Air conditioning system adopting three-pipe technology

Abstract

The invention relates to an air conditioning system of a three-pipe technology, which comprises a compressor comprising a suction inlet and an output port, the suction inlet sucks a low-temperature and low-pressure refrigerant, and the output port outputs a high-temperature and high-pressure refrigerant; the condenser is used for condensing the high-temperature and high-pressure refrigerant discharged by the compressor into medium-temperature and medium-pressure refrigerant and storing the medium-temperature and medium-pressure refrigerant in the liquid storage device; a heat dissipation tail end and a cold dissipation tail end; the heating loop comprises a high-pressure pipeline connected between the compressor and the heat dissipation tail end and a first medium-pressure pipeline connected between the liquid storage device and the heat dissipation tail end, a high-temperature and high-pressure refrigerant is conveyed to the heat dissipation tail end along the high-pressure pipeline, and the medium-temperature and medium-pressure refrigerant after heat exchange returns to the liquid storage device along the medium-pressure pipeline; the refrigerating circuit comprises a second medium-pressure pipeline connected between the liquid storage device and the cold dissipation tail end and a low-pressure pipeline connected between the cold dissipation tail end and the suction inlet, and a throttling and pressure reducing valve used for reducing pressure is installed at the tail end of the second medium-pressure pipeline. The air conditioner has the advantages of being easy to operate, low in energy consumption and capable of achieving refrigeration and heating at the same time.

Description

Technical Field

[0001] This application relates to the field of air conditioning heat exchange technology, and in particular to an air conditioning system using a three-pipe technology. Background Technology

[0002] Currently, for households with multiple heat exchange terminals, a central air conditioning system is often used to drive multiple household heat exchange terminals for heat exchange; this is known as a multi-split air conditioner. Ordinary multi-split air conditioners use ammonia or Freon as refrigerants. These air conditioners only have two power supply modes: cooling or heating. However, in some special situations or based on specific customer requirements, it is necessary to cool and heat different rooms simultaneously, and in such cases, ordinary multi-split air conditioners cannot meet the needs.

[0003] In recent years, with the continuous development of heating technology, four-pipe water-cooled central air conditioning systems have emerged on the market, capable of providing cooling and heating in different rooms. Water is used as the heat exchange medium in the indoor pipes. Its working principle involves first exchanging heat between the outdoor heat exchanger and the water in the indoor pipes, and then a secondary heat exchange between the water in the indoor pipes and the indoor heat exchanger. Independent cooling or heating can be achieved by controlling the heat exchange valves.

[0004] Although water-cooled central air conditioning can meet the cooling and heating needs of different rooms, this method requires secondary heat exchange, is relatively complex to operate, and has high energy consumption. Summary of the Invention

[0005] In order to provide a multi-split air conditioner that is simple to operate, has low energy consumption, and can simultaneously cool or heat, this application provides an air conditioning system with three-pipe technology.

[0006] The air conditioning system using a three-pipe technology provided in this application adopts the following technical solution: A three-pipe air conditioning system, comprising: The compressor includes an inlet and an outlet, wherein the inlet draws in a low-temperature, low-pressure refrigerant and the outlet outputs a high-temperature, high-pressure refrigerant; A condenser is used to condense the high-temperature, high-pressure refrigerant discharged from the compressor into a medium-temperature, medium-pressure liquid and store it in a liquid receiver. Heat dissipation terminals and cooling terminals; The heating circuit includes a high-pressure pipeline connected between the compressor and the heat dissipation terminal, and a first medium-pressure pipeline connected between the liquid receiver and the heat dissipation terminal. The high-temperature and high-pressure refrigerant is transported to the heat dissipation terminal for heat exchange along the high-pressure pipeline, and the medium-temperature and medium-pressure refrigerant after heat exchange returns to the liquid receiver along the first medium-pressure pipeline. The refrigeration circuit includes a second medium-pressure pipeline connected between the liquid receiver and the cooling terminal and a low-pressure pipeline connected between the cooling terminal and the suction port. The end of the second medium-pressure pipeline is equipped with a throttling and pressure-reducing valve for reducing the pressure of the medium-temperature and medium-pressure refrigerant to a low-temperature and low-pressure state.

[0007] By adopting the above technical solution, during heating, the high-temperature, high-pressure refrigerant compressed by the compressor is directly transported to the heat dissipation terminal through the high-pressure pipeline. The heat dissipation terminal releases heat and exchanges heat with the cold air outside, causing the high-temperature, high-pressure refrigerant to cool down into a medium-temperature, medium-pressure liquid refrigerant, which is then transported back to the receiver for use during cooling. During cooling, the compressor discharges the high-temperature, high-pressure refrigerant, which is condensed and cooled into a medium-temperature, medium-pressure liquid by the condenser and transported to the receiver. The receiver then transports the medium-temperature, medium-pressure refrigerant through a second medium-pressure pipeline, and after passing through a throttling and pressure-reducing valve, it is depressurized to a low-temperature, low-pressure state and directly transported to the cooling terminal. The cooling terminal releases cold energy to the outside and absorbs heat from the outside, causing the low-temperature, low-pressure refrigerant to heat up to a higher-temperature, low-pressure gaseous state, which is then returned to the compressor's suction port for secondary utilization, realizing a self-heating cycle and achieving greater energy savings. Since each cooling terminal and heat dissipation terminal forms a separate circulation system with the compressor and receiver, simultaneous cooling and heating of different rooms can be achieved through the valves of each terminal. Furthermore, compared to traditional water-cooled central air conditioning systems, the refrigerant in this application enters the room directly for cooling or heating without the need for secondary exchange via water. This saves on circulation power, simplifies the structure, eliminates the need for power equipment, and results in lower energy consumption.

[0008] Optionally, the refrigerant is carbon dioxide.

[0009] By adopting the above technical solution, carbon dioxide is used as the operating medium, which can reduce ozone layer depletion compared to media such as Freon, and is in line with the national energy conservation and low-carbon environmental protection concept.

[0010] Optionally, the refrigerant includes four forms: a high-temperature, high-pressure gaseous state for heating; a medium-temperature, medium-pressure liquid state for flowing in the first and second medium-pressure pipelines; a low-temperature, low-pressure gaseous state for cooling; and a low-temperature, low-pressure gaseous state after heat exchange with the cooling terminal.

[0011] By adopting the above technical solution and switching between four modes, it is easy to adjust the cooling and heating.

[0012] Optionally, the throttling and pressure-reducing valve is an electronic expansion valve.

[0013] By adopting the above technical solution, temperature and pressure can be rapidly adjusted by regulating the opening of the electronic expansion valve.

[0014] Optionally, the heating circuit also includes a heat collector for heat balance, wherein the input end and output end of the heat collector are respectively connected to the first medium-pressure pipeline and the high-pressure pipeline, for supplementing heat supply when the compressor is insufficient to generate heat.

[0015] By adopting the above technical solution, when the compressor does not generate enough heat, heat is exchanged with the outside through the heat collector to heat the low-temperature, low-pressure carbon dioxide into high-temperature, high-pressure heat and supply it to each heat dissipation terminal, thereby regulating the heat supply balance of the air conditioning system.

[0016] Optionally, the solar collector includes a heat-absorbing plate for heat absorption and a heat conduction pipe for heat conduction. The first medium-pressure pipe and the high-pressure pipe are respectively connected to the two ends of the heat conduction pipe. A throttling and pressure-reducing valve is installed at the end of the first medium-pressure pipe connected to the solar collector. The throttling and pressure-reducing valve is used to reduce the pressure of the medium-temperature and medium-pressure liquid refrigerant to a low-temperature and low-pressure liquid state.

[0017] By adopting the above technical solution, the medium-temperature and medium-pressure carbon dioxide in the first medium-pressure pipeline is depressurized by the electronic expansion valve and becomes low-temperature and low-pressure carbon dioxide. The low-temperature and low-pressure carbon dioxide flows in the heat conduction pipeline. During the flow, the heat absorption plate transfers the absorbed heat to the heat conduction pipeline to heat the low-temperature and low-pressure carbon dioxide into high-temperature and high-pressure carbon dioxide, so as to deliver it to the heat dissipation terminal for heat exchange.

[0018] Optionally, the heat-absorbing plate is used to absorb heat from sunlight when there is ample sunlight and / or to absorb temperature from the outside air when the outdoor temperature is higher than the temperature inside the first medium-pressure pipe on a cloudy day.

[0019] By adopting the above technical solution, when there is sufficient sunlight, the heat absorber absorbs sunlight and stores it in the plate, causing the heat absorber to heat up; when it is cloudy outdoors in winter, but the outdoor temperature is higher than the temperature of carbon dioxide in the heat conduction pipe, the heat absorbs the outside temperature through radiation and achieves heat exchange through the temperature difference, making the heat exchange scenarios more extensive.

[0020] Optionally, the heat-absorbing plate is provided with two layers, and the heat conduction pipe is located between the two heat-absorbing plates.

[0021] By adopting the above technical solution, the heat absorption function of the heat absorption plate is enhanced.

[0022] Optionally, the heat conduction conduit is a serpentine tube.

[0023] By adopting the above technical solution, carbon dioxide travels for a longer time in the heat conduction pipe, resulting in a better heating effect on the carbon dioxide.

[0024] Optionally, the heat-absorbing plate is a solar photovoltaic panel, and a storage battery is connected to the end of the solar photovoltaic panel, which is connected to the compressor.

[0025] By adopting the above technical solutions, the solar collector can not only supply power to the system and save energy, but also provide heat to the heat dissipation terminal when the compressor is insufficient, thus making the solar collector more functional.

[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. This application directly introduces refrigerant into the room for cooling or heating without the need for secondary exchange, making operation simpler and saving energy. Since each heat dissipation terminal and cooling terminal forms a separate circuit with the compressor and receiver, the flow of refrigerant can be controlled by controlling each heat dissipation terminal or its valve. This allows for heating of a single heat dissipation terminal or cooling of a cooling terminal, and simultaneous cooling or heating in different rooms. 2. By using carbon dioxide as the operating medium, damage to the ozone layer is reduced, making it more low-carbon and environmentally friendly; 3. By installing a heat collector in the heating circuit, when the compressor's heating supply is insufficient, the heat dissipation terminal can be supplemented in a timely manner to regulate the system's heating balance. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the heating circuit of this application.

[0028] Figure 2 This is a schematic diagram of the cooling circuit of this application.

[0029] Figure 3 This is an overall schematic diagram of the air conditioning system of this application.

[0030] Explanation of reference numerals in the attached diagram: 1. Compressor; 101. Inlet; 102. Outlet; 2. Condenser; 3. Receiver; 4. Heat dissipation terminal; 5. Cooling terminal; 6. High-pressure pipeline; 7. First medium-pressure pipeline; 8. Second medium-pressure pipeline; 9. Low-pressure pipeline; 10. Solar collector; 11. Throttling and pressure reducing valve. Detailed Implementation

[0031] The following is in conjunction with the appendix Figure 1-3 This application will be described in further detail.

[0032] This application discloses an air conditioning system using a three-pipe technology. (Refer to...) Figure 1 and Figure 2 The three-pipe air conditioning system includes a compressor 1, a condenser 2, a liquid receiver 3, a heat dissipation terminal 4 and a cooling terminal 5 installed in the user's room, a heating circuit for heating the heat dissipation terminal 4, and a refrigeration circuit for cooling the cooling terminal 5.

[0033] The compressor 1 includes a suction port 101 and an output port 102. The suction port 101 is used to draw in low-temperature and low-pressure refrigerant. After the compressor 1 compresses and heats up the refrigerant, it is compressed into high-temperature and high-pressure refrigerant and discharged from the output port 102.

[0034] Compressor 1 is connected to condenser 2 via a delivery pipe. Condenser 2 is used to condense the high-temperature, high-pressure refrigerant discharged from compressor 1 into medium-temperature, medium-pressure refrigerant. Condenser 2 is connected to receiver 3 to deliver the condensed medium-temperature, medium-pressure refrigerant to receiver 3 for storage.

[0035] The heating circuit includes a high-pressure pipeline 6 connecting the compressor 1 and the heat dissipation terminal 4, and a first medium-pressure pipeline 7 connecting the liquid receiver 3 and the heat dissipation terminal 4. During heating, the high-temperature, high-pressure refrigerant compressed by the compressor 1 is discharged from the outlet 102 and directly transported to the heat dissipation terminal 4 along the high-pressure pipeline 6. The heat dissipation terminal 4 releases heat and exchanges heat with the cold air outside, causing the high-temperature, high-pressure refrigerant to cool down into a medium-temperature, medium-pressure refrigerant. The medium-temperature, medium-pressure refrigerant after heat exchange returns to the liquid receiver 3 along the first medium-pressure pipeline 7 for use during cooling.

[0036] The refrigeration circuit includes a second medium-pressure pipeline 8 connecting the liquid receiver 3 and the cooling terminal 5, and a low-pressure pipeline 9 connecting the cooling terminal 5 and the suction port 101. The end of the second medium-pressure pipeline 8 is equipped with a throttling and pressure-reducing valve 11 to reduce the pressure of the medium-temperature, medium-pressure refrigerant to a low-temperature, low-pressure state. During refrigeration, the high-temperature, high-pressure refrigerant, compressed by the compressor 1, is fed into the condenser 2 through the delivery pipeline. After condensation and cooling in the condenser 2, it becomes medium-temperature, medium-pressure and is then delivered to the liquid receiver 3. The liquid receiver 3 delivers the medium-temperature, medium-pressure refrigerant through the second medium-pressure pipeline 8, and after being reduced to a low-temperature, low-pressure state by the throttling and pressure-reducing valve 11, it is directly delivered to the cooling terminal 5. The cooling terminal 5 releases cold energy to the outside and absorbs heat from the outside, causing the low-temperature, low-pressure refrigerant to heat up to a higher temperature than its input temperature and low-pressure state. This refrigerant then returns to the suction port 101 of the compressor 1 for secondary utilization, achieving a self-heating cycle and increasing energy efficiency. Preferably, the throttling and pressure reducing valve 11 is an electronic expansion valve, which can achieve rapid adjustment of temperature and pressure by adjusting the opening of the electronic expansion valve.

[0037] Since each cooling terminal 5 and heat dissipation terminal 4 is a separate circulation system with the compressor 1 and the liquid receiver 3, when different rooms need to be cooled and heated at the same time, it can be achieved through the valves of the cooling terminal 5 and the heat dissipation terminal 4 respectively.

[0038] Preferably, carbon dioxide can be used as the refrigerant in this application. Carbon dioxide is an emerging refrigerant, and compared with media such as Freon, it can reduce ozone layer depletion, which is in line with the national energy conservation and low-carbon environmental protection concept.

[0039] Since carbon dioxide is used as the operating medium, it exists in four states: a high-temperature, high-pressure gaseous state for heating flowing in the high-pressure pipeline 6; a medium-temperature, medium-pressure liquid state flowing in the first and second medium-pressure pipelines 7 and 8; a low-temperature, low-pressure gaseous state for cooling introduced into the cooling terminal 5; and a low-temperature, low-pressure gaseous state with a higher temperature than the input temperature after heat exchange with the cooling terminal 5. Switching between these four states facilitates the regulation of cooling and heating.

[0040] Reference Figure 3 In this application, the heat dissipation terminal 4 includes, but is not limited to, residential underfloor heating, radiators, fan coil units, etc.; the cooling terminal 5 includes, but is not limited to, residential refrigerators, cold storage, fan coil units, etc. In actual use, when high-temperature, high-pressure carbon dioxide is introduced into the fan coil unit, it is considered as the heat dissipation terminal 4; when low-temperature, low-pressure gaseous carbon dioxide is introduced into the fan coil unit, it is considered as the cooling terminal 5. Therefore, in the design of the air conditioning system, the fan coil unit is connected to both a high-pressure pipeline 6 for use during heating and a low-pressure pipeline 9 for returning the low-temperature, low-pressure gaseous carbon dioxide generated during heat exchange during cooling to the suction port 101 of the compressor 1. The distinction made in this application regarding the fan coil unit is only for the convenience of explaining the refrigeration circuit and the heating circuit.

[0041] Furthermore, in actual use of the air conditioning system of this application, the pipelines connecting the liquid receiver 3 and the heat dissipation terminal 4, the cooling terminal 5, and the collector 10 for transporting medium-temperature and medium-pressure liquid carbon dioxide are not distinguished as a first medium-pressure pipeline 7 and a second medium-pressure pipeline 8. Adjustment is achieved solely through the control of the corresponding pipeline valves. In this application, this distinction is merely for the convenience of explaining and understanding the heating and cooling circuits.

[0042] Reference Figure 1 Furthermore, the heating circuit also includes a heat collector 10 for heat supply balancing. The input and output ends of the heat collector 10 are connected to the first medium-pressure pipeline 7 and the high-pressure pipeline 6, respectively, for supplementing heat supply when the compressor 1 is insufficient in heat production.

[0043] Specifically, the solar collector 10 includes a heat-absorbing plate (not shown in the figure) for heat absorption and a heat conduction pipe (not shown in the figure) for heat conduction. A first medium-pressure pipe 7 and the high-pressure pipe 6 are respectively connected to both ends of the heat conduction pipe. A throttling and pressure-reducing valve 11 is also installed at the end of the first medium-pressure pipe 7 connected to the solar collector 10. The throttling and pressure-reducing valve 11 is used to reduce the pressure of the medium-temperature, medium-pressure liquid refrigerant to a low-temperature, low-pressure liquid state. The throttling and pressure-reducing valve 11 also uses an electronic expansion valve.

[0044] It should be noted that by controlling the opening of the electronic expansion valve, the medium-temperature, medium-pressure liquid carbon dioxide can be depressurized into a low-temperature, low-pressure gaseous state or a low-temperature, low-pressure liquid state. The electronic expansion valve connected to the solar collector 10 and the electronic expansion valve connected to the cooling terminal 5 have different openings.

[0045] When compressor 1 provides insufficient heat, medium-temperature, medium-pressure carbon dioxide, after heat exchange at the heat dissipation terminal 4 and stored in the liquid receiver 3, is transported to the solar collector 10. After being depressurized by the electronic expansion valve, it becomes low-temperature, low-pressure liquid carbon dioxide. This low-temperature, low-pressure carbon dioxide flows through the heat conduction pipes. During this flow, the heat absorption plate transfers the absorbed heat to the heat conduction pipes, heating the low-temperature, low-pressure carbon dioxide into a high-temperature, high-pressure gaseous state, which is then transported to the heat dissipation terminal 4 for heat exchange. The medium-temperature, medium-pressure liquid carbon dioxide after heat exchange at the heat dissipation terminal 4 returns to the liquid receiver 2, thus achieving a balanced heat collection cycle and saving energy.

[0046] Preferably, the heat absorption plate has two layers, with the heat conduction pipe located between the two heat absorption plates. This results in better heat absorption by the heat conduction pipe and higher heating efficiency for the carbon dioxide within it.

[0047] Even better, the heat conduction pipe is a serpentine pipe, which allows the carbon dioxide to travel for a longer time inside the heat conduction pipe, resulting in a better heating effect on the carbon dioxide.

[0048] The heat absorber plate is used to absorb heat from sunlight when there is ample sunlight and / or absorb heat from the outside air when the outdoor temperature is higher than the temperature inside the first medium-pressure pipe on cloudy days. Specifically, when there is ample sunlight, the heat absorber plate absorbs sunlight and stores it in the plate, causing the heat absorber plate to heat up; when it is cloudy in winter and the outdoor temperature is higher than the temperature of carbon dioxide inside the heat conduction pipe, it absorbs the outside temperature through radiation and achieves heat exchange through the temperature difference, thus broadening the range of heat exchange scenarios.

[0049] Furthermore, the heat absorber in this application is a solar photovoltaic panel. A battery (not shown in the figure) is connected to the end of the solar photovoltaic panel, and the battery is connected to the compressor 1 and the condenser 2 to provide energy for the operation of the compressor 1 and the condenser 2, thus saving energy consumption.

[0050] The implementation principle of a three-pipe air conditioning system according to an embodiment of this application is as follows: When heating, the high-temperature and high-pressure gaseous carbon dioxide generated by the compressor 1 is transported to the heat dissipation terminal 4 for heat exchange. After the heat exchange and cooling, the medium-temperature and medium-pressure liquid carbon dioxide is transported back to the liquid receiver 3 along the first medium-pressure pipeline 7.

[0051] During cooling, the medium-temperature, medium-pressure liquid carbon dioxide in the receiver 2 is transported along the second medium-pressure pipeline 8 and depressurized through the throttling and pressure-reducing valve 11 to become a low-temperature, low-pressure gaseous state. After exchanging heat with the outside environment, it becomes a higher-temperature, low-pressure gaseous state and returns to the suction port 101 of the compressor 1. The heating circuit realizes the circulation of medium-temperature, medium-pressure liquid carbon dioxide, which is convenient for use in the cooling cycle; the cooling circuit realizes the circulation of low-temperature, low-pressure gaseous carbon dioxide, which is convenient for use in the heating cycle. When different rooms are simultaneously cooling and heating, a self-circulating and mutually reinforcing effect is achieved, resulting in better energy-saving performance.

[0052] During winter when heating is required, if the compressor 1's capacity is insufficient, the collector 10 absorbs heat from sunlight and the outside environment to supplement the heat dissipation terminal 4. The medium-temperature, medium-pressure liquid carbon dioxide after heat exchange at the heat dissipation terminal 4 returns to the liquid receiver 3, realizing a separate energy supply cycle for the collector 10. This plays a regulatory role in the entire air conditioning system, making the system's operation more stable and efficient.

[0053] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An air conditioning system using three-pipe technology, characterized in that: include: The compressor (1) includes an inlet (101) and an outlet (102), wherein the inlet (101) draws in a low-temperature, low-pressure refrigerant and the outlet (102) outputs a high-temperature, high-pressure refrigerant; The condenser (2) is used to condense the high-temperature and high-pressure refrigerant discharged by the compressor (1) into a medium-temperature and medium-pressure liquid and store it in the liquid receiver (3); Heat dissipation terminal (4) and cooling terminal (5); The heating circuit includes a high-pressure pipeline (6) connecting the compressor (1) and the heat dissipation terminal (4) and a first medium-pressure pipeline (7) connecting the liquid receiver (3) and the heat dissipation terminal (4). The high-temperature and high-pressure refrigerant is transported to the heat dissipation terminal (4) through the high-pressure pipeline (6) for heat exchange. The medium-temperature and medium-pressure refrigerant after heat exchange returns to the liquid receiver (3) through the first medium-pressure pipeline (7). The refrigeration circuit includes a second medium-pressure pipeline (8) connected between the liquid receiver (3) and the cooling terminal (5) and a low-pressure pipeline (9) connected between the cooling terminal (5) and the suction port (101). The end of the second medium-pressure pipeline (8) is equipped with a throttling and pressure-reducing valve (11) for reducing the pressure of the medium-temperature and medium-pressure refrigerant to a low-temperature and low-pressure state.

2. The air conditioning system using the three-pipe technology according to claim 1, characterized in that: The refrigerant is carbon dioxide.

3. The air conditioning system using the three-pipe technology according to claim 2, characterized in that: The refrigerant includes four forms: high-temperature and high-pressure gaseous state for heating, medium-temperature and medium-pressure liquid state for flowing in the first medium-pressure pipeline (7) and the second medium-pressure pipeline (8), low-temperature and low-pressure gaseous state for cooling, and low-temperature and low-pressure gaseous state after heat exchange with the cooling terminal (5).

4. The air conditioning system using the three-pipe technology according to claim 1, characterized in that: The throttling and pressure reducing valve (11) is an electronic expansion valve.

5. The air conditioning system using the three-pipe technology according to claim 1, characterized in that: The heating circuit also includes a heat collector (10) for heat supply balance. The input and output ends of the heat collector (10) are connected to the first medium-pressure pipeline (7) and the high-pressure pipeline (6) respectively, for supplementing heat supply when the compressor (1) is insufficient.

6. The air conditioning system using the three-pipe technology according to claim 5, characterized in that: The solar collector (10) includes a heat-absorbing plate for heat absorption and a heat conduction pipe for heat conduction. The first medium-pressure pipe (7) and the high-pressure pipe (6) are respectively connected to the two ends of the heat conduction pipe. A throttling and pressure-reducing valve (11) is installed at the end of the first medium-pressure pipe (7) connected to the solar collector (10). The throttling and pressure-reducing valve (11) is used to reduce the pressure of the medium-temperature and medium-pressure liquid refrigerant to a low-temperature and low-pressure liquid state.

7. The air conditioning system using the three-pipe technology according to claim 6, characterized in that: The heat-absorbing plate is used to absorb heat from sunlight when there is plenty of sunshine and / or absorb the temperature from the outside air when the outdoor temperature is higher than the temperature inside the first medium-pressure pipe on cloudy days.

8. The air conditioning system using the three-pipe technology according to claim 6, characterized in that: The heat absorption plate has two layers, and the heat conduction pipe is located between the two heat absorption plates.

9. The air conditioning system using the three-pipe technology according to claim 6, characterized in that: The heat conduction pipe is a serpentine pipe.

10. The air conditioning system using the three-pipe technology according to claim 6, characterized in that: The heat-absorbing plate is a solar photovoltaic panel, and a storage battery is connected to the end of the solar photovoltaic panel. The storage battery is connected to the compressor (1).

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