A full-operating-condition evaporative cooling composite split air-conditioning unit and control method

Abstract

A full-operating-condition evaporative cooling composite split air-conditioning unit and control method, which relate to the technical field of energy-saving technology for refrigeration and air-conditioning equipment. The full-operating-condition evaporative cooling composite split air-conditioning unit comprises an indoor unit and an outdoor unit. The indoor unit is provided with an air supply system and an exhaust system, and the outdoor unit is provided with an outdoor air system. Heat and mass exchange equipment such as an air-water surface heat exchanger, an air-refrigerant surface heat exchanger or a sprayer is provided in each air system, and each heat and mass exchange equipment is reasonably connected through pipelines to form a variety of heat exchanger loops. The air supply system comprises a fresh air inlet, a first air chamber, a second air chamber and an air supply port, and is provided with a plurality of adjustable air valves for air volume adjustment and path control. The present invention can cover typical climate conditions throughout the year with a variety of operating modes through appropriate heat exchanger loops and air valve state switching, thereby achieving full-operating-condition energy-saving goals.

Description

Technical Field

[0001] The present invention relates to the technical field of energy-saving of refrigeration and air-conditioning equipment, and in particular to a full-operating-mode evaporative cooling composite split air-conditioning unit and a control method thereof. Background Art

[0002] At present, the air conditioning of the building environment mainly relies on the conventional split air-conditioning system, which consists of an indoor unit (single or multiple indoor units) and an outdoor unit (single or multiple outdoor units), which are installed indoors and outdoors respectively.

[0003] Conventional split air conditioning systems are difficult to achieve stable indoor temperature and humidity comfort under different climatic conditions, or they need to pay the price of high energy consumption. For example, under hot climatic conditions, conventional split systems work in cooling mode, with only temperature as the control target, and cannot meet humidity requirements. Under mild and humid climatic conditions in the transition season, they work in dehumidification mode, with only humidity as the control target, resulting in low indoor temperature and temperature comfort cannot be guaranteed. Under dry climatic conditions, due to the lack of humidification function, the indoor air will be relatively dry and cannot meet humidity requirements. In order to achieve stable indoor temperature and humidity levels, under humid climatic conditions, conventional split air conditioning systems need to perform appropriate reheating after cooling and dehumidifying the indoor air to achieve a suitable supply air temperature. However, there is a phenomenon of mutual cancellation of cold and heat energy in this process, resulting in a large amount of energy waste. Under hot or cold and dry climatic conditions, the air conditioning system also needs to be equipped with a humidifier to moderately humidify the indoor air. For conventional split air conditioning systems, humidification and reheating are usually provided by low-efficiency electric steam humidifiers and electric heaters, respectively, which leads to high overall energy consumption and low energy efficiency of the air conditioning system.

[0004] The split mechanical compression system is combined with the evaporative cooler to form an evaporative cooling composite air conditioning system, which can not only give full play to the energy-saving advantages of evaporative cooling technology, but also ensure stable cooling / heating capacity, providing an effective way to optimize the structure of the split air conditioning system. However, in the existing composite system solution, the evaporative cooler is only used as a pre-cooling unit for the evaporator or condenser of the mechanical compression system, and is only suitable for hot and dry or hot and humid climates. It does not have multi-climate adaptability and it is difficult to achieve efficient and energy-saving operation throughout the year.

[0005] In addition, conventional small and medium-sized split air conditioning systems generally do not consider the organized introduction of fresh air. If the organized introduction of fresh air is considered, it will lead to a surge in the energy consumption of the air conditioning system. Although the energy consumption of fresh air can be reduced by setting up energy recovery equipment, some heat exchangers in conventional energy recovery equipment still have problems such as low recovery efficiency or cross-contamination risks. Summary of the invention

[0006] One of the purposes of the present invention is to provide a full-operating-condition evaporative cooling compound split air-conditioning unit, which, through appropriate heat exchanger loop and air valve state switching, covers typical climatic conditions throughout the year with multiple operating modes to achieve energy-saving goals under all operating conditions.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solution: a full-condition evaporative cooling composite split air-conditioning unit, comprising an indoor unit and an outdoor unit, the indoor unit is provided with an air supply system and an exhaust system, and the outdoor unit is provided with an outdoor air system.

[0008] The air supply system includes a fresh air inlet, a first air chamber, a second air chamber and an air supply port which are connected in sequence, a first air-water surface heat exchanger is arranged in the first air chamber, a first air supply bypass valve is arranged between the first air chamber and the second air chamber and the first air supply bypass valve is located in the air flow upstream direction of the first air-water surface heat exchanger, a first air-refrigerant surface heat exchanger is connected between the first air chamber and the second air chamber and the first air-refrigerant surface heat exchanger is located in the air flow downstream direction of the first air-water surface heat exchanger, a second air supply bypass valve and a third air supply bypass valve are arranged between the second air chamber and the air supply port, a second air-water surface heat exchanger is arranged in the second air chamber located between the second air supply bypass valve and the third air supply bypass valve, and a sprayer is also arranged in the first air chamber.

[0009] The exhaust system includes an exhaust inlet, an exhaust chamber and an exhaust outlet which are connected in sequence. A first water-sprayed packed bed heat exchanger is arranged in the exhaust chamber. The first water-sprayed packed bed heat exchanger is connected to the first air-water surface heat exchanger through a water pipe. The exhaust system is connected to the air supply system through a return air regulating valve. The return air regulating valve is located in the air flow upstream direction of the first water-sprayed packed bed heat exchanger, the air flow downstream direction of the first air-water surface heat exchanger, and the air flow upstream direction of the first air-refrigerant surface heat exchanger.

[0010] The outdoor air system includes a compressor, an outdoor air inlet, a third air-water surface heat exchanger, a third air-refrigerant surface heat exchanger, a second water-sprayed packed bed heat exchanger, a second air-refrigerant surface heat exchanger, and an outdoor air exhaust port, which are connected in sequence. The compressor can be connected to the first air-refrigerant surface heat exchanger, the second air-refrigerant surface heat exchanger, and the third air-refrigerant surface heat exchanger through a pipeline. The second air-refrigerant surface heat exchanger can be connected to the first air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger through a pipeline. The second water-sprayed packed bed heat exchanger can be connected to the second air-water surface heat exchanger and / or the third air-water surface heat exchanger through a pipeline. An electronic expansion valve is provided on the pipeline connecting the second air-refrigerant surface heat exchanger to the first air-refrigerant surface heat exchanger.

[0011] Furthermore, an exhaust side water distributor is provided on the top of the first water-sprayed packed bed heat exchanger and an exhaust side water pool is provided on the bottom. The exhaust side water pool transports water to the first air-water surface heat exchanger through a first water pump. The first air-water surface heat exchanger is connected to the exhaust side water distributor through a pipeline to return water.

[0012] Furthermore, the sprayer is connected to a spray pump through a pipe, the water inlet end of the spray pump is connected to an external water supply pipeline through a pipe, an indoor water receiving pan is provided below the sprayer, the indoor water receiving pan is connected to the exhaust side water pool through a water recovery pump, and the first air-refrigerant surface heat exchanger is located above the indoor water receiving pan.

[0013] Furthermore, the second water-sprayed packed bed heat exchanger is provided with an outdoor water distributor on the top and an outdoor water pool on the bottom. The outdoor water pool transports water to the outdoor water distributor or the second air-water surface heat exchanger and / or the third air-water surface heat exchanger through a third water pump. The third air-water surface heat exchanger is connected to a second water pump for transporting water to the second air-water surface heat exchanger.

[0014] Furthermore, the output end of the third water pump is connected to the third port of the first water circulation three-way solenoid valve through a pipeline, and the first port and the second port of the first water circulation three-way solenoid valve are respectively connected to the second air-water surface heat exchanger and the third air-water surface heat exchanger; the output end of the third water pump is also connected to the third port of the second water circulation three-way solenoid valve through a pipeline, and the second port of the second water circulation three-way solenoid valve is connected to the second air-water surface heat exchanger and / or the third air-water surface heat exchanger, and the first port is connected to the outdoor water distributor.

[0015] Furthermore, the exhaust port of the compressor is connected to the first port of the four-way reversing valve, the second port of the four-way reversing valve is connected to the first air-refrigerant surface heat exchanger through a pipeline, the third port of the four-way reversing valve is connected to the suction port of the compressor through a pipeline, and the fourth port of the four-way reversing valve is connected to the second air-refrigerant surface heat exchanger through a pipeline.

[0016] Furthermore, a first refrigerant flow regulating valve is provided on the pipe connecting the fourth port of the four-way reversing valve and the third air-refrigerant surface heat exchanger; a second refrigerant flow regulating valve is provided on the pipe connecting the second port of the four-way reversing valve and the first air-refrigerant surface heat exchanger.

[0017] Furthermore, the third air-refrigerant surface heat exchanger is connected to the first port of the first refrigerant circulation three-way solenoid valve through a pipeline and a first refrigerant flow regulating valve, the third port of the first refrigerant circulation three-way solenoid valve is connected to the pipeline from the second port of the four-way reversing valve to the second refrigerant flow regulating valve, and the second port of the first refrigerant circulation three-way solenoid valve is connected to the pipeline from the fourth port of the four-way reversing valve to the second air-refrigerant surface heat exchanger; the third air-refrigerant surface heat exchanger is also connected to the first port of the second refrigerant circulation three-way solenoid valve through a pipeline, the third port of the second refrigerant circulation three-way solenoid valve is connected to the pipeline from the first air-refrigerant surface heat exchanger to the electronic expansion valve, and the second port of the second refrigerant circulation three-way solenoid valve is connected to the pipeline from the second air-refrigerant surface heat exchanger to the electronic expansion valve.

[0018] Furthermore, the exhaust outlet is provided with an exhaust fan, the air supply outlet is provided with an air supply fan, the outdoor air exhaust outlet is provided with an outdoor fan, the exhaust air inlet is provided with an exhaust air filter section, and the fresh air inlet is provided with a fresh air filter section.

[0019] In addition, the present invention also provides a control method for the above-mentioned full-operating-mode evaporative cooling composite split air-conditioning unit, which implements the following operating modes through control instructions:

[0020] Cooling and dehumidification mode: turn on the supply fan, exhaust fan and outdoor fan, close the first supply air bypass valve and the third supply air bypass valve, open the second supply air bypass valve, close or moderately open the return air regulating valve, so that water circulates between the first water-sprayed packed bed heat exchanger and the first air-water surface heat exchanger, connect the compressor exhaust port to the second air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger so that the second air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger form a condenser, connect the compressor suction port to the first air-refrigerant surface heat exchanger so that the first air-refrigerant surface heat exchanger forms an evaporator, and connect the third air-water surface heat exchanger to the second air-water surface heat exchanger for Water circulation allows outdoor fresh air to enter through the fresh air inlet and undergo heat exchange with the first air-water surface heat exchanger for cooling and dehumidification, then undergo heat exchange with the first air-refrigerant surface heat exchanger for further cooling and dehumidification, then undergo heat exchange with the second air-water surface heat exchanger for appropriate heating, and finally be discharged to the supply air outlet through the second air supply bypass valve; indoor air enters from the exhaust air inlet and undergoes heat and moisture exchange with the first water-sprayed packed bed heat exchanger and then is discharged from the exhaust air outlet; outdoor air enters from the outdoor air inlet and passes through the third air-water surface heat exchanger, the third air-refrigerant surface heat exchanger, the second water-sprayed packed bed heat exchanger, and the second air-refrigerant surface heat exchanger in sequence and then is discharged from the outdoor air exhaust outlet.

[0021] Cooling mode: turn on the supply fan, exhaust fan and outdoor fan, close the first supply air bypass valve and the second supply air bypass valve, open the third supply air bypass valve, close or moderately open the return air regulating valve, so that water circulates between the first water-sprayed packed bed heat exchanger and the first air-water surface heat exchanger, connect the compressor exhaust port to the second air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger so that the second air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger form a condenser, connect the compressor suction port to the first air-refrigerant surface heat exchanger so that the first air-refrigerant surface heat exchanger forms an evaporator, and allow the refrigerant after heat exchange in the first air-refrigerant surface heat exchanger to enter the compressor, so that the high-temperature and high-pressure gaseous refrigerant from the compressor flows into the second air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger respectively, so that the refrigerant from the second air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger form an evaporator. The liquid refrigerant after heat exchange in the heat exchanger is cooled and depressurized by the electronic expansion valve, so that the two-phase refrigerant after cooling and depressurization flows into the first air-refrigerant surface heat exchanger for cooling and air supply, so that the second water-spraying packed bed heat exchanger is connected to the third air-water surface heat exchanger for water circulation so that the third air-water surface heat exchanger cools the outdoor air, so that the outdoor fresh air enters through the fresh air inlet and exchanges heat with the first air-water surface heat exchanger to cool it, and then exchanges heat with the first air-refrigerant surface heat exchanger to further cool it, and finally is discharged to the air supply port through the third air supply bypass valve; the indoor air enters from the exhaust air inlet and is discharged from the exhaust air outlet after heat and moisture exchange with the first water-spraying packed bed heat exchanger; the outdoor air enters from the outdoor air inlet and passes through the third air-water surface heat exchanger, the third air-refrigerant surface heat exchanger, the second water-spraying packed bed heat exchanger, and the second air-refrigerant surface heat exchanger in sequence, and is discharged from the outdoor air exhaust port.

[0022] Evaporative cooling mode: turn on the supply fan, exhaust fan and outdoor fan, close the second supply bypass valve, open the first supply bypass valve and the third supply bypass valve, close the return air regulating valve, turn on the sprayer, turn off the compressor, make the first water-sprayed packed bed heat exchanger and the first air-water surface heat exchanger circulate water, make the second water-sprayed packed bed heat exchanger connected in parallel with the second air-water surface heat exchanger and the third air-water surface heat exchanger for water circulation, make the outdoor fresh air enter through the fresh air inlet and be divided into two streams, one of which passes through the first air-water surface heat exchanger and is cooled, and then passes through the sprayer to be humidified and further cooled. The temperature is then released, and then the air enters the second air chamber through the first air-refrigerant surface heat exchanger which is not in operation. Another stream of fresh air passes through the first air supply bypass valve and then passes through the second air-water surface heat exchanger and is cooled. Then the two streams of air are mixed and discharged to the air supply port through the third air supply bypass valve. The indoor air enters from the exhaust air inlet and is discharged from the exhaust air outlet after undergoing heat and moisture exchange with the first water-sprayed packed bed heat exchanger. The outdoor air enters from the outdoor air inlet and passes through the third air-water surface heat exchanger, the third air-refrigerant surface heat exchanger, the second water-sprayed packed bed heat exchanger, and the second air-refrigerant surface heat exchanger in sequence. The outdoor air is discharged from the outdoor air exhaust port.

[0023] Heating mode: turn on the supply fan, exhaust fan and outdoor fan, close the first supply air bypass valve and the second supply air bypass valve, open the third supply air bypass valve, close or moderately open the return air regulating valve, turn on the sprayer, allow water to circulate between the first water-sprayed packed bed heat exchanger and the first air-water surface heat exchanger, close the second water-sprayed packed bed heat exchanger, connect the compressor exhaust port to the first air-refrigerant surface heat exchanger so that the first air-refrigerant surface heat exchanger forms a condenser, and connect the compressor suction port to the second air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger so that the second air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger form an evaporator. The liquid refrigerant after heat exchange in the first air-refrigerant surface heat exchanger passes through the electronic expansion valve and then flows to the second air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger respectively, so that fresh air from the outside enters through the fresh air inlet and exchanges heat with the first air-water surface heat exchanger for heating, then is humidified by the sprayer, and then is supplemented with heating by the first air-refrigerant surface heat exchanger, and finally is discharged to the supply air outlet through the third air supply bypass valve; indoor air enters from the exhaust air inlet and is discharged from the exhaust air outlet after heat and moisture exchange with the first water-sprayed packed bed heat exchanger; outdoor air enters from the outdoor air inlet and passes through the third air-water surface heat exchanger, the third air-refrigerant surface heat exchanger, the second water-sprayed packed bed heat exchanger, and the second air-refrigerant surface heat exchanger in sequence.

[0024] Heating and defrosting mode: turn on the supply air fan and the exhaust air fan, turn on the outdoor fan and keep it running at a low speed, close the first supply air bypass valve and the second supply air bypass valve, open the third supply air bypass valve, close or moderately open the return air regulating valve, close the sprayer, make water circulate between the first water-sprayed packed bed heat exchanger and the first air-water surface heat exchanger, close the second water-sprayed packed bed heat exchanger, connect the compressor exhaust port to the first air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger so that the first air-refrigerant surface heat exchanger and the third air-refrigerant surface heat exchanger form a condenser, connect the compressor suction port to the second air-refrigerant surface heat exchanger so that the second air-refrigerant surface heat exchanger forms an evaporator, and allow the liquid refrigerant after heat exchange in the first air-refrigerant surface heat exchanger to pass through the electronic expansion valve, Then it flows to the second air-refrigerant surface heat exchanger, so that the third air-refrigerant surface heat exchanger forms a condenser, thereby defrosting the surfaces of the third air-refrigerant surface heat exchanger and the second air-refrigerant surface heat exchanger, so that outdoor fresh air enters through the fresh air inlet and exchanges heat with the first air-water surface heat exchanger for heating, and then passes through the first air-refrigerant surface heat exchanger for further heating, and finally is discharged to the supply air outlet through the third supply air bypass valve; indoor air enters from the exhaust air inlet and is discharged from the exhaust air outlet after exchanging heat and moisture with the first water-sprayed packed bed heat exchanger; outdoor air enters from the outdoor air inlet and passes through the third air-water surface heat exchanger, the third air-refrigerant surface heat exchanger, the second water-sprayed packed bed heat exchanger, and the second air-refrigerant surface heat exchanger in sequence.

[0025] Ventilation mode: turn on the supply fan and exhaust fan, turn off the outdoor fan, open the first supply air bypass valve and the second supply air bypass valve, turn off the first water-sprayed packed bed heat exchanger, the second water-sprayed packed bed heat exchanger and the compressor, so that air enters through the fresh air inlet, and then is discharged to the supply outlet through the first supply air bypass valve and the second supply air bypass valve; the indoor air enters through the exhaust air inlet and is discharged from the exhaust air outlet.

[0026] The beneficial effects of the present invention are that through mode switching, it can have multiple functions such as exhaust energy recovery, evaporative cooling, evaporative condensation, multi-climate adaptation, adjustable fresh air volume and flat-to-failure conversion, which can greatly reduce fresh air energy consumption, avoid electric auxiliary heating and electric humidification energy consumption, and improve the energy efficiency of mechanical steam compression cycle. More importantly, even if the mode is switched, the various components will still maintain coordinated operation, rather than the corresponding components only operating in the corresponding operating mode, which makes the working efficiency very high. Therefore, the full-operating-mode evaporative cooling composite split air-conditioning unit can adapt to complex climate changes while achieving high-efficiency and energy-saving operation throughout the year, thereby improving indoor air quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0028] Figure 2 This is a schematic diagram of the principle of the cooling and dehumidification mode in Example 1;

[0029] Figure 3 This is a schematic diagram of the principle of the cooling mode in Example 2;

[0030] Figure 4 This is a schematic diagram of the principle of the evaporative cooling mode in Example 3;

[0031] Figure 5 This is a schematic diagram of the principle of the heating mode in Example 4;

[0032] Figure 6 This is a schematic diagram of the principle of the heating and defrosting mode in Example 5;

[0033] Figure 7 This is a schematic diagram of the principle of the ventilation mode in Example 6.

[0034] The accompanying drawings are marked as follows:

[0035] 1. Indoor unit; 2. Outdoor unit; 3. Second air-refrigerant surface heat exchanger; 4. Third air-water surface heat exchanger; 5. Third air-refrigerant surface heat exchanger; 6. First air-water surface heat exchanger; 7. Second air-water surface heat exchanger; 8. First air-refrigerant surface heat exchanger; 9. First water-sprayed packed bed heat exchanger; 10. Second water-sprayed packed bed heat exchanger; 11. Exhaust side water distributor; 12. Outdoor side water distributor; 13. Exhaust fan; 14. Supply fan; 15. Outdoor fan; 16. Return air regulating valve; 17. First supply air bypass valve; 18. Second supply air bypass valve; 19. Third supply air bypass valve; 20. Exhaust air inlet; 21. Exhaust air outlet; 22. Fresh air inlet; 23. Supply air outlet; 24. Outdoor air exhaust port; 25. Outdoor air inlet port; 26. Exhaust filter section; 27. Fresh air filter section; 28. Sprayer; 29. ​​First water pump; 30. Second water pump; 31. Third water pump; 32. Sprayer pump; 33. Water recovery pump; 34. Exhaust side pool drain valve; 35. Exhaust side pool water replenishment valve; 36. Outdoor side pool drain valve; 37. Outdoor side pool water replenishment valve; 38. First water circulation three-way solenoid valve; 39. Second water circulation three-way solenoid valve; 40. First refrigerant flow regulating valve; 41. Second refrigerant flow regulating valve; 42. First refrigerant circulation three-way solenoid valve; 43. Second refrigerant circulation three-way solenoid valve; 44. Electronic expansion valve; 45. Compressor; 46. Four-way reversing valve; 47. Exhaust side pool; 48. Outdoor water pool; 49. Indoor water tray; 50. Outdoor water tray. DETAILED DESCRIPTION

[0036] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the implementation modes are not intended to limit the present invention.

[0037] It should be noted in advance that, in the present invention, unless otherwise clearly specified and limited, the terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the present invention, unless otherwise clearly specified and limited, the first feature "on" or "under" the second feature may include the first and second features being in direct contact, and may also include the first and second features not being in direct contact but being in contact through another feature between them.

[0038] like Figure 1As shown, a full-operating-condition evaporative cooling composite split air-conditioning unit mainly comprises an indoor unit 1 and an outdoor unit 2. The indoor unit 1 is provided with an air supply system and an air exhaust system, and the outdoor unit 2 is provided with an outdoor air system.

[0039] Among them, the air supply system includes a fresh air inlet 22, a fresh air filter section 27, a first supply air bypass valve 17, a first air-water surface heat exchanger 6, a return air regulating valve 16, a sprayer 28, a first air-refrigerant surface heat exchanger 8, a third supply air bypass valve 19, a second air-water surface heat exchanger 7, a second supply air bypass valve 18, a supply air fan 14, and an air supply port 23; the exhaust system includes an exhaust air inlet 20, an exhaust air filter section 26, a first water-sprayed packed bed heat exchanger 9 (including an exhaust side water distributor 11), an exhaust fan 13, and an exhaust air outlet 21, and the air supply system and the exhaust system are connected through the return air regulating valve 16.

[0040] The outdoor air system includes an outdoor air inlet 25, a third air-water surface heat exchanger 4, a third air-refrigerant surface heat exchanger 5, a second water-sprayed packed bed heat exchanger 10 (including an outdoor water distributor 12), a second air-refrigerant surface heat exchanger 3, an outdoor fan 15, an outdoor air exhaust port 24, and an outdoor water pool 48.

[0041] In the above structure, the first air supply bypass valve 17, the second air supply bypass valve 18 and the third air supply bypass valve 19 are all equipped with an opening control system. The first air supply bypass valve 17 is installed upstream of the air flow of the first air-water surface heat exchanger 6, and is connected to the second air-water surface heat exchanger 7 and the second air supply bypass valve 18. The third air supply bypass valve 19 is installed between the first air-refrigerant surface heat exchanger 8 and the second air-water surface heat exchanger 7, and is connected to the air supply port 23. The second air-water surface heat exchanger 7 is arranged between the second air supply bypass valve 18 and the third air supply bypass valve 19.

[0042] The air supply system is provided with a water spray system for air humidification, including a sprayer 28, a spray pump 32 and a connecting water pipeline. The sprayer 28 is installed in the air flow downstream direction of the first air-water surface heat exchanger 6 and the return air regulating valve 16, and is located in the air flow upstream direction of the first air-refrigerant surface heat exchanger 8.

[0043] The air supply system is also provided with a water recovery system, including an indoor water receiving tray 49, a water recovery pump 33 and a connecting water pipeline. The water source of the water recovery system is the unevaporated droplets after spraying by the sprayer 28 or the condensed water dripping on the surface of the first air-refrigerant surface heat exchanger 8. The water outlet of the water recovery system is arranged at the upper end of the exhaust side water pool 47, and the recovered water flows into the exhaust side water pool 47.

[0044] The outdoor air system is also provided with a water recovery system, including an outdoor water tray 50 and corresponding connecting pipes. The installation height of the outdoor water tray 50 is slightly higher than the outdoor water pool 48 to ensure that the recovered water in the outdoor water tray 50 can smoothly flow into the outdoor water pool 48. If the above installation height is difficult to meet, the technicians in this field can equip a small water delivery pump according to the actual situation.

[0045] The above-mentioned return air regulating valve 16 is also equipped with an opening control system and is installed between the first air-water surface heat exchanger 6 and the first air-refrigerant surface heat exchanger 8 .

[0046] The specific settings of the pipe connection of the above-mentioned full-operating evaporative cooling composite split air-conditioning unit are as follows:

[0047] The first air-water surface heat exchanger 6 is connected to the water distributor 11 of the first water-spraying packed bed heat exchanger 9 through a water pipe L29, the exhaust side water pool 47 is connected to the first water pump 29 through a water pipe L31, and the first water pump 29 is connected to the first air-water surface heat exchanger 6 through a water pipe L30. In general, the exhaust side water pool 47, the water pipe L31, the first water pump 29, the water pipe L30, the first air-water surface heat exchanger 6, the water pipe L29 and the first water-spraying packed bed heat exchanger 9 constitute an indoor indirect evaporative cooling loop.

[0048] The second air-water surface heat exchanger 7 is connected to the first port of the first water circulation three-way solenoid valve 38 through the water pipeline L19, the second port of the first water circulation three-way solenoid valve 38 is connected to the third air-water surface heat exchanger 4 through the water pipeline L23, the third air-water surface heat exchanger 4 is connected to the second water pump 30 through the water pipeline L22, and the second water pump 30 is connected to the second air-water surface heat exchanger 7 through the water pipelines L21 and L20. In general, the second water pump 30, the water pipeline L21, the water pipeline L20, the second air-water surface heat exchanger 7, the water pipeline L19, the first port and the second port of the first water circulation three-way solenoid valve 38, the water pipeline L23, the third air-water surface heat exchanger 4 and the water pipeline L22 constitute an air supply reheat loop.

[0049] The first port of the second water circulation three-way solenoid valve 39 is connected to the water distributor 12 of the second water-spraying packed bed heat exchanger 10 through the water pipeline L25, the outdoor water pool 48 is connected to the third water pump 31 through the water pipeline L27, and the third water pump 31 is connected to the third port of the second water circulation three-way solenoid valve 39 through the water pipeline L26. In general, the second water-spraying packed bed heat exchanger 10, the outdoor water pool 48, the water pipeline L27, the third water pump 31, the water pipeline L26, the third port and the first port of the second water circulation three-way solenoid valve 39, and the water pipeline L25 constitute an outdoor direct evaporation condensation loop.

[0050] The first air-refrigerant surface heat exchanger 8 is connected to the second refrigerant flow regulating valve 41 through the refrigerant pipeline L17, the refrigerant flow regulating valve 41 is connected to the second port of the four-way reversing valve 45 through the refrigerant pipelines L16 and L15, the third port of the four-way reversing valve 46 is connected to the suction port of the compressor 45 through the refrigerant pipeline L14, the exhaust port of the compressor 45 is connected to the first port of the four-way reversing valve 46 through the refrigerant pipeline L1, the fourth port of the four-way reversing valve 46 is connected to the second air-refrigerant surface heat exchanger 3 through the refrigerant pipelines L2 and L8, the second air-refrigerant surface heat exchanger 3 is connected to the electronic expansion valve 44 through the refrigerant pipelines L9 and L10, and the electronic expansion valve 44 is connected to the first air-refrigerant surface heat exchanger 8 through the refrigerant pipelines L11 and L18. In general, the first air-refrigerant surface heat exchanger 8, the refrigerant pipeline L17, the second refrigerant flow regulating valve 41, the refrigerant pipeline L16, the refrigerant pipeline L15, the second port and the third port of the four-way reversing valve 46, the refrigerant pipeline L14, the compressor 45, the refrigerant pipeline L1, the first port and the fourth port of the four-way reversing valve 46, the refrigerant pipeline L2, the refrigerant pipeline L8, the second air-refrigerant surface heat exchanger 3, the refrigerant pipeline L9, the refrigerant pipeline L10, the electronic expansion valve 44, the refrigerant pipeline L11 and the refrigerant pipeline L18 form a refrigeration cycle. When the second port of the four-way reversing valve 46 is connected to the first port, and the third port is connected to the fourth port, the above components are connected to form a heat pump cycle.

[0051] The air supply reheat loop is connected to the outdoor direct evaporation condensation loop through water pipes L24 and L28. Water pipe L24 connects the connection of water pipes L20 and L21 with the second port of the second water circulation three-way solenoid valve 39. Water pipe L28 connects the third port of the first water circulation three-way solenoid valve 38 with the third water pump 31. Water pipes L28 and L26 are both connected to the outlet of the third water pump 31.

[0052] The connection point of the refrigerant pipelines L2 and L8 is connected to the second port of the first refrigerant circulation three-way solenoid valve 42 through the refrigerant pipeline L3, the first port of the first refrigerant circulation three-way solenoid valve 42 is connected to the first refrigerant flow regulating valve 40 through the refrigerant pipeline L4, the first refrigerant flow regulating valve 40 is connected to the third air-refrigerant surface heat exchanger 5 through the refrigerant pipeline L5, the third air-refrigerant surface heat exchanger 5 is connected to the first port of the second refrigerant circulation three-way solenoid valve 43 through the refrigerant pipeline L6, and the second port of the second refrigerant circulation three-way solenoid valve 43 is connected to the connection point of the refrigerant pipelines L9 and L10 through the refrigerant pipeline L7. In general, the refrigerant pipeline L3, the second port and the first port of the first refrigerant circulation three-way solenoid valve 42, the refrigerant pipeline L4, the first refrigerant flow regulating valve 40, the refrigerant pipeline L5, the third air-refrigerant surface heat exchanger 5, the refrigerant pipeline L6, the first port and the second port of the second refrigerant circulation three-way solenoid valve 43 and the refrigerant pipeline L7 constitute a refrigerant bypass exhaust / heat absorption auxiliary pipeline.

[0053] The connection point of the refrigerant pipelines L15 and L16 is connected to the third port of the first refrigerant circulation three-way solenoid valve 42 through the refrigerant pipeline L13, and the connection point of the refrigerant pipelines L11 and L18 is connected to the third port of the second refrigerant circulation three-way solenoid valve 43 through the refrigerant pipeline L12. In general, the refrigerant pipeline L13, the third port and the first port of the first refrigerant circulation three-way solenoid valve 42, the refrigerant pipeline L4, the first refrigerant flow regulating valve 40, the refrigerant pipeline L5, the third air-refrigerant surface heat exchanger 5, the refrigerant pipeline L6, the first port and the third port of the second refrigerant circulation three-way solenoid valve 43, and the refrigerant pipeline L12 constitute a refrigerant bypass defrosting pipeline.

[0054] The following describes the control method of the full-operating evaporative cooling compound split air-conditioning unit under six typical operating modes. Example

[0055] Cooling and dehumidification mode: Figure 2As shown, when the climate is hot and humid or mild and humid, the cooling and dehumidification mode is started, the first air supply bypass valve 17 is closed, the second air supply bypass valve 18 remains fully open, the third air supply bypass valve 19 is closed, the return air regulating valve 16 is moderately opened (remains closed in the fresh air mode), the exhaust fan 13, the air supply fan 14 and the outdoor fan 15 are all turned on, the first water pump 29, the second water pump 30 and the third water pump 31 are all turned on, the spray pump 32 remains closed, and the first port and the second port of the first water circulation three-way solenoid valve 38 are connected. The first port of the second water circulation three-way solenoid valve 39 is connected to the third port, the first port of the four-way reversing valve 46 is connected to the fourth port, the second port is connected to the third port, the first port of the first refrigerant circulation three-way solenoid valve 42 is connected to the second port, the first port of the second refrigerant circulation three-way solenoid valve 43 is connected to the second port, the first air-refrigerant surface heat exchanger 8 serves as an evaporator, and the second air-refrigerant surface heat exchanger 3 and the third air-refrigerant surface heat exchanger 5 both serve as condensers.

[0056] In the cooling and dehumidification mode, fresh air enters from the fresh air inlet 22, is properly filtered by the fresh air filter section 27, flows through the first air-water surface heat exchanger 6 to be cooled or even dehumidified, and then is mixed with part of the return air from the return air regulating valve 16. If the fresh air is required, the return air regulating valve 16 remains closed. Since the mixed supply air may still not meet the supply air temperature and humidity requirements, it needs to be deeply cooled and dehumidified by the evaporator first air-refrigerant surface heat exchanger 8, and then properly reheated by the second air-water surface heat exchanger 7 to avoid discomfort to indoor personnel caused by overcooling of the supply air. Finally, under the conveying action of the supply air fan 14, the supply air enters the air-conditioned room through the second supply air bypass valve 18 and the supply air outlet 23 in turn. Indoor air enters from the exhaust air inlet 20, and after being properly filtered by the exhaust air filter section 26, it flows through the first water-spraying packed bed heat exchanger 9 (including the exhaust side water distributor 11), directly contacts with the circulating water, and undergoes direct evaporative cooling, the enthalpy value increases, and the circulating water temperature decreases. Finally, under the conveying action of the exhaust fan 13, it is discharged from the exhaust air outlet 21. Outdoor air enters from the outdoor air inlet 25, and undergoes heat exchange with the third air-water surface heat exchanger 4 to be cooled. After that, the cooled outdoor air flows through the third air-refrigerant surface heat exchanger 5 to be heated, and then flows through the second water-spraying packed bed heat exchanger 10 (including the outdoor side water distributor 12), directly contacts with the circulating water, and undergoes direct evaporative cooling, the temperature decreases, the moisture content increases, and then flows through the second air-refrigerant surface heat exchanger 3 to be heated again. Finally, it is discharged from the outdoor air exhaust port 24 under the conveying action of the outdoor fan 15.

[0057] In the cooling and dehumidification mode, the first water-sprayed packed bed heat exchanger 9 (including the exhaust side water distributor 11), the first air-water surface heat exchanger 6, the first water pump 29 and the corresponding water pipelines (L29-L31) constitute an indoor indirect evaporative cooling loop. The second air-water surface heat exchanger 7, the third air-water surface heat exchanger 4, the second water pump 30, the first water circulation three-way solenoid valve 38 and the corresponding water pipelines (L19-L23) constitute an air supply reheat loop. The second water-sprayed packed bed heat exchanger 10 (including the outdoor side water distributor 12), the third water pump 31, the second water circulation three-way solenoid valve 39 and the corresponding water pipelines (L25-L27) constitute an outdoor direct evaporative condensation loop. The first air-refrigerant surface heat exchanger 8, the second air-refrigerant surface heat exchanger 3, the third air-refrigerant surface heat exchanger 5, the compressor 45, the electronic expansion valve 44, the four-way reversing valve 46, the first refrigerant flow regulating valve 40, the second refrigerant flow regulating valve 41 and the corresponding refrigerant pipelines (L1-L11, L14-L18) constitute a double condenser refrigeration cycle. Example

[0058] Cooling mode: Figure 3 As shown, when the climate is hot and the humidity is suitable, the cooling and dehumidification mode is started, the first air supply bypass valve 17 is closed, the second air supply bypass valve 18 is closed, the third air supply bypass valve 19 remains fully open, the return air regulating valve 16 is moderately opened (remains closed in the fresh air mode), the exhaust fan 13, the air supply fan 14 and the outdoor fan 15 are all turned on, the third water pump 31 is turned on, the first water pump 29 is turned on, and if the outdoor temperature is low and the fresh air cannot be cooled, the second water pump 30 is turned off (the circulating water can be reversed or bypassed), the spray pump 32 is kept closed, and the first water circulation pump 31 is turned on. The second port of the three-way solenoid valve 38 is connected to the third port, the first port of the second water circulation three-way solenoid valve 39 is connected to the second port, the first port of the four-way reversing valve 46 is connected to the fourth port, and the second port is connected to the third port, the first port of the first refrigerant circulation three-way solenoid valve 42 is connected to the second port, the first port of the second refrigerant circulation three-way solenoid valve 43 is connected to the second port, the first air-refrigerant surface heat exchanger 8 serves as an evaporator, and the second air-refrigerant surface heat exchanger 3 and the third air-refrigerant surface heat exchanger 5 both serve as condensers.

[0059] In the cooling mode, after the fresh air is sucked in from the fresh air inlet 22, it is first properly filtered by the fresh air filter section 27, then cooled by the first air-water surface heat exchanger 6, and then mixed with part of the return air from the return air regulating valve 16. If the fresh air is required, the return air regulating valve 16 remains closed. Since the mixed supply air may still not meet the supply air temperature requirement, it needs to be further cooled by the high-temperature evaporator first air-refrigerant surface heat exchanger 8. Finally, under the conveying action of the supply air fan 14, the supply air passes through the third supply air bypass valve 19 and the supply air port 23 in sequence into the air-conditioned room. The exhaust air and outdoor air flow paths are consistent with the cooling and dehumidification mode of the embodiment.

[0060] In the cooling mode, the second water-sprayed packed bed heat exchanger 10 (including the outdoor water distributor 12), the third water pump 31, the third air-water surface heat exchanger 4, the first water circulation three-way solenoid valve 38, the second water circulation three-way solenoid valve 39 and the corresponding water pipelines (L21-L25, L27-L28) constitute an outdoor indirect evaporative condensation loop. The indoor indirect evaporative cooling loop and the double condenser refrigeration cycle are consistent with the cooling and dehumidification mode of the embodiment. Example 3

[0061] Evaporative cooling mode: Figure 4 As shown, when the climate is hot and dry and the air enthalpy is low, the evaporative cooling mode is started, the first air supply bypass valve 17 is moderately opened, the second air supply bypass valve 18 is closed, the third air supply bypass valve 19 remains fully open, the return air regulating valve 16 is closed, the exhaust fan 13, the air supply fan 14 and the outdoor fan 15 are all turned on, the first water pump 29 and the third water pump 31 are turned on, the second water pump 30 is turned off, the spray pump 32 is turned on, the third port of the first water circulation three-way solenoid valve 38 is connected to the first port and the second port, the first port of the second water circulation three-way solenoid valve 39 is connected to the second port, the compressor 45 is shut down, and the refrigerant cycle does not work.

[0062] In the evaporative cooling mode, after the fresh air is sucked in from the fresh air inlet 22, it is first properly filtered by the fresh air filter section 27, and then divided into two streams. One stream passes through the first air-water surface heat exchanger 6 to be cooled, and then passes through the sprayer 28 to be cooled and humidified, and then passes through the first air-refrigerant surface heat exchanger 8 (not working). The other stream of fresh air passes through the first air supply bypass valve 17, and then flows through the second air-water surface heat exchanger 7 to be cooled. The two streams of fresh air are mixed before the third air supply bypass valve 19, and finally, under the conveying action of the air supply fan 14, they pass through the third air supply bypass valve 19 and the air supply port 23 in sequence to enter the air-conditioned room. The exhaust air and outdoor air flow paths are consistent with the cooling and dehumidification mode of the embodiment.

[0063] In the evaporative cooling mode, the second water-sprayed packed bed heat exchanger 10 (including the outdoor water distributor 12), the second air-water surface heat exchanger 7, the third air-water surface heat exchanger 4, the third water pump 31, the first water circulation three-way solenoid valve 38, the second water circulation three-way solenoid valve 39 and the corresponding water pipelines (L19-L25, L27-L28) constitute an outdoor dew point indirect evaporative cooling loop. The indoor indirect evaporative cooling loop is consistent with the cooling and dehumidification mode of the embodiment. Example

[0064] Heating mode: Figure 5 As shown, when the climate is cold and dry, the heating mode is started, the first air supply bypass valve 17 is closed, the second air supply bypass valve 18 is closed, the third air supply bypass valve 19 remains fully open, the return air regulating valve 16 is moderately opened (remains closed in the fresh air mode), the exhaust fan 13, the air supply fan 14 and the outdoor fan 15 are all turned on, the first water pump 29 is turned on, the third water pump 31 and the second water pump 30 are turned off, the spray pump 32 is turned on, the first port of the four-way reversing valve 45 is connected to the second port, the third port is connected to the fourth port, the first port of the first refrigerant circulation three-way solenoid valve 42 is connected to the second port, the first port of the second refrigerant circulation three-way solenoid valve 43 is connected to the second port, and the first refrigerant flow regulating valve 40 and the second refrigerant flow regulating valve 41 remain fully open. The first air-refrigerant surface heat exchanger 8 serves as a condenser, and the second air-refrigerant surface heat exchanger 3 and the third air-refrigerant surface heat exchanger 5 both serve as evaporators.

[0065] In the heating mode, fresh air enters from the fresh air inlet 22, is properly filtered by the fresh air filter section 27, is heated by the first air-water surface heat exchanger 6, and then is mixed with part of the return air from the return air regulating valve 16. If the fresh air is required, the return air regulating valve 16 remains closed. Since the mixed supply air may still not meet the supply air temperature and humidity requirements, the sprayer 28 sprays the mixed supply air appropriately to humidify and cool it, and then it is supplemented by the condenser first air-refrigerant surface heat exchanger 8. Finally, under the conveying action of the supply air fan 14, the supply air passes through the third supply air bypass valve 19 and the supply air port 23 in turn into the air-conditioned room. The exhaust air first passes through the exhaust air inlet 20 and the exhaust air filter section 26, and then flows through the first water-spraying packed bed heat exchanger 9 (including the exhaust side water distributor 11) to undergo reverse evaporative cooling, releasing the condensation heat to heat the circulating water, and finally, under the conveying action of the exhaust fan 13, it is discharged from the exhaust air outlet 21. Under the conveying action of the outdoor fan 15, the outdoor air flows through the outdoor air inlet 25, the third air-water surface heat exchanger 4 (not working), the third air-refrigerant surface heat exchanger 5, the second water-sprayed packed bed heat exchanger 10 (including the outdoor water distributor 12) (not working), the second air-refrigerant surface heat exchanger 3 in sequence, and finally is discharged from the outdoor air outlet 24 under the conveying action of the outdoor fan 15. The third air-refrigerant surface heat exchanger 5 and the second air-refrigerant surface heat exchanger 3 both act as evaporators to absorb the heat of the outdoor air and reduce the outdoor air temperature.

[0066] In the heating mode, the first water-sprayed packed bed heat exchanger 9 (including the exhaust side water distributor 11), the first air-water surface heat exchanger 6, the first water pump 29 and the corresponding water pipelines (L29-L31) constitute an indoor indirect (reverse) evaporative cooling loop. The first air-refrigerant surface heat exchanger 8, the second air-refrigerant surface heat exchanger 3, the third air-refrigerant surface heat exchanger 5, the compressor 45, the electronic expansion valve 44, the four-way reversing valve 46, the first refrigerant flow regulating valve 40, the second refrigerant flow regulating valve 41 and the corresponding refrigerant pipelines (L1-L11, L14-L18) constitute a double evaporator heat pump cycle. Example

[0067] Heating defrost mode: Figure 6As shown, the difference between this embodiment and embodiment 4 is that: when the climate is cold but defrosting is required, the heating defrosting mode is started, the spray pump 32 is turned off, the outdoor fan 15 runs at a low speed, the first port of the first refrigerant circulation three-way solenoid valve 42 is connected to the third port, the first port of the second refrigerant circulation three-way solenoid valve 43 is connected to the third port, and the second refrigerant flow regulating valve 41 is properly opened and can be adjusted according to the defrosting effect, or even completely closed. The first air-refrigerant surface heat exchanger 8 and the third air-refrigerant surface heat exchanger 5 are both used as condensers, the second air-refrigerant surface heat exchanger 3 is used as an evaporator, and the states of the remaining components are consistent with the above heating mode. The fresh air, exhaust air, and outdoor air paths are consistent with the heating mode of the above embodiment, and the condenser third air-refrigerant surface heat exchanger 5 is switched to the condenser state for rapid defrosting, and the outdoor air is heated to defrost the evaporator second air-refrigerant surface heat exchanger 3. If the defrosting effect of the second air-refrigerant surface heat exchanger 3 still does not meet expectations, the defrosting can be enhanced by switching the four-way reversing valve 46 .

[0068] In this mode, the first air-refrigerant surface heat exchanger 8, the second air-refrigerant surface heat exchanger 3, the third air-refrigerant surface heat exchanger 5, the compressor 45, the electronic expansion valve 44, the four-way reversing valve 46, the first refrigerant flow regulating valve 40, the second refrigerant flow regulating valve 41 and the corresponding refrigerant pipelines (L1-L11, L14-L18) constitute a double condenser heat pump cycle. The indoor indirect (reverse) evaporative cooling loop is consistent with the heating mode of the above embodiment. Example

[0069] Ventilation mode: Figure 7 As shown, when the ventilation mode is started when the climate is suitable in the transition season, the first air supply bypass valve 17 and the second air supply bypass valve 18 remain fully open, the exhaust fan 13 and the supply fan 14 are turned on, and the other components do not work. After the fresh air is sucked in from the fresh air inlet 22, it is first properly filtered by the fresh air filter section 27, and then the fresh air passes through the first air supply bypass valve 17, the second air supply bypass valve 18 and the air supply port 23 in sequence under the conveying action of the supply fan 14 to enter the air-conditioned room. The exhaust air passes through the exhaust air inlet 20, the exhaust air filter section 26, the first water-spraying packed bed heat exchanger 9 (including the exhaust side water distributor 11) (does not work) in sequence, and finally is discharged from the exhaust air outlet 21 under the conveying action of the exhaust fan 13.

[0070] It can be seen from the above embodiments that the indoor indirect evaporative cooling loop works in the cooling and dehumidification, cooling and evaporative cooling modes. Under the pumping action of the first water pump 29, the cold water in the exhaust side pool 47 flows into the first air-water surface heat exchanger 6 to cool the fresh air. When the fresh air humidity is high, it can even dehumidify the fresh air. The low-temperature circulating water absorbs the heat of the fresh air and then heats up. It then enters the exhaust side water distributor 11 and is evenly sprinkled on the first water-spraying packed bed heat exchanger 9. The exhaust air flows from bottom to top through the first water-spraying packed bed heat exchanger 9, and directly evaporates and cools the circulating water flowing through the first water-spraying packed bed heat exchanger 9 under the action of gravity. The exhaust air enthalpy increases and the circulating water temperature decreases. In theory, the lower limit temperature of the circulating water is the exhaust air inlet wet-bulb temperature. Finally, the circulating water drops back to the exhaust side pool 47 to complete the cycle. Functionally, the indoor indirect evaporative cooling loop realizes full heat recovery of exhaust air. Other full heat recovery devices can also achieve this function, such as plate-type indirect evaporative coolers, rotary heat recovery devices, membrane plate heat recovery devices, etc.

[0071] The air supply reheat loop works in the cooling and dehumidification mode. The fresh air that has undergone deep cooling and dehumidification exchanges heat with the circulating water in the second air-water surface heat exchanger 7. The fresh air is reheated, the temperature rises, and the temperature of the circulating water drops. Under the pumping action of the second water pump 30, the circulating water flows through the first port and the second port of the first water circulation three-way solenoid valve 38, flows into the third air-water surface heat exchanger 4, exchanges heat with the outdoor air, cools the outdoor air, reduces the inlet air temperature of the third air-refrigerant surface heat exchanger 5, and then reduces the condensation pressure and improves the efficiency of the compressor 45. Afterwards, the circulating water heated by the outdoor air flows back to the second air-water surface heat exchanger 7, reheats the fresh air again, and completes the cycle.

[0072] The outdoor direct evaporation condensation loop works in the cooling and dehumidification mode. Under the pumping action of the third water pump 31, the cold water in the outdoor water pool 48 is transported to the outdoor water distributor 12 and evenly sprinkled on the second water-spraying packed bed heat exchanger 10. Under the action of gravity, the circulating water slowly flows through the second water-spraying packed bed heat exchanger 10 and directly contacts the outdoor air from bottom to top, and a direct evaporative cooling effect occurs. The outdoor air is cooled and humidified by isenthalpy. The cooled outdoor air flows through the second air-refrigerant surface heat exchanger 3 of the condenser to reduce the condensation pressure and improve the efficiency of the compressor 45. The circulating water temperature drops. In theory, the circulating water temperature can be close to the wet bulb temperature of the air inlet state (the air outlet state of the third air-refrigerant surface heat exchanger 5). After that, the cooled circulating water drops back to the outdoor water pool 48 to complete the cycle.

[0073] The outdoor indirect evaporative condensation loop works in the cooling mode. Under the pumping action of the third water pump 31, the cold water in the outdoor water pool 48 is transported to the third air-water surface heat exchanger 4 to cool the outdoor air. The cooled outdoor air can reduce the condensation pressure of the condenser third air-refrigerant surface heat exchanger 5, thereby achieving the purpose of improving the efficiency of the compressor 45. The circulating water heated by the outdoor air flows back to the outdoor water distributor 12 and is evenly sprinkled on the second water-spraying packed bed heat exchanger 10. Under the action of gravity, the circulating water slowly flows through the second water-spraying packed bed heat exchanger 10 and directly contacts the outdoor air from bottom to top, resulting in evaporative cooling, reducing the inlet air temperature of the second air-refrigerant surface heat exchanger 3, and further improving the efficiency of the compressor 45. Finally, the circulating water temperature drops and drips back to the outdoor water pool 48 to complete the cycle.

[0074] The outdoor dew point indirect evaporative cooling loop works in the evaporative cooling mode. Under the pumping action of the third water pump 31, the cold water in the outdoor water pool 48 is respectively transported to the first air-water surface heat exchanger 7 and the third air-water surface heat exchanger 4 to cool a fresh air and outdoor air respectively, and then flows back to the outdoor water distributor 12. Under the action of gravity, it flows through the second water-spraying packed bed heat exchanger 10, directly contacts with the outdoor air from bottom to top, and directly evaporatively cools, and finally drips back to the outdoor water pool 48 to complete the cycle. In this process, the outdoor air is pre-cooled by the third air-water surface heat exchanger 4 and then flows through the second water-spraying packed bed heat exchanger 10 to directly evaporatively cool, and the cooling effect is enhanced. In theory, the temperature of the circulating water dripping back to the outdoor water pool 48 can be cooled to a dew point temperature close to the outdoor air state.

[0075] The indoor indirect (reverse) evaporative cooling loop works in the heating and heating defrosting modes. Under the pumping action of the first water pump 29, the hot water in the exhaust side pool 47 flows into the first air-water surface heat exchanger 6 to heat the fresh air. The high-temperature circulating water absorbs the cold air and then cools down. It then enters the exhaust side water distributor 11 and is evenly sprinkled on the first water-spraying packed bed heat exchanger 9. The high-temperature and high-humidity exhaust air flows from bottom to top through the first water-spraying packed bed heat exchanger 9 and directly contacts the low-temperature circulating water flowing through the first water-spraying packed bed heat exchanger 9 under the action of gravity. The water vapor in the exhaust air condenses and releases the condensation heat, which is the reverse evaporative cooling effect. The exhaust air enthalpy decreases and the circulating water temperature rises. Finally, the heated circulating water drops back to the exhaust side pool 47 to complete the cycle.

[0076] The double condenser refrigeration cycle works in the cooling and dehumidification and cooling modes. Under the action of the compressor 45, the high-temperature and high-pressure gaseous refrigerant enters the second air-refrigerant surface heat exchanger 3 of the condenser and the third air-refrigerant surface heat exchanger 5 of the condenser, exchanges heat with the outdoor air, and releases the condensation heat while heating the outdoor air to form liquid refrigerant. The outdoor air entering the third air-refrigerant surface heat exchanger 5 is precooled by the third air-water surface heat exchanger 4, and the outdoor air entering the second air-refrigerant surface heat exchanger 3 is precooled by the second water-spraying packed bed heat exchanger 10 (including the outdoor side water distributor 12). The condensation pressure of the refrigerant cycle decreases, and the efficiency of the compressor 45 is improved. After passing through the electronic expansion valve 44, the temperature and pressure of the high-temperature and high-pressure liquid refrigerant decreases, and it flows into the first air-refrigerant surface heat exchanger 8 of the evaporator to perform deep cooling and dehumidification (low evaporation pressure, suitable for cooling and dehumidification mode) or sensible cooling (high evaporation pressure, suitable for cooling mode) on the supply air. The refrigerant that has absorbed the heat is sucked into the compressor 45 again, completing the cycle.

[0077] The double evaporator heat pump cycle works in the heating mode. Under the action of the compressor 45, the high-temperature and high-pressure gaseous refrigerant enters the first air-refrigerant surface heat exchanger 8 of the condenser, exchanges heat with the supply air, and releases the condensation heat while heating the supply air to form a liquid refrigerant. After the high-temperature and high-pressure liquid refrigerant passes through the electronic expansion valve 44, the temperature and pressure drop, and it flows into the second air-refrigerant surface heat exchanger 3 of the evaporator and the third air-refrigerant surface heat exchanger 5 of the evaporator respectively, exchanges heat with the outdoor air, absorbs the heat of the outdoor air, and becomes a gaseous refrigerant, which is sucked into the compressor 45 again to complete the cycle.

[0078] The double condenser heat pump cycle works in the heating defrosting mode. Under the action of the compressor 45, the high-temperature and high-pressure gaseous refrigerant is divided into two paths. One path flows into the third air-refrigerant surface heat exchanger 5 of the condenser for rapid defrosting, and heats the outdoor air to defrost the second air-refrigerant surface heat exchanger 3 of the evaporator. The other path of refrigerant flows into the first air-refrigerant surface heat exchanger 8 of the condenser to appropriately reheat the supply air. The flow of this path of refrigerant is controlled by the refrigerant flow valve 41, which can be appropriately adjusted according to the defrosting effect, or even completely closed. After that, the high-temperature and high-pressure liquid refrigerant passes through the electronic expansion valve, and the temperature and pressure drop, and flows into the second air-refrigerant surface heat exchanger 3 of the evaporator, exchanges heat with the outdoor air, absorbs the heat of the outdoor air, and is sucked into the compressor 45 again to complete the cycle. On the other hand, if the defrosting effect of the second air-refrigerant surface heat exchanger 3 does not meet expectations, the defrosting can be enhanced by switching the four-way reversing valve 46. In this mode, the third air-refrigerant surface heat exchanger 5 and the second air-refrigerant surface heat exchanger 3 serve as an evaporator and a condenser to each other respectively.

[0079] The full-condition evaporative cooling composite split air-conditioning unit provided in the above-mentioned implementation method fully utilizes the design flexibility of evaporative cooling technology, and has multiple functions such as exhaust energy recovery, evaporative cooling, evaporative condensation, multi-climate adaptation, and peacetime-epidemic conversion. At the same time, the system also has multiple operating modes, which can achieve high-efficiency and energy-saving operation throughout the year while adapting to complex climate changes. The system structure is not complex and the implementation difficulty is not great. It can adapt to year-round operation and peacetime-epidemic conversion conditions at a low energy consumption cost, thereby improving indoor air quality.

[0080] In order to make it easier for ordinary technicians in the field to understand the improvements of the present invention over the prior art, some drawings and descriptions of the present invention have been simplified, and the above-mentioned embodiments are preferred implementation schemes of the present invention. In addition, the present invention can also be implemented in other ways. Any obvious replacement without departing from the concept of the present technical solution is within the protection scope of the present invention.

Claims

1. A full-operation evaporative cooling composite split air-conditioning unit, comprising an indoor unit (1) and an outdoor unit (2), characterized in that: The indoor unit (1) is provided with an air supply system and an air exhaust system, and the outdoor unit (2) is provided with an outdoor air system; The air supply system comprises a fresh air inlet (22), a first air chamber, and a fresh air inlet (22) connected in sequence. I 、Second air chamber II and an air supply port (23), the first air chamber I A first air-water surface heat exchanger (6) is provided inside the first air chamber. I With the second air chamber II A first air supply bypass valve (17) is provided between the first air supply bypass valve (17) and the first air supply bypass valve (17) is located in the air flow upstream direction of the first air-water surface heat exchanger (6). I With the second air chamber II A first air-refrigerant surface heat exchanger (8) is connected therebetween and the first air-refrigerant surface heat exchanger (8) is located in the air flow downstream direction of the first air-water surface heat exchanger (6), and the second air chamber II A second air supply bypass valve (18) and a third air supply bypass valve (19) are provided between the air supply port (23); a second air-water surface heat exchanger (7) is provided in the second air chamber between the second air supply bypass valve (18) and the third air supply bypass valve (19); I A sprayer (28) is also provided therein; The exhaust system comprises an exhaust air inlet (20), an exhaust air chamber and an exhaust air outlet (21) which are connected in sequence, a first water-sprayed packed bed heat exchanger (9) is arranged in the exhaust air chamber, the first water-sprayed packed bed heat exchanger (9) is connected to the first air-water surface heat exchanger (6) via a water pipe, the exhaust system is connected to the air supply system via a return air regulating valve (16), and the return air regulating valve (16) is located in the air flow upstream direction of the first water-sprayed packed bed heat exchanger (9), the air flow downstream direction of the first air-water surface heat exchanger (6), and the air flow upstream direction of the first air-refrigerant surface heat exchanger (8); The outdoor air system comprises a compressor (45), an outdoor air inlet (25) connected in sequence, a third air-water surface heat exchanger (4), a third air-refrigerant surface heat exchanger (5), a second water-sprayed packed bed heat exchanger (10), a second air-refrigerant surface heat exchanger (3), and an outdoor air exhaust port (24); the compressor (45) can be connected to the first air-refrigerant surface heat exchanger (8), the second air-refrigerant surface heat exchanger (3), and the third air-refrigerant surface heat exchanger through a pipeline. (5), the second air-refrigerant surface heat exchanger (3) can be connected to the first air-refrigerant surface heat exchanger (8) and the third air-refrigerant surface heat exchanger (5) through a pipeline, the second water-sprayed packed bed heat exchanger (10) can be connected to the second air-water surface heat exchanger (7) and / or the third air-water surface heat exchanger (4) through a pipeline, and an electronic expansion valve (44) is provided on the pipeline connecting the second air-refrigerant surface heat exchanger (3) and the first air-refrigerant surface heat exchanger (8).

2. The full-operation evaporative cooling composite split air-conditioning unit according to claim 1, characterized in that: The first water-sprayed packed bed heat exchanger (9) is provided with an exhaust side water distributor (11) at the top and an exhaust side water pool (47) at the bottom. The exhaust side water pool (47) transports water to the first air-water surface heat exchanger (6) via a first water pump (29). The first air-water surface heat exchanger (6) is connected to the exhaust side water distributor (11) via a pipeline to return water.

3. The full-operation evaporative cooling composite split air-conditioning unit according to claim 2, characterized in that: The sprayer (28) is connected to a spray pump (32) via a pipeline; a water inlet end of the spray pump (32) is connected to an external water supply pipeline via a pipeline; an indoor water receiving pan (49) is provided below the sprayer (28); the indoor water receiving pan (49) is connected to an exhaust side water pool (47) via a water recovery pump (33); and the first air-refrigerant surface heat exchanger (8) is located above the indoor water receiving pan (49).

4. The full-operation evaporative cooling composite split air-conditioning unit according to claim 1, characterized in that: The second water-sprayed packed bed heat exchanger (10) is provided with an outdoor water distributor (12) at the top and an outdoor water pool (48) at the bottom. The outdoor water pool (48) delivers water to the outdoor water distributor (12) or the second air-water surface heat exchanger (7) and / or the third air-water surface heat exchanger (4) through a third water pump (31). The third air-water surface heat exchanger (4) is connected to a second water pump (30) for delivering water to the second air-water surface heat exchanger (7).

5. The full-operation evaporative cooling composite split air-conditioning unit according to claim 4, characterized in that: The output end of the third water pump (31) is connected to the third port of the first water circulation three-way solenoid valve (38) through a pipeline, and the first port and the second port of the first water circulation three-way solenoid valve (38) are respectively connected to the second air-water surface heat exchanger (7) and the third air-water surface heat exchanger (4); the output end of the third water pump (31) is also connected to the third port of the second water circulation three-way solenoid valve (39) through a pipeline, and the second port of the second water circulation three-way solenoid valve (39) is connected to the second air-water surface heat exchanger (7) and / or the third air-water surface heat exchanger (4), and the first port is connected to the outdoor water distributor (12).

6. The full-operation evaporative cooling composite split air-conditioning unit according to claim 1, characterized in that: The exhaust port of the compressor (45) is connected to the first port of the four-way reversing valve (46), the second port of the four-way reversing valve (46) is connected to the first air-refrigerant surface heat exchanger (8) through a pipeline, the third port of the four-way reversing valve (46) is connected to the suction port of the compressor (45) through a pipeline, and the fourth port of the four-way reversing valve (46) is connected to the second air-refrigerant surface heat exchanger (3) through a pipeline.

7. The full-operation evaporative cooling composite split air-conditioning unit according to claim 6, characterized in that: A first refrigerant flow regulating valve (40) is provided on the pipeline connecting between the fourth port of the four-way reversing valve (46) and the third air-refrigerant surface heat exchanger (5); and a second refrigerant flow regulating valve (41) is provided on the pipeline connecting between the second port of the four-way reversing valve (46) and the first air-refrigerant surface heat exchanger (8).

8. The full-operation evaporative cooling composite split air-conditioning unit according to claim 7, characterized in that: The third air-refrigerant surface heat exchanger (5) is connected to the first port of the first refrigerant circulation three-way solenoid valve (42) through a pipeline and a first refrigerant flow regulating valve (40); the third port of the first refrigerant circulation three-way solenoid valve (42) is connected to the pipeline between the second port of the four-way reversing valve (46) and the second refrigerant flow regulating valve (41); the second port of the first refrigerant circulation three-way solenoid valve (42) is connected to the pipeline between the fourth port of the four-way reversing valve (46) and the second air-refrigerant surface heat exchanger (3); the third air-refrigerant surface heat exchanger (5) is also connected to the first port of the second refrigerant circulation three-way solenoid valve (43) through a pipeline; the third port of the second refrigerant circulation three-way solenoid valve (43) is connected to the pipeline between the first air-refrigerant surface heat exchanger (8) and the electronic expansion valve (44); and the second port of the second refrigerant circulation three-way solenoid valve (43) is connected to the pipeline between the second air-refrigerant surface heat exchanger (3) and the electronic expansion valve (44).

9. The full-operation evaporative cooling composite split air-conditioning unit according to claim 1, characterized in that: The exhaust air outlet (21) is provided with an exhaust fan (13), the air supply outlet (23) is provided with an air supply fan (14), the outdoor air exhaust outlet (24) is provided with an outdoor fan (15), the exhaust air inlet (20) is provided with an exhaust air filter section (26), and the fresh air inlet (22) is provided with a fresh air filter section (27).

10. A control method for a full-operation evaporative cooling composite split air-conditioning unit according to any one of claims 1 to 9, characterized in that: The following operating modes are implemented through control commands: Cooling and dehumidification mode: the supply air fan (14), the exhaust air fan (13) and the outdoor fan (15) are turned on, the first supply air bypass valve (17) and the third supply air bypass valve (19) are closed, the second supply air bypass valve (18) is opened, the return air regulating valve (16) is closed or opened appropriately, water is circulated between the first water-sprayed packed bed heat exchanger (9) and the first air-water surface heat exchanger (6), the exhaust port of the compressor (45) is connected to the second air-refrigerant surface heat exchanger (3) and the third air-refrigerant surface heat exchanger (5) so that the second air-refrigerant surface heat exchanger (3) and the third air-refrigerant surface heat exchanger (5) form a condenser, the air intake port of the compressor (45) is connected to the first air-refrigerant surface heat exchanger (8) so that the first air-refrigerant surface heat exchanger (8) forms an evaporator, and the third air-water surface heat exchanger (4) is connected to the second air-water surface heat exchanger The heat exchanger (7) performs water circulation, so that outdoor fresh air enters through the fresh air inlet (22) and exchanges heat with the first air-water surface heat exchanger (6) to cool and dehumidify, then passes through the first air-refrigerant surface heat exchanger (8) to exchange heat to further cool and dehumidify, then passes through the second air-water surface heat exchanger (7) to exchange heat to be appropriately heated, and finally is discharged to the air supply port (23) through the second air supply bypass valve (18); indoor air enters through the exhaust air inlet (20) and exchanges heat and moisture with the first water-spraying packed bed heat exchanger (9) and is discharged from the exhaust air outlet (21); outdoor air enters through the outdoor air inlet (25) and passes through the third air-water surface heat exchanger (4), the third air-refrigerant surface heat exchanger (5), the second water-spraying packed bed heat exchanger (10), and the second air-refrigerant surface heat exchanger (3) in sequence, and is discharged from the outdoor air exhaust port (24); Cooling mode: start the air supply fan (14), the exhaust fan (13) and the outdoor fan (15), close the first air supply bypass valve (17) and the second air supply bypass valve (18), open the third air supply bypass valve (19), close or moderately open the return air regulating valve (16), so that water circulates between the first water-sprayed packed bed heat exchanger (9) and the first air-water surface heat exchanger (6), and connect the exhaust port of the compressor (45) to the second air-refrigerant surface heat exchanger (3) and the third air-refrigerant surface heat exchanger (5) so that the second air-refrigerant surface heat exchanger (9) and the third air-refrigerant surface heat exchanger (5) are connected. The air intake port of the compressor (45) is connected to the first air-refrigerant surface heat exchanger (8) so that the first air-refrigerant surface heat exchanger (8) forms an evaporator, and the refrigerant in the first air-refrigerant surface heat exchanger (8) after heat exchange enters the compressor (45), and the high-temperature and high-pressure gaseous refrigerant from the compressor (45) flows into the second air-refrigerant surface heat exchanger (3) and the third air-refrigerant surface heat exchanger (5) respectively to exchange heat with outdoor air and condense. The condensed refrigerant is cooled and depressurized by passing through an electronic expansion valve (44), and the cooled and depressurized two-phase refrigerant is returned to the first air-refrigerant surface heat exchanger (8) to cool the supply air, and the second water-sprayed packed bed heat exchanger (10) is connected to the third air-water surface heat exchanger (4) to perform water circulation so that the third air-water surface heat exchanger (4) cools the outdoor air, and the outdoor fresh air enters through the fresh air inlet (22) and exchanges heat with the first air-water surface heat exchanger (6) to cool the air, and then passes through the first air-refrigerant surface heat exchanger (8). Heat exchange is performed to further cool the air, and the air is finally discharged to the air supply port (23) through the third air supply bypass valve (19); indoor air enters through the exhaust air inlet (20) and is discharged through the exhaust air outlet (21) after heat and moisture exchange with the first water-sprayed packed bed heat exchanger (9); outdoor air enters through the outdoor air inlet (25) and passes through the third air-water surface heat exchanger (4), the third air-refrigerant surface heat exchanger (5), the second water-sprayed packed bed heat exchanger (10), and the second air-refrigerant surface heat exchanger (3) in sequence, and is discharged through the outdoor air exhaust port (24); Evaporative cooling mode: the supply air fan (14), the exhaust air fan (13) and the outdoor fan (15) are turned on, the second supply air bypass valve (18) is closed, the first supply air bypass valve (17) and the third supply air bypass valve (19) are opened, the return air regulating valve (16) is closed, the sprayer (28) is turned on, the compressor (45) is turned off, water is circulated between the first water-sprayed packed bed heat exchanger (9) and the first air-water surface heat exchanger (6), the second water-sprayed packed bed heat exchanger (10) is connected in parallel to the second air-water surface heat exchanger (7) and the third air-water surface heat exchanger (4) for water circulation, and outdoor fresh air enters through the fresh air inlet (22) and is divided into two streams, one of which passes through the first air-water surface heat exchanger (6) and is cooled, then passes through the sprayer (28) to be humidified and further cooled, and then enters the second air chamber through the non-operating first air-refrigerant surface heat exchanger (8). II , another stream of fresh air passes through the first air supply bypass valve (17) and then passes through the second air-water surface heat exchanger (7) and is cooled, and then the two streams of air are mixed and discharged to the air supply port (23) through the third air supply bypass valve (19); indoor air enters through the exhaust air inlet (20) and is discharged from the exhaust air outlet (21) after undergoing heat and moisture exchange with the first water-sprayed packed bed heat exchanger (9); outdoor air enters through the outdoor air inlet (25) and passes through the third air-water surface heat exchanger (4), the third air-refrigerant surface heat exchanger (5), the second water-sprayed packed bed heat exchanger (10), and the second air-refrigerant surface heat exchanger (3) in sequence, and is discharged from the outdoor air exhaust port (24); Heating mode: start the air supply fan (14), the exhaust fan (13) and the outdoor fan (15), close the first air supply bypass valve (17) and the second air supply bypass valve (18), open the third air supply bypass valve (19), close or appropriately open the return air regulating valve (16), open the sprayer (28), allow water to circulate between the first water-sprayed packed bed heat exchanger (9) and the first air-water surface heat exchanger (6), close the second water-sprayed packed bed heat exchanger (10), and exhaust the compressor (45) The air inlet of the compressor (45) is connected to the first air-refrigerant surface heat exchanger (8) so that the first air-refrigerant surface heat exchanger (8) forms a condenser, the air inlet of the compressor (45) is connected to the second air-refrigerant surface heat exchanger (3) and the third air-refrigerant surface heat exchanger (5) so that the second air-refrigerant surface heat exchanger (3) and the third air-refrigerant surface heat exchanger (5) form an evaporator, and the liquid refrigerant after heat exchange in the first air-refrigerant surface heat exchanger (8) is passed through the air inlet of the compressor (45) to form an evaporator. The temperature and pressure of the two-phase refrigerant are reduced by the electronic expansion valve (44), and the two-phase refrigerant after the temperature and pressure reduction flows to the second air-refrigerant surface heat exchanger (3) and the third air-refrigerant surface heat exchanger (5), respectively, so that the outdoor fresh air enters through the fresh air inlet (22) and exchanges heat with the first air-water surface heat exchanger (6) to be heated, and then humidified by the sprayer (28), and then supplemented by the first air-refrigerant surface heat exchanger (8), and finally passes through the third air supply bypass valve (19). ) is discharged toward the air supply port (23); indoor air enters through the exhaust air inlet (20) and is discharged from the exhaust air outlet (21) after undergoing heat and moisture exchange with the first water-sprayed packed bed heat exchanger (9); outdoor air enters through the outdoor air inlet (25) and passes through the third air-water surface heat exchanger (4), the third air-refrigerant surface heat exchanger (5), the second water-sprayed packed bed heat exchanger (10), and the second air-refrigerant surface heat exchanger (3) in sequence before being discharged from the outdoor air exhaust port (24); Heating defrosting mode: start the air supply fan (14) and the exhaust fan (13), start the outdoor fan (15) and keep it running at a low speed, close the first air supply bypass valve (17) and the second air supply bypass valve (18), open the third air supply bypass valve (19), close or moderately open the return air regulating valve (16), close the sprayer (28), allow water to circulate between the first water-sprayed packed bed heat exchanger (9) and the first air-water surface heat exchanger (6), close the second water-sprayed packed bed heat exchanger (10), and connect the exhaust port of the compressor (45) to the first The air-refrigerant surface heat exchanger (8) and the third air-refrigerant surface heat exchanger (5) are connected so that the first air-refrigerant surface heat exchanger (8) and the third air-refrigerant surface heat exchanger (5) form a condenser, the air intake port of the compressor (45) is connected to the second air-refrigerant surface heat exchanger (3) so that the second air-refrigerant surface heat exchanger (3) forms an evaporator, and the liquid refrigerant after heat exchange in the first air-refrigerant surface heat exchanger (8) and the third air-refrigerant surface heat exchanger (5) is evaporating through the electronic expansion chamber. The expansion valve (44) is cooled and depressurized, so that the two-phase refrigerant after cooling and depressurization flows back to the second air-refrigerant surface heat exchanger (3), so that the third air-refrigerant surface heat exchanger (5) forms a condenser, thereby defrosting the surfaces of the third air-refrigerant surface heat exchanger (5) and the second air-refrigerant surface heat exchanger (3), allowing outdoor fresh air to enter through the fresh air inlet (22) and exchange heat with the first air-water surface heat exchanger (6) to be heated, and then further heated through the first air-refrigerant surface heat exchanger (8). The air is finally discharged to the air supply port (23) through the third air supply bypass valve (19); the indoor air enters through the exhaust air inlet (20) and is discharged from the exhaust air outlet (21) after undergoing heat and moisture exchange with the first water-sprayed packed bed heat exchanger (9); the outdoor air enters through the outdoor air inlet (25) and passes through the third air-water surface heat exchanger (4), the third air-refrigerant surface heat exchanger (5), the second water-sprayed packed bed heat exchanger (10), and the second air-refrigerant surface heat exchanger (3) in sequence, before being discharged from the outdoor air exhaust port (24); Ventilation mode: turn on the supply air fan (14) and the exhaust air fan (13), turn off the outdoor fan (15), open the first supply air bypass valve (17) and the second supply air bypass valve (18), turn off the first water-sprayed packed bed heat exchanger (9), the second water-sprayed packed bed heat exchanger (10) and the compressor (45), so that air enters through the fresh air inlet (22) and is then discharged to the supply air outlet (23) through the first supply air bypass valve (17) and the second supply air bypass valve (18); indoor air enters through the exhaust air inlet (20) and is then discharged through the exhaust air outlet (21).

Images