Fresh air handling unit

Abstract

The utility model discloses a fresh air handling unit which comprises a draught fan shell, a fresh air inlet and a fresh air outlet are formed in the two side faces of the draught fan shell respectively, a draught fan section is arranged at the position, close to the fresh air outlet, in the draught fan shell and comprises an EC draught fan wall, a plurality of draught fans are installed in the EC draught fan wall, and a first partition plate and a second partition plate are arranged in the draught fan shell at intervals. The first partition plate is connected with the second partition plate through a third partition plate, a first electric valve is arranged on the first partition plate, a second electric valve is arranged on the second partition plate, a third electric valve is arranged on the third partition plate, and a filtering section, an empty section and a heat exchange coil section are arranged below the first partition plate, the second partition plate and the third partition plate. Through opening of different electric valves, operation under various working conditions can be achieved, the working conditions of the minimum fresh air volume and the maximum fresh air volume can be flexibly switched, meanwhile, the frequency of the draught fan can be automatically adjusted according to the change of pipeline impedance, the fresh air volume is kept to be matched with the designed air volume, and the energy-saving effect of operation of the fresh air handling unit is remarkable.

Description

Technical Field

[0001] This utility model belongs to the field of electromechanical equipment technology, specifically relating to a fresh air handling unit. Background Technology

[0002] Fresh air handling units are a type of fresh air treatment equipment widely used in the HVAC field and are an important component of air conditioning system energy consumption. However, the fresh air handling units currently on the market mainly have the following problems:

[0003] 1) Currently, the fresh air handling units on the market have a single working mode and cannot be adjusted to the optimal working mode according to the size of the fresh air demand or the variability of the climate throughout the year. They cannot meet the need to increase the fresh air volume during transitional seasons or when outdoor conditions change.

[0004] 2) Regardless of whether the outdoor air quality is good or not, the fresh air handling unit always needs to overcome the resistance of components such as filters and heat exchange coils during operation. Especially in the medical field, the filter resistance is often large. Overcoming the filter resistance often greatly increases the energy consumption of the fan, making the operation not energy-efficient, which is contrary to the current concept of energy conservation and emission reduction.

[0005] 3) Due to the significant difference between the estimated impedance of the air system during design and the actual construction and commissioning, it is difficult to match the designed air volume of the fresh air handling unit with the actual commissioning air volume, making commissioning difficult. The air pressure of the fresh air handling unit is often selected to be too large, which leads to the artificial addition of resistance components and the increase of pipeline resistance to match the fresh air handling unit, increasing the energy consumption of the fan. Moreover, as the filter resistance increases, the air volume of the fresh air handling unit will gradually decrease, making it impossible to provide a relatively stable fresh air volume to the room, affecting the comfort of the indoor occupants.

[0006] Therefore, this utility model proposes a fresh air handling unit that can flexibly switch between minimum and maximum fresh air volume operation conditions. Utility Model Content

[0007] In view of the problems existing in the prior art, the purpose of this utility model is to provide a fresh air handling unit that can achieve operation under multiple working conditions, and at the same time solve the hidden danger of heat exchange coil freezing and cracking when the indoor fresh air is provided with free cooling in winter.

[0008] To achieve the above objectives, the technical solution of this utility model is as follows:

[0009] A fresh air handling unit includes a fan housing with a fresh air inlet and a fresh air outlet on both sides. A fan section is located inside the fan housing near the fresh air outlet. The fan section includes an EC fan wall, within which several fans are installed. A partition 1 and a partition 2 are spaced apart inside the fan housing and connected by a partition 3. An electric valve 1 is mounted on partition 1, and electric valves 2 and 3 are mounted on partitions 2 and 3, respectively. Below partitions 1, 2, and 3 are a filter section, an air section, and a heat exchange coil section.

[0010] Furthermore, the filter section includes a filter located below the third partition plate, the first partition plate has an air inlet for the filter section, the fourth partition plate is provided between the filter section and the empty section, and the fourth partition plate has a ventilation opening.

[0011] Furthermore, a partition plate five is provided between the empty section and the heat exchange coil section, and an electric valve four is provided on the partition plate five.

[0012] Furthermore, the heat exchange coil section includes a heat exchange coil located below the third partition plate, and the second partition plate is provided with an air outlet for the heat exchange coil section.

[0013] Furthermore, a PM2.5 sensor is installed between the fresh air inlet and the partition, and an air volume sensor is installed between the EC fan wall and the fresh air outlet.

[0014] Furthermore, the fan is a variable frequency unit, and its maximum air volume is configured to be twice the rated fresh air volume under air conditioning conditions.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0016] 1) The new air handling unit of this utility model is equipped with electric valves on four partitions. By opening different electric valves, it can realize various operating conditions and flexibly switch between minimum and maximum fresh air volume conditions. At the same time, it can automatically adjust the fan frequency according to the change of pipeline impedance to keep the fresh air volume matching the design air volume. The fresh air handling unit has significant energy-saving effect and has good market application and promotion value.

[0017] 2) When the fresh air bypass is in operation, when the outdoor air quality is good, electric valves 1 and 2 will be opened automatically, and electric valves 3 and 4 will be closed. Fresh air is delivered to the air-conditioned room after passing through electric valves 1 and 2 and the EC fan wall. The fresh air unit does not need to overcome the resistance of the filter and heat exchange coil, which can save operating energy.

[0018] 3) The air outlet of this utility model unit is equipped with an air volume sensor, which automatically adjusts the frequency of the EC fan wall fan according to the change of pipeline impedance, saving fan energy consumption. At the same time, it can accurately match the design and required air volume without secondary debugging, reducing the workload of debugging and greatly improving operability. In addition, when the outdoor air enthalpy value is lower than the indoor air value during the transition season or at night, the fresh air volume can be increased to save operating energy consumption.

[0019] 4) When the rooms in the inner zone need cooling in winter, the fresh air unit can operate in the fresh air bypass mode to use fresh air for cooling, and there is no problem of the heat exchange coil freezing and cracking in winter, which perfectly solves the cooling problem of the inner zone rooms. Attached Figure Description

[0020] Figure 1 This is a plan view of the fresh air handling unit of this utility model;

[0021] Figure 2 This is a simplified diagram illustrating an application example of the fresh air handling unit of this utility model.

[0022] In the diagram: 1. Fan casing; 2. Fresh air inlet; 3. Fresh air outlet; 4. EC fan wall; 5. Fan; 6. Partition 1; 7. Partition 2; 8. Partition 3; 9. Electric valve 1; 10. Electric valve 2; 11. Electric valve 3; 12. Filter; 13. Partition 4; 14. Partition 5; 15. Electric valve 4; 16. Heat exchange coil; 17. PM2.5 sensor; 18. Air volume sensor; 19. Control cabinet; 20. Temperature sensor; 21. Humidity sensor; 22. Electric valve 5. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited to the scope described.

[0024] Please refer to Figure 1 A fresh air handling unit includes a fan housing 1. Fresh air inlets 2 and fresh air outlets 3 are respectively provided on both sides of the fan housing 1. A fan section is provided inside the fan housing 1 near the fresh air outlets 3. The fan section includes an EC fan wall 4. A plurality of fans 5 are installed inside the EC fan wall 4. A partition 1 6 and a partition 2 7 are provided inside the fan housing 1 at intervals. The partition 1 6 and the partition 2 7 are connected by a partition 3 8. The partition 1 6, the partition 2 7 and the partition 3 8 form a bypass section.

[0025] Electric valve 9 is installed on partition 16, and electric valve 10 and electric valve 11 are installed on partition 27 and partition 38 respectively. Filter section, air section and heat exchange coil section are provided below partition 16, partition 27 and partition 38.

[0026] The filter section includes a filter 12, which is located below the partition 3 8. The filter section air inlet is located below the partition 1 6. The filter section and the empty section are separated by a partition 4 13, which has a ventilation opening.

[0027] Furthermore, a partition plate 514 is provided between the empty section and the heat exchange coil section, and an electric air valve 415 is provided on the partition plate 514.

[0028] The heat exchange coil section includes heat exchange coil 16, which is located below partition 3 8. Partition 2 7 is provided with an air outlet for the heat exchange coil section.

[0029] A PM2.5 sensor 17 is installed between the fresh air inlet 2 and the partition 6, and an air volume sensor 18 is installed between the EC fan wall 4 and the fresh air outlet 3.

[0030] In this embodiment, there are 3 fans 5. Fan 5 is a variable frequency unit, and its maximum air volume is configured to be twice the rated fresh air volume when the air conditioning is in operation.

[0031] In this embodiment, a control cabinet 19 is also included, which is installed at the front end of the fan housing 1. The opening and closing of electric valve 9, electric valve 10, electric valve 11, and electric valve 15 are all controlled by the control cabinet 19.

[0032] Control cabinet 19 collects data from PM2.5 sensor 17 and air volume sensor 18 and adjusts the frequency and number of EC variable frequency fans.

[0033] The operating principle of the fresh air handling unit of this invention is as follows:

[0034] (i) When the air conditioning is in operation, if the outdoor air quality is good, the electric valve 19, electric valve 31, and electric valve 415 will be opened automatically, and electric valve 210 will be closed. Fresh air will pass through electric valve 19, electric valve 31, air section, electric valve 415, heat exchange coil 16, and EC fan wall 4 before being delivered to the air-conditioned room. The fresh air unit does not need to overcome the resistance of filter 12, which can save operating energy. If the outdoor air quality is poor, electric valve 19 and electric valve 31 will be closed, electric valve 210 will be kept closed, and electric valve 415 will be opened. Fresh air will pass through filter 12, air section, electric valve 415, heat exchange coil 16, and EC fan wall 4 before being delivered to the air-conditioned room.

[0035] (ii) When the fresh air bypass is in operation, when the outdoor air quality is good, the electric valve 19 and electric valve 210 will be opened automatically, and the electric valve 31 and electric valve 415 will be closed. The fresh air is delivered to the air-conditioned room after passing through the electric valve 19, electric valve 210 and EC fan wall 4. The fresh air unit does not need to overcome the resistance of the filter 12 and heat exchange coil 16, which can save operating energy consumption.

[0036] When the outdoor air quality is poor, close electric valve 19 and electric valve 20, and open electric valve 31 and electric valve 415. Fresh air passes through the filter section, air section, electric valve 415, electric valve 311, and EC fan wall 4, and is then sent into the air-conditioned room. The fresh air unit does not need to overcome the resistance of the heat exchange coil. Example 1

[0037] Figure 2 For a building's fresh air supply case, a temperature sensor 20 and a humidity sensor 21 are installed on the fresh air intake duct. The heat exchange coil 16 is connected to the air conditioning supply and return water pipes. The air conditioning return water pipe is equipped with an electric valve 22. A temperature sensor 20 is installed on the fresh air supply duct. The fresh air supply duct is led to the air-conditioned room.

[0038] Temperature sensor 20, humidity sensor 21, the control circuits of the fresh air handling unit control cabinet, the temperature sensor on the fresh air supply duct, and the electric regulating valve of the air conditioning supply and return water pipeline are all connected to the automatic control system. The specific application steps are as follows:

[0039] (i) The automatic control system compares the outdoor air enthalpy value measured by the temperature sensor and humidity sensor on the fresh air intake duct with the indoor air enthalpy value to determine that the cooling in summer and the heating in winter will operate at the minimum fresh air volume. A PM2.5 sensor 17 is installed at the fresh air intake of the unit. When the PM2.5 sensor 17 detects a value lower than the set value, electric valve 19 and electric valve 31 are opened, and electric air valve 20 and electric air valve 415 are closed. When the PM2.5 sensor 17 detects a value higher than the set value, electric air valve 415 is opened, and electric valve 19, electric air valve 20 and electric valve 31 are closed.

[0040] (ii) The automatic control system compares the outdoor air enthalpy value with the indoor air enthalpy value based on the temperature sensor 20 and humidity sensor 21 on the fresh air intake duct. It determines that the system will operate under bypass conditions during the transition season or when there are large changes in outdoor air. A PM2.5 sensor 17 is installed at the fresh air intake of the unit. When the PM2.5 sensor 17 detects a value lower than the set value, it opens electric valve 19 and electric valve 20, closes electric valve 31 and electric valve 45, and adjusts the frequency of the EC fan to increase the fresh air volume. When the PM2.5 sensor 17 detects a value higher than the set value, it opens electric valve 31 and electric valve 20, closes electric valve 19 and electric valve 45, and adjusts the frequency of the EC fan to increase the fresh air volume.

[0041] (iii) When the indoor rooms are cooled with free fresh air in winter, the fresh air unit can be operated in the fresh air bypass mode. The corresponding valves are opened and closed according to the detection value of PM2.5 sensor 17 to solve the cooling problem of the indoor rooms.

Claims

1. A fresh air handling unit, comprising a fan housing (1), wherein a fresh air inlet (2) and a fresh air outlet (3) are respectively provided on both sides of the fan housing (1), characterized in that... The fan housing (1) is provided with a fan section near the fresh air outlet (3). The fan section includes an EC fan wall (4). Several fans (5) are installed in the EC fan wall (4). The fan housing (1) is provided with partition 1 (6) and partition 2 (7) at intervals. The partition 1 (6) and partition 2 (7) are connected by partition 3 (8). The partition 1 (6) is provided with electric valve 1 (9). The partition 2 (7) and partition 3 (8) are provided with electric valve 2 (10) and electric valve 3 (11) respectively. The filter section, the air section and the heat exchange coil section are provided below the partition 1 (6) and the partition 2 (7) and partition 3 (8).

2. A fresh air handling unit according to claim 1, characterized in that... The filter section includes a filter (12), which is located below the partition three (8). The partition one (6) is provided with an air inlet for the filter section. The filter section and the empty section are provided with a partition four (13), which is provided with a ventilation opening.

3. A fresh air handling unit according to claim 2, characterized in that... A partition five (14) is provided between the empty section and the heat exchange coil section, and an electric valve four (15) is provided on the partition five (14).

4. A fresh air handling unit according to claim 1 or 3, characterized in that... The heat exchange coil section includes a heat exchange coil (16), which is located below the third partition (8). The second partition (7) is provided with an air outlet for the heat exchange coil section.

5. A fresh air handling unit according to claim 1, characterized in that... A PM2.5 sensor (17) is provided between the fresh air inlet (2) and the partition (6), and an air volume sensor (18) is provided between the EC fan wall (4) and the fresh air outlet (3).

6. A fresh air handling unit according to claim 1, characterized in that... The fan (5) is a variable frequency unit, and its maximum air volume is configured to be twice the rated fresh air volume under air conditioning conditions.

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