1. The difference between a constant air volume system and a variable air volume system
In HVAC air handling systems, constant air volume (CAV) and variable air volume (VAV) are the two mainstream air supply control methods, and they have different operating conditions requirements for filters.
Constant air volume system (CAV)
The air supply volume of the constant air volume system remains constant and does not adjust with load changes. The system operates continuously under constant air volume, and the filter is in stable air flow conditions for a long time. CAV systems are usually used in places such as clean rooms and operating rooms that require high air supply stability.
Variable air volume system (VAV)
The air supply volume of the variable air volume system is dynamically adjusted according to changes in indoor load. The air volume decreases at partial load and increases at full load. The filter faces changes in wind speed and air flow fluctuations. Comfort air conditioners in office buildings, hotels, shopping malls, etc. usually use VAV systems.
The V-type high-efficiency filter (V-Bank) needs to adapt to both working conditions at the same time - it can operate stably under constant air volume and maintain performance during fluctuations in air volume.
2. Application of V-shaped filter in constant air volume system
The constant air volume system is a standard application scenario for V-shaped filters. The filter continues to operate at the designed air volume and the working conditions are stable.
Operating characteristics
Constant air volume and stable air flow
The resistance gradually increases with the increase of dust holding capacity.
Replacement cycle can be accurately predicted
Adaptability of V-type filter V-type filter can give full play to the performance advantages of low resistance and high efficiency in a constant air volume system. The initial resistance under rated air volume can be as low as ≤200Pa. As the running time increases, the resistance gradually increases to the final resistance, and the system fan needs to have sufficient head margin.
Key points for selection
Select the specifications matching the rated air volume according to the system design air volume.
It is recommended to reserve 20%-30% of the fan pressure head margin
Install a differential pressure gauge to monitor changes in resistance, and arrange replacement when the resistance reaches 2 times the initial resistance.
3. Application of V-shaped filter in variable air volume system
V-type filters are also suitable for variable air volume systems. Its structural design takes into account the special needs under variable air volume conditions.
Operating characteristics
Dynamic adjustment of air volume with load changes
Wind speed decreases at part load and increases at full load
Filters need to maintain performance over a wide range of wind speeds
Adaptability of V-type filters
Strong structure The V-shaped arrangement of multiple filter elements in the V-shaped filter has high structural strength and can maintain stable shape under wind speed fluctuations and air flow changes, making the filter material less likely to shake or be damaged.
The wide wind speed adaptable V-shaped filter can operate stably in a wide wind speed range. Under the initial resistance condition of 250Pa, the wind speed can reach 2.5m/s, which meets the wind speed change requirements of the VAV system between partial load and full load.
Efficiency Stability: The filtration efficiency remains stable when the air volume changes, and does not decrease as the wind speed decreases, nor does the penetration rate increase significantly as the wind speed increases.
Key points for selection
Select the model according to the maximum design air volume of the system to ensure that the resistance does not exceed the standard under the peak air volume.
Confirm the uniformity of airflow distribution at low wind speeds
It is recommended to configure a differential pressure transmitter to track resistance changes in real time.
4. Performance comparison of V-type filters in two systems
Contrast Dimensions
Constant air volume system (CAV)
Variable air volume system (VAV)
Working condition characteristics
Constant air volume and stable working conditions
Changes in air volume and fluctuations in wind speed
Advantages of V-type filter
Low resistance operation, predictable service life
Sturdy structure, adaptable to wide wind speeds
Selection reference air volume
Design air volume
Maximum design air volume
Resistance monitoring
Periodic readings of differential pressure gauge
Real-time monitoring of differential pressure transmitter
Replace judgment
The resistance reaches 2 times the initial resistance
At the maximum air volume, the resistance reaches 2 times the initial resistance
5. Precautions for model selection
1. Select the VAV system based on the maximum air volume. When selecting the VAV system, the maximum design air volume is the basis, not the average air volume. Make sure that the filter resistance is still within the tolerance of the system fan at peak air volume.
2. Reserve pressure head margin. The VAV system has the highest resistance at the maximum air volume, and the fan must have sufficient pressure head. It is recommended to reserve 20%-30% margin.
3. Efficiency level selection The efficiency level in the variable air volume system does not affect the air volume adaptability. Both H13 and H14 can be used in VAV systems.
4. Confirm the installation direction. The V-shaped filter has requirements for the air inlet direction and the air outlet direction. During installation, it must be installed correctly in the direction of the arrow and not in the opposite direction.
6. Product features of Aili Industrial V-type high-efficiency filter
Aili Industry has the following characteristics in the field of V-type high-efficiency filters:
Adapted to CAV and VAV systems, Ai Li Industrial V-type high-efficiency filter has a strong structure and can maintain stable performance under constant air volume and variable air volume conditions. The wind speed can reach 2.5m/s (under the condition of 250Pa initial resistance). It is suitable for both constant air volume and variable air volume HVAC systems.
Independent production of the entire industry chain Aili Industry has been deeply involved in the field of purification equipment for more than 20 years, and has built a closed loop of the entire industry chain from fan research and development, control system development to high-efficiency filter production to ensure the matching between various components and the overall performance of the system.
Strictly adhere to international standards. Products strictly comply with EN 1822 standards, and the filtration efficiency levels cover H13 and H14.
Large air volume design, rated air volume covers the range of 2400-4200m³/h, adapting to the needs of various HVAC systems.
. Each V-type high-efficiency filter undergoes strict scanning and leak detection testing before leaving the factory to ensure that the efficiency and resistance indicators meet the requirements
If you want to know more about the selection details of V-type high-efficiency filters in constant air volume or variable air volume systems, you can contact the Aili industrial engineering technical team and provide the system type and air volume parameters to obtain an adaptation plan.
HEPA installation should be carried out according to the airflow direction and installation drawing confirmed on site: first check the filter and frame, then clean the installation surface, press the seal evenly, and finally verify the air volume and seal under specified operating conditions.
When it is found that the HEPA installation direction is inconsistent with the product or box identification, the acceptance of this position should be suspended, the supplier's drawings and airflow arrows should be checked, and then adjusted according to the allowed installation method. Just because the filter fits into the frame doesn't mean the orientation is correct.
When purchasing HEPA, you should at least clarify the outer frame size, efficiency level and applicable standards, rated air volume, resistance, structure, sealing method, use environment and testing data requirements. The old filter element replacement project also requires installation frame and disassembly and assembly path information.
Differences in high-efficiency filter quotations may come from efficiency levels, filter materials, structural dimensions, resistance requirements, sealing methods, detection range and order quantity. When comparing prices, you should first confirm whether each quotation corresponds to the same technical conditions.
The installation quality of the liquid tank high-efficiency filter directly affects the sealing effect and cleanliness. Before installation, it is necessary to check that the appearance of the filter is not deformed or damaged, that the liquid tank is intact, and that the box knife edge is flat and free of burrs. During installation, pay attention to controlling the injection amount of sealant to 70%-80% of the depth of the liquid tank, and inject glue evenly and continuously along the periphery of the liquid tank. The filter must be vertically embedded in the knife edge and pushed into place; after installation, it is recommended to conduct a visual inspection, a PAO leak test and an initial resistance record. Common problems include sealant overflow (too much glue), insufficient sealant (too little glue), difficulty in pushing the filter (skew or size mismatch), and PAO leak detection frame leakage (insufficient insertion depth or missing glue). Aili industrial liquid tank high-efficiency filter is provided with polyurethane sealant and installation guidance materials, and the engineering technical team can provide installation technical guidance support.
The liquid tank high-efficiency filter and the ordinary non-partition high-efficiency filter belong to the non-partition filter category. The core difference lies in the frame structure and sealing method. The liquid tank filter frame has a liquid tank groove, and liquid sealant is injected to achieve sealing. The sealant flows and fills all irregular gaps. It has high long-term reliability and is suitable for ISO class 5 and above clean rooms. Ordinary filters without partitions are sealed by sealing tape extrusion, with a simple structure and low cost, and are suitable for ISO class 5 and below scenarios. The filtration area of the liquid tank filter of the same size is slightly smaller (about 5%-10% less), the price is higher, and the replacement operation is cleaner. When selecting, a comprehensive judgment must be made based on the cleanliness level, leak detection requirements, replacement frequency and budget. Aili Industrial produces two types of filters at the same time, with efficiency levels covering H13, H14 and U15-U17. Each unit has been tested and a test report has been issued.
The liquid tank high-efficiency filter and the ordinary non-partition high-efficiency filter belong to the non-partition filter category. The core difference lies in the frame structure and sealing method. The liquid tank filter frame has a liquid tank groove, and liquid sealant is injected to achieve sealing. The sealant flows and fills all irregular gaps. It has high long-term reliability and is suitable for ISO class 5 and above clean rooms. Ordinary filters without partitions are sealed by sealing tape extrusion, with a simple structure and low cost, and are suitable for ISO class 5 and below scenarios. The filtration area of the liquid tank filter of the same size is slightly smaller (about 5%-10% less), the price is higher, and the replacement operation is cleaner. When selecting, a comprehensive judgment must be made based on the cleanliness level, leak detection requirements, replacement frequency and budget. Aili Industrial produces two types of filters at the same time, with efficiency levels covering H13, H14 and U15-U17. Each unit has been tested and a test report has been issued.
V-type high-efficiency filter can reach H13 and H14 levels of EN1822:2009 standard. The total MPPS efficiency of H13 is ≥99.95%, and the local penetration rate is ≤0.25%; the total MPPS efficiency of H14 is ≥99.995%, and the local penetration rate is ≤0.025%. H13 is suitable for ISO7-8 clean rooms, electronic assembly, food processing and other scenarios; H14 is suitable for ISO5-6 clean rooms, pharmaceutical GMP, hospital operating rooms, semiconductor manufacturing and other key places. The V-shaped filter is designed with a V-shaped structure and can achieve large air volume carrying and controllable resistance in both H13 and H14 grades. When selecting, a comprehensive judgment must be made based on cleanliness level requirements, industry specifications and system air volume. Aili industrial V-type high-efficiency filters strictly comply with the EN1822 standard, and the efficiency levels cover H13 and H14. H14-level products are scanned and tested for leaks one by one, and test reports are provided.
The initial resistance is the pressure difference value of the new V-type high-efficiency filter under the rated air volume, in Pa, which is the basic parameter for selection, operation and maintenance. The initial resistance of V-type filter H13 grade is usually ≤200Pa, and the initial resistance of H14 grade is usually ≤250Pa. Under the same conditions, the resistance of H14 is slightly higher than H13. The initial resistance is used for fan head calculation and energy consumption assessment during selection, and is used as a basis for replacement judgment during operation - the final resistance is usually set to twice the initial resistance. When the actual measured initial resistance is too high, you need to check whether the actual air volume matches the rated air volume, and check whether the installation is standardized. Initial resistance is an important parameter affecting operating costs. Aili industrial V-type high-efficiency filter is designed with low resistance. The initial resistance of H13 is ≤200Pa, and the initial resistance of H14 is ≤250Pa. Each unit has been tested for resistance and a test report has been issued.
V-type high-efficiency filters are suitable for both constant air volume (CAV) and variable air volume (VAV) HVAC systems. The air volume of the CAV system is constant and the working conditions are stable. The V-shaped filter can take advantage of low resistance and high efficiency when selected according to the designed air volume. The air volume of the VAV system is dynamically adjusted as the load changes. The V-shaped filter has a strong structure and good adaptability to wide wind speeds. The wind speed can reach 2.5m/s under the initial resistance condition of 250Pa, adapting to wind speed fluctuation conditions. When selecting the VAV system, the maximum design air volume should be used as the basis, and a 20%-30% fan pressure head margin should be reserved. It is also recommended to configure a differential pressure transmitter to monitor the resistance in real time. V-type filter efficiency grade (H13/H14) does not affect the adaptability of the air volume system. Aili Industrial V-type high-efficiency filter has a solid structure, rated air volume covering 2400-4200m³/h, and is suitable for CAV and VAV systems. Each unit has been scanned and tested for leaks one by one and a test report has been issued.
The selection of large air volume V-type high-efficiency filter requires comprehensive consideration of four core parameters: rated air volume, overall size, initial resistance and efficiency level. Common specifications include rated air volume covering 850-4200m³/h, external dimensions ranging from 287×592×292mm to 1220×610×292mm, and initial resistance as low as ≤200Pa. The selection steps include calculating the total air volume of the system, determining the air volume requirement of a single unit, selecting the overall dimensions according to the parameter table, checking the installation space (especially the depth direction, the standard is 292mm), selecting the efficiency level (H13 or H14), checking the initial resistance and evaluating the replacement cycle. It is recommended to reserve 10%-20% air volume margin when selecting a model to avoid neglecting the depth size, the impact of efficiency level on air volume, and the difference between initial resistance and final resistance. Aili Industrial provides a variety of dimensions and V-shaped configurations, with rated air volume covering 850-4200m³/h. It strictly complies with the EN1822 standard. Each unit has been scanned and tested for leaks one by one and a test report has been issued.
The V-type high-efficiency filter is arranged in a V-shape with multiple filter elements without partitions, which increases the filtration area to 3-5 times that of ordinary flat-plate filters under the same external dimensions. Its core principle is to expand the filter material from a two-dimensional plane to a three-dimensional space, making full use of the depth direction of the frame. The increased filtration area brings practical advantages such as low resistance (initial resistance can be as low as ≤200Pa), large air volume (rated air volume can reach 2400-4200m³/h), high dust holding capacity and reduced number of filters. V-type filters are suitable for large air volume scenarios in limited spaces such as the end of air-conditioning boxes, compact HVAC systems, return air ducts in clean factories, and upgrades of existing systems. When selecting, you need to confirm the installation depth, select a V-shaped configuration according to the air volume, and check the system resistance. Aili industrial V-type high-efficiency filters strictly comply with the EN1822 standard and are available in 3V, 4V, and 5V specifications. Each unit has been scanned and tested for leaks one by one and a test report has been issued.
V-Bank high-efficiency filter (V-type combined high-efficiency filter) uses multiple filter elements without partitions to form a V-shaped structure. The rated air volume can reach 2400-4200m³/h. It is suitable for constant air volume (CAV) and variable air volume (VAV) HVAC systems. Typical application scenarios include hospital operating rooms and ICUs, pharmaceutical GMP workshops, electronic and semiconductor clean workshops, food processing plants, data centers, hotels and schools and other commercial buildings, as well as industrial ventilation facilities such as power plants. V-Bank filters can be used as high-efficiency filtration or ULPA pre-protection at the end of air conditioning boxes in HVAC systems. They have technical advantages such as large air volume carrying capacity, low operating resistance, high dust holding capacity, and saving installation space. Aili Industrial V-Bank high-efficiency filters strictly comply with EN1822 standards, with efficiency levels covering H13 and H14, adapting to the needs of various HVAC air treatment systems. Each unit has been scanned and tested for leaks one by one and a test report has been issued.
The V-type partitionless high-efficiency filter uses multiple partition-less filter elements to form a V-shaped structure. The filtration area can reach 3-5 times that of ordinary filters, the rated air volume can reach 2400-4200m³/h, and the initial resistance can be as low as ≤200Pa. In large air volume systems, compared with ordinary high-efficiency filters, V-type filters have the advantages of reducing the number of filters, saving installation space, reducing installation costs, reducing operating energy consumption, and extending the replacement cycle. The efficiency level covers H13 and H14, and is suitable for large air volume scenarios such as terminal filtration of air-conditioning boxes, electronic semiconductors, pharmaceuticals and medical care, and power plants. When selecting, you need to pay attention to parameters such as rated air volume, initial resistance, efficiency level, and overall dimensions. Aili Industrial V-type partitionless high-efficiency filter strictly complies with the EN1822 standard and provides large air volume design, low resistance and high dust holding capacity, optional multi-material frames and unit-by-unit inspection services.
The V-type high-efficiency filter (V-Bank) uses multiple filter elements without partitions to form a V-shaped structure. The filtration area can reach 3-5 times that of ordinary filters. The designed air volume is more than 2 times higher than that of high-efficiency filters with partitions. The initial resistance can be as low as ≤200Pa. Compared with ordinary high-efficiency filters, V-type filters require fewer installations, smaller installation space, lower operating resistance, higher dust holding capacity and longer service life under the same air volume. The efficiency level covers H13 and H14, and is mainly used in scenarios such as terminal filtration of air-conditioning boxes, large air volume HVAC systems, electronic semiconductors, pharmaceuticals, medical and power plants. Aili industrial V-type high-efficiency filters strictly comply with the EN1822 standard, provide multiple specifications and are tested one by one, and support customized production.
The thickness (50mm, 70mm, 90mm, 120mm) and filter area of the high-efficiency filter without partitions directly affect the air volume carrying capacity, initial pressure difference, dust holding capacity and service life. 70mm is the standard configuration of FFU, which strikes a balance between space occupation and performance; 90mm and 120mm are suitable for equipment with ample space such as air-conditioning boxes, with larger filter area and longer replacement cycle. When selecting, a comprehensive judgment must be made based on the size of the installation space, system air volume, fan head margin and full life cycle cost. If space allows, choosing a thicker filter, lower energy consumption and longer replacement intervals can usually pay back the cost difference within 1-2 years. Aili Industrial provides multiple thickness specifications of 50-120mm and non-standard customization services. Each unit is scanned and tested for leaks one by one and a test report is issued. The engineering and technical team can assist in air volume calculation and resistance calculation.
The partition-less high-efficiency filter uses ultra-fine glass fiber filter paper and hot-melt adhesive line separation technology, and can cover the full range of efficiency levels of H13, H14 and ULPA U15, U16, and U17. According to the EN1822 standard, H13 efficiency ≥ 99.95%, H14 ≥ 99.995%, U15 ≥ 99.9995%, U16 ≥ 99.99995%, U17 ≥ 99.999995%. Different levels correspond to different cleanliness requirements - H13 is suitable for ISO 7-8 clean rooms, H14 is suitable for ISO 5-6 clean rooms, and the local penetration rates of H13 and H14 differ by ten times. ULPA conducts efficiency assessments in the particle size range of 0.1-0.2μm and is suitable for high cleanliness environments of ISO level 4 and above. When selecting a model, a comprehensive balance must be made based on the cleanliness level, industry standards, system air volume and budget. Aili Industrial has independent production capabilities throughout the industry chain and strictly follows the EN1822 standard. Each filter is scanned and tested for leaks one by one and a test report is provided. It supports full series customization of H13, H14 and U15-U17.
When the installation space of FFU, EFU, clean shed or other clean equipment is limited, high-efficiency filters without partitions can be considered. The partition-less structure uses glue lines to fix the fold distance of the filter material, and has a certain design space in terms of filter thickness, filter area and internal structure. The actual selection should not only focus on the filter thickness, but also need to comprehensively consider the filtration efficiency, target air volume, initial resistance, fan static pressure, sealing method and later replacement space. Aili Industry can match the specifications of high-efficiency filters without partitions based on the equipment installation dimensions and operating parameters.
Partitionless high-efficiency filters can be used in clean environments such as semiconductors, electronic manufacturing, photovoltaics, pharmaceuticals, laboratories and precision manufacturing according to different specifications, and are often used in conjunction with FFU, EFU, clean sheds and clean room terminal air supply equipment. Different applications have different requirements for filtration efficiency, air volume, resistance, size, thickness and sealing methods, so selection needs to be based on specific equipment and clean environments. Aili Industry can match the specifications of high-efficiency filters without partitions based on industry applications, equipment structures and project parameters.
High-efficiency filters without partitions usually adopt filter material folding, glue line separation and outer frame sealing structure, without using traditional paper partitions or aluminum partitions. Its specifications mainly include overall dimensions, thickness, filtration efficiency, air volume, initial resistance, outer frame material and sealing method, etc. When used in FFU, EFU, clean sheds and clean room terminal air supply equipment, it needs to be matched based on the installation space, fan performance and target air volume. Aili Industry can provide corresponding specifications and configurations of high-efficiency filters without partitions based on equipment size, air volume, filtration efficiency and usage environment.
Aili Industrial develops and manufactures
FFU, EFU, HEPA/ULPA air filters, high-efficiency air supply vents, fan boxes and other clean air equipment. Relying on motors, fans, control systems, filters and complete machine supporting capabilities, we provide selection and customization support for clean room and production equipment projects.
