WO2011062349A1

WO2011062349A1 - Heat pump

Info

Publication number: WO2011062349A1
Application number: PCT/KR2010/004791
Authority: WO
Inventors: 진심원; 장용희; 김범석; 류병진
Original assignee: 엘지전자 주식회사
Priority date: 2009-11-20
Filing date: 2010-07-21
Publication date: 2011-05-26
Also published as: EP2325579B1; CN102072590A; EP2325579A3; EP2325579A2; KR101321549B1; WO2011062349A4; US20110120180A1; KR20110056060A; CN102072590B

Abstract

The present invention relates to a heat pump comprising a refrigerating cycle unit and a booster module. The refrigerating cycle unit comprises: a compressor in which a refrigerant is compressed; a first heat exchanger in which the refrigerant compressed by the compressor is condensed; an expansion device in which the refrigerant condensed by the first heat exchanger expands; and a second heat exchanger in which the refrigerant expanded by the expansion device evaporates. The booster module is connected to the refrigerating cycle to separate a refrigerant vapor from the refrigerant flowing from the first heat exchanger to the expansion device, compress the separated refrigerant vapor, and enable the compressed refrigerant to flow between the compressor and the first heat exchanger, or to compress the refrigerant evaporated in the second heat exchanger and enable the compressed refrigerant to flow between the compressor and the first heat exchanger. The heat pump of the present invention is advantageous in that heating ability can be conveniently improved, and optimum performance can be achieved in accordance with a variety of load conditions which might not be handled by a compressor of a refrigerating cycle unit alone.

Description

Heat pump

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump, and more particularly, to a heat pump having a compressor, a first heat exchanger, an expansion mechanism, and a second heat exchanger, through which a refrigerant is circulated, wherein the first heat exchanger can supply heat to a heat source.

In general, a heat pump is a device for cooling / heating a room using a refrigeration cycle unit including a compressor, a first heat exchanger, an expansion mechanism, and a second heat exchanger to create a more comfortable indoor environment for a user.

The heat pump as described above heats / cools the room by discharging the air in the room by the first heat exchanger or the second heat exchanger and then discharging the air into the room.

However, the heat pump according to the prior art may not be able to achieve sufficient cooling / heating capability due to temperature change or changes in the surrounding environment, and the user may replace the existing installed heat pump with a larger capacity heat pump or replace a new one. There is a problem of installing an additional heat pump.

The present invention has been made to solve the above problems of the prior art, an object of the present invention is to provide a heat pump that is connected to the booster module to enhance the performance of the refrigeration cycle unit.

Another object of the present invention is to provide a heat pump capable of injecting refrigerant gas into a booster compressor of a booster module to increase heating performance at low temperature conditions.

It is another object of the present invention to provide a heat pump capable of efficiently responding to a load while minimizing power consumption by enabling various operations according to the load.

According to an aspect of the present invention, a heat pump includes: a compressor in which a refrigerant is compressed, a first heat exchanger in which a refrigerant compressed in the compressor is condensed, and an expansion mechanism in which the refrigerant condensed in the first heat exchanger is expanded; A refrigeration cycle unit having a second heat exchanger through which the refrigerant expanded in the expansion mechanism is evaporated; The refrigerant connected to the refrigeration cycle unit is separated and compressed from the refrigerant flowing from the first heat exchanger to the expansion mechanism, and then flows between the compressor and the first heat exchanger or evaporates the refrigerant evaporated in the second heat exchanger. It includes a booster module for compressing and flowing between the compressor and the first heat exchanger.

The booster module includes a first booster expansion mechanism for expanding the refrigerant flowing in the first heat exchanger, a gas-liquid separator for separating a liquid refrigerant and a gaseous refrigerant among the refrigerants expanded in the first booster expansion mechanism, and the gas-liquid separator in And a second booster expansion mechanism for expanding the separated gaseous refrigerant, and a booster compressor for compressing the refrigerant expanded in the second booster expansion mechanism.

The booster module further includes a booster suction pipe for guiding the refrigerant evaporated in the second heat exchanger to be sucked into the booster compressor.

The booster module includes a gas-liquid separator suction pipe connecting the first booster expansion mechanism and the gas-liquid separator, a gaseous-phase refrigerant discharge pipe through which the gaseous refrigerant separated from the gas-liquid separator is guided to the second booster expansion mechanism, and the second booster. And a booster compressor suction pipe through which a refrigerant expanded by an expansion mechanism is sucked into the booster compressor, and a booster compressor discharge pipe through which the refrigerant discharged from the booster compressor is guided between the compressor and the first heat exchanger. The pipe connects the booster compressor suction pipe between the second heat exchanger and the compressor.

The booster module further includes a check valve installed in the booster suction pipe to prevent refrigerant of the booster compressor suction pipe from being sucked into the compressor through the booster suction pipe.

The first booster expansion mechanism is connected to the first heat exchanger and the first booster expansion mechanism suction pipe.

The gas-liquid separator is connected to the expansion mechanism and the gas-liquid separator outlet pipe.

The compressor is a variable displacement compressor, and the booster compressor is a constant speed compressor.

The booster compressor has a smaller capacity than the compressor.

The heat pump includes a control unit for controlling the compressor, the booster compressor, and the second booster expansion mechanism according to an operation mode.

The control unit drives the compressor in the normal load mode, stops the booster compressor, and seals the second booster expansion mechanism.

The control unit turns off the compressor in the partial load mode, drives the booster compressor, and seals the second booster expansion mechanism.

The control unit drives the compressor and the booster compressor in the multi operation mode, and seals the second booster expansion mechanism.

The control unit drives the compressor and the booster compressor in the gas injection mode, and opens the second booster expansion mechanism.

The first heat exchanger is a water refrigerant heat exchanger for exchanging refrigerant and water, and is connected to a heating unit for heating a room and a hot water supply unit for supplying hot water and a water circulation passage.

The heat pump according to the present invention configured as described above can be further coupled to the booster module refrigeration cycle unit, the heating capacity is insufficient or can easily increase the heating capacity in the cold district, a variety of difficult to cope only with the compressor of the refrigeration cycle unit It can cope with the load conditions to achieve the best performance, and there is an advantage to improve the performance at a minimum cost.

1 is a configuration diagram before a booster module is installed in a refrigeration cycle unit of an embodiment of a heat pump according to the present invention;

2 is a configuration diagram after the booster module is installed in the refrigeration cycle unit of the heat pump according to the embodiment of the present invention;

3 is a configuration diagram in which a hot water supply unit and a heating unit are connected to a refrigeration cycle unit of an embodiment of a heat pump according to the present invention;

4 is a front view when the booster module of one embodiment of the heat pump according to the present invention is installed to be separated from a refrigeration cycle unit,

5 is a front view when the booster module of one embodiment of the heat pump according to the present invention is mounted on a refrigeration cycle unit,

6 is a P-h diagram comparing a time when a booster module is not installed and a booster module of an embodiment of the heat pump according to the present invention;

7 is a control block diagram of an embodiment of a heat pump according to the present invention;

8 is a schematic structural diagram showing a refrigerant flow in a normal load mode of a heat pump according to an embodiment of the present invention;

9 is a schematic structural diagram showing a refrigerant flow in a partial load mode of an embodiment of a heat pump according to the present invention;

10 is a schematic configuration diagram showing a refrigerant flow in a multi-operation mode of a heat pump according to an embodiment of the present invention;

11 is a schematic configuration diagram showing a refrigerant flow in the gas injection mode of an embodiment of a heat pump according to the present invention;

12 is a configuration diagram after the booster module is installed in a refrigeration cycle unit according to another embodiment of the heat pump according to the present invention;

13 is a schematic configuration diagram showing a refrigerant flow in a normal load mode of another embodiment of a heat pump according to the present invention;

14 is a schematic configuration diagram showing a refrigerant flow in the gas injection mode of another embodiment of the heat pump according to the present invention;

15 is a configuration diagram before the booster module is installed in the refrigeration cycle unit according to another embodiment of the heat pump according to the present invention;

16 is a configuration diagram after the booster module is installed in the refrigeration cycle unit according to another embodiment of the heat pump according to the present invention.

1 is a configuration diagram before the booster module is installed in a refrigeration cycle unit of a heat pump according to an embodiment of the present invention, Figure 2 is a configuration diagram after the booster module is installed in a refrigeration cycle unit of a heat pump according to an embodiment of the present invention. 3 is a configuration diagram in which a hot water supply unit and a heating unit are connected to a refrigeration cycle unit of an embodiment of a heat pump according to the present invention;

The heat pump according to the present embodiment includes a refrigeration cycle unit 1 and a booster module 2.

The refrigeration cycle unit 1 may be used for indoor cooling / heating and hot water supply.

The booster module 2 may be configured such that the refrigeration cycle unit 1 does not sufficiently correspond to the indoor cooling / heating and hot water supply capacity, or the user wishes to increase the indoor cooling / heating capacity and hot water supply capacity. It can be installed to further increase heating capacity and hot water capacity.

The refrigeration cycle unit 1 includes a compressor 10 for compressing a refrigerant as shown in FIGS. 1 to 3, a first heat exchanger 14 for condensing the refrigerant compressed in the compressor 10, and a first heat exchanger. The expansion mechanism 16 may expand the refrigerant condensed in the air 14, and the second heat exchanger 18 in which the refrigerant expanded in the expansion mechanism 16 is evaporated.

The refrigeration cycle unit 1 may be installed for cooling, may be installed for heating, or may be installed for both cooling and heating.

The refrigeration cycle unit 1 is capable of heating the room by being discharged back to the room after the indoor air is blown into the first heat exchanger 14, and after the indoor air is blown into the second heat exchanger 18 It is possible to cool the room by being discharged back to the room.

That is, the refrigeration cycle unit 1 is capable of directly exchanging indoor air with one of the first heat exchanger 14 and the second heat exchanger 18, in which case the refrigeration cycle unit 1 is the first heat exchanger. One of the 14 and the second heat exchanger 18 may include an indoor fan for circulating the indoor air.

The refrigeration cycle unit 1 is composed of a water refrigerant heat exchanger in which one of the first heat exchanger 14 and the second heat exchanger 18 exchanges refrigerant and water, and a mixed air of indoor air and outdoor air is heated or cooled. The cooling / heating coil is connected to the water refrigerant heat exchanger and the water circulation flow path, and the water cools / heats the cooling / heating coil while circulating the water refrigerant heat exchanger and the cooling / heating coil, and the mixed air of indoor air and outdoor air is cooled. It is possible to be discharged into the room after being cooled / heated by a heating coil.

That is, the water heat-exchanged with the refrigerant in the refrigeration cycle unit 1 may be used in an air handling unit (AHU) that is discharged to the room after cooling / heating the mixed air of the indoor air and the outdoor air.

The refrigeration cycle unit 1 is composed of a water refrigerant heat exchanger in which one of the first heat exchanger 14 and the second heat exchanger 18 exchanges refrigerant and water, and the water heated or cooled in the water refrigerant heat exchanger is indoors. It can be used for cooling, heating, and hot water supply.

When the refrigeration cycle unit 1 is installed for cooling, the second heat exchanger 18 is composed of a water refrigerant heat exchanger, and a cooling unit for cooling the room is connected to the water refrigerant heat exchanger and the water circulation flow path, so that water is It is possible to cool the cooling unit while circulating the refrigerant heat exchanger and the cooling unit, and the cooling unit can cool the room.

When the refrigeration cycle unit 1 is installed for heating, the first heat exchanger 14 is composed of a water refrigerant heat exchanger, the heating unit for heating the room is connected to the water refrigerant heat exchanger and the water circulation passage, and the water is refrigerant It is possible to heat the heating unit while circulating the heat exchanger and the heating unit and the heating unit to heat the room.

When the refrigeration cycle unit 1 is installed for hot water supply, the first heat exchanger 14 is composed of a water refrigerant heat exchanger, the hot water supply unit for supplying hot water to the room is connected to the water refrigerant heat exchanger and the water circulation flow path, It is possible to heat the hot water supply unit while circulating the water refrigerant heat exchanger and the hot water supply unit, and the hot water supply unit to supply hot water to the room.

When the refrigeration cycle unit 1 is installed by cooling / heating / hot water supply, the first heat exchanger 14 is configured as a water refrigerant heat exchanger, and the water / cooling unit and the water circulation flow path where the water refrigerant heat exchanger cools / heats the room. Water is circulated in the water refrigerant heat exchanger and the cooling / heating unit to cool / heat the cooling / heating unit, and the water refrigerant heat exchanger is connected to the hot water supply unit that supplies the hot water to the room and the water circulation passage, so that the water is the water refrigerant heat exchanger. It is possible to heat the hot water supply unit while the gas circulates in the hot water supply unit.

That is, the water heat exchanged with the refrigerant in the refrigerating cycle unit 1 may be used in a heating unit for heating the room, may be used in a cooling unit for cooling the room, and may be used in a hot water supply unit for supplying hot water to the room. Can be.

Hereinafter, in the refrigeration cycle apparatus 1, the first heat exchanger 14 is configured as a water refrigerant heat exchanger, the water heated in the first heat exchanger 14 is used in the hot water supply unit 4, and the first heat exchanger ( It will be described that the water heated or cooled in 14 can be used in the cooling / heating unit 5.

In the heat pump according to the present embodiment, the compressor 10, the first heat exchanger 14, the expansion mechanism 16, and the second heat exchanger 18 may be installed in the refrigeration cycle unit 1, and the refrigeration cycle unit (1) may further include a cooling / heating switching valve 12 capable of switching cooling / heating.

The cooling / heating switching valve 12 allows the refrigerant compressed in the compressor 10 to flow to the first heat exchanger 14 in the heating mode, and the refrigerant evaporated in the second heat exchanger 18 to the compressor 10. The flow causes the refrigerant to condense in the first heat exchanger 14 and the refrigerant to evaporate in the second heat exchanger 18.

In the cooling / heating switching valve 12, in the cooling mode or the defrost mode, the refrigerant compressed by the compressor 10 flows to the second heat exchanger 18, and the refrigerant evaporated in the first heat exchanger 14 is compressed by the compressor 10. ) To allow the refrigerant to evaporate in the first heat exchanger 14 and to condense the refrigerant in the second heat exchanger 18.

The refrigeration cycle unit 1 may be constituted by one unit or may be constituted by an indoor unit 6 and an outdoor unit 7.

When the refrigeration cycle unit 1 is composed of one unit, the compressor 10, the cooling / heating switching valve 12, the condenser 14, the expansion mechanism 16, and the second heat exchanger 18 are one case. It can be installed inside.

When the refrigeration cycle unit 1 is composed of an indoor unit 6 and an outdoor unit 7, the outdoor unit 7 includes a compressor 10, a cooling / heating switching valve 12, an expansion mechanism 16, and a second heat exchanger ( 18), the indoor unit 6 may include the first heat exchanger 14, and the outdoor unit 7 and the indoor unit 6 may be connected to the refrigerant pipe.

The compressor 10 may be connected to the cooling / heating switching valve 12 and the compressor discharge pipe 11.

The compressor discharge pipe 11 may be provided with a check valve 11 ′ that prevents refrigerant discharged from the booster compressor 90, which will be described later, from entering the compressor 10.

The cooling / heating switching valve 12 may be connected to the first heat exchanger 14 and the first heat exchanger-cooling / heating switching valve connecting pipe 13, and may be connected to the compressor 10 and the compressor suction pipe 20. have.

The first heat exchanger 14 may be connected to the expansion mechanism 16 and the first heat exchanger-expansion mechanism connecting pipe 15.

The first heat exchanger 14 may be configured as a water refrigerant heat exchanger in which the refrigerant and water are heat-exchanged, and a heat dissipation passage for radiating heat while the refrigerant passes, and an endothermic passage for absorbing water as the refrigerant passes therethrough may be formed between the heat transfer members. .

The first heat exchanger 14 may be connected to the water circulation channel 22 forming a closed circuit with the hot water supply unit 4 and the heating unit 5.

The expansion mechanism 16 may be connected to the second heat exchanger 18 and the expansion mechanism-second heat exchanger connecting pipe 17.

The expansion mechanism 16 may be made of an electronic expansion valve.

The second heat exchanger 18 may be connected to the cooling / heating switching valve 12 and the second heat exchanger-cooling / heating switching valve connecting pipe 19.

The second heat exchanger 18 is composed of an air-cooled heat exchanger in which outdoor air is blown to the second heat exchanger 18 so that the refrigerant is evaporated by the outdoor air, and the refrigeration cycle unit 1 supplies the outdoor air to the second heat exchanger ( 18) may further include an outdoor fan (not shown) for blowing to.

The water circulation passage 22 is configured such that the water heat-exchanged with the refrigerant in the first heat exchanger 14 is recovered to the first heat exchanger 14 after passing through at least one of the hot water supply unit 4 and the heating unit 5. 1 The heat exchanger 14 and the hot water supply unit 4 and the heating unit 5 can be connected.

The water circulation passage 22 includes a refrigeration cycle unit pipe 23 positioned inside the refrigeration cycle unit 1, and a hot water supply pipe 24 through which the water heated in the first heat exchanger 14 passes through the hot water supply unit 4. ), A cooling / heating pipe 25 through which water heated in the first heat exchanger 14 passes through the cooling / heating unit 5, and a refrigeration cycle unit pipe 23. It may include a connection pipe 27 for connecting to the heating pipe 25.

The connection pipe 27 is provided with a water control valve 28 for guiding water heated or cooled in the first heat exchanger 14 to at least one of the hot water supply pipe 24 and the cooling / heating pipe 25. 24 and the heating pipe 25 may be connected to the water control valve 28 through the connection pipe (27).

Hereinafter, the refrigeration cycle unit 1, the hot water supply unit 4, and the heating unit 5 will be described in detail.

The refrigeration cycle unit 1 is an air to water heat pump (AWHP), a flow switch 32 for detecting the flow of water passing through the refrigeration cycle unit piping 23, and the refrigeration cycle unit An expansion tank 33 installed at a position spaced apart from the flow switch 31 in the pipe 23, a water collecting tank 34 to which the refrigeration cycle unit pipe 23 is connected, and an auxiliary heater 35 is installed therein, and a refrigeration tank. It may include a circulation pump 36 installed in the cycle unit pipe 23 to pump the water to circulate.

The expansion tank 33 is a type of buffer that absorbs when the volume of heated water passes through the first heat exchanger 14 when it is expanded to an appropriate level or more, and is filled with nitrogen and moves in response to the volume of water. Flam may be installed.

The collecting tank 34 is water collected, and the auxiliary heater 35 may be selectively operated when the defrosting operation or the heat amount of the first heat exchanger 14 does not reach the required heat amount.

The water pump 36 causes water to circulate in the refrigeration cycle unit 1, the hot water supply unit 4, and the heating unit 5, which is to be installed after the water collection tank 34 in the refrigeration cycle unit piping 23. Can be.

The hot water supply unit 4 supplies hot water required for washing the face, bathing or washing dishes, etc., and may include a hot water tank 41 in which water is contained and an auxiliary heater 42 for hot water installed in the hot water tank 41. have.

The hot water supply tank 41 may be connected to a cold water inlet 43 in which cold water is supplied to the hot water supply tank 41, and a hot water outlet 44 in which hot water from the hot water tank 41 is discharged.

The hot water supply tank 41 is provided with a hot water supply pipe 24 to heat the water in the hot water tank 41.

The hot water outlet 44 may be connected to a hot water outlet 45 such as a shower.

The cold water inlet unit 46 may be connected to the hot water outlet unit 44 so that the cold water may be withdrawn from the hot water outlet unit 45.

The heating unit 5 may include a floor cooling / heating unit 51 for cooling / heating the floor of the room, and an air cooling / heating unit 52 for cooling / heating the air of the room.

The floor cooling / heating unit 51 may be buried in a meander line on the indoor floor.

The air cooling / heating unit 52 may be configured as a fan coil unit or a radiator.

In the cooling / heating pipe 25, water control valves 53 and 54 for guiding water to at least one of the floor cooling / heating unit 51 and the air cooling / heating unit 52 may be installed. The heating unit 51 is connected to the water control valves 53 and 54 and the air cooling / heating piping 55, and the floor cooling / heating unit 51 is the water control valves 53 and 54 and the floor cooling / It may be connected to the heating pipe 56.

When the water control valve 28 is in the hot water supply mode when the circulation pump 36 is driven, the water heated in the first heat exchanger 14 passes through the refrigeration cycle unit pipe 23 and the connection pipe 27 in order to supply the hot water. After flowing into the pipe 24, the water in the hot water tank 41 may be heated, and then sequentially passed through the connection pipe 27 and the refrigeration cycle unit pipe 23 to be recovered to the first heat exchanger 14.

When the circulation pump 36 is driven, if the water control valve 28 is in the cooling / heating mode, the water heated or cooled in the first heat exchanger 14 is connected to the refrigeration cycle unit pipe 23 and the connection pipe 27. Passed in order to flow into the cooling / heating pipe (25), heating or cooling at least one of the floor cooling / heating unit (51) and the air cooling / heating unit (52), and then connected to the cooling / heating pipe (25) After passing through the 27 and the refrigeration cycle unit pipe 23, the first heat exchanger 14 may be recovered.

At this time, when the

water control valves

55 and 56 are in the air cooling / heating mode, the water heated or cooled in the first heat exchanger 14 is air cooled / heated pipe 25 and air cooled / heated unit 52. And the air cooling / heating pipe (55) pass in order to exit the cooling / heating pipe (25), and in the bottom cooling / heating mode, the water heated in the first heat exchanger (14) is the bottom cooling / heating pipe (56). After passing through the bottom cooling / heating unit 51 and the bottom cooling / heating pipe 56, the water may be discharged to the cooling / heating pipe 25.

The booster module 2 may be additionally installed in the refrigeration cycle unit 1 as needed after the refrigeration cycle unit 1 is installed.

The booster module 2 is connected to the refrigeration cycle unit 1 to separate and compress the gaseous refrigerant from the refrigerant flowing from the first heat exchanger 14 to the expansion mechanism 16, and then compresses the compressor 10 and the first heat exchanger. It can flow between (14).

The booster module 2 has a booster compressor 90, which will be described later, compresses the refrigerant separately from the compressor 10 of the refrigeration cycle unit 1, and is higher than the condensing pressure of the first heat exchanger 14 and the second heat exchanger 18. The gaseous refrigerant having a medium pressure lower than the evaporation pressure may be injected into the booster compressor 90 to increase operating efficiency.

The booster module 2 separates the first booster expansion mechanism 62 that expands the refrigerant condensed in the first heat exchanger 14, and the liquid refrigerant and the gaseous refrigerant among the refrigerants expanded by the first booster expansion mechanism 62. The gas-liquid separator 70, the second booster expansion mechanism 80 for expanding the gaseous phase refrigerant separated by the gas-liquid separator 70, and the booster compressor 90 for compressing the refrigerant expanded in the second booster expansion mechanism 80. ) May be included.

In the heat pump according to the present embodiment, when the booster module 2 is installed, each of the first heat exchanger-cooling / heating switching valve connection pipe 13 and the first heat exchanger-expansion mechanism connection pipe 15 are separated. , The booster module 2 is connected to the separated first heat exchanger-cooling / heating switching

valve connecting pipe

13A, 13B, and connected to the separated first heat exchanger-expansion

mechanism connecting pipe

15A, 15B. Can be.

The first booster expansion device 62 may be connected to the first heat exchanger 14 and the first booster expansion device suction pipe 64, and the first booster expansion device suction pipe 64 may be separated from the first heat exchanger. It may be connected to any one 15A of the expansion mechanism connecting pipe (15A) (15B).

The first booster expansion mechanism 62 may be an electronic expansion valve.

The gas-liquid separator 70 separates the gaseous refrigerant from the refrigerant condensed in the first heat exchanger 14 with the liquid refrigerant, and may be connected to the expansion mechanism 16 and the gas-liquid separator outlet pipe 72, and the gas-liquid separator outlet pipe. 72 may be connected to the other one 15B of the separated first heat exchanger-expansion

mechanism connecting pipes

15A and 15B.

The second booster expansion mechanism 80 allows the gaseous refrigerant of the gas-liquid separator 70 to flow into the booster compressor 90 when opened, and prevents the gaseous refrigerant of the gas-liquid separator 70 from flowing to the booster compressor 90 when closed. do. The second booster expansion mechanism 80 may expand the gaseous refrigerant flowing from the gas-liquid separator 70 toward the booster compressor 90 when the opening degree is adjusted.

The second booster expansion mechanism 80 may be made of an electronic expansion valve.

The booster module 2 may include a gas-liquid separator suction pipe 74 connecting the first booster expansion mechanism 62 and the gas-liquid separator 70.

That is, the first heat exchanger 14 and the expansion mechanism 16 may be connected through the first heat exchanger-expansion mechanism connecting pipe 15 before the booster module 2 is installed, and the booster module 2 is installed. After that, any one of the first heat exchanger-expansion

mechanism connecting pipes

15A and 15B, 15A, the first booster expansion device suction pipe 64, the first booster expansion device 62, and the gas-liquid separator suction pipe 74 ), The gas-liquid separator 70, the gas-liquid separator outlet pipe 72 and the other one 15B of the first heat exchanger-expansion

mechanism connecting pipe

15A, 15B.

The booster module 2 includes a gaseous refrigerant discharge pipe 76 through which the gaseous phase refrigerant separated by the gas-liquid separator 70 is guided to the second booster expansion mechanism 80, and a refrigerant expanded by the second booster expansion mechanism 80. The booster compressor suction pipe 92 sucked into the booster compressor 90 and the refrigerant discharged from the booster compressor 90 are guided between the compressor 10 of the refrigeration cycle unit 1 and the first heat exchanger 14. The compressor discharge pipe (94, 95) may further include.

The booster compressor discharge pipe (94, 95) is a first booster compressor for connecting any one (13A) and the other (13B) of the separated first heat exchanger-cooling / heating switching valve connecting pipe (13A) (13B) The discharge pipe 94 and the second booster compressor discharge pipe 95 for guiding the refrigerant discharged from the booster compressor 90 to the first booster compressor discharge pipe 94 may be included.

That is, the cooling / heating switching valve 12 and the first heat exchanger 14 are connected to the first heat exchanger-cooling / heating switching valve connecting pipe 13 as shown in FIG. 1 before the booster module 2 is installed. 2) after the booster module 2 is installed, as shown in FIG. 2, either the first heat exchanger-cooling / heating switching

valve connecting pipe

13A or 13B (13A) and the first booster compressor The discharge pipe 94 may be connected to the other one 13B of the first heat exchanger-cooling / heating switching

valve connecting pipe

13A and 13B.

The booster

compressor discharge pipes

94 and 95 are provided with a check valve 95 'that prevents the refrigerant compressed by the compressor 10 from flowing into the booster compressor 90. The check valve 95' is a second booster. It may be installed in the compressor discharge pipe (95).

The booster module 2 further includes a bypass pipe 99 for allowing the refrigerant flowing from the gas-liquid separator 70 to the gas-liquid separator outlet pipe 72 to flow into the first booster expansion mechanism suction pipe 64. The bypass pipe 99 is provided with a check valve 99 'that prevents the refrigerant of the first booster expansion mechanism suction pipe 64 from flowing through the bypass pipe 99 to the gas-liquid separator outlet pipe 72, and the gas-liquid solution. The gaseous refrigerant flowing from the separator 70 to the booster compressor suction pipe 92 may be maximized.

The booster module 2 may compress the refrigerant evaporated in the second heat exchanger 18 in the booster compressor 90 and then flow between the compressor 10 and the first heat exchanger 14.

The booster module 2 may have a structure in which the gaseous refrigerant separated in the gas-liquid separator 70 and the refrigerant evaporated in the second heat exchanger 18 are together or selectively sucked into the booster compressor 90.

The booster module 2 connects the booster compressor suction pipe 92 between the second heat exchanger 18 and the compressor 10 and the booster suction pipe 96 so that the booster module 2 of the refrigerant evaporated in the second heat exchanger 18 is reduced. A portion may be directed to the booster compressor suction line 92.

One end of the booster suction pipe 96 may be connected to the compressor suction pipe 20, and the other end thereof may be connected to the booster compressor suction pipe 92.

The booster suction pipe 96 is connected to the first booster suction pipe 97 installed in the refrigeration cycle unit 1 to be connected to the compressor suction pipe 20 and to the booster module 2 to be connected to the booster compressor suction pipe 92. The second booster suction pipe 98 may be installed, and the third booster suction pipe 99 may be connected to the first booster suction pipe 97 and the second booster suction pipe 98.

The booster module 2 further includes a check valve 96 'installed in the booster suction pipe 96 to prevent refrigerant from the booster compressor suction pipe 92 from being sucked into the compressor 10 through the booster suction pipe 96. It may include.

The check valve 96 ′ may be installed in the second booster suction pipe 98.

4 is a front view when the booster module of one embodiment of the heat pump according to the present invention is installed to be separated from the refrigeration cycle unit, and FIG. 5 is the booster module of the embodiment of the heat pump according to the present invention to the refrigeration cycle unit. Front view.

When the refrigeration cycle unit 1 is composed of one unit, the booster module 2 may be installed to be spaced apart from the refrigeration cycle unit 1 or fastened to the refrigeration cycle unit 1.

When the refrigeration cycle unit 1 is composed of an indoor unit 6 and an outdoor unit 7, the booster module 2 may be installed to be spaced apart from the indoor unit 6 and the outdoor unit 7 or the indoor unit 6 and the outdoor unit 7. It can be installed to be fastened to either.

As shown in FIG. 4, the refrigeration cycle unit 1 may be installed to be separated from the refrigeration cycle unit 1 by being spaced apart from the outdoor unit 7, and as shown in FIG. 5, the outdoor unit 7. It may be integrated with the outdoor unit 7 and integrally formed with the refrigeration cycle unit 1.

That is, the booster module 5 may be selectively mounted to the outdoor unit O, as shown in FIGS. 4 and 5.

Figure 6 is a P-h diagram comparing the time when the booster module is not installed when the booster module of the heat pump according to an embodiment of the present invention.

When the booster module 2 is not installed, the refrigerant undergoes a typical compression, condensation, expansion, and evaporation process, as shown by a dotted line in FIG. 4, where a-> b '> c-> f-> a is performed. This is going on.

On the other hand, when the booster module 2 is additionally installed, the refrigerant undergoes the compression, condensation, expansion, expansion, and evaporation processes, as shown by the solid line in FIG. 6, where the cooling a-> b-> c-> d -> e-> f-> a, and part of the refrigerant flowing out of the first heat exchanger 14 is expanded and compressed in the booster module 2, d-> g- of FIG. In the process of> h-> b, the heat pump may reduce the compression work while increasing the overall efficiency than when the booster module 2 is not installed.

That is, the total power consumption supplied to the compressor 10 and the booster compressor 90 is reduced, and in particular, the low-temperature heating capability of the outdoor is low. In addition, when the booster module 2 is installed, the maximum management temperature of the compressor 10 may be relatively lower than when the booster module 2 is not installed, and the reliability of the compressor 10 may be improved.

Figure 7 is a control block diagram of one embodiment of a heat pump according to the present invention, Figure 8 is a schematic block diagram showing the refrigerant flow in the normal load mode of an embodiment of the heat pump according to the present invention, Figure 9 is in accordance with the present invention 10 is a schematic configuration diagram showing a refrigerant flow in a partial load mode of a heat pump according to one embodiment, and FIG. 10 is a schematic configuration diagram showing a refrigerant flow in a multi operation mode according to an embodiment of the present invention, and FIG. The heat pump according to the embodiment is a schematic block diagram showing the refrigerant flow in the gas injection mode.

The heat pump according to the present embodiment includes an operation unit 100 for inputting various commands such as operation / stop of the heat pump, a load detection sensor 110 for detecting a load of the heat pump, and an operation of the operation unit 100. The compressor 10, the expansion device 16, the outdoor fan 22, the first booster expansion device 62, the second booster expansion device 80, and the booster compressor 90 according to the detection result of the load detection sensor 110. The control unit 120 may further include a control unit.

The load sensor 110 may include a water temperature sensor that detects a load of the hot water supply unit 4 and the heating unit 5.

The water temperature sensor may be installed at one side of the water circulation passage 22 to sense a temperature of water circulating at least one of the hot water supply unit 4 and the heating unit 5 and the first heat exchanger 14.

The water temperature sensor is installed to detect the temperature of the water recovered to the first heat exchanger 14 after passing through at least one of the hot water supply unit 4 and the heating unit 5, and is installed in the refrigeration cycle unit piping 23 It is preferable.

The load sensor 110 may include an outdoor temperature sensor for detecting whether the outdoor temperature is low.

The outdoor temperature sensor may be installed in the second heat exchanger 18 to sense a temperature of outdoor air blown toward the second heat exchanger 18 outdoors.

When the load detection sensor 110 detects the load, the control unit 120 controls the partial load mode, the normal load mode, and the multi-operation mode, and when the load detection sensor 110 detects the outdoor low temperature load, the gas injection mode. Can be controlled by

If the temperature of the water detected by the load sensor 110 is less than the first set temperature, the controller 120 determines the load of the heat pump as a partial load, and the temperature of the water detected by the load sensor 110 is set to the first value. If the temperature is greater than the predetermined temperature higher than the first predetermined temperature and less than the second predetermined temperature, the load of the heat pump is determined as a normal load, and if the temperature of the water detected by the load detection sensor 110 is greater than or equal to the second predetermined temperature, the heat pump Can be determined as a multi-operation load (ie, overload).

The controller 120 may determine the load of the heat pump as the outdoor low temperature load when the outdoor temperature detected by the load detection sensor 110 is less than or equal to the set temperature.

The controller 120 may control the compressor 10, the booster compressor 90, and the second booster expansion mechanism 80 together according to the driving mode, and may configure various driving modes according to the load. Is smaller than the normal load, the compressor 10, the booster compressor 90 and the second booster expansion mechanism 80 is operated in the partial load mode, and if the load is a normal load, the compressor 10 and the booster compressor 90 and The second booster expansion mechanism 80 is operated in the normal load mode, and when the load is greater than the normal load, the compressor 10, the booster compressor 90, and the second booster expansion mechanism 80 are operated in the multi operation mode, In the case of a low temperature load, the compressor 10, the booster compressor 90, and the second booster expansion mechanism 80 may be operated in the gas injection mode.

In the heat pump according to the present embodiment, the compressor 10 is a variable-capacity compressor, the booster compressor 90 is a constant speed compressor, and the booster compressor 90 is more compact than the compressor 10 in order to efficiently cope with various loads. It is preferable that the capacity is formed small.

The controller 120 turns off the compressor 10 in the partial load mode, drives the booster compressor 90, and seals the second booster expansion mechanism 80. In addition, the controller 120 may fully open the first booster expansion mechanism 62 and adjust the opening degree of the expansion mechanism 16 to a set opening degree so that the expansion mechanism 16 expands the refrigerant.

In this case, the controller 120 may control the opening degree of the expansion mechanism 16 such that the suction superheat degree of the booster compressor 90 reaches the set superheat degree.

2 and 8, the refrigerant of the compressor suction pipe 19 is not introduced into the compressor 10, and the booster suction pipe 96 and the booster compressor suction pipe 92 are sequentially turned on. After passing through, it is sucked into the booster compressor 90 and compressed, and then passes through the booster compressor discharge pipe 94 and the compressor discharge pipe 13 in order to flow to the first heat exchanger 14.

The refrigerant flowing into the first heat exchanger 14 condenses in the first heat exchanger 14 and heats the water passing through the first heat exchanger 14, and then the first booster expansion mechanism 62 and the gas-liquid separator ( 70, which in turn may be expanded in the expansion mechanism 16 and then flow to the second heat exchanger 18.

The refrigerant flowing into the second heat exchanger 18 may be evaporated by the outdoor air blown by the outdoor fan 22, and then recovered into the compressor suction pipe 19.

That is, the heat pump is compressed, condensed, expanded, and evaporated while the refrigerant circulates through the booster compressor 90, the first heat exchanger 14, the expansion mechanism 16, and the second heat exchanger 18, and the compressor 10. In the case of driving, it is possible to cope with the partial load with less power consumption.

The controller 120 drives the compressor 10 in the normal load mode, stops the booster compressor 90, and closes the second booster expansion mechanism 80. In addition, the controller 120 may fully open the first booster expansion mechanism 62 and adjust the opening degree of the expansion mechanism 16 to a set opening degree so that the expansion mechanism 16 expands the refrigerant.

In this case, the controller 120 may control the opening degree of the expansion mechanism 16 such that the suction superheat degree of the compressor 10 reaches the set superheat degree.

2 and 9, the refrigerant in the compressor suction pipe 19 is not introduced into the booster compressor 90, but is sucked into the compressor 10 and compressed, and then the compressor discharge pipe ( 13) in order to flow to the first heat exchanger (14).

That is, the heat pump is compressed, condensed, expanded, and evaporated while the refrigerant circulates through the compressor 10, the first heat exchanger 14, the expansion mechanism 16, and the second heat exchanger 18, and the booster compressor 90. In the case of driving of larger general loads can be coped with.

The controller 120 drives the compressor 10 and the booster compressor 90 in the multi-operation mode, and seals the second booster expansion mechanism 80. In addition, the controller 120 may fully open the first booster expansion mechanism 62 and adjust the opening degree of the expansion mechanism 16 to a set opening degree so that the expansion mechanism 16 expands the refrigerant.

As shown in FIGS. 2 and 10, the refrigerant in the compressor suction pipe 19 is partially sucked into the compressor 10, compressed, and then discharged into the compressor discharge pipe 13, and the rest is booster suction. After passing through the pipe 96 and the booster compressor suction pipe 92 in sequence, the suction is compressed into the booster compressor 90 and then compressed into the compressor discharge pipe 13 to be combined with the refrigerant discharged from the compressor 10.

The refrigerant discharged into the compressor discharge pipe 13 flows to the first heat exchanger 14 to condense in the first heat exchanger 14 and heat the water passing through the first heat exchanger 14, and then the first booster. Passes through the expansion mechanism 62 and the gas-liquid separator 70 in order, and may be expanded in the expansion mechanism 16 and then flow to the second heat exchanger 18.

That is, the heat pump is compressed, condensed, expanded, and evaporated while the refrigerant circulates through the compressor 10, the booster compressor 90, the first heat exchanger 14, the expansion mechanism 16, and the second heat exchanger 18. In the case of the single drive of the booster compressor 90 and the single drive of the compressor 10, it is possible to cope with a larger heavy load.

The controller 120 may drive the compressor 10 and the booster compressor 90 in the gas injection mode, and open the second booster expansion mechanism 80. In addition, the controller 120 may open the first booster expansion mechanism 62 and adjust the opening degree of the expansion mechanism 16 to a set opening degree so that the expansion mechanism 16 expands the refrigerant.

At this time, the control unit 120 is a first pressure such that the pressure of the refrigerant sucked into the booster compressor 90 is lower than the evaporation pressure of the second heat exchanger 18, and the intermediate pressure is higher than the condensation pressure of the first heat exchanger 14. The opening degree of the booster expansion mechanism 80 and the opening degree of the second booster expansion mechanism 80 can be controlled, and the opening degree of the expansion mechanism 16 can be controlled so that the suction superheat degree of the compressor 10 reaches the set superheat degree.

As shown in FIGS. 2 and 11, the refrigerant in the compressor suction pipe 19 is sucked into the compressor 10, compressed, discharged into the compressor discharge pipe 13, and then the first heat exchanger ( 14 to the water flowing through the first heat exchanger 14 while condensing in the first heat exchanger 14, and then expanded in the first booster expansion mechanism 62 and then introduced into the gas-liquid separator 70 Can be. The refrigerant introduced into the gas-liquid separator 70 separates the gaseous refrigerant and the liquid refrigerant, and the gaseous refrigerant discharges the gaseous refrigerant discharge pipe 76, and the liquid refrigerant expands the expansion mechanism 16 through the expansion mechanism inlet pipe 72. Can be expanded to expand.

The refrigerant expanded in the expansion mechanism (16) flows to the second heat exchanger (18), is evaporated, and then recovered to the compressor suction pipe (19), compressed in the compressor (10) and then discharged to the compressor discharge pipe (13). Can be.

Meanwhile, the refrigerant discharged into the gaseous phase refrigerant discharge pipe 76 is expanded in the second booster expansion mechanism 80 and then flows into the booster compressor suction pipe 92, and is then compressed in the booster compressor 90. The refrigerant compressed by the booster compressor 90 is discharged into the booster compressor discharge pipe 94 and then flows into the press discharge pipe 13 to be mixed with the refrigerant discharged from the compressor 10.

That is, the heat pump is compressed, condensed while the refrigerant circulates the compressor 10, the first heat exchanger 14 and the first booster expansion mechanism 62, the expansion mechanism 16 and the second heat exchanger 18, Expansion, expansion, evaporation, gaseous refrigerant in the condensed refrigerant in the first heat exchanger 14 is expanded and then gas injected into the booster compressor 90, the heat pump is a booster compressor 90 and the compressor (10) without gas injection ), The compression work is reduced with higher efficiency. In particular, the low temperature heating ability of the outdoor low temperature can be improved.

12 is a configuration diagram after a booster module is installed in a refrigeration cycle unit of another embodiment of a heat pump according to the present invention, and FIG. 13 is a schematic configuration diagram showing a refrigerant flow in a normal load mode of another embodiment of the heat pump according to the present invention; 14 is a schematic block diagram showing a refrigerant flow in the gas injection mode of another embodiment of the heat pump according to the present invention.

In the heat pump according to the present embodiment, the booster suction pipe 96 and the check valve 96 'of one embodiment of the present invention are not installed, and other configurations may be the same as or similar to the embodiment of the present invention.

As shown in FIG. 12, the heat pump according to the present embodiment has a general load mode in which the compressor 10 is driven, the booster compressor 90 is not driven, and the second booster expansion mechanism 80 does not pass the gaseous refrigerant. 14, the compressor 10 and the booster compressor 90 may be driven, and the second booster expansion mechanism 80 may have a gas injection mode through which the gaseous refrigerant passes.

That is, when the low temperature load is detected by the load detection sensor 110, the compressor 10 and the booster compressor 90 are driven and the second booster expansion mechanism 80 is controlled to pass the gaseous refrigerant, so that the compressor 10 The refrigerant evaporated in the evaporator 18 may be compressed, and the booster compressor 90 may compress the gaseous refrigerant separated in the gas-liquid separator 70.

On the other hand, when the low temperature load is not detected by the load sensor 110, the compressor 10 is driven, the booster compressor 90 is not driven, and the second booster expansion mechanism 80 is controlled not to pass the gaseous refrigerant. The compressor 10 may compress the refrigerant evaporated from the evaporator 10.

15 is a configuration diagram before the booster module is installed in the refrigeration cycle unit of another embodiment of the heat pump according to the present invention, Figure 16 is a configuration diagram after the booster module is installed in the refrigeration cycle unit of another embodiment of the heat pump according to the present invention to be.

The heat pump according to the present embodiment is for heating purposes only, and does not include the cooling / heating switching valve 12 of one embodiment of the present invention, and other configurations may be the same as or similar to the embodiment of the present invention.

In the refrigeration cycle unit 1, the compressor 10 is connected to the first heat exchanger 14 and the compressor discharge pipe 11, and the first heat exchanger 14 is expanded to the expansion mechanism 16 and the first heat exchanger-expansion. It is connected to the instrument connecting pipe 15, the expansion mechanism 16 is connected to the second heat exchanger 18 and the expansion mechanism-second heat exchanger connecting pipe 17, the second heat exchanger 18 is a compressor ( 10) and the compressor suction pipe 20 '.

In the heat pump according to the present embodiment, when the booster module 2 is installed, each of the compressor discharge pipe 11 and the first heat exchanger-expansion mechanism connecting pipe 15 is separated, and the booster module 2 is separated. It may be connected to the compressor discharge pipe (11A) (11B), it may be connected to the separated first heat exchanger-expansion mechanism connecting pipe (15A) 15B.

The booster module 2 includes a first booster compressor discharge pipe connecting one 11A and the other 11B of the compressor discharge pipes 11A and 11B from which the booster

compressor discharge pipes

94 and 95 are separated. 94 and a second booster compressor discharge pipe 95 for guiding the refrigerant discharged from the booster compressor 90 to the first booster compressor discharge pipe 94.

That is, the compressor 10 and the first heat exchanger 14 are connected to the compressor discharge pipe 11 as shown in FIG. 14 before the booster module 2 is installed, and after the booster module 2 is installed. As shown in FIG. 15, one of 11A of the compressor discharge pipe 11, the first booster compressor discharge pipe 94, and the other 11B of the compressor discharge pipe 11 may be connected.

One end of the booster suction pipe 96 may be connected to the compressor suction pipe 20 ′ and the other end may be connected to the booster compressor suction pipe 92.

Claims

A compressor in which the refrigerant is compressed and a first heat exchanger in which the refrigerant compressed in the compressor is condensed

An expansion mechanism to expand the refrigerant condensed in the first heat exchanger;

A refrigeration cycle unit having a second heat exchanger for evaporating the refrigerant expanded therein;

Is connected to the refrigeration cycle unit and flows from the first heat exchanger to an expansion mechanism

After separating and compressing the gaseous refrigerant from the refrigerant to be used between the compressor and the first heat exchanger

The compressor after flowing to or compressing the refrigerant evaporated in the second heat exchanger.

And a booster module for flowing between the first heat exchanger.
The method of claim 1,

The booster module expands the refrigerant flowing in the first heat exchanger.

With booster inflator,

Separation of the liquid refrigerant and the gaseous refrigerant from the refrigerant expanded by the first booster expansion mechanism

With gas-liquid separator made,

Second booster expansion mechanism for expanding the gaseous refrigerant separated by the gas-liquid separator

Wow,

A booster compressor for compressing the refrigerant expanded in the second booster expansion mechanism;

With heat pump.
The method of claim 2,

The booster module is a refrigerant evaporated from the second heat exchanger is the booster pressure

And a booster suction pipe for guiding suction to the accumulator.
The method of claim 3, wherein

The booster module connects the first booster expansion mechanism and the gas-liquid separator.

Gas-liquid separator suction piping,

The gaseous refrigerant separated in the gas-liquid separator does not reach the second booster expansion mechanism.

Internal gaseous refrigerant discharge pipe,

The refrigerant expanded in the second booster expansion mechanism is sucked into the booster compressor.

The booster compressor suction pipe,

The refrigerant discharged from the booster compressor is between the compressor and the first heat exchanger.

Further comprising a booster compressor discharge pipe is guided to,

The booster suction pipe is between the second heat exchanger and the compressor and the booster

Heat pump connecting compressor suction line.
The method of claim 4, wherein

The booster module is installed in the booster suction pipe and the booster compressor

Prevents the refrigerant in the suction pipe from being sucked into the compressor through the booster suction pipe.

The heat pump further comprises a check valve.
The method of claim 4, wherein

The first booster expansion mechanism includes the first heat exchanger and the first booster expansion mechanism.

Heat pump connected to suction line.
The method of claim 4, wherein

The gas-liquid separator is connected to the expansion mechanism and the gas-liquid separator outlet pipe.

Pump.
The method of claim 3, wherein

The compressor is a variable displacement compressor, the booster compressor is a constant speed compressor

Heat pump.
The method of claim 3, wherein

Said booster compressor having a smaller capacity than said compressor.
The method of claim 3, wherein

The heat pump may include the compressor and the booster compressor according to an operation mode.

A heat pump comprising a control unit for controlling the stuffer expansion mechanism.
The method of claim 10,

The control unit drives the compressor in the normal load mode, the booster pressure

A heat pump for stopping the accumulator and sealing the second booster expansion mechanism.
The method of claim 10,

The control unit turns off the compressor in the partial load mode, the booster pressure

A heat pump driving the accumulator and sealing the second booster expansion mechanism.
The method of claim 10,

The control unit may drive the compressor and the booster compressor in a multi operation mode.

And sealing the second booster expansion mechanism.
The method of claim 10,

The control unit may drive the compressor and the booster compressor in the gas injection mode.

And open the second booster expansion mechanism.
The method of claim 1,

The first heat exchanger is a water refrigerant heat exchanger for heat exchange between the refrigerant and water, and indoors

Connected to a water circulation passage and a heating unit for heating the

Heat pump.
A compressor in which the refrigerant is compressed and a first heat exchanger in which the refrigerant compressed in the compressor is condensed

An expansion mechanism to expand the refrigerant condensed in the first heat exchanger;

A refrigeration cycle unit having a second heat exchanger for evaporating the refrigerant expanded therein;

A booster module selectively mounted to the refrigeration cycle unit,

The booster module expands the refrigerant flowing in the first heat exchanger.

With booster inflator,

Separation of the liquid refrigerant and the gaseous refrigerant from the refrigerant expanded by the first booster expansion mechanism

With gas-liquid separator made,

Second booster expansion mechanism for expanding the gaseous refrigerant separated by the gas-liquid separator

Wow,

A booster compressor for compressing the refrigerant expanded in the second booster expansion mechanism;

And a heat pump selectively operated in response to the indoor load.
The method of claim 16,

The booster module connects the first booster expansion mechanism and the gas-liquid separator.

Gas-liquid separator suction piping,

The gaseous refrigerant separated in the gas-liquid separator does not reach the second booster expansion mechanism.

Internal gaseous refrigerant discharge pipe,

The refrigerant expanded in the second booster expansion mechanism is sucked into the booster compressor.

The booster compressor suction pipe,

The refrigerant discharged from the booster compressor is between the compressor and the first heat exchanger.

The heat pump further comprises a booster compressor discharge pipe is guided to.
The method of claim 17,

The first booster expansion mechanism includes the first heat exchanger and the first booster expansion mechanism.

Heat pump connected to suction line.
The method of claim 18,

The gas-liquid separator is connected to the expansion mechanism and the gas-liquid separator outlet pipe.

Pump.
The method of claim 17,

The compressor is a variable displacement compressor,

The booster compressor is a heat pump which is a constant speed compressor having a smaller capacity than the compressor.

F.