output to the first control device 80, and the second control device 81 is output to the second control device 81. The detection results of the fourth temperature sensor 38, the fifth temperature sensor 40, the sixth temperature sensor 41, the second pressure sensor 37, and the third pressure sensor 39 are output. Then, the first control device 80 and the second control device 81 mutually exchange the detection result output to the first control device 80 and the detection result output to the second control device 81, and control the following operations. It is something to control.
That is, the first control device 80 includes the driving frequency of the compressor 10a, the rotational speed (including ON / OFF) of a blower (not shown) attached to the heat source side heat exchanger 12, the opening degree of the expansion device 16, and the opening / closing device 17. Switching, switching of the first refrigerant flow switching device 11 and the second refrigerant flow switching device 18, driving frequency of the pump 21, switching of the first heat medium flow switching device 22, and second heat medium flow switching device 23 Switching, and the overall control of the opening degree of the heat medium flow control device 25 and the like. The second control device 81 performs overall control such as the drive frequency of the compressor 10b and the opening degrees of the expansion devices 16c and 16d.

Therefore, in the air conditioner 100, the outdoor unit 1 and the heat medium relay unit 3 are connected via the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b provided in the heat medium converter 3. The heat medium relay unit 3 and the indoor unit 2 are also connected via the heat exchanger related to heat medium 15a and the heat exchanger related to heat medium 15b. Furthermore, a heat medium relay unit 3 and the water heater 14 is connected through the heating heat exchanger 15c provided in the water heater 14, the water heater 14 and a hot water storage tank 24, the heat medium heat exchanger 15d is connected.
That is, in the air conditioner 100, the first heat source side refrigerant circulating in the refrigerant circulation circuit A and the first heat medium circulating in the heat medium circulation circuit B in the intermediate heat exchanger 15a and the intermediate heat exchanger 15b. Heat exchange, the first heat source side refrigerant circulating in the refrigerant circulation circuit A in the heating heat exchanger 15c exchanges heat with the second heat source side refrigerant circulating in the refrigerant circulation circuit A2, and the intermediate heat exchanger 15d. Thus, the second heat source side refrigerant circulating in the refrigerant circuit A2 and the second heat medium circulating in the heat medium circuit B2 exchange heat.

In the case of a refrigerant other than a non -azeotropic refrigerant mixture, that is, a refrigerant such as a single refrigerant or a pseudo-azeotropic refrigerant mixture, the circulation composition of the refrigerant does not change. The change is used for the phase change of the refrigerant, and no temperature gradient occurs. That is, in the case of a refrigerant that is not a non-azeotropic refrigerant, the refrigerant temperature does not gradually decrease from the inlet to the outlet of the heat exchanger 15c for heating.

This is the “saturated gas temperature on the inlet side of the first heat source side refrigerant (point where the gas changes into two phases)” in the heating heat exchanger 15c described in [Effect 2 by non-azeotropic refrigerant mixture]. The temperature difference (first temperature difference) from the “saturated liquid temperature on the outlet side (the point at which the liquid phase changes from the two phases)” and the “saturated gas temperature on the outlet side of the second heat source side refrigerant in the heating heat exchanger 15c” Corresponding to making the temperature difference (second temperature difference) between “(point changing from two phases to gas)” and “temperature on the inlet side (for example, dryness 0.1 to 0.2)” close to the value. ing. Thereby, the heat exchange efficiency of the heat exchanger 15c for heating can be improved, and the operating efficiency of the hot water supply apparatus 14 can be improved.
Actually, even if there is a temperature difference within 1 ° C. between the two temperatures, there is no significant difference in the heat exchange efficiency. Therefore, for example, when the ratio of R32 in the first heat source side refrigerant is 20% and the dryness of the second heat source side refrigerant is 0.1, the ratio of R32 in the second heat source side refrigerant is 6 to 6%. What is necessary is just to set to 29%. This makes it possible to fit the first temperature difference and the difference between the second temperature difference 1 ℃ within.
Moreover, when the inlet dryness of the second heat source side refrigerant is very small, the second heat source side refrigerant may be regarded as a saturated liquid. When the ratio of R32 in the first heat source side refrigerant is 20%, if the ratio of R32 in the second heat source side refrigerant is 6% or 28%, the first temperature difference and the second temperature difference When the ratio of R32 in the second heat source side refrigerant is 5 to 8% and 23 to 32%, the second temperature difference is kept within 1 ° C. of the first temperature difference. Can do.

Claims (5)

A first refrigeration cycle is formed by connecting first flow paths of a first compressor, a heat source side heat exchanger, a first expansion device, a first heat exchanger related to heat medium, and a heat exchanger for heating with a first refrigerant pipe. Configure
The second compressor, the second flow path of the heating heat exchanger, the second expansion device, and the second heat exchanger related to heat medium are connected by a second refrigerant pipe to constitute a second refrigeration cycle,
The first refrigerant charged in the first refrigeration cycle and the second refrigerant charged in the second refrigeration cycle are non-azeotropic mixed refrigerants having different saturated gas temperatures and saturated liquid temperatures at the same pressure,
In the refrigerant charging method of the air conditioner in which heat exchange is performed between the first refrigerant and the second refrigerant using the heat exchanger for heating.
The heating heat exchanger is configured such that the first refrigerant supplied to the first flow path of the heating heat exchanger and the second refrigerant supplied to the second flow path are opposed to each other. Connected to the first refrigerant pipe and the second refrigerant pipe;
The difference between the saturated gas temperature on the inlet side of the first refrigerant and the saturated liquid temperature on the outlet side in the heat exchanger for heating is a first temperature difference,
When the difference between the saturated gas temperature on the outlet side of the second refrigerant in the heat exchanger for heating and the temperature on the inlet side is the second temperature difference,
The second refrigerant is filled with the second refrigerant so that a plurality of single refrigerants constituting the second refrigerant have a predetermined mixing ratio, and the first temperature difference and the second temperature are filled. The refrigerant filling method for an air conditioner, characterized in that the difference from the difference is kept below a predetermined value. The first refrigerant is composed of two types of single refrigerants,
The second refrigerant is composed of the two types of single refrigerants;
After filling the second refrigeration cycle with one of the single refrigerants,
The refrigerant filling method for an air conditioner according to claim 1, wherein the second refrigeration cycle is filled with the other single refrigerant to make the second refrigerant have the predetermined ratio. Filling the second refrigeration cycle with the one single refrigerant in an amount smaller than the specified charging amount of the second refrigerant charged in the second refrigeration cycle, and shipping from the factory;
After the first refrigeration cycle and the second refrigeration cycle are installed on site, the second refrigeration cycle is set such that the refrigerant amount of the second refrigerant in the second refrigeration cycle becomes a specified refrigerant amount. The method of claim 2, wherein the other single refrigerant is additionally charged to the air conditioner. The one single refrigerant of the first refrigerant and the second refrigerant is HFO1234yf, and the other single refrigerant of the first refrigerant and the second refrigerant is R32, or the one of the one refrigerant The refrigerant charging method for an air conditioner according to claim 2 or 3, wherein the single refrigerant is a transformer type HFO1234ze, and the other single refrigerant is R32. An air-conditioning apparatus, wherein the refrigerant is filled by the refrigerant filling method according to any one of claims 1 to 4.

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